The present disclosure relates generally to devices, systems, and methods for removal of biological tissue during surgical procedures. In particular, but not by way of limitation, the present disclosure relates to a specimen bag deployment assembly having integrated connection components for tissue segmentation and exteriorization.
One of the critical surgical steps of a Tissue Specimen Removal system is capturing and loading the tissue specimen in a containment component (see e.g. U.S. Pat. Nos. 9,522,034 and 9,649,147). Many systems and methods have been disclosed in these patents to load the tissue and maintain containment during the surgical steps to capture the tissue, collapse the opening of a flexible component to contain the tissue while exteriorizing (i.e., bringing the tissue outside of the body) the containment component and ensuring that the containment component remains in the position required for the next surgical step.
In addition, there are many containment components or Specimen Retrieval Pouches available that can perform the capturing and loading function of a tissue specimen. One such containment component may be a specimen bag made of a flexible material, such as but not limited to polyurethane, nylon ripstop, or other polymers or combination of polymers intended to provide the mechanical strength required and the containment needed to perform tissue specimen segmentation and subsequent removal of tissue segments through the incision.
Removing large tissue specimens safely, quickly, precisely, and cleanly requires great skill and care. Improvements in each of these aspects are continuously sought. In particular, efficient and effective tools are needed to segment the tissue specimen within the specimen bag to facilitate the tissue removal, through the minimum size incision site possible. Therefore, a need exists for devices, systems, and methods that improve the process of tissue segmentation and removal.
An aspect of the present disclosure provides a method for detecting leaks of a containment barrier of the present disclosure. The method may comprise placing the barrier in contact with one or more volumes of fluid such that the one or more volumes of fluid is in contact with a first surface and a second surface of the containment barrier. The method may then comprise placing a first electrode in contact with a first volume of fluid within in a first area defined by the first surface of the containment barrier. The method may then comprise, placing a second electrode in contact with a second volume of fluid in a second area defined by the second surface of the containment barrier, measuring electrical conductivity between the first and second electrodes; and determining a presence of a leak in the containment barrier based on a calculation using properties of the one or more volumes of fluid, the containment barrier, and the measured electrical conductivity.
Another aspect of the disclosure provides a device for detecting leaks of a containment barrier, the device comprising: an outer vessel configured to retain the containment barrier and one or more volumes of fluid within the outer vessel; a first electrode in contact with a first volume of fluid within in a first area defined by the first surface of the containment barrier; a second electrode in contact with a second volume of fluid in a second area defined by the second surface of the containment barrier; and a measurement device configured to measure electrical conductivity between the first and second electrodes.
The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments.
Increasingly, improvements in surgery techniques pertain to reducing the invasiveness of procedures. In particular, surgeons seek to perform “minimally invasive” procedures—meaning that incisions are limited to a particular size-whenever possible. However, many surgeries that can be performed almost entirely via very small incision sites end up requiring a last step that is very difficult to perform via a small incision site. That last step is the removal of excised tissue. Removing large portions of tissue, such as entire uteri, large portions of kidneys, or cancerous tumors, for example, creates a number of logistical challenges. The previous disclosures referenced throughout this present disclosure describe various devices, systems, and methods for segmenting these large pieces of tissue within a specimen bag while still inside the patient. Current approaches allow for the tissue to be segmented into small enough pieces that they can be pulled out one by one through the small incision site.
Several factors can make this process time consuming, difficult, messy, and/or lead to a patient risk. For example, if a portion of the tissue is calcified, currently available cutting devices may take a long time to cut through that portion. In such cases, bringing the tissue close to the top of the specimen bag and cutting it as the tissue is being extracted can take an hour or more, and may require many hands and tools in the area. If the tissue and specimen bag must be manipulated and handled excessively, the opening of the bag may slip back into the incision site. This can be particularly high risk to a patient if the tissue specimen is a cancerous tumor, because such specimens often contain liquid that can spill and spread cancer cells within the patient's body. The present disclosure provides devices, systems, and methods that improve the case, safety, and efficiency of segmenting a tissue specimen within a specimen bag.
One type of existing specimen bag or containment component system is a flexible material that is rolled or folded by a surgeon, attending surgeon and/or scrub nurse so that it can be inserted through the trocar or incision site and then opened once inside the patient's body. In this type of system, the surgeon first excises the tissue to be removed, and then manipulates the bag opening with laparoscopic tools in order to place the tissue specimen within the bag. After capture of the tissue, the bag opening is raised with laparoscopic graspers and led out of the incision site to be secured externally by the surgeon by hand or with the addition of Kelly clamps or snaps.
Some of these types of specimen bags incorporate a polymer ring that is formed or attached to the top of the bag to keep the bag opening biased to a fully open position. This polymer ring can help hold the exteriorized bag open and in an appropriate place so that it does not fall back into the peritoneum or other surgical site of a patient.
Another common type of specimen bag or containment component system uses a bag that is typically placed within a cannula or lumen for insertion into the peritoneum through a trocar or incision site and the specimen bag advanced beyond the cannula to access the opening.
Many specimen bag systems use a mechanical means to bias the bag opening to an extended position to assist the surgeon in placing the tissue specimen within the bag. Such systems may comprise a formed metal ring with a spring bias attached to the top of the specimen bag so that the spring bias opens the top of the specimen bag when it is outside of the cannula. Most of the systems that use a metal ring of this type also incorporate a string or suture material as a drawstring to close the bag opening for exteriorization. In these devices, the string may remain outside of the patient's body and be pulled to seal the bag. This string closes the opening while the metal ring is retracted back into the cannula leaving the bag free from the cannula and metal rings and also leaving the bag within the incision site after the cannula and metal ring are withdrawn. Then, the surgeon can use the string to pull the bag opening through the incision site. Other systems use a string or suture material as a drawstring that closes the bag opening and while doing so, tears the bag away from the metal ring, leaving the bag free from the metal rings and cannula. The string is then used to retrieve the bag opening through the incision site.
As previously described, the currently available specimen retrieval pouches are designed to contain tissue while a surgeon loads and subsequently exteriorizes the specimen bag. The Tissue Specimen Removal system described in the patents mentioned and incorporated above utilize tissue segmentation devices comprising wires, a return electrode, and other components. The Tissue Specimen Removal system of the present disclosure may integrate various tissue segmentation device components—for example, segmenting wires and a return electrode—and further include one or more “connectors.” The term “tissue segmentation device components,” or simply “segmenting components,” may refer to any type of cutting device that is configured to physically cut tissue. Often, these segmenting components comprise individual wires or wire loops, which cut tissue by being drawn through it by mechanical force, or with the assistance of RF energy, or with a combination of the two. However, any segmenting components described herein may include those referenced in each of the patents incorporated above, any referenced throughout this disclosure, or any other types of tissue cutting device known or yet to be created. In many embodiments, these segmenting components may be integrated into the specimen bag of the present disclosure prior to being deployed inside a patient. Examples of such specimen bags having integrated segmenting components (e.g., segmenting wire loops) are described later in this disclosure.
The term “connectors” may refer either to a connector housing comprising one or more connector pins, or to individual connector pins themselves. The “connector pins” may be referred to as “connector portions.” These connectors attach to, at one end, segmenting components within the specimen bag. The connectors are configured to allow later connection of a separate portion of a segmentation device. For ease of reference and differentiation between tissue segmentation device components, and this separate, connectable portion, the latter may be referred to herein as “connectable (tissue segmentation) equipment” or “a piece of connectable equipment.” For example, the connectable equipment may be a tensioning mechanism assembly configured to tension the segmenting components (cutting devices) against the tissue specimen in preparation for drawing them through the tissue. The connectable equipment, in embodiments, may apply the required force and RF energy to the segmentation components and carry the return current back to the RF generator. As such, a specimen bag of the present disclosure, which integrates connectors, segmentation wires, and a return electrode have additional components not required for passive specimen retrieval pouch applications, as the dividing of tissue in those instances is done by the surgeon using separate tools not integrated with or connected to the bag.
In devices of the present disclosure, which comprise specimen removal bags that may be connected with connectable tissue segmentation equipment, the components associated with the connectors are not required for the loading of the tissue, nor are they required during exteriorization. The devices and systems of the present disclosure includes these connectors because it is highly advantageous to integrate the one or more mechanisms for connection of tissue segmentation equipment (i.e., the connectors) into a tissue specimen collection bag itself. In particular, when collected tissue specimens need to be segmented while retained inside a specimen bag, it can be advantageous to a surgeon to be able to quickly and easily connect the segmenting components (e.g., segmentation wires or other cutting devices) to connectable tissue segmenting equipment (e.g., an RF powered tensioning device). Being able to activate and use the segmenting components quickly can save valuable time in critical moments after tissue mobilization. In embodiments, the segmenting components comprise a plurality of wire loops integrated with the bag. Having the ends of these segmenting wires managed and out of the way, but then readily accessible once needed, is highly desirable. This can reduce the time spent retrieving additional instruments and reduce risks associated with setting equipment down and picking it up multiple times. Therefore, the integrated connector system of the present disclosure provides several conveniences and advantages. During the loading of the tissue and exteriorization, however, the connectors and return electrode portion must be protected.
The present disclosure provides devices, systems, and methods for tissue specimen removal utilizing a specimen bag and an integrated connector carrier. Beginning with reference to
In an intermediate location between the specimen bag 10101 and a cannula assembly (not shown in
When the bag 10101 advances, the flexible ring 10102 begins opening the bag as the flexible ring 10102 extends beyond the distal edge 10205 of the outer tube 10203. As the connector carrier 10105 reaches the distal edge 10205, a mechanical anchor 10802 integrated into a top portion of the connector carrier 10105 may interface with an opening 10207 (also referred to herein as a “securing opening”) in the outer tube 10203 to secure it in a position within the cannula assembly 10201, as will be shown and described in later figures. The mechanical anchor 10802 may be implemented as a spring detent mechanism, which remains in a depressed position inside the cannula assembly 10201 until it reaches the opening 10207 and pops up, securing the connector carrier 10105 in that position within the outer tube 10203.
When the mechanical anchor 10802 of the connector carrier 10105 is secured in the outer tube securing opening 10207, the user can control the opening and closing of the bag by advancing or retracting the inner tube handle 10206. A hitch 10405 (shown more clearly in FIG. H) attaches to the flexible ring 10102 and is moved by the inner tube and handle 10206. The movement of the hitch 10405 causes the flexible ring 10102 holding the bag to slide around the sides of the connector carrier 10105. The flexible ring 10102 may therefore be unconstrained and reach a fully open bag position or be retracted so that the bag opening is closed or bunches up against the distal edge 10205 of the outer tube 10203 and connector carrier 10105. While the bag can open and close based on the movement of the flexible ring 10102, the connector carrier 10105 may remain within the outer tube 10203, protected from exposure to bodily fluids, tissue, and other biological material in the surgical site.
While the connector carrier mechanical anchor 10802 secured in relation to the outer tube 10203, the portion of the bag assembly that is distal to the outer tube 10203 remains open, as shown in FIG. C. FIG. C shows the inner tube 10206 pushed in all the way such that the inner tube 10206 is positioned mostly within the outer tube 10203. The specimen bag 10101 and flexible ring 10102 (though not depicted here) are, as a result, fully pushed out of the outer tube 10203. The flexible ring 10102 is not depicted here in order to show that the top of the specimen bag 10101 comprises a plurality of flexible loops 10310 by which the flexible ring 10102 attach to the specimen bag 10101. The flexible loops 10310 can be bunched up together (i.e., when initially rolled up in the cannula assembly 10201, or when the flexible ring 10102 is drawn back into the cannula assembly 10201), or they can be spread apart when the flexible ring 10102 is advanced, holding the top of the bag open.
As shown in FIG. C, the connector carrier 10105, however, remains within the outer tube 10203, having been secured by the mechanical anchor 10802 and securing opening 10207. In this manner, the connectors of the tissue segmentation components and connectable equipment are secured within the internal volume of the connector carrier 10105 and protected from the flexible ring travel. The flexible ring 10102, during the advancement and retraction of the handle 10204, travels along the sides of the connector carrier 10105, as will be shown and described in later figures. In addition, a return electrode cable 10108 (shown in FIGS. M and N) is placed within an internal cut out of the handle 10206 so that the return electrode cable is protected during bag advancement and retraction.
In this embodiment, the tissue is loaded once the bag is open; that is, once the handle 10206 is advanced forward and has caused the mechanical anchor 10802 to secure the connector carrier 10105 and the bag opening is opened by the unconstrained flexible ring 10102 After the tissue is loaded into the bag by the surgeon, the handle 10206 may be fully retracted, pulling the flexible ring 10102 by means of the hitch 10405 and inner tube handle 10206 back into the outer tube 10203. The flexible ring 10102 retracts along the connector carrier housing 10105 and back into the outer tube 10203.
In this position, the material comprising the specimen bag 10101, having been unfurled into an open bag, and now containing a tissue specimen, is now too large to be pulled back into the outer tube 10203. Therefore, the flexible loops 10310 bunch up against the distal edge 10205, causing the bag opening to be closed against the distal edge 10205 of the outer tube 10203. This allows the surgeon to pull the outer tube 10203 out of the incision site with the bag closed. The closed or bunched bag opening may then easily slide through the incision site. After the bag and its opening are fully exteriorized, the inner tube handle 10206 may be advanced once again until the flexible ring 10102 reopens the bag. Because the open flexible ring 10102 forms a somewhat rigid circle, the cannula and specimen bag opening can be rested upon the external surface of the patient abdomen just outside the incision site without rolling over, sliding away, or falling back into the incision. In other words, once the bag opening is fully exteriorized, the open flexible ring 10102 holds the bag in place so that the surgeon or attending surgeon does not need to hold the bag or add Kelly clamps to secure it in place. The loaded portion of the specimen bag may remain inside the patient so the surgeon can perform additional segmentation of the tissue inside the bag while it is inside the patient, such that it can be segmented into small enough portions to pass through the incision site. One benefit of being able to set the specimen bag opening and cannula assembly down quickly and safely is that a surgeon can save time and retrieve fewer instruments during critical moments in surgery.
After the bag exteriorization is complete, the outer tube 10203 and handle 10206 (i.e., the entire cannula assembly 10201) may be removed from the specimen bag assembly 10101. This detachment may be performed by advancing the handle 10206 beyond the position where the connector carrier mechanical anchor 10802 locks into securing opening 10207 of the outer tube 10203. Performing this advancement of the tube may be implemented by releasing the mechanical anchor 10802 from the opening 10207. This can be done in many ways including but not limited the following described embodiments. For example, in embodiments in which the mechanical anchor is a spring detent, the spring may be manually depressed while the handle 10206 is advanced. The handle 10206 can include a mechanical stop 10305, near the proximal grip portion 10204, that is inserted into the handle 10206 during manufacturing and shipment, thereby restricting the advancement of the handle 10206 to the location that secures the mechanical anchor 10802 into the outer tube 10203. The mechanical stop 10305 may be removed by the user to allow the handle to advance and allow the outer tube to be released from the mechanical anchor.
Another embodiment may comprise a mechanism designed into the outer tube 10203 that would have a control coupled to a lever that depresses the mechanical anchor, thereby releasing it from the outer tube securing opening 10207 and enabling advancement of the handle 10206 to a position that allows the outer tube 10203 to be detached.
In another embodiment, a control can be provided that allows the handle 10206 to be rotated causing the mechanical anchor 10802 to move in a radial direction which releases mechanical anchor 10802 feature thereby releasing it from the outer tube 10203. This enables the handle 10206 to be advanced and allows the outer tube 10203 to be detached. Those skilled in the art can envision other mechanisms that can be designed to allow the user to apply a control or action on the handle or another component that will either raise or defeat the force required to maintain any type of latch feature in relation to any securing feature of the outer tube 10203.
Figure D shows the specimen bag and cannula assembly 10201 immediately after advancement of the connector carrier 10105 beyond the securing feature location in the outer tube 10203. In this position, the connectors 10401 and the hitch 10405 between the inner tube handle 10206 and the flexible ring guide 10406 is exposed. Embodiments of each of these components are shown more clearly in FIG. H. The hitch mechanism 10405 shown is a simple coupling that allows the cannula assembly 10202 to be raised in relation to the hitch 10405, causing the detachment.
Turning briefly to FIG. N, an embodiment of the hitch 10405 that may implement the described detachment is shown. Once an interface point between the inner tube 10206 and the hitch 10405 are extended past the distal end of the outer tube 10203—this junction can separate. To separate these (now exposed) parts, a user may first lift up on the inner tube 10206 (which may still be attached to the outer tube 10203), and subsequently pull downward on the hitch 10405. This may allow the bag assembly (comprising the bag 10101, flexible ring 10102, connector carrier 10105, hitch 10405, and return electrode cable 10108) to completely separate from the cannula assembly 10201. That is, the cannula assembly 10201 may be detached, leaving behind a specimen-loaded lower portion of the bag inside the patient, and the opening the bag and connector carrier assembly 10105 outside of the patient incision.
Those skilled in the art can easily envision other methods to create a coupling of the inner tube handle 10206 to the flexible ring guide 10406 while located in the outer tube 10203 that allows a decoupling when extended out of the outer tube 10203.
When the cannula assembly 10201 is detached from the specimen bag assembly, the return electrode cable 10108 may be pulled out of the interior cutout of the inner tube handle 10206 leaving it (the bag and the cable) on the exterior patient abdominal surface. In this manner, after removal of the cannula assembly 10201, the surgeon is free to access the connectors and return electrode cable 10108 connection for the subsequent segmentation steps without having the cannula assembly 10201 interfere with the surgeon's focus on the subsequent segmentation process.
FIG. E shows the connector carrier 10105 which is configured to temporarily retain the connector housing(s) 10520. The connector housings 10520, shown in an enlarged view in FIG. F, are configured to connect one or more types of tissue segmentation equipment. The connector housings 10520 are housed in the connector carrier 10105 so that the specimen bag assembly 10100 may be integrated with a variety of types of tissue segmentation components within the bag. In the embodiments shown, the connector housings 10520 manage a plurality of wire loops 10601, which are one particular type of cutting device for tissue segmentation. The wire loops may be implemented by those shown and described in U.S. Pat. Nos. 9,649,147 and 9,522,034. Any other type of cutting device may be used without departing from the scope of the present disclosure.
The connector housing 10502 may be configured such that connector pins 10603 can be extracted in only one direction (i.e., up and away from the bag, thereby pulling the wires or other cutting devices in the direction of tissue that is to be cut). These connector pins allow a plurality of wire loops 10601 (or any other type of cutting device) to be connected to additional tissue segmentation equipment. An exemplary type of tissue segmentation equipment may comprise a tensioning mechanism assembly such as the one shown and described with reference to
The connectors shown can be easily connected to the tensioning mechanism assembly via a downward pressing motion onto the connectors. Then, the tension mechanism assembly may be pulled up and away from the connector carrier 10105, detaching the connector housing 10520. Then, the surgeon may move the tensioning mechanism assembly to a position directly above the center opening of the specimen bag 10101, above the specimen, and press a button on the tensioning mechanism assembly to tension the segmenting components (e.g., wire loops). In other words, the wires may be pulled taut against the surface of the tissue specimen. Because the connector pins 10603 may move independently of one another, the wires may be pulled taut against oddly shaped tissue specimens. That is, some connector pins and wires may be pulled further up into the tensioning mechanism assembly than others based on the shape of the tissue specimen a particular wire is in contact with.
The purpose of the connector housing 10502 is to retain a plurality (in this embodiment, four) of individual connection points (of, in this embodiment, wire loops) so that the user can plug in all individual connections with one plug in step. In other embodiments, there may be more connector pins per connector housing (for example, six, eight, or ten), to facilitate connections to equipment with more connection points. There may also be more connector housings 10502 than the two shown. The connector pins may also be configured in different shapes to couple with different types of equipment.
Each individual connector pin 10603 is configured to individually and independently pull away from the connector housing 10502. Each of the connector pins 10603 may therefore be manipulated separately, if necessary, to operate the connected cutting devices. If desired, the connector pins 10603 may be manually pulled and moved to facilitate manual sawing or cutting of tissue with the wire loops. In other words, the connector pins 10603 may be configured to attach to different types of tissue segmentation equipment or to none at all.
The specimen bag and cannula assembly as shown in the embodiments illustrated, have a return electrode cable 10108, which allows for the use of equipment aided with the addition of RF energy to the segmenting wires, as will be described in subsequent figures. The return electrode cable 10108 may be plugged into the RF segmentation equipment. However, the mechanism of segmentation of tissue specimen with these wires may be achieved by mechanical, electrical, or any combination of effects therein.
In the embodiment shown, the connector housing(s) 10520 connects a plurality of wire loops to a tensioning mechanism assembly in an efficient or otherwise reduced number of steps as compared to previously available mechanisms for connection to a tensioning mechanism assembly. However, the connector housing 10520 and connector pins 10603 may be used to connect to any type of multi-pin plug-in devices. Alternatively, the connector pins 10603 may be used to connect to mechanical, electrical, or other equipment to cutting devices. The structure of the particular connector housing 10520 shown has advantages of being able to click to allow a user to have confidence that a proper connection has been made. It also allows for the management of a plurality of wire loops or other complex segmentation components integrated within a specimen bag, and connection thereof to segmentation equipment in one step.
In order to facilitate the connector housing(s) 10520 retainment management and extraction, features may be added to the connector carrier 10105 and connector housing(s) 10520 such that the housings will be retained in place until such time when the housing is rotated (or moved) to provide an easier position for tensioning mechanism assembly connection and removal from the connector carrier 10105.
FIGS. H and I show one of the connector housings 10520 in two positions between which the connector housing 10520 may be rotated. In FIG. H, the connector housing 10520 is in a flat position conducive to storing and protecting the connector housing 10520, and in
Referring back to FIGS. F and G, a plurality of connector pins 10603 cover the plurality of wire loops 10601 and are individually removable from the connector housing 10520. In the embodiment shown, these connector pins 10603 themselves provide the physical connection from the wires or other segmentation components within the specimen bag 10101 to the tensioning mechanism assembly such as the one shown and described with reference to
In many embodiments, it may be necessary to be able to release the entire connector housing 10520 from the connector carrier 10105. For example, the connection of the segmenting equipment and the subsequent use thereof may require the segmenting equipment to be positioned over the center of the opening of the specimen bag.
When necessary, the connector housing 10105 may be returned from its upright position (for attachment to the tensioning mechanism) to its folded position (for retention within the connector carrier 10105). In other embodiments, to facilitate the rotation of the connector housing 10520 an additional feature referred to herein as a “pull-tab and cartridge mechanism” may be implemented. The pull-tab and cartridge mechanism 11001 is shown in FIG. K and comprises a pull-tab 11002 and a cartridge 11003. The cartridge 11003 may be positioned over a portion of the connector housing 10520 and/or connectors 10603. The cartridge(s) 11003 may be positioned in the configuration shown in FIG. K during manufacturing. The pull-tab 11002 may be pulled in the direction shown by the arrow in order to rotate the connector housing 10520 into the upright position, in which it is shown in
Once the cartridge 11003 and connector housing 10520 are upright, a user may continue pulling on the pull tab 11002 in the direction of the arrow depicted, and/or upward, which causes the cartridge 11002 to be detached from the connector housing 10520. It is contemplated that the force required to remove the cartridge 11003 from the connector housing 10520 is less than required to remove the connector housing 10520 from the connector carrier 10105 completely, in order to prevent accidental removal of the connector housing 10520. In embodiments, the pull tab 11002 may be attached to a protective barrier that temporarily lines the inside of the specimen bag 10101 during tissue loading. The protective barrier may be a flexible, coated, and/or slippery material that forms an open cylinder. The purpose of this protective barrier is to protect wires or other segmentation components inside the specimen bag 10101 from being moved when the tissue specimen is loaded. However, before the segmentation begins, the protective barrier may be removed as to not interfere with the segmentation process. The pull-tab 11002 provides a quick and convenient way to both rotate the connector housing and remove the protective barrier in one step.
FIGS. K and L show the steps to prepare the connector housing(s) for connection and/or tensioning. With the connector housing in the upright position, a surgeon can “stab” the (four-pin) connector housing 10502 with the segmenting equipment to achieve a one-step plug-in process. The connector housing 10502, having been retained within the connector carrier 10105, may be pulled up and away from the connector carrier 10105, and the surgeon may place the segmenting equipment over the center of the opening of the bag, directly above the tissue specimen. If the segmenting equipment is the tensioning device previously described, the single push of a button on the tensioning device (now plugged in) will tension each of the wire loops 10603 via the connected pins 10603, allowing the surgeon to sub-divide the tissue specimen with each of the wire loops via RF power.
FIG. M shows a side perspective view of the connector carrier 10105, the hitch 10405, and the inner tube handle 10206, and FIG. N shows a cross-section thereof. The return electrode cable 10108 is shown retained within a cut-out 10905 that runs from the cannula assembly 10201 to the connector carrier 10105 and into the specimen bag 10101. The return electrode cable 10108 may terminate within the specimen bag at a conductive pad to conduct any RF energy delivered by tissue segmenting equipment. The other end of the return electrode cable 10108 may be plugged into a piece of segmenting equipment to close the circuit.
FIG. O. shows the specimen bag assembly 10100 and cannula assembly 10201 in their completely detached configuration.
FIG. P. is a flowchart showing a method 120000 of the present disclosure. The method may comprise, at step 120001, inserting a cannula assembly of a tissue specimen removal device into an incision site of a surgery patient. The tissue specimen removal device may comprise a specimen bag, a flexible ring, the flexible ring configured to form a top opening of the specimen bag, and a connector carrier. The connector carrier may be configured to retain at least one connector housing, the at least one connector housing comprising one or more connector portions, and reside within an interior of the connector carrier. The connector carrier may be further configured to retain at least one connector housing, the at least one connector housing comprising one or more connector portions. The connector carrier may be further configured to reside within an interior of the connector carrier. The cannula assembly may comprise an inner tube handle portion and an outer tube portion. The method 12001 may further comprise advancing the inner tube handle of the cannula assembly to open the specimen bag and move the connector carrier from a position within the cannula assembly to outside the cannula assembly.
In embodiments, the connector carrier may further comprise a mechanical anchor, and the method 120000 may further comprise, at step 120003, releasing the mechanical anchor to move the connector carrier portion from a position within the cannula assembly to outside the cannula assembly. In embodiments, the method 120000 may further comprise, at step 120004, pulling the top opening of the specimen bag out of a patient incision site. In embodiments, the method 120000 may further comprise, at step 120004, detaching the cannula assembly from the specimen bag, the flexible ring, and the connector carrier. In embodiments, the method 120000 may further comprise, at step 120005, connecting at least one piece of tissue segmenting equipment to the one or more connector portions. In embodiments, the method 120000 may further comprise, at step 120006, rotating the at least one connector housing into an upright position. In embodiments, the method 120000 may further comprise, at step 120007, segmenting a tissue specimen using the at least one piece of tissue segmenting equipment.
A common method in monopolar electrosurgery of reducing alternate site burns is to use a contact quality monitor to detect the quality of return pad connection to the patient. This contact quality monitor uses an AC waveform as an interrogation signal applied between two separate return electrodes within the return pad. The resulting electrical parameters between the two separate electrodes allow the contact quality monitor system to determine the impedance of the tissue or patient connection in between the two electrodes. This impedance is used to infer the quality of the contact in both an absolute and relative manner.
Previous disclosures have described how the same method of impedance detection can be used on the return electrode within a specimen bag utilizing RF segmentation of wires, even though this is a bipolar application. The same principles applied to a return pad contact quality monitor system apply to the specimen bag in which a poor contact of tissue can be identified before RF energy is applied such that the bag can be manipulated to improve the return electrode contact with the tissue.
The present disclosure provides a method wherein the contact quality system comprises two separate return electrodes within the specimen bag and has a known resistance across the two electrodes. This method may result in a reference resistance that would effectively be in parallel with the tissue. In this manner, the sensitivity of the tissue impedance may be reduced, however the known impedance could be used to confirm that return electrode conductive layers are intact, and that the total return electrode impedance is within an acceptable range. This method may be used in applications where the return electrode is achieved with coatings on a flexible substrate where external mechanical forces applied to the substrate could compromise the impedance of the return electrode coating. Those skilled in the art can easily see that selection of the known resistance value can be chosen to optimize the sensitivity of the parameter of interest for the application. That is, other systems for measuring contact quality and site burns are designed for use in applications wherein the return pad is placed on a patient's skin. The application of RF energy in this disclosure, however, is directed to segmenting tissue. Tissue that needs to be segmented has different resistance values that need to be measured and considered. A higher resistance can be selected to allow the tissue impedance to dominate the measured impedance value and a lower resistance can be selected to allow the electrical impedance of the return electrode traces to dominate this measurement. This value can range from 0 ohms, or a single electrode, that would only provide the electrical impedance of the return electrode traces to an open which would include the tissue impedance as well as the electrical impedance of the return electrode connection. Other systems used with return pads on patient skin would not allow a value of less than 5 ohms, for example.
In addition to the impedance of the coated return electrode on a flexible substrate, the location of the resistance transition from the coated substrate to a cable poses a challenge under mechanical loading conditions due to the difference in elasticity and resulting sheer forces. An aspect of the present disclosure provides a method to create this transition by using a compression of a silver coating to the return cable. In this embodiment, a flat surface may be attached via soldering or crimping to the return electrode cable such that the flat surface is placed in intimate proximity to the silver coating. Compression may be applied to the silver coating against the flat surface to provide electrical coupling. In this manner, slight variations of the flexible substrate do not affect the overall resistance of the transition from the substrate to the flat surface as the compression holds the substrate in place. The size and shape of the flat surface can be chosen to provide the interface impedance to ensure adequate electrical transition between the coated substrate and cable. The method of measuring the electrical impedance of the return electrode traces may also detect changes in the impedance of this transition as well as the traces on the substrate.
Previous disclosures have identified that the RF tissue specimen removal device has an advantage in using a constant force tensioning mechanism, such as those shown and described with reference to
When RF cutting with a loop of wire wrapped around a tissue specimen with an axial mechanical load applied (see, e.g., exemplary wire loop devices shown in
One aspect of this increasing force is that the compression of the tissue due to the applied mechanical load increases during the cut. This compression may be observed by a change in the tissue impedance. At the beginning of a cut, the compression force begins at a nominal value determined by the steam pocket created around the initiated wire and the tissue impedance. As the force increases, compression of the tissue by the wire increases and the resulting impedance of the tissue reduces. This is primarily a result of the compressed tissue as well as a greater challenge for the RF energy to maintain the arcing required to sustain cutting. For most tissue specimens, this phenomenon does not have a negative impact, however with very large tissue specimens and very large applied mechanical loads, the RF energy required to sustain the cut through the end of the cut can be challenged. This effect may beneficially be considered in selection of the applied load and range of tissue compression and sizes for the system.
An alternative to a constant force, an aspect of the present disclosure a variable force mechanism to apply the load to the segmentation wires. The load may be varied during the cut from a high value to a lower value to maintain a range of applied force. This approach would keep the impedance more consistent and increase the ability for the RF energy to sustain the cut.
The variable force can be applied in a linear reduction using a starting applied force and a predetermined finishing force that would be chosen to model typical tissue compression and sizes. It can also be an exponential decay to more closely model the increase in force as the wire shape changes.
An adjustable applied force may be delivered with a DC motor. This motor may be coupled to the wire with a spool such as a winch, a worm gear or with a rack and pinion that travels a length that meets or exceeds the total wire cutting length required for the largest specimen. The DC motor can be used with a current driver that can modulate the applied force based on the measured tissue impedance. In this manner, the maximum force is applied to the wire that also maintains the ability of the generator delivery power to the tissue. The DC motor may also be selected with an intrinsic load characteristic that is in line with the range of applied forces desired to allow the force delivered by the motor to be controlled with a constant current.
Previous disclosures have described that RF tissue segmentation may be easily adapted to create a reusable portion that works with a disposable portion of the segmentation instrument. This has the benefit of reducing overall procedure cost, as well as reducing the amount of disposed material with each use.
One embodiment of a reusable segmentation instrument that was described is to use a tensioning mechanism that utilizes a motor to apply the force. Using a motor, such as a small DC motor, has an advantage in a reusable application in that the position of the segmentation instrument tensioning mechanism can be advanced or retracted automatically. This allows easy reloading of the segmentation instrument to prepare for the next use. This reloading is much more difficult with a coil spring embodiment. In addition, the motor can be incorporated with an encoder to allow real time position information of the wire travel during cutting, and during reloading as the segmentation instrument is prepared for the next use. This allows automatic tensioning for cutting and replacement of the tensioning mechanism to the pre-load position after the segmentation is complete. Using this embodiment, the reusable portion of the device may include the electronics required for communication of the segmentation instrument to a controller, the tensioning mechanism, and the user controls. The disposable portion maybe limited to the interface of the segmentation instrument with the segmentation wires.
The features and embodiments described above can be used on their own on in conjunction with and as improvements to the systems described below.
In one exemplary application, and as illustrated in
Except as where otherwise stated herein, the term “segmentation device” shall be understood to include a device for dividing tissue, and may include a mechanical segmentation action, and/or an electrosurgical dissection action, for example a bipolar segmentation action, or a monopolar action.
In some embodiments, and as illustrated in
The tissue segmentation parameters are obtained by analytical and/or experimental methods and are targeted boundary values that ensure optimal operation of the system 100 or components thereof, preferably while maintaining a safe tissue temperature.
In some embodiments, a tissue segmentation voltage parameter Vmin is defined as the minimum voltage required to begin the initiation of a segmentation cut by providing an arc through an active electrode exposure area between the electrode/wire and the tissue. In some embodiments, the tissue segmentation voltage parameter Vmin is defined as the minimum voltage required to sustain the segmentation cut. The tissue segmentation voltage parameter Vmin can be calculated by considering the dielectric value of the electrode or wire coating, the coating thickness, and the uniformity of the coating. The tissue segmentation voltage parameter Vmin may also or alternatively be determined experimentally by measuring the voltage between the electrode/wire and return at initiation and/or during a segmentation cut of a control tissue.
In some embodiments, the tissue segmentation current parameter Imin is defined as the minimum current required to meet the current density needed to create a tissue segmentation cut. In some embodiments, the tissue segmentation current parameter Imin is defined as the minimum current required to sustain a cutting effect. The tissue segmentation current parameter Imin value may be calculated by multiplying a known current density that achieves a desired cutting effect in a control tissue by an active electrode surface area. The tissue segmentation current parameter Imin may also or alternatively be determined experimentally by increasing the RF current applied to a control tissue until cutting occurs and measuring the current delivered to the control tissue. In some embodiments, the control tissue may be tissue of the patient during an electrosurgical procedure.
In some embodiments, a power factor angle PFAcut variable is measured during an electrosurgical procedure on a patient. The power factor angle PFAcut variable may be determined by measuring the phase angle between the voltage and current waveforms delivered to the electrosurgical device, and is a representation of the complex load impedance provided by the system, including the tissue, to the generator during the electrosurgical procedure. The power factor angle PFAcut variable may be measured and tracked, to determine if a short circuit condition or open circuit condition between an active electrode or active segmentation wires and a return electrode exists.
A direct impedance measurement from the controller 108 to determine a short circuit is difficult as the series cable inductance becomes dominant. Applicant has determined that the power factor angle PFAcut during a short circuit will appear mostly inductive and have a phase angle near 90 degrees. Therefore, a short circuit power factor angle parameter PFAshort may be experimentally determined by measuring the lowest, or least inductive, power factor angle PFAcut variable while a short circuit is intentionally applied between the active and return electrodes during RF activation. The lowest power factor angle PFAcut variable may then be defined as the short circuit power factor angle parameter PFAshort.
Similarly, a direct impedance measurement for an open circuit is difficult, due to the parallel system capacitance. The power factor angle PFAcut variable during an open circuit will appear mostly capacitive and have a phase angle near-90 degrees. The open circuit power factor angle parameter PFAopen, may therefore be experimentally determined by measuring the highest, or least capacitive, power factor angle PFAcut variable while an open circuit condition is known to exist between the active and return electrodes during RF activation. The highest power factor angle PFAcut variable may then be defined or assumed as the open circuit power factor angle parameter PFAopen.
In some embodiments, an open circuit and/or short circuit may be determined using the power factor PF instead of the power factor angle PFA previously described. The power factor is the ratio of the actual power being delivered, or real power Preal, to the product of the RMS voltage Vrms and the RMS current Irms. The product of the RMS voltage Vrms and the RMS current Irms may be referenced herein as the apparent power. This ratio is 1.0 when the real power and apparent power are the same, as would be the case when a purely resistive load is applied. As a more inductive or a more capacitive load is applied, the phase shift of these loads reduces the value of the ratio to approach zero as the real power reduces but the apparent power remains the same. In this manner, the power factor PF may be used instead of the power factor angle PFA, thereby providing or enabling the detection of a minimum power factor threshold for cutting, PFcut, a short circuit power factor threshold, PFshort and an open circuit power factor threshold, PFopen.
In some embodiments, the average real power Preal may be detected or derived using the voltage and current sensors as previously described; however the output of the sensors may be connected to an analog multiplier to obtain the instantaneous real power Preal. The output of the multiplier may then be coupled to an analog circuit with an inherent capacitance to provide the window for averaging the real power Preal. The average RMS voltage Vrms and RMS current Irms may also be measured using an analog RMS voltage and RMS current sensing circuit that provides an RMS analog output. The RMS output of these sensors may also be connected to a multiplier to obtain the instantaneous apparent power and, as previously described for the real power measurement, the output of the multiplier may be connected to an analog circuit with an inherent capacitance to provide the window for averaging the apparent power. This circuit may be read with an A/D converter so that the power factor PF can be easily calculated by dividing the average real power analog output by the average apparent power output.
In some embodiments, the output of the real power multiplier and the output of the apparent power multiplier may be coupled directly to an analog divider to obtain the instantaneous power factor PF. This output may be read with an A/D converter to directly measure the power factor, or may be connected to an analog circuit with an inherent capacitance to provide a window for averaging the power factor.
In some embodiments, a purely analog method of power factor calculation may include the use of comparators as threshold detectors to provide an analog short circuit and/or open circuit detection that does not require a microprocessor, FPGA or other software, or RTL programmable instruction set to perform.
The impedance Zcut variable may be deduced from the voltage V and current I variables (scc, e.g.
Relatedly, the power variable Peut may be deduced from the voltage V and current I values (see
In some embodiments, a method of improving the power efficiency delivered from the generator to the tissue may be provided. In some embodiments, the controller may use power factor correction. Power factor correction may be achieved by the use of a variable capacitance that may be adjusted by the controller (see e.g.
The energy variable Etissue delivered to the tissue, is defined by the accumulated energy applied to the tissue during the RF activation. The energy variable Etissue may be deduced by accumulating the real power component from the voltage V and current I values (see
The minimum rate of travel parameter Rmin may be determined experimentally by adjusting the power P, derived from the voltage V and current I applied to the active electrodes or wires, and measuring the rate of travel that achieves the maximum allowable temperature rise on the surface of a control tissue specimen. In some embodiments, the mechanical force F may be adjusted to a known mechanical force F of zero pounds-force or more. In addition to varying power and force, a vibration or other dynamic load may be applied to the wires to speed its progress upon sensing a low rate of travel.
The maximum rate of travel parameter Rmax may be determined experimentally by measuring the rate of rise with no mechanical F on the tensioning mechanism or electrode(s) or wire(s). This value indicates a condition where the wires are not applying a force to the tissue specimen, such as a broken wire.
Many methods may be used to measure or determine the rate of travel. In some embodiments, and as is illustrated in
In some embodiments, a plurality of motion sensors may be provided. The plurality of motion sensors may be configured to compare images at time TO against images at time T0+1 to determine a direction and/or a distance of movement of the tensioning mechanism, cutting electrode, and/or wire.
In some embodiments, the sensor(s) have one or more integrated circuits, a sensor optical lens, and a light source. In some embodiments, the sensor(s) have separate components specifically for the application. The area of focus on the spring may be near the spool of the spring cylinder on the flat side of the spring coil so that the movement of the spring appears as a horizontal, transverse, or X direction motion. In some embodiments, the area of focus of the optical sensor is along the extended portion of the spring away from the spring spool or cylinder. In some embodiments, the area of focus is on the top of the spool cylinder such that as the spring moves, the sensor is configured to detect rotational movement that is detected as both X and Y movement or transverse and longitudinal movement.
In some embodiments, one or more optical sensors are provided and configured to detect contrast changes rather than creates images. The contrast changes can be surface irregularities in the spring or force application mechanism or can be patterns that are created on the spring surface. In some embodiments, preselected or known and regular intervals of contrasting patterns may be provided on the moving component, such as the tensioning mechanism, cutting electrode, or wire, and one or more optical sensors are configured to count the number of patterns moving past the area of focus to determine rate of travel and distance of travel. In some embodiments, the patterns are configured to provide a reference interval to measure the rate. The patterns may be separate patterns integrated or modulated into a primary pattern or near a primary pattern as a secondary pattern, so as to provide additional information, such as absolute distance traveled, beginning or end of travel markers, and/or key points of distance traveled.
In some embodiments, the device may be configured to adjust a power in response to information detected and/or communicated by the sensor or plurality of sensors. For example, the device may be configured to increase a segmentation power being applied to a cutting electrode in response to a determination that the tensioning mechanism, electrode, or wire is translating or moving at a less than preferred rate. As another example, the device may be configured to decrease a segmentation power being applied to a cutting electrode in response to a determination that the tensioning mechanism, electrode, or wire is translating or moving at a greater than preferred rate.
In some embodiments, a wheel having a known diameter may be provided in contact with the spring or force application mechanism, and a measured rotation of the wheel provides an indication of spring travel. The rotation of the wheel can be measured by including spokes in the wheel of known width or angle and optically counting the number of spokes observed by a light source and detector located on opposing sides of the wheel.
In some embodiments, the wheel is mechanically coupled to a potentiometer or variable resistor. As the wheel rotates, the resistance of the potentiometer changes; the change in resistance may be used to calculate the corresponding change in travel of the spring.
In some embodiments, a resistive film is provided on an exposed top surface of the wheel. A variable resistance along the surface may be provided, varying from a low impedance value to a high impedance value as the wheel rotates. A pair of contacts can be placed in the center and edge of the resistive film surface such that rotation varies the resistance, and the rotation can be calculated by tracking these changes in resistance.
In some embodiments, the device may be configured to detect a capacitance change to determine a rate or distance of travel. In some embodiments, an electrical plate that does not cover the entire wheel surface is provided, such as a semicircle, having a second conductive semicircle. Applying a time varying voltage between these two plates, the change in capacitance may be measured as the wheel rotates. In this approach the change in travel of the spring can be calculated in a similar manner as the previous example with a resistive film.
In some embodiments, an encoder is mechanically coupled to the spring or force application mechanism to indicate a rate or distance of travel. The encoder may provide waveforms that can be used to determine a rate of travel using the phase of the two waveforms.
In some embodiments, and output of one or more sensors or a sensing circuit provides information that is used to calculate or infer a rate of travel. The electrosurgical instrument 102, which may also be referenced herein as a segmentation instrument, may use this information directly to determine if the rate of travel is acceptable. The segmentation instrument may include a processing device, an analog circuit, and/or a digital circuit to calculate, process, and/or track a sensor output. In some embodiments, the device may initiate an action responsive to the information from the one or more sensors, such as, for example only when a distance or rate of travel is outside an acceptable or expected range.
It may be beneficial to scale this information into units that are meaningful to users such as cm/second. In some embodiments, the device has a processor configured to scale a digital, analog, or other signal into an informative output in a manner known to those skilled in the art. One benefit of using this method is that the motion of the spring can be quantified in a traceable manner that can be compared to external measurement equipment. An additional benefit is that correction algorithms can be applied if a non-linearity is observed in the rate of travel through the entire range of travel of the spring or force application mechanism.
In some embodiments, the segmentation instrument has a processing device in communication with the sensor(s). In some embodiments, the segmentation device may have a microprocessor, state machine, and/or field programmable gate array (FPGA) to perform the processing and/or allow a user to configure the segmentation device.
In some embodiments, the signals are transmitted from the segmentation instrument to a separate device, such as a controller or another processing unit on-site or off-site, to perform this processing. The distance of travel variable Dtravel may be measured directly from a tensioning device in the electrosurgical device 102, and may be used to compare against a pre-tension distance of travel parameter Dpreten and a cut complete distance of travel parameter Dcomplete. The pre-tension distance of travel and cut complete distance of travel parameters Dpreten, Dcomplete are calculated by the tensioning mechanism and active electrode assembly design such that the pre-tension distance of travel parameter Dpreten indicates the minimum distance achieved during pre-tensioning with the largest intended tissue specimen, and the cut complete distance of travel parameter Dcomplete indicates the maximum distance achieved when the active electrode wires have finished the cut. See Applicant's application PCT/US15/41407 for details of the tensioning device. The variable Dtravel may also be used to measure the travel of each separate tensioning mechanism after pre-tension is applied. These values may be used to approximate the volume and/or shape of the tissue specimen by comparing the Dtravel at the completion of pre-tension against Dpreten. By using this approximation, the maximum energy delivered to the tissue parameter Emax, may be adjusted to accommodate the tissue specimen being segmented.
Those skilled in the art will recognize that the methods and or components employed to measure the rate of travel previously described herein may be used to determine, calculate, or infer a distance traveled. In some embodiments, a distance traveled is calculated or determined as a relative distance. In some embodiments, a measured distance is calculated or determined as an absolute distance, for example, where an initial position is known or if absolute position indicators are included, such as previously described.
In some embodiments, the device may be configured to transmit a signal or information related to the segmentation to the user. For example, the segmentation device may be configured to indicate a percentage of completion of a segmentation procedure, a rate of completion, a rate of travel, an absolute distance traveled, and/or a relative distance traveled.
In some embodiments, the segmentation device may be configured to transmit an auditory or visual warning signal to the user where the rate of segmentation, rate of travel, and/or other parameters are not within an expected range, such as an expected range that would be associated with a segmentation power being applied to the electrode(s). That is, an expected range of a travel rate may be associated with a particular power level and/or segmentation force. If the actual travel rate is outside the expected range, this may be an indication of a problem with the procedure, and the user may need to halt and/or adjust the procedure.
With brief reference now to
The extendable distal end portion of the segmentation instrument may be inserted into the cavity of the patient and in direct contact with the tissue to be segmented. This distal tip of the instrument tube, termed the introducer tube 1501, may have the opportunity to be a point of high frictional drag between the active segmenting wires and the tissue/introducer tube interface. Some embodiments therefore include dentals 1505 (see e.g. FIG. on a distal end of introducer tube-which allows the introducer tube to be firmly contacted with the tissue specimen, yet gives space for the segmentation wires to freely retract through the tissue and into the segmentation instrument without getting pinched between the tissue specimen and the distal tip of the introducer tube.
Some embodiments include a standoff platform 1506 to reduce friction. In some embodiments, the standoff 1506 may be a spherical standoff. Those skilled in the art will understand, however, that the platform 1506 may be in the form of any shape, as long as the platform provides intimate contact with the tissue and provides a clear space through which the active segmentation wires can travel. In some embodiments, the platform provides intimate instrument/segmentation tissue contact while still offering an open space where the segmentation wires can more freely travel between the tissue and the distal tip of the introducer tube 1501 (on the segmentation instrument).
In some embodiments, a distal tip of the introducer contains a lubricious and high temperature insert, such as PTFE, that reduces the friction of the wires traveling through the tube and into the instrument, as is illustrated in
Returning now to
Turning now to
In some embodiments, a flexible membrane is located near the distal end of the introducer. Semi-rigid “fingers” may be arranged around the circumference of the introducer shaft, under the membrane, and coupled to the proximal section of the introducer. Under the “fingers” is a ramp coupled to the distal most portion of the introducer located such that the ramp begins at the distal edge of the fingers in the normal position. When the proximal portion of the shaft is advanced toward the distal end of the introducer, the fingers are extended away from the introducer also extending the flexible membrane. This creates a protrusion that can be used to seal the inside of the peritoneum. A mechanical sealer can be applied as previously described to provide compression at the incision site.
In some embodiments, the introducer has a film attached near the distal end of the device. This film is arranged in a cross sectional axis of the introducer so that when the introducer is withdrawn to the proper location, the film may provide a seal to the incision site. In this embodiment, the introducer will be hold in place the by the user to maintain pneumoperitoneum or the use of the seal on the outside surface as previously describe can be used to help with holding the introducer in the proper location.
Those skilled in the art can understand that any combination of flexible membrane, inflation ring, or mechanical sealer can be used on the inside and/or outside surface of the incision site to provide a seal that maintains pneumoperitoneum. In addition, the distal most portion of the handle can incorporate many user interface features to enact the sealing features, including a slide that applied inflation or motion, a section of the tube that can be moved up or down along the shaft of the introducer, or a protrusion that acts and a lever to create the motion required to initiate the scaling.
In some embodiments (see e.g.
In some embodiments, the generator 104 may be coupled to a first set 120 of first, second, and third leads 114, 116, 118 (shown in
In some embodiments, the controller 108 may be configured to cause the cutting wires 122, 124 to apply radio frequency (RF) power to a tissue specimen (not shown) for segmentation and removal. Although just two wires 122, 124 are illustrated in
With reference now to
One method may include comparing 714 at least one detected tissue segmentation variable with a tissue segmentation parameter and/or comparing 716 at least one detected tissue segmentation variable with a second tissue segmentation variable, and adjusting 718 a tissue segmentation control signal in response to either comparing 714, 716.
The controller 108, 708 may be further configured to control the tissue segmentation variables so that a plurality or all of the cutting wires 122, 124 complete tissue segmentation cuts at substantially the same time. Completing the tissue segmentation cuts at substantially the same time may help manage temperature accumulation at each wire location.
The controller 108, 708 may be configured to cause substantially simultaneous cut completion by switching RF power between each of the cutting wires intended to apply the RF power. This may be achieved by switching the RF energy in a sequential algorithm for a fixed time period, switching the RF energy such that the slowest rate of travel mechanism receives the most energy, to control the cutting wires 122, 124 to have the same length of travel during the cuts or based on the electrical parameters such that those cutting wires 122, 124 indicating a different or lower impedance values or a lower length of travel during the same time span may receive more RF power on average than the remaining wire sets to maintain the cuts. Those skilled in the art will recognize that, if the electrode is not travelling, the steam pocket may collapse, resulting in a lower impedance; in contrast, if the cutting is active, the steam pocket may increase the impedance.
Particularly when using the multiplexed approach, the inactive time should be limited to maintain the steam or higher impedance around the wire to sustain cutting.
Inactive time should also be limited when a first tensioning mechanism or cutting wire 122, 124 is not advancing, or not advancing as quickly, as a second tensioning mechanism or cutting wire 122, 124, such as due to a highly calcified tissue specimen or some other means of failure (such as encountering a staple in tissue sample). In this case, the cutting wire 122, 124 or wire set that is not properly advancing may be excluded from receiving RF power. In some embodiments, the remaining cutting wires 122, 124 or wire sets can complete the cut.
Turning now to
Receiving 802 may include receiving the plurality of tissue segmentation variables over time.
The method 800 also includes comparing 804 one or more of the tissue segmentation variables with a respective tissue segmentation parameter, or comparing 806 one or more of the tissue segmentation variables with a second tissue segmentation variable, and, responsive to the comparing 804 or comparing 806, adjusting 808 an energy and/or segmentation force to a tissue specimen.
The method 800 may be achieved using the device illustrated in any of
The method 800 may include comparing a detected power factor angle PFAcut variable with a short circuit power factor angle parameter PFAshort and/or an open circuit power factor angle parameter PFAopen. The power factor angle parameters PFAshort, PFAopen are described in preceding sections of this disclosure.
Returning now to
For example, in the system 100, current and voltage sensors may be provided to give a separate real and imaginary component of the complex load impedance applied by the system 100 to the tissue. Those skilled in the art will understand that imaginary, or reactive, components of cable impedance may make measurement accuracy by a generator of a short circuit very difficult. However, by providing a system 100 or method 800 in which the real and imaginary components of the complex impedance are known, the real component may be used to provide a better measurement for shorts, opens and intermediate impedance values. In some embodiments, the system 100 or method 800 may include a short circuit and open circuit check and/or a mechanism for a short circuit and/or open circuit check.
The phase and amplitude of the complex load impedance may also be used as relative comparisons as with a short circuit, the cable inductance will be a significant contribution to the load resulting in a positive phase angle and at an open circuit the cable and system capacitance will be a significant contribution to the load resulting in a negative phase angle. Methods to calculate the phase include using an analog phase detector, comparing zero cross-over points and peak amplitudes, or using digital sampling and software methods such as a Goertzel algorithm.
In some embodiments, the system 100 may be configured such that the power or RF energy delivered to the tissue can be adjusted during the cut to provide controlled outcomes. For example, power variables applied to the wire(s) 122, 124 may be monitored and adjusted as desired, using the first and/or second sets 120, 130 of leads, or any suitable number of leads for monitoring and adjusting power to the wire(s) 122, 124, and any number of cutting wires 122, 124 may also be provided.
Those skilled in the art will understand that the leads 120, 130 may be configured to transmit digital and/or analog signals associated with the power variables or control signals. The RF power may be amplitude modulated to control the cut rate of travel. Using the rate of travel feedback, the power may be adjusted to maintain a substantially constant desired rate of travel, to maintain the rate of travel above a minimum value, Rmin, to ensure low temperature cutting, and/or to maintain the power below a maximum value to reduce the power delivered at the completion of the cut.
In some embodiments, a force gauge may be coupled to the tensioning mechanism, and the power may be adjusted to assist the spring in maintaining a substantially constant force and/or a force above or below a desired threshold for suitable tissue segmentation. These methods may be used for other means of applying the tissue segmentation force, such as a linear actuator or manual pull.
In some embodiments, the controller 108, 708 may be a box that is set on the generator 104 and has a separate power cord, or, in some embodiments, the controller 108, 708 may be unitary with, and a component of, the generator 104, as illustrated in
The controller 108, 708 may also be embodied as a battery powered device making it more portable and easier to use by reducing the need to duplicate AC power connections to perform the electrosurgical procedure.
The controller 108, 708 and/or generator 104 employing the controller 108, 708 may have the ability to measure the current I, voltage V, and/or other variables associated with the power delivered by the generator 104 prior to connecting the generator 104 output to the electrosurgical device 102. This allows the controller 108, 708 to ensure that the user has selected the proper generator setting before applying electrosurgical RF energy to the wire(s)/electrode(s) 122, 124, to ensure that the integrity of any coating on the wire(s)/electrode(s) 122, 124 is maintained for initiation.
In some embodiments, an internal resistor or resistors, selected to ensure that the proper voltage, current and power range Vmin, Vmax, Imin, Imax, Pmin, Pmax are being delivered by the generator 104, may be provided to ensure that the integrity of any coating on the wire(s)/electrode(s) 122, 124 is maintained. In some embodiments, the controller 108, 708 or system 100 is configured to alert the user, to recommend corrective action, and/or to initiate a communication with the generator 108, 708 to change a power setting in response to a determination that the integrity of a coating is compromised.
In some embodiments, the controller 108, 708 may have a means to apply power such as RF energy to individual tensioning mechanisms and wire sets in the electrosurgical device 102 so that the controller 108, 708 may selectively and/or sequentially energize the wires 122, 124.
In some embodiments, the user may select the proper sequence through a user interface 112 with the generator 104 or controller 108, as is illustrated in
In some embodiments, the controller 108 may be configured to determine a crest factor of the generator output, and to confirm the user has selected the proper output mode setting. In some embodiments, measuring the RMS or average voltage (current, power) and the peak voltage (current, power) are employed to deduce the crest factor.
Responsive to one or more of determining 902, 904, 906, 908, 910, 912, 914, 916, 918, the method 900 may include one or more of (a) advising 920 the operator to pre-tension the device 102, (b) adjusting power or suspending power and advising operator to change the power 922, (c) discontinuing 924 power activation and alerting operator, (d) determining 926 if a short circuit exists, (c) determining 928 if an open circuit exists, or (f) adjusting power or advising operator to change the power 930.
The method 900 may include, responsive to determining 926 that a short circuit exists, discontinuing 924 power activation and alerting the operator or adjusting power or advising operator to change the power 930.
The method 900 may include, responsive to determining 928 that an open circuit exists, discontinuing power activation and alerting the operator 924 or adjusting the power or advising the operator to change the power 930.
The method 900 may include requesting 932 to deliver power, applying 934 power, and removing 3036 power. Applying 934 power may be responsive to determining 902 that pretension has been applied. Removing 936 power may be responsive to determining 918 that the cut has been completed.
Turning now to
Similarly, in some embodiments, and as illustrated in
In some embodiments, a force gauge or wheatstone bridge-like device may be provided to measure a deflection of a touch probe to test deflection at the spring coil. Those skilled in the art will understand that greater deflection means more spring material is deflected, and in turn meaning further travel of the electrode or wire or sets 153, 160 of electrodes or wires.
In some embodiments, a bearing mount for each constant force spring 1904 may be provided. A measurement of the rotation of each bearing mount may be used to determine travel distance (and rate) of each spring and electrode or wire.
In some embodiments, a micro ‘radar’ optical measurement of each connector block along the axis of the connector block travel may be provided, to visually measure how far away each connector block is from the measuring sensor-thereby determining the travel distance (and rate) of each spring and electrode or wire.
In some embodiments, a resistive strip or set of strips or films may be applied in close proximity and along the travel of the tensioning mechanism. A contact may be attached to the tensioning mechanism or tensioning block near the distal end such that it is provided electrical coupling to the resistive strip or film. As the tensioning mechanism moves, the contact acts in a similar manner as a “wiper” on a variable resistor. By using an electrical circuit that applies a voltage cross the end of to the resistive film and the contact, a change in resistance can be measured that is related to the distance of travel. The rate of resistance change can also be measured and is related to the rate of travel.
In some embodiments, the contact and resistive strip as previously described are provided, but with a second conductive strip that is in parallel but not electrically coupled to the resistive strip. The contact provides an electrical coupling to both the resistive strip and the conductive strip. In some embodiments, the electrical circuit may apply the voltage across the fixed ends of the resistive and conductive strips. Those skilled in the art will understand that this approach may be modified to utilize a contact that is not directly connected to the strip but would operate in near proximity for the duration of travel. This approach allows an electrode to apply a variable capacitance or mutual inductance that could be used to measure the distance of travel or rate of change.
The mechanical segmentation force variable Fseg may be measured by a force gauge on the tensioning mechanism. The force gauge may be any gauge suitable for the intended purpose, including any analog, digital, or mechanical signaling mechanism. The mechanical segmentation force variable Fseg may be compared to a minimum mechanical segmentation force parameter Fmin to ensure that the correct mechanical load is being applied to the tissue specimen. The minimum mechanical segmentation force parameter Fmin may defined by the design specification of the tensioning mechanism force characteristics. In some embodiments, the minimum mechanical segmentation force parameter Fmin may be defined experimentally by measuring a force associated with a desired rate of travel of the electrode(s) at a known power level in a control tissue.
Continuing now with
The device 1300 may include a proximal portion 1302 that is detachably connected or connectable to a distal portion 1304. A connection region 1319 between the proximal portion 1302 and the distal portion 1304 may be a block of a wire tensioning mechanism, such that a disposable lumen 1303 is attached. The disposable lumen 1303 may provide a guide 1306 for one or more tensioning mechanisms having a post 1316 that connects to tensioning blocks 1318 on the proximal portion 1302, and may have connection points to enable the distal end 1308 to connect to the active electrode wire connections (not illustrated). The disposable lumen 1303 may also include a means 1310 to advance tensioning springs (or tensioning force mechanism) to a pre-tension position, a pre-tension mechanism 1312 that allows the user to pre-tension the tensioning mechanisms and an introducer 1314 for placement in the incision site and a bag (see e.g.,
With continued reference to
The user may connect the distal portion 1304 to the proximal portion 1302 by sliding the portions 1304, 1302 together such that the post(s) 1316 (see
Continuing with
The applied force generated by the tensioning mechanism in the proximal portion 1302 may be mechanically and electrically coupled from tensioning blocks 1318 through the posts 1316, through the alignment blocks 1320, through the distal end 1308 and through the active electrode connectors. In some embodiments, all patient contact areas may be part of a disposable lumen 1303, which may provide for simplified cleaning and reprocessing of the reusable portion including the proximal portion 1302.
In some embodiments, and as illustrated in
Some embodiments providing means for separating the reusable components from the patient contact components may include a disposable insert inside the reusable tissue segmentation device 1300. The disposable insert may capture the wires after the cut. In some embodiments, a device that can be easily disassembled so that the interior area that contains the wires after the cut can be cleaned, reassembled and re-sterilized.
Turning now to
In some embodiments, constant force springs 1503 are wound around a gear-like spool 1504 which can be locked into place, such as by a flange or tab(s) 1506 prior to tensioning or power activation.
In some embodiments, and with reference to
In some embodiments, a plurality of detent gate(s) 2306, such as four, are provided to engage each spring 2302 of a 4-spring assembly. In some embodiments, the gates 2306 are configured to lift or raise at a specified rotational angle of the collar 2308. In some embodiments, a first gate 2306a is configured to lift or disengage from a first spring 2302a before a second gate 2306b lifts or disengages from a second spring 2302b. The collar 2308 may be configured to control the disengagement in this manner.
In some embodiments, a motorized spring and/or a bivalve pneumatic instrument may be used in place of the slots 2310 in the collar 2308.
Turning now to
In some embodiments, and with reference still to
Those skilled in the art will also understand that the drawstring 2405 and/or other components described herein may be made of or have a surgical steel, a flexible metallic material, a metallic coating, a flexible metallic coating, a sterile polymeric material, a spring, a coil, a memory-retaining material, and/or other materials selected for the intended use in a surgical environment and for minimizing transfer of contaminates to the patient. In some embodiments, the drawstring 2405 may be configured to bias the introducer 2404 and bag 161, 2400 to a prepared-for-insertion or compressed configuration.
In some embodiments, and as illustrated in
In some embodiments, the return electrode cable 2602 and inflation tube 2606 are mechanically attached together and mechanically supported where they exit the removal bag 161 such that they can be used as a means to pull the bag 161 toward the incision site after the tissue specimen is loaded. After deflating the bag 161, the bag opening may be pulled through the incision site by pulling the return cable/inflation tube assembly 2602, 2606 until the bag opening or a portion of the bag opening is exteriorized allowing the user to pull the remaining bag opening out of the patient. This integration of the return electrode cable 2602 and tubing 2606 may be a molded assembly, a film applied around both components, layered together as one assembly, tied together along the length of common attachment, or can bonded using adhesive or other means.
Turning now to
In addition, the width W of the dimension in which the film 2702 is not attached to the bag 2700 defines a wire channel 2707. This wire channel 2707 is an important dimension related to the ability of a wire (e.g., wire 151 as illustrated, or any wire 122, 124 or electrode described herein) to find the perforation 2701 when the tensioning force is applied so that it creates the separation required to release the electrode(s)/wire(s) 151, 122, 124. This width W, combined with the elasticity and/or thickness T of the material 2702, can be adjusted in addition to the perforation per length values and patterns previously described to provide the optimal wire release performance.
In some embodiments, the width W of the wire channel 2707 for a tissue removal bag 2700 is less than 0.5 centimeters (or less than about 0.200 inches); in some embodiments, the width is less than about 1.63 centimeters (or less than about 0.064 inches). Another means to help increase the probability of the wire 151 separating the perforations is to have multiple perforation lines 2701 in parallel to each other in the film 2702 so that as the wire 151 is routed in the channel 2707, the chance of finding the line of perforations 2701 is greater.
Selection of the appropriate combination of these values can provide the release of the electrode(s)/wire(s) in a manner that advances as the electrode(s)/wire(s) advance during cutting, and can guide the electrode(s)/wire(s) along a perforation channel 2707, resulting in a more predictable segmentation cut. This may be accomplished with the same perforation per length values across some or all sections having the perforations 2701, can be enhanced by using different perforation per length values in different sections, can be a linear, logarithmic, or other pattern of increasing or decreasing perforation per length values, or can be patterns of perforations 2701 followed by open areas 2709 to enhance the separation as the electrode(s)/wire(s) travel(s).
Those skilled in the art will appreciate that as multiple wires are used within the bag, intersection points are created where a wire set intended to apply power such as RF energy to the tissue crosses in close proximity to the wire sets that are not intended to have power or RF energy. Some amount of power will tend to couple, either capacitively, inductively or conductively, to the inactive wire sets. This can result in cutting of unintended wire sets which can lower the current density, as the total active electrode surface area is increased, such that the desired cutting performance is not achieve. As such, this coupling must be managed to avoid unintended wire set cutting.
With brief reference to
In some embodiments, the coupling can be managed electrically by providing a higher isolation between the intended and unintended wire sets. This can be achieved by aligning the perforation portion of the channels at the intersection points. This provides the greatest benefit for conductive coupling and provides a higher dielectric for capacitive coupling.
In addition to increasing the isolation, the overall amplitude of the electric field can be reduced. This is achieved by controlling the amount of exposure the active wire has with the tissue. As the contact between the wire and tissue is increased, the effective impedance is reduced resulting in a lower electrical field amplitude along the wire. In addition, as the voltage on the wire sets reaches a level where arcing begins, the arc path will preferentially be through the tissue and not to the unintended wire sets.
The coupling can be managed mechanically be providing a higher mechanical load to the wire sets intended to cut verses the unintended wire sets. This can be achieved with separate pre-tension forces, or with different forces applied for the duration of the cutting process. If the coupling is observed between the intended and unintended wire sets, the differential force between the two wire sets will increase the separation between the two as the intended wire set advanced through the tissue. The increased separation will reduce the amplitude of the coupling between the two wire sets, and ultimately to an insignificant level.
With continued reference to
A feature may be combined with the wires to enhance the ability of the wire sets to break away from the bag perforations. For example, the wire 151 may have a wedge shape feature that is attached to the wire or Teflon tubing to cut or improve the tearing of the perforations as the wire moves through the tissue.
Some embodiments may be configured to reduce the likelihood of a cut tissue segment that is too large to remove through the incision site. In some embodiments, multiple layers of active electrode wire sets are attached with perforations to layers of the bag.
For example, if an electrosurgical device 102 is designed to have four tensioning mechanisms that apply power to four separate active electrode wire sets, the bag may include an outer layer, a second layer that has the return electrode coupled to the outer layer, and a series of internal layers stacked inside the bag. Each of these internal layers may be an insulated layer with perforations running the length of the layer that has four active electrode wire sets attached with perforations. These layers may conform to the shape of the outer layer so that they can be easily inserted into the outer layer. The layers may also have an opening in the bottom area of each layer so that the return electrode is exposed to the tissue when the internal layers are in place. The user may attach the connectors of the active electrode wire sets from the innermost layer to the electrosurgical device 102.
The tissue segmentation may be performed as described in Applicant's co-pending application PCT/US15/41407. When the segmentation is completed and the wires are removed from the layer, the layer may be removed by the surgeon by hand, such as by pulling on the exposed portion of the inner layer and causing the perforations in of the layer to separate, allowing the film to be removed. This removal exposes the next set of active electrode wire set connectors. A second electrosurgical device 102, or a device that can be reloaded to the fully extended position, can now be connected to the tissue removal bag in the same manner as previously described. Those skilled in the art can understand that this increases the number of segmentation cuts and reduces the chance that a large tissue segment will remain after all segmentation steps are completed. The layers of the bag may be constructed such that each internal layer is rotated slightly from all other layers to further reduce the likelihood of leaving a large tissue segment after all segmentation steps are completed.
Continuing with
For example,
Other examples of perforation patterns are illustrated in
In some embodiments, providing open windows 2709, or omission of the perforation layer at desired intervals or location(s), aides in wire release from the bag, as illustrated in
The ratio of windows 2709 to perforation walls may be adjusted or selected in a manner similar to the perforation per length value, to control the force required to release the wire 151 through the perforations. In addition, because the perforation walls cover the active electrode wire(s) 151 prior to release, the perforation walls may provide an isolation layer and/or the isolation layer may have the perforation walls.
Cut initiation and the early cut performance may be enhanced in embodiments having windows 2709 placed in desired locations around the tissue specimen. For example, due to the mechanical load and electric field distribution of the wire(s) 151, the active electrode wire(s) may preferentially begin cut initiation at a first portion of the bag side walls. Placing a window 2709 at or near the first portion will enhance this initiation. Placing a wall at or near a second portion, in contrast, moves the cut initiation towards the second portion. By contrast, placing a perforation wall at or near the first portion may restrict the cut initiation at the first portion, unless the voltage created on the active electrode wire 151 can create an arc through the perforation wall. The windows and/or perforation walls may thus be configured such that a selected portion of the bag will provide the first portion of the tissue being cut.
That is, the cut may be controlled so as to travel from a first region of the tissue to a second region of the tissue.
Turning now to
With brief reference to
Turning now to
The apron 2885 may have one or more pouches 2881 to temporary hold proximal portions or connectors of the wire sets.
Those skilled in the art will understand that the apron may have benefit with any feature located on the bag surface that can interfere with loading of the specimen, and/or may be a benefit to protect during the loading, manipulation, exteriorization or other procedural steps. In some embodiments, an apron 2885 may isolate or protect an electrode or wire 151 as previously described, a mechanical member such as a wire, cable or mesh, a protrusion of the bag surface, monitoring electrodes, temperature sensors, pressure sensors, features embedded into the bag, and/or other items that are located in the bag, placed in the bag or used in proximity of the interior surface of the bag.
The apron 2885 may also be used as a containment flap 2986 (see
In some embodiments, the device 102, 200 may have a bag with a removable apron 2885. The removable apron 2885 may be selectively positioned interior of the bag and one or more cutting electrode wires 151. The removable apron 2885 may be movable relative to the bag to expose the wires 151.
In some embodiments, a drawstring 2987 is provided, and may be positioned or located at a bottom or distal edge of the containment flap 2986 to enable a user to close the containment flap and therefore capture the tissue specimen as well as contain fluids. This feature may be beneficial where the contents of the bag are desired to be contained during manipulation and exteriorization of the bag, such as where the tissue specimen is believed or suspected to contain cancerous cells. The containment flap and drawstring may also protect the bag features during loading of the tissue.
In some embodiments (see
After tissue specimen loading, the containment flap 2986 may be used to assist in exteriorizing the bag opening. Using a drawstring 2987 that is coupled to the distal edge of the containment flap along the circumference, pulling the drawstring through the incision site will raise the distal edge of the containment flap around the tissue specimen and draw the opening toward the incision. The drawstring may close or substantially close the containment flap and guide it through the incision. The bag opening may follow as it is pulled through the incision opening. When the bag has reached it intended exteriorized position, the bag can be secured with a semi-rigid member 2889 around the opening, can be inflated to secure or can be held with other mechanical means including being held in place by an attending surgeon. The drawstring can be loosened and the containment flap can be spread and/or cut to provide access to the bag features on the interior surface, such as electrode(s) and or wire(s) or wire connectors.
In some embodiments, a separate means of exteriorizing the bag can be used so that the apron 2885 can remain in place until after exteriorization. The bag can be exteriorized by coupling a lead or suture 2888 (see
In some embodiments, and as is illustrated in
A method to hold the distal portion of the apron against the interior surface of the bag is to weld or heat seal small locations around the circumference of the bag. These welds are designed to hold the bag in place but easily break free when the user applies a force to remove the apron. Additionally, a larger portion of the distal apron can be welded to the interior side of the bag with perforations added to the apron to allow it to be torn away by the user.
In some embodiments (see e.g.,
In some embodiments, the bag has a pocket with an opening on the top and a slot along the side so that the wires can be placed in the slot and the connector placed into the pocket.
In some embodiments, the location of the pocket is selected to align with the connections on the segmentation instrument to enable connection. In some embodiments, a pouch, pouches, pocket, or pockets are placed slightly below the proximal bag opening such that they remain under the apron to protect the connectors during insertion of the bag, loading of the tissue specimen and/or exteriorization.
One advantage of the apron is that it keeps the wires and connectors out of the way during loading. Multiple and different aprons might be used to cover different wire sets where one apron can be removed first to expose one or more connectors for connection to the instrument before a second apron is removed to expose one or more other connectors. In another embodiment, one apron may have openings for the wire connector(s) to allow connection to the instrument while keeping the wires out of the way and avoid inadvertent wire tangling. In this embodiment one or more first aprons with the connector openings may cover the wires while still allowing access to the connectors, while one or more second aprons could be used for the primary purpose of protecting the connectors prior to connection with the instrument.
The bag may include an additional guide that contains common sets of wires so that they maintain alignment near the bag opening above the perforations. The guide may include a heat shrink, tubing and/or other means to hold wires that are crimped or attached together in a common wire connector in close proximity. One or more guides may be used at locations along the wire(s) in which the wires can perform as intended if they are held together, such as above the perforations at a location near the wire connector.
With brief reference to
The guide may extend from a position proximal the bag opening towards the point at which the wires need to separate to be routed to their corresponding wire channels. This distal termination of the guide should be selected to not create undo tension of the wire so that it will naturally remain in close proximity to the bag inner surface as it exits the wire channels and also should not interfere with the tissue loading or the process of applying pre-tension to the tissue while advancing the introducer tube.
Some embodiments for guiding the wires near the bag opening may include an extended wire channel. This may be used independently or in conjunction with the heat shrink or other means of capturing the wires as previously described. The extended wire channel may be comprised of two polyurethane films that create narrow channels for the wires to be placed in during manufacturing. The films may be extensions of the wire channels attached to the inner surface of the bag and they may be attached or not attached to the inside surface of the bag above the perforations.
In some embodiments, a common film that is attached to the side wall of the bag up to the height of the maximum tissue specimen and free of the inner surface of the bag above this location may be provided. The connector(s) may be pulled out of the bag for ease of connection to the segmentation instrument, while still maintaining containment of the wires between the wire connector and the wire channels on the bag.
In some embodiments, the two film layers are attached together by RF sealing, welding, and/or any other means to form a lumen where containment is desired. In some embodiments, perforations are provided to allow the wires to be released from the guide by the user. The films can also be designed with a thin inside film layer such that the user can “tear” the wires through the film prior to applying the pre-tension, thereby allowing unrestricted travel of the pre-tension introducer tube into the incision site in preparation for the cutting procedure.
In some embodiments, an extended wire channel is located underneath an apron, with the proximal termination near the connector temporarily attached to the inner surface of the bag. This attachment may be with a heat sealed connection that is designed with a perforation for the user to tear away when making the wire connection, may be a thin film such that the user can “tear” the extended wire channels away from the inner surface of the bag, may be attached with a slot in the side of the bag in which the extended wire channel is seated during manufacturing, and/or other methods of attaching this channel to the inner surface of the bag. In some embodiments, the attachment may be made with the wire connector by the use of a pouch or region of the bag near the opening in which the connector is placed during manufacturing in which the user can remove during wire connection.
The shape of the extended wire channels can be designed or configured to reduce the chance of twisting the wires when released from inside the bag. In some embodiments, a relatively wider extended channel may be provided. In some embodiments, a plurality of wire channels are provided and aligned in parallel on the same extended wire channel. The width of this extended wire channel resists the twisting of the wires as the user makes the connections. In some embodiments, Mylar strips or other material is attached to the wire channel film to enhance this anti-twist feature. In some embodiments, Mylar strips or other material is placed between the outer layer and a third layer of film so that the extended wire channel naturally stays aligned in the proper position.
Some embodiments provide separate channels within the segmentation instrument. For example, a tray that also aligns the tensioning mechanism during cutting may provide separate channels. Keeping the different wire sets separate within the instrument eliminates potential tangling or interfering with each of the different wire sets as they are tensioned and as the cut progresses.
The guide structures previously described become particularly important if the wire length is designed to allow a long separation of the wire connector to the specimen bag after exteriorization, or if the connections are fixed to the tensioning mechanism such as described in Applicant's co-pending U.S. patent application Ser. No. 14/805,358, the contents of which are incorporated herein by reference in their entirety.
In some embodiments, the return electrode cable extends from the distal portion, or bottom, of the specimen bag along the inner side wall of the bag and out of the bag opening. A means to ensure that the return electrode cable does not interfere with the wire sets is important to ensure unabated cutting. This return electrode cable can be separated from the wire sets by routing the cable in a location between wire sets under a return electrode cable “wire channel” composed of a polyurethane film in a similar manner as the wire channels that contain the wire set channels by bonding the cable to the inner side wall, or can be routed between layers of the polyurethane film or can be created by depositing conductive material on the bag surface with an insulation layer added to ensure electrical isolation.
The segmentation instrument may include an indication on the exterior surface that visually aligns the orientation of the instrument to a specific feature on exteriorized portion of the specimen bag. This allows the user to keep proper alignment during connection of the specimen bag wire connectors to the segmentation instrument. The alignment feature can be a label, an inserted feature, an overmolded feature, a molded feature in the housing, a silkscreened shape, a shape with a similar color, a registration number or other symbol or other means of identifying to the user. Some embodiments may include a contrasting line applied axially to the exterior housing of the distal tube such that when the line placed in alignment with the return electrode cable, the instrument is in proper alignment with the specimen bag for wire connections to be made.
With the introducer tube extended into the specimen bag and against the tissue specimen, any slack within the wires is removed and a tension is applied to all of the wire sets. This tension aligns the wires from the distal end of the introducer tube to the wire connection point inside the segmentation instrument. This alignment ensures that each wire set can advance within the instrument without interfering with the other wire sets. Without this alignment, the chance of a non-activated wire set catching or tangling with the wire set being cut increases.
Turning now to
The inflated cells 3132 provide an additional thermal insulation barrier between the tissue specimen or electrode and the adjacent structures outside of the exterior surface of the removal bag. In contrast, if the entire bag is inflated as a single cell, failure of one of the layers would cause the inflation and thermal insulation to be lost. By providing multiple independent inflation areas 3132 in the bag 3130, if one of the layers in an individual region fails, the thermal insulation of that layer may be lost or reduced; however, the remaining inflation cells 3132 will continue to provide thermal insulation, and minimize any thermal damage caused to the patient.
With continued reference to
In some embodiments, inflation features or functions are integrated within the wire channels. For example, a third layer may be provided at the channels. The first layer is the perforation layer, the second is a boundary layer and third is a bottom layer. The boundary layer and bottom layer are sealed so that when low pressure air or fluid in applied, the channel will inflate providing structure directly beneath the wire channels. This has a benefit in providing thermal insulation directly beneath the wire as well as helps provide structure which aides in release of the wire from the channels.
Turning now to
In some embodiments, a piezoelectric crystal or piezoelectric stack of crystals 3202 is coupled to an end of the tensioning mechanism 3204 which may include a spring 3206 or other means of applying a mechanical load. As illustrated, an active electrode wire 3208 may be mechanically connected on an arm 3212 that vibrates perpendicularly to the tensioning mechanism 3204. The vibrating arm 3212 may be acoustically coupled to the piezoelectric crystal 3202. The crystal 3202 may use an ultrasonic horn 3214 or coupling to amplify the displacement, and may be oriented such that torsional motion in the ultrasonic range causes vibration axially or longitudinally along the electrode(s) or wire(s).
A control system may be applied to the electrodes of the piezoelectric crystal to drive the oscillation at the optimal frequency. The control system may utilize a phase-locked-loop to control to an optimized frequency that provides the highest ultrasonic power transfer through the wire and into the tissue. The phase-locked-loop may also have an amplitude modulated gain stage designed to maintain oscillation from the lowest force applied to the highest force applied by the tensioning device. Other control systems may be utilized such as a Wein-bridge oscillator or a fixed oscillation that does not maintain constant displacement used as a compliment to RF energy cutting.
In some embodiments, an introducer (see
Turning now to
Those skilled in the art will understand generally that initiation of the wire to begin the cutting effect results from a separation between the wire electrode 3302 and the tissue when power such as RF energy is applied, and that coating on the wire electrode or a film material in the bag 3304 or any other component may be suitable for achieving this effect.
In some embodiments, a separate means to pre-tension the tissue sample and an insulative layer between the wire electrode 3302 and the tissue are provided for this purpose. This layer may be a pressurized air layer, a non-conductive fluid layer, an insulating film or layer applied between the wire and tissue, which may serve the alternative function of applying the tension of the tissue sample, or could be achieved with the design of the bag, the wire attachment, and the pre-tension mechanism such that a gap results in the tissue wire/bag interface during operation. The desired wire set to be activated may have power such as RF energy applied and after sufficient power having a voltage is applied, the wire set may either be pulled to the surface of the tissue or may mechanically, electrically or with temperature break through the separation layer and begin the cutting effect. Generally stated, any easily electrically removable (or degradable) adhesive or retaining volume to hold the wire electrode in place may be provided, as illustrated in
Turning now to
One additional advantage of the return electrode 3420 is that the bag assembly will more easily compress to a small diameter to aide in insertion through the incision site.
In some embodiments, and as is illustrated in
The dual return electrode 3540 may be configured to collapse against the introducer allowing easier insertion, while providing a large surface area 3549 when the tissue is loaded and tension is applied to the bag. Those skilled in the art can see that the number of recessed areas 3542 and the ratio of return electrode surface area 3549 to recessed areas 3542 can be adjusted to ensure the surface area 3549 remains large enough to maintain lower return electrode heating during power activation, and case of collapsing during insertion of the bag into the incision site.
Methods of making a return electrode such as those described herein may include bonding a return electrode and cable to the bag, or forming the electrode on the surface of the bag with a vapor deposition, spray coating or a conductive printing process. A deposition or conductive printing method may provide improved flexibility of the finished bag to allow easier insertion. Bonded return electrodes and return electrode cables may be made from flexible circuits bonded with adhesive, or may be integrated into the bag layers by heat sealing at the boundary of the cable and/or return electrode.
In some embodiments (not illustrated) tissue segments may be marked for identification through the use of power modulation of each wire or wire set, such as providing a different power setting or waveform so as to leave a characteristic desiccation layer or pattern as part of the segmentation cut. This different power setting or waveform may be a modulated higher frequency waveform that is combined with the fundamental waveform delivering the RF power to the tissue. As such, the primary function of controlling the RF power delivered to the tissue to perform the cut can be relatively unaffected by the modulated waveform by the use of an analog or digital low pass or band pass filter in the control system feedback loop. That is, the method 10000 may include adjusting a power setting so as to cause the wire to leave an identification pattern in the cut associated with each of wires 1-N. In some embodiments, the identification pattern may be different for each wire, or some wires may have the same identification pattern as others (e.g., some may simply identify a direction, or which wire was the first or last, etc.).
Turning now to
With reference now to
With continued reference to
In some embodiments, a first ring of material 1006 may have a longitudinal dimension that is different from a second ring of material 3708. In some embodiments, the first and second rings of material 1006, 3708 have a conductivity that is different from the rest of the coating 3702 on the electrode 3716. In some embodiments, the rings of material 1006, 3708 are more conductive than the rest of the coating 3702. In some embodiments, the rings of material 1006, 3708 are less conductive. In some embodiments, the first ring 1006 has an overall surface area that is different from an overall surface area of the second ring 3708.
In some embodiments, the length of the insulation material 3704, the number of bands for a given length, and/or the spacing of the bands 3704 may be modulated so as to sufficiently identify cuts made by the respective active electrodes. In some embodiments, the bands may, instead of an insulating material, have a highly conductive material that conducts current at a higher rate than the normal coating 3702 on the active electrode surface. That is, generally speaking, the identification bands 3704 may be more or less conductive than the coating 3702.
In a tissue segmentation method, a surgeon may pre-mark the tissue specimen during loading or after the bag is exteriorized.
In some embodiments, an ink stamp may be provided on the proximal tissue specimen surface when the bag is exteriorized, can be an ink stamp marked during loading, or can be dyes injected into regions of interest into the specimen prior to cutting.
Returning briefly to
The receptacle of the tensioning mechanism designed to connect to the active electrode wire connector may have a color or shape associated with it. The corresponding active electrode wire connector may have the same color or shape allowing the user to connect the like colors or like shapes together ensuring that the proper sequence will be maintained. In some embodiments, a method of ensuring the proper connection sequence is maintained includes providing each of the tensioning rod receptacles with a unique shape such that it will accept only the corresponding active electrode wire connector having a unique mating shape. Alternatively the respective wires may have increasing amounts of coating impedance from one wire to the next. Energy may then be applied to all of the wires, however the coating variation will force the wires to fire or cut sequentially rather than simultaneously.
In some embodiments, the spring 676 is used as a direct electrical conductor to apply the power or RF energy to the wires, and insulation coatings may be applied to the surface of the spring to control when power application can be enabled. Locations of this insulation material can be applied so that when the spring is in the fully extended, or pre-tension, position an insulation coating is located at the contact point of the power or RF energy to spring electrical interface. When the device is pre-tensioned and the springs advance to apply the tension on the tissue sample, the insulation coating advances to the coil of the spring and an electrically conductive portion of the spring is now in contact with the RF to spring electrical interface. An additional insulation coating can be applied at the location in which the spring completes its cut so that power or RF energy is terminated.
Some organs for specimen cutting include but are not limited to: uterus, ovary, kidney, colon, spleen, liver, gallbladder, and lung. For some organs, the minimally invasive access and excision of the specimen may benefit from a noncircular distal instrument end such as in video assisted thorascopic surgical procedures (VATS) for lung. In this case the incision may be much wider than it can be tall because of spacing between the ribs. In this case it may be advantageous for the segmentation instrument to be non-circular to accommodate or optimize use of the space available. For example, more than two tensioning mechanisms may be generally arranged in a line within an oblong oval shaped instrument end. The shape of the bag may also be modified to better align the electrode wire assemblies with the tissue specimen shape and size. This may also require a different number of active electrode assemblies or different active electrode wire lengths.
In some procedures, it is likely that the specimen may contain a staple line or clip remaining from an excision. This is particularly common in lung and colon procedures. It may be desirable to utilize a stronger wire that is more likely to penetrate the staple line during the cut without breaking the active electrode. This may be accomplished through use of a stronger material, titanium as an example. It may also be accomplished through the use of a stranded wire or a larger diameter wire than would be typically used.
As technology advances and drives more minimally invasive procedures, the incision sizes commonly used in surgery continues to reduce. As these sizes become smaller, the need to remove tissue specimens that are routinely removed with currently available methods becomes more of a challenge. In addition to the organs previously mentioned that are candidates for specimen cutting for removal, smaller portions of these organs and small masses that are not considered necessary for tissue segmentation prior to removal will become candidates for removal in the future. An example could be an appendix or gall bladder that can easily be removed through a 5 mm trocar today, but as the use of 3 mm devices or smaller become more commonplace, segmentation of the device will become an obvious solution for removal.
In some embodiments, a crimp connector including a resistor, optical feedback or RFID that that has corresponding circuit in the tissue segmentation device 100 or the controller 108, 708 may be provided that may perform an identification method. In some embodiments, the identification method includes: (a) identify to the controller a particular length of exposure, to notify the controller of proper power setting (controller can adjust if different length exposures are used); and/or (b) identify to the controller the type of bag being used. The identification method may include distinguishing or identifying the use of a small uterine bag, a large uterine bag, a lung bag, a colon bag, a kidney bag, etc. The bag identification method may be achieved using the resistor value, optical signature or RFID as an index for a lookup table pre-programmed into the datastore 110 of the controller 108 or device 102. The index may point to stored parameters that update the parameters for the particular type of bag or the specific active electrode wire set connected to the connector containing the resistor. In some embodiments, the information programmed in the optical encryption or in the RFID contents is used to update the parameters with the information passed to the controller 108. This information may, in some embodiments, include the sequence number so that the controller is configured to apply RF energy in the correct sequence for any connection made by the user or may contain impedance or other performance information that can be used as an adjustment to parameters for that particular active electrode wire set.
Turning now to
In some embodiments, the crimp ferrule 3906 has a stepped feature at a proximal end such that the crimp ferrule 3906 is fixed in or relative to the crimp connector 3905. This provides mechanical and electrical coupling between the crimp ferrule 3906 and the crimp connector 3905. The resistor 3901 may be placed within the crimp connector 3905 such that the distal end cap 3909 is electrically in contact with the end crimp ferrule 3906. This provides an electrical coupling from the outer surface of the crimp connector 3905 to one end of the resistor 3901.
Of note, the proximal end cap 3910 is electrically isolated from the crimp connector 3905. This is achieved by creating an isolation barrier 3908 that may be provided by, for example, an insulative film between the resistor 3901 body and the internal surface of the crimp connector 3901. This may be an insulative film or coating applied to the top portion of the inside surface of the crimp connector, an insulative film or coating applied to the sides of the end caps 503, physical separation provided with end caps that have a smaller diameter than the resistive element or by placing the resistor within an insulation component that exposes only the center of the top end cap prior to inserting into the crimp connector.
In some embodiments, a resistance value of resistor 3901 can be electrically measured between the proximal end cap 3910 and the outer surface of the crimp connector 3905.
With continued reference to
Turning now to
Here, the component (not shown) within the tensioning instrument that interfaces to the crimp connector 4021 has a separate contact point on the inside mating surface at the proximal end and must be electrically isolated from the lower portion. The resistance of the resistor 4020 is then measured by applying a known voltage, or current, between the proximal contact point and the outer portion which contacts the remaining surface of the crimp connector and measuring the resulting other one of current, or voltage.
Measuring the resistance can be achieved using an analog circuit, such as an op amp or other means to apply the reference voltage or current and an A/D converter to measure the resulting electrical parameter. This circuit can be located within the tensioning instrument or can be located within the controller.
Separate electrical traces may be provided to each side of the resistor 501, 4020 and may be accomplished by applying a thin conductive trace on the surface of the spring isolated from the spring with an isolation film. The conductive trace may be routed to either the axial contact (see
In some embodiments, the electrical traces are provided by using separate contact areas on outer surface of the termination block that are routed to either the axial contact illustrated in
Returning now to
A second type of bag also with 4 active electrode wire sets may contain 1100 ohm, 1200 ohm, 1300 ohm and 1400 ohm resistors respectively. Using this approach, those skilled in the art can see that many number of bag types with varying combinations can be supported with a controller that contains the lookup table information.
In some embodiments, the system is configured to perform a tissue to return interface impedance check. Those skilled in the art will understand that it is essential to have good contact between the tissue specimen and return electrode of the device to maintain low temperature cutting. One method to ensure this contact is described in the open circuit check previously described herein. Another method is to utilize two sections of the return electrode in a manner similar to methods known in the art. Using known methods, a small interrogation signal is applied by the electrosurgical generator between two sections of the return electrode. This signal is used by many currently available generators to calculate the impedance between the two return electrode sections. As the tissue makes contact with the two sections simultaneously, the impedance of the tissue between the sections will provide a low resistance. This is continuously monitored by the generator, and if the tissue loses contact with the return electrode, the impedance change can be observed and an alarm condition can be initiated so that the user can address the situation.
In some embodiments, a movement/position indicator is provided. Graduated markings on the surface of the spring in conjunction with an optical encoder or transceiver pair allows relative measurement of spring travel. A rate of electrode/wire travel may be detected by integrating over a time period a length of travel. The length of travel may be determined by counting markings from a pre-tension location. A stopped travel condition may be identified and indicated by a lower than acceptable rate of travel.
Turning now to
Applicant has determined that as the tissue is segmented with multiple power or RF energy activations of the system 100, the structure of the tissue is weakened and the tissue “flows” or changes shape, which can cause irregular or non-repeatable segment sizes to occur. A method of reducing this tissue flow may be provided, and may include holding the tissue during segmentation to contain the flow.
For example, and with reference to
Returning now to
Some methods and/or systems improve the reliability of the cut by pre-treating the tissue sample prior to cutting, such as by applying cryo to freeze the tissue. This may provide a more rigid specimen, and may reduce the thermal result of the cutting. Some methods include injecting a fixation material into the tissue specimen, which increases the rigidity of the specimen.
In some embodiments, a tensioning mechanism may include a constant force spring 702 and/or other mechanisms such as a pulley system, a cable drive or winch system, non-linear springs, linear drive with rotational coupling such as gears or contact coupling, linear drive with magnetic coupling, linear drive with manual control, and/or, as previously described, an electromechanical drive, such as a servo or stepper motor drive or linear actuator.
In some embodiments, a method of preparing or examining a tissue specimen is provided. One method for marking and reassembling the tissue specimen for later pathology involves the surgeon marking the margin or area of interest for later pathology prior to or just after placing the specimen in the bag. The surgeon can then segment the tissue and remove the pieces from the bag. Once removed, the specimens can be reassembled or the marked pieces may be identified and examined for pathologic assessment. The marked specimens may be identified through visual examination or may contain a fluorescing or similar chemical marker to enable the user to identify the segments using a fluorescing light.
Turning now to
In some embodiments, the distal end 4404 has a relatively long inked exposure 4408, such as up to between about 6 and 8 inches (between about 15.24 and about 20.32 centimeters) in length for marking a large surface of the specimen quickly. In some embodiments, the entire distal end 4404 may have an exposure 4408. In some embodiments, the exposure 4408 is less than the entirety of the distal end 4404.
Alternatively, in some embodiments, a relatively small exposure 4408 may be provided, so as to control the placement of ink in a more refined or selective area. Those skilled in the art will understand that the length of the exposure 4408 may be adjusted or selected based on a number of factors, including, but not limited to, specimen size, patient size, surgical cavity size, specimen location, and/or other factors. In some embodiments, the marking tool 4400 has an articulating link 4410, to allow articulation of a distal end 4404 relative to a proximal end 4412, to facilitate specimen marking.
In some embodiments, the specialized marking tool 4400 may have a means for expanding a diameter of the distal end 4404 once inserted into the patient, and decreasing the diameter prior to removal from the patient, and in some embodiments back to the original diameter prior to removal from the body. In some embodiments, an inflatable balloon 4414 that contains the ink on its outer surface may be provided. The user may inflate the balloon 4414, mark the area of interest on the specimen, deflate the balloon 4414, and then remove the marking tool 4400 from the body. The balloon 4414 may be contained within a shaft 4402 of the marking tool 4400 and extended from a distal end of the shaft 4402 prior to inflation of the balloon 4414. The ink may be present on the expanding member prior to insertion into the patient or may reside in a small pouch within the instrument whereby the user expands the marker and then breaks open or releases the ink so it can then be applied by the expanded member.
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In some embodiments, the bag 4500 may be manufactured with the ink 4502 in one or more relatively small ink pouches 4506 that are attached to the bag 4500 during manufacturing. Alternatively, the ink pouch(es) 4506 may be empty and built into the bag 4500 with the ink injected into the pouches 4506 by the surgeon before or during use through a channel opening on a distal end of the bag. This has the advantage of allowing the surgeon to select what ink or marker he or she prefers. In some embodiments, one or more ink pouches 4506 may be attached to a return pad 4504 of the bag 4500. In some embodiments, one or more ink pouches 4506 may be attached to a flexible container 4512 of the bag 4500. In some embodiments, a plurality of ink pouches 4506 are attached to both the return pad 4504 and the flexible container 4512.
Turning now to
In some embodiments, the clinician may apply markers after the segmentation but prior to removal of the segments from the bag. Marking of the samples may be done with a surgical marker, ink 2314 (see e.g.,
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In some embodiments, the surgeon may mark the surface or portion of the specimen that needs pathologic assessment for margin, prior to or just after loading the specimen in the bag. This may be done with a marker or ink. The specimen can then be segmented, and removed from the patient. The pathologist then knows to find the segments that contain this surface and to assess for margin or any cancer cells that might be found on the surface.
Some embodiments include using imaging recognition, including but not limited to, a digital camera and/or ultrasound to image the specimen prior to segmenting, removing, or during removal of the segments from the bag. Digital image processing may then be used to reorient the segments in order to recreate the specimen using software designed to recognize features on the segments and reorient them in the proper location relative to each other. A low cost digital camera with digital imaging software may likewise provide an inexpensive and automated means for reorienting segments into their original orientation. This may be done with or without prior marking of the specimen before imaging.
Some embodiments include reconstructing the excised tissue specimen after removal, and to use a common imaging means, such as fluoroscopy, on the segmented tissue specimen to determine the location of the area of interest within the tissue specimen. This may also be used to perform additional diagnostics on the specimen to determine the scope of pathological assessment required or to guide the remaining surgical intervention required.
In some embodiments, markers may be used to identify a known tumor or structure of interest either before surgery or intraoperatively. The bag may also have markers or fiducials that can be imaged or scanned as part of the loaded bag in order to show the orientation of the specimen (and tumor) relative to the bag. By tracking the specimen segments as they are segmented and removed the known original location of the tumor, and thus the segments that contain the tumor, may be determined. This provides further information to the pathologist during their evaluation.
In some embodiments, the wires may be used as the fiducials prior to the cutting. To further enhance their location an ultrasound sensitive or radio opaque coating may be applied to a small portion of the wire. Using commonly available image capturing approaches the location of the wires, their projected path of travel, and the location of the tumor can all be determined and analyzed. This information can then guide the pathologist on which segments have particular interest for pathologic assessment. The surgeon or operating room staff may place additional markers on the tissue segments prior to leaving the operating room using this image information to identify segments of interest. The images from the specimen taken with the wires or bag fiducials that estimate the segments can also be accessed during pathology to show assembled segment structures (i.e. vasculature, tumor, etc.) that can be compared to the segments themselves.
In some embodiments, a method of cancerous tissue handling is provided. During removal of segmented tissue that is known or suspected of being cancerous from the segmentation bag, extra care may be desired to ensure that fluids or tissues do not spill and thereby cause specimen site seeding. Various methods such as an absorbent pad 4708 may be used to limit spilling of tissues. The pad 4708 may have a hole in it that is placed over, under or around the exteriorized bag opening 4710, to absorb any fluids that may spill (scc e.g.,
With reference to
In some embodiments, and as illustrated in
As illustrated, the elongated bag 4700 may have a flexible container that is twistable at one or more twisting regions 4706 so that individual segments 4704 may be captured individually. For example a segment 4704 may be captured, the bag 4700 may be twisted to contain the segment 4704, and the process repeated with another segment 4704 placed in the bag 4700 (note this twisting process applies to the secondary bag 4700). Those skilled in the art will understand that even where an elongated or secondary bag 4700, 4700 is provided and enables a user to twist tissue segments 4704 to separate them, the user need not necessary perform this step, optionally capturing all tissue segments 4704 in a single cavity. Those skilled in the art will also understand that the user may optionally seal, tie, clamp, or otherwise fasten the twisted regions 4706 so as to semi-permanently separate the individual segments 4704 from one another. In some embodiments, the film 802 previously described herein may provide a semi-permanent sealing feature between the cavities formed about the segments 4704.
With novel dyes being created for use in identifying cancerous cells in situ, these dyes may be placed in the bag, so once the specimen is segmented, the surgeon can look at the bag to see if any signs of cancer are present in the sample. For example, in a method similar to fluorescence-guided surgery using a cancer cell “homing device” and imaging agent created by a Purdue University researcher, novel imaging agents may be injected prior to surgery, and could be seen in specimen upon removal. Relatedly, a similar imaging agent may be placed in the bag (bag wall, small pouches on bag return, or injected into bag by surgeon with a syringe or similar instrument prior to or after removing segments from bag) in a manner substantially as previously described herein with reference to
Turning now to
As previously described, a wire or electrode coating may be provided to enable tissue segmentation at a relatively low power and low temperature, with a relatively quick initiation of a tissue segmentation cut.
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Turning now to
In some embodiments, an emergency release of the wire connectors from the instrument is provided. The emergency release may include a clamp or “brake” associated with the spring(s), which allows the device to be pulled away by a force exceeding the force or strength of the wires, causing them to break.
The emergency release may include pushing the insertion tube against the tissue so that it extends beyond the range of the wires, causing a higher force on the wires, which ultimately breaks the wires or connections. The emergency release may include the use of a nitinol spring or clip in the wire crimp barrel that releases the wire crimp from the connector barrel. The emergency release may include a member or release feature configured to apply a force from behind that re-extends the springs to the position prior to tensioning, to allow the user to remove the connectors, retract the distal insertion tube and insert a component that can couple to the springs and pull them forward allowing disconnection by the user. The emergency release may include an aperture that, when collapsed, constricts around the wires severing the connections. The emergency release may include a connector system in which a magnetic coupling retains the connection, wherein removal of the magnetic field causes the connectors to separate. The emergency release may include a release feature integrated into the device, such as a lockout collar that is rotatable to extend the spring back to the original position, such as after having moved the spring by rotation in a different direction.
In some embodiments, an emergency release is provided with a tensioning rod designed with a release force just above the maximum range of intended use, and where the connection point either separates or collapses when the applied force exceeds a trip point or the maximum range of intended use. In some embodiments, the segmentation device is configured such that the user may apply a higher force away from the patient, and the tensioning rods are configured to release in response, such as when the higher force reaches a trip threshold or maximum range of intended use.
In some embodiments, a lock feature is provided on the tension rod that opens jaws that hold the connector when force is lost after tensioning is started or with a user initiated control. The lock feature may be used in conjunction with a brake and a relaxation of the force by pushing the device into the patient to release the connectors.
In some embodiments, a cutting feature is provided on the tensioning rod, and configured to cut the wires upon user initiation, such as a knife edge or a pinch point that moves to contact the wires.
In some embodiments, an eject feature on the tension rod is provided and configured to eject the connectors at user initiation, lift gates that sever the wire at the distal end of the tray, electrical excitation, such as a different resonant frequency or energy level, to melt, drive a phase change, soften or release a retainer pin, a pinned connector rod pin pushed out from the back to release.
In some embodiments, and as illustrated in
Turning now to
In some embodiments, an emergency release including a “jack” engagement is provided, wherein the tensioning rod has a raised portion that aligns with an open portion of a flat spring on the wire connector. The wire connector is pushed onto the tension rod until the open portion of the wire connector captures the raised tensioning rod. The flat spring on the wire connector extends distally beyond the tensioning rod and has a raised shape that will interfere with features in the lumen of the instrument if reverse force is applied. This reverse force can be stepped features molded, machined or added to the lumen interior surface or can be provided by strips of an interior tube that can only interfere with the spring if rotated to the “release” position, thereby only allowing release when the user actively enables that feature.
In some embodiments, an emergency release of the tensioning mechanism and/or other components is provided by way of a detent connection. For example, a movable protrusion in a first component and biased towards an extended position may be provided and configured to selectively engage a recess or passage in a second component. The detent connection may be configured to selectively release in response to a tripping force or an override input.
Turning now to
In addition, parallel sections of the spring that are electrically conductive but not electrically coupled may be incorporated on the spring surface. In some embodiments, this effect is created with the application of a thin conductive layer with an insulated backing. By the addition of these electrical “traces”, separate contact members may be provided that aligns with these traces to allow different electrical signals to be coupled along the length of the spring without interference. In some embodiments, the resistance values from the electrode wire resistors are supplied to a circuit within a fixed portion of the electrosurgical instrument 102, to identify the type of electrode, such as in a manner previously described herein.
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Embodiments disclosed herein may be used in polypectomy, dissector, or other applications where wire cutting with coagulation or hemostasis is desired.
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During low temperature, rapid wire cutting applications, the delivery of energy where some level of hemostasis is desirable may be altered to provide both hemostasis as well as rapid cutting.
One means to increase hemostasis is to alter how energy is applied initially during a wire cut. A voltage limited power, with a low voltage and higher current capability, may be delivered initially to the tensioned wire cutter so as to delay the cut initiation and allowing coagulation of tissue prior to cutting. At a predetermined time or until a predetermined parameter threshold is met, the energy delivery could then be altered such that the wire cutting is initiated through increased voltage. Another means to accomplish this would be to initially apply a non-sinusoidal waveform to enhance the coagulation effects and to transition to a sinusoidal waveform to enhance cutting. This can be a single event or can be continuously adjusted as the cut advances. This may also be adjusted by modulating between a pure sinusoidal waveform and a higher crest factor waveform based on feedback from electrical or rate of travel data to improve control and the cutting performance. This modulation can be pulse width modulation, changing distortion characteristics of the waveform, elimination or changes in amplitude of cycles or partial cycles of the output, changing dampening characteristics by adding or subtracting loads on the RF output stage, or other means.
Parameters that may be of interest to monitor include electrical parameters such as impedance or phase change or mechanical parameters such as tissue shrinkage or compliance. During the initial hemostasis step a higher force may be applied to the wire during coagulation than is required for the cutting alone with pressures as high as 100-200 psi. The force may then be lowered or maintained to complete the cutting. Coagulation or hemostasis times may vary, but times are expected to be between 0.25-10 seconds. Wires may or may not have high impedance coatings or alternatively a nonstick coating depending on the application.
Turning now to
In some embodiments, it may be desirable to reliably close a removal bag, such as for lap to vaginal removal. For example, in some embodiments, a bag sealer tool may be provided to seal the bag opening by melting the bag together. Here, material having a relatively lower melting temperature may be provided at the opening end of the bag for more reliable, casier sealing. In some embodiments, a large clip or tie may be provided to enable a reliable closure. Here, the user may apply the clip or tie over or about a malleable material (such as a wax and/or adhesive) area or strip that is permanently attached to the bag opening to provide a fluid impermeable barrier between the contents of the bag and the exterior. The malleable material may be provided on an interior or exterior wall of the bag. Providing the malleable material on the exterior of the bag may reduce the potential or accidental pre-engagement, with engagement made possible after, for example, the user flips an end of the bag in. In the alternative, a removable strip on the malleable material may be provided, so as to prevent pre-engagement.
Turning now to
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The robotic grasper 8832 may include a camera on an arm 8835 to allow a surgeon to view the robotic grasper 8832 going in and out of a patient's body or incision. The guide means 8834 provides the ability to guide the robotic grasper 8832 in and out of the incision or a trocar including a guide between the trocar or incision site. In some embodiments the robotic grasper 8832 is configured to travel between the incision site and another location (such as a specimen or pathology container, or a tray to receive tissue).
The bag-machine interface 8836 may be provided on or proximal to the bag opening, and is configured to interface with a robotic arm 8838 and allow the arm 8838 to provide tension on the bag 8831 during removal of the tissue segments 8822 such that the segments are easily identified and grasped.
Some embodiments disclosed herein may be used for removing lung tissue. For example, a surgical method provided herein includes (not necessarily in this order): (1) Mark or identify margin or area of interest for pathology (optional). (2) Insert specimen bag into thoracic cavity for specimen capture. (3) Load specimen in bag. (4) Exteriorize bag opening. (5) Connect wire connectors to instrument. (6) Insert distal end of instrument into thoracic cavity. (7) Pretension wires prior to cutting. (8) Segment tissue using either mechanical or mechanical/electrical cutting. (9) Remove instrument. (10) Apply external compression force on tissue segments at an angle between 15-90° to the direction of cutting or wire retraction pull force in order to decrease bag diameter and/or re-orient tissue segments. (11) Remove bag with contained specimen(s).
A tissue removal method disclosed herein includes (not necessarily in this order): (1) Mark or identify margin or area of interest on specimen for pathology (optional). (2) Insert specimen bag into thoracic cavity for specimen capture. (3) Load specimen in bag. (4) Exteriorize bag opening. (5) Connect wire connectors to instrument. (6) Insert distal end of instrument into thoracic cavity. (7) Pretension wires prior to cutting. (8) Segment tissue using either mechanical or mechanical/electrical cutting. (9) Remove instrument. (10) Remove specimen segments. (11) Remove bag.
The temporary holding of wires to the bag may be performed in several manners. Bags may include multiple layers, or single layers with additional features attached to temporarily hold the wires in place. The bags may include several film pieces welded or adhered together, or they may be molded by reshaping a film, or blown in a mold similar to a balloon. Regardless of the approach, the means by which the wires are held in place must be releasable and release in order to complete the segmentation of the tissue.
Another important feature of using wires to segment a specimen, either with or without radiofrequency energy, is to ensure that the wires are held to the side wall of the bag, as illustrated. By keeping the wire(s) temporarily attached to the side wall of the bag, the specimen may be loaded without inadvertently shifting the wire(s) or catching on the wires so the specimen can't be fully loaded. For this purpose, the wires may be held in place using loops, perforations or similar bag features that release with tension applied to the wires. In addition, the holding features may release in response to an application of energy to the wires that melt or soften the holding features. An additional approach is to have a mechanical pull or feature that the user can pull that releases the wires from the holding features. The mechanical pull or feature may be separate strings attached to the holding features that the user can access near the opening of the bag when exteriorized. Inflatable features within the bag itself may also be used to rupture the holding features.
One potential risk of temporarily attaching wires to the bag is that the bag ruptures during detachment of the wires. The use of multiple bag layers will help to ensure that the bag remains intact upon release of the holding features. The holding features are attached to the most inner layer of the bag, with one or more additional layers on the outside of the bag to ensure the bag remains intact and impermeable to fluids.
Additional features may be added that provide feedback to the user regarding bag integrity. The bag may be inflated or have inflatable channels. With inflation, the measured inflation pressure that the bag or inflatable channels holds is an indication of any possible holes in the bag. Use of a pressure valve with a sensor can be used to detect any drop in pressure. The pressure valve and/or means to inflate the bag or inflatable channels may be integrated into the bag or alternatively be integrated into the segmentation instrument itself. Other potential approaches include use of a camera to allow the user to view the outside of the bag during the procedure, use of a color changing indicator within the outer two layers of a three layer bag that changes color upon contact with bodily fluids, or use of clear outer bag layers or films where the user can visually determine if any fluids have penetrated between the two layers. Another method could be to have a conductive deposition on the inside of the outer bag layer and a center layer that is separated to the outer layer by the inflation. The capacitance between the two conductive layers can be monitored such that a drop in pressure will change the capacitance reading, similar to a capacitive touchscreen press. The capacitance can be measured at regular intervals, on command or continuously or a threshold can be predetermined such that if the pressure is lost, the system can identify the condition and issue an alert. The two conductive layers can also be used in a similar manner as a resistive touchscreen in that the change in resistance between the two layers can be used to indicate a loss of pressure condition. Lastly the outer two layers of the bag may contain a sterile fluid by which the user can be confident of bag integrity if the fluid level has not fallen during the course of the procedure.
If the user visually determines a void in the bag, an adhesive patch may be applied in situ to reduce the risk of bodily fluid or tissue loss from the bag contents. The user may also decide to wash (rinse and suction) the patient's body cavity.
Although this document primarily addresses electrosurgical systems, it should be understood that tissue segmentation and removal may, in some embodiments, but achieved using a segmentation device that does not have an electrosurgical component. Specifically, a surgical device having one or more wires that segment tissue mechanically, such as by force, motion, and/or vibration may be provided. Many of the examples disclosed herein also apply to such a mechanical surgical device. For example, a surgical device may utilize wire tensioning methods disclosed herein without the electrical aspects, and with or without a controller configured to control the pull forces or speed of cut. Similarly, the robotic system may also provide a cutting function that is not electrosurgical in nature. As in the case of the electrosurgical segmentation procedure, the removal bag may provide means for keeping the cutting wires in place (and from entangling with each other) while a tissue segment is placed in the removal bag, and, similarly, the wires may be configured to detach from the removal bag at a desired set force or time. The use of mechanical only cutting may be advantageous in applications where the tissues are not calcified, have less variability of mechanical properties, or are generally more friable, and therefore do not require extremely high forces to cut reliably through the tissues. To address this case, the tissue removal device or wire cutting device may be configured without the elements that are required for electrosurgical cutting; for example the return electrode or connections to the controller or an electrosurgical generator may be omitted. Those skilled in the art will understand that a removal device without the electrosurgical cutting elements requires a smaller number of user completed instrument connections. In turn, this may lower the production costs of the product. In some embodiments, a removal device that does not have an electrosurgical cutting feature allows for cutting tissue at a lower temperature, and may be a safer alternative for weaker patients. Those skilled in the art will understand that the mechanical pull force(s) in a removal device without electrosurgical cutting will be significantly greater than one with an electrosurgical cutting feature.
As was previously mentioned in U.S. patent application Ser. No. 14/805,358, there may be some benefits to a bipolar application of RF energy. Figure
As previously described herein, rupture of the bag 161 is a potential failure that should be monitored, prevented, and/or mitigated, whether with a tissue segmentation device or simply with a removal device that does not segment tissue.
With reference now to
In some embodiments, pressure in the space 9106 between the layers 9102, 9104 may be used to inflate the outer bag layer 9102. If a breach occurs in the outer bag layer 9102, the loss of pressure can be detected visually by looking for a decrease in inflated bag size or pressure.
In some embodiments, a vacuum may be applied to the space 9106 between bag layers 9102, 9104. The vacuum may serve two purposes: first, a vacuum may provide a visual indication of a breach if the outer bag layer 9104 no longer appears to be pulled towards the inner layer 9104. Second, if a breach occurs in the outer bag layer 9104, the vacuum will draw air into the space between the bag layers 9102, 9104 thereby minimizing the potential for other materials or fluids to escape the hole (in particular if the hole is small). That is, a vacuum in the space 9106 between layers 9102, 9104 may tend to bias an inward flow of fluid, whereas a pressure in the space 9106 would tend to, in the event of a breach, release fluid out and potentially into the patient.
In some embodiments, and as is illustrated in
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In some embodiments, a slight vacuum may be applied to the space 9106, 9306 between layers 9102, 9104, 9302, 9306 or the bag interior 9204, such that the content of gas being detected at the sensor 9202 is increased, thereby providing a more accurate indication of a leak. This slight vacuum may be created using a pump (not illustrated), evacuated air cylinder or other means to apply a negative pressure, including, but not limited to, an air flow control valve coupled with the sensor 9202 to draw the contents of the space 9106, 9306, 9204 toward the sensor 9202 and ensure that the negative pressure can be maintained throughout the procedure.
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This monitoring may establish a baseline and/or provide a more accurate indication of the starting level of CO2 and/or N2O. The sensor 9202 may, in some embodiments, monitor for differential or changing levels of CO2 and/or N2O as previously mentioned herein. In some embodiments, the bag system 9500, as illustrated in
The sensor 9202 may be used independently and/or may include a visual or audible indication when CO2 and/or N2O is detected. The sensor 9202 may also be electrically coupled to a processing unit such as the controller 108, 808 that can create an audible or visual indication to the user when CO2 and/or N2O is detected. The sensor 9202 may also be electrically coupled to the instrument 102 or may be coupled to a separate device that is dedicated to detecting the presence of a leak in the bag 161, 9100, 9300.
An alert provided to the user upon indication of CO2 and/or N2O may allow the surgical team to perform surgical intervention at the earliest possible opportunity to best manage the outcomes for the patient.
In some embodiments, and as illustrated in
The system 100 may use this information to alert the user of a leak as it occurs to allow the surgical team to perform surgical intervention.
With continued reference to
In some embodiments, a post-surgical procedure leak detection method is provided. For example, fluid pressure may be applied from a pump, cylinder, or other means to the space 9106, 9204, 9306, 9406 between the outer and inner bag layers or to the inside of the bag 161 with the bag 161, 9100, 9300, 9400 sealed around the air pressure device. A pressure detector may be used to measure the resulting air pressure, and/or decay characteristic. A visual indication to determine if a leak has occurred may also be provided.
The detection system may include a pressure detector, a pressure-control valve to limit the applied pressure and a vent mechanism. For embodiments that use the intermediate space, the lumen that provides access to the space can have a fitting that allows easy attachment of the leak detection system by the user. For embodiments that use the bag opening, an interface that fits into the bag opening and allows the user to constrict the opening onto the interface creating a seal. The bag may also have features that aide in creating a seal against the interface to improve the ability to perform the test.
The post-surgical leak detection method may allow the surgical team to perform a surgical intervention, if necessary, prior to completing the surgery.
In some embodiments, a leak detection method may include a fluid wash (such as sterile saline) between the bag layers after usage. The contents of the fluids may then be evaluated for biologic materials such as blood.
In some embodiments, a post-surgical leak detection method may include inflating a bag and placing under a liquid such as water to look for bubbles.
In some embodiments, after completion of the segmentation procedure, the specimen bag may be evaluated for leaks. For example, the operating room air supply may be used to fill the interior of the used specimen bag by hand grasping/sealing the bag opening around the air supply while inflating. Once the specimen bag is inflated, the opening may be twisted around itself to seal in the pressurized air. This inflated specimen bag may be (partially) submerged in a bath of water (i.e. a small cavity of the tray in which the specimen bag was shipped) to visually inspect for air bubbles escaping any breaches in the specimen bag. A surfactant may be added to the bag surface or water bath to modify the surface tension of the water and enhance the visible bubbling of the water.
Some embodiments of leak detection may include filling the intermediate space between bag layers or the interior of the specimen bag with a liquid, such as water or saline, and adding pressurized air to a predetermined pressure, thereby accelerating any leaks through any breech in the bag or bag layers.
In some embodiments, the bag surface may be visually inspected and/or may be dried with a towel or air, and migration of the liquid across the bag layer boundary may be visually inspected.
In some embodiments, a coloring agent or dye may be provided in the fluid introduced into the space, to enhance the ability to visually identify the migration across the bag or bag layer boundary.
In some embodiments, an outer bag layer 9102 may be made of a first translucent color and an inner bag layer 9104 may be made of a second color, and a space 9106 therebetween may be pressurized. A method of determining a leak may include visually determining a perceived change in color at one or more points of contact between the bag layers 9102, 9104. Visually determining may include using an endoscopic camera or viewing the outer layer 9104 during or after the surgical procedure.
For example, if the inner bag layer has a blue tint applied, and the outside layer has a yellow tint applied, the area of contact will result in a green tinted shape due to increase in optical coupling of the two colored layers.
In some embodiments, as the surgical procedure proceeds, a change is the size of the combined color area, particularly an increase, may indicate a change in the area of contact between the two layers. If a fixed volume of air is captured between the two layers in this intermediate space or if a slight pressure is applied prior to use, the increase of size of this color combined region can identify a leak of one of the bag layers.
Those skilled in the art will recognize that the procedure described above may also be suitable where a space 9106 between the layers is under vacuum. For example, if the layers 9102, 9104 pull away from each other, a leak is also indicated.
In some embodiments, a method of leak detection may include providing a moisture detection layer, and/or monitoring an electrical pattern indicative of conductive fluid or change in impedance due to fluids.
As illustrated in
In some embodiments, a first electrode 9608 and a second electrode 9610 may be positioned between the layers 9602, 9604 with or without the rest of the conductive mechanism 9606 or mesh.
The conductive mechanism 9606 may be in a pattern having a fixed spacing between two separate electrodes 9608, 9610. The two electrodes 9608, 9610 may be a single pair of electrodes that cover some or most of the internal surface of the bag layers or may be pairs placed at multiple locations that are electrically connected in parallel. The electrodes may be electrically coupled to a signal, preferably an AC waveform similar to the dual electrode monitoring interrogation waveform applied by electrosurgical generators to monitor return electrode contact quality. The signal may be generated from an electrical circuit located in the segmentation instrument 102, the monitoring unit or controller 108, or a separate remote location. The characteristics of the voltage measured across the electrodes and the current measured between the electrodes can provide the impedance across the electrodes. If the intermediate space is dry, the impedance will near an open circuit and be characteristic of the bag layer material conductance with the spacing of the two electrodes. If the inner layer leaks, then fluids or other material may enter the intermediate space. This fluid or foreign material will provide a change in the impedance due to the conductivity of blood, tissue or other body fluids. By measuring a reduction in the impedance between the two electrodes, a leak of fluids or other tissue that spans the electrode spacing can be detected.
Some embodiments of leak detection include measuring complex impedance, such that a short circuit created with bag folds or other means may be distinguished from the introduction of fluids or other bodily fluids or material by using the power factor angle. This could also be enhanced with adding a positive pressure to the intermediate space to reduce the chance of bag folds as well as designing the electrode shapes to align with areas of the bag that are expected to have folds so that a folded bag may cause an electrode to contact itself and not contact the opposing electrode.
Since bodily fluids of a significant amount are likely to fall to the bottom of the bag, an electrode or series of electrodes at bottom of bag can be used to detect when a fluid comes into contact with the electrodes or circuit. The electrodes may sense a resistance or capacitance. For example, the electrodes may have a liquid absorbing gel in the bottom of bag that changes capacitance if liquid is added.
Some embodiments of detecting a leak in the bag may include applying a volume of Helium (He) or inert gas into the contained intermediate space between the inner and outer layers of the bag. Using a gas spectroscopy detection technique, a helium detector, or an inert gas detector, placed within the bag, incorporated into the instrument such that the sensor is located within the introducer tube or located outside of the tube with a lumen connected to the introducer tube such that the sensor can sample the contents of the air flowing from inside the bag, such as in a smoke evacuation system. Any traces of helium or the inert gas indicate migration of the gas from the intermediate space to the inside of the bag which in turn indicates a leak has occurred.
In some embodiments, the detector is placed through an additional laparoscopic port such that any detection of helium or inert gas within the peritoneal cavity would indicate a lead between the intermediate space of the bag and the outer bag layer. This method may include suspending the insufflation while measuring for a leak.
Some methods of leak detection may include optically scanning for a leak during or after the surgical procedure.
Some embodiments of leak detection methods include using a camera to view the surface of the bag during the procedure. The camera may be inserted through a separate port and may be the endoscopic camera used during laparoscopy, or could be a separate camera intended to detect leaks. The image of the camera may be sent to a processing unit, such as the controller previously described herein or a different unit that can digitize the image in real time. The processing unit may also contain a datastore to store digitized images that can be used to compare real time imaging data. This comparison can be used to determine changes in the geometry of the bag as the procedure proceeds, such as the intermediate space thickness, which can provide an indication of a bag leak. The visual image can also look for a buildup of fluids on the surface or bottom of the bag, can look for drops forming or falling from the bag and can be used in conjunction with some of the other embodiments presented in this disclosure. For example, if a material is placed within the intermediate space that has a particular color, a filtering algorithm can be used by the processor to identify changes in amplitude of this color on the outer surface of the bag.
Some embodiments include comparing a bag after the procedure is complete to a measurement taken before placement of the bag into the patient or to manufacturers' specifications.
With reference now to
Some embodiments of leak detection may include providing or using a color changing moisture indicator between bag layers. For example, the specimen bag layers may be constructed of two welded layers of polyurethane, creating a sealed inner space between the two layers. A compromise or leak in either of these two layers may be indicated by a color changing chemical agent that would be applied to the inner space during bag construction. When the chemical indicator comes in contact with water based, human fluids a chemical reaction with the fluid would create a color change in the agent that would be observable either from the endoscopic camera in the body cavity or observable directly by the surgeon after bag removal. The agent may be sprayed on to either or both inner walls of the polyurethane during assembly of the bag. The agent may also be inserted in construction as a loose powder or as a film of liquid. Strips of colored paper or fiber may hold the color changing agent.
In some embodiments, a liquid agent may be inserted through a port after the bag is placed in the body. A color change between the two layers would only indicate that, at least, one of the two layers had been compromised since fluids could have passed from either side into the inner space. A follow up test may be useful to verify which of the layers had been perforated.
In some embodiments useful for leak detection, a spray-on coating on an internal surface of the outer bag may be provided and configured to bind to liquid. After the procedure, a visual inspection of the outer surface of the inner bag and/or the inner surface of the outer bag, using, for example, black light, may reveal if a leak has occurred.
To identify liquid escape from a breached inner bag layer, a coating on the outer-side of the inner specimen bag layer. This coating, when combined with bodily fluid, may be configured to bind with the infiltrating fluid, thereby creating a marker which may be visualized with the naked eye, and/or with the aid of secondary equipment, such as a black light. Inspection for a breach in the inner bag layer may be incorporated as a procedure after every specimen removal procedure by scanning each post-operative bag to look for the presence of this breach marker.
Some embodiments of leak detection methods and devices may include using a water color “no mess” markers pad that changes color in the presence of liquid. That is, to visually indicate a breach in the inner bag layer, a coating, similar to a dry watercolor pigment, may be applied to the void between the inner and outer bag during specimen bag manufacturing. If this void is breached & body fluids infiltrate this void space then the dry pigment will become saturated and provide a visual identification of a breached inner bag layer.
Some embodiments of leak detection methods and devices may include a finger print “dust” for leak detection. Similar to the watercolor pigment method and device described above, a powder may be inserted in the void space between the two layers of the specimen bag. Infiltration of body fluids into this space would turn the powder to a paste-link substance. This paste substance would make a visual identification of a breached inner bag layer possible.
In some embodiments, a color changing material may be used as one of the bag layers or in addition to and between the bag layers. If either of the bag layers is breached, the color changing material would change colors as a visual indication of the breach. For example, the material in between layers changes color when CO2 or N2O, which are typical insufflation gases, enter the space between the bag layers.
Some embodiments include using a color changing material at the bottom of bag only that absorbs any fluids that are within the layers. This color changing material may be configured to change color as a result of a protein, fluid, or other chemical signature of a biologic fluid.
Some embodiments of leak detection methods or devices include the use of a visual indicator, which may be with or without a camera between layers. To provide a visual indication of whether or not a breach occurred in the inner bag, the outer bag layer may be made of a white or similarly contrasting material such that the surgeon can look for blood on inside of outer white layer either during the instrument, use such as with a camera, or after use. Discoloration of the outer bag inner surface may indicate that a breach of the inner bag layer has occurred.
Some embodiments of leak detection devices 9700 and methods may include the use of one or more vacuum loss indicators, such as indicator tubes or geometries, as illustrated in
Embodiments of leak management are also described herein, to mitigate any adverse effects that may be caused by a leak. For example, in some embodiments, a chemotherapy agent specific to the procedure being performed may be placed in the interior space of the bag 161. The agent may be pre-placed into the bag, such as during manufacturing or pre-packaging of the bag, or the agent may be positioned in the bag in-situ.
In some embodiments, a chemotherapy agent in the space between the bag layers may be configured to kill cells on contact. The agent may be a specific agent that is chosen or configured to target the intended procedure.
In some embodiments, the agent is contained in a hydrogel or gel such that any cells that come into contact with the agent are likely to stick or adhere to the surface of the hydrogel or gel.
The chemotherapy agent may be selected based on the procedure and/or patient history. For example, if a uterus is being removed, a chemotherapy agent that would be indicated for a leiomysarcoma suitable for the patient may be used to best address any cancer cells that may migrate into the interior space of the bag or the space between bag layers.
For colon removal an agent that is indicated for an adenocarcinoma may be selected and placed in the bag.
In some embodiments, the surgeon and/or oncologist selects the chemotherapy agent and adds the agent to the space between the outer and inner layers just prior to use.
In some embodiments, the surgeon and/or oncologist may select from a range of pre-administered chemotherapy agents that are placed in the bag or between bag layers during manufacturing. The agent maybe applied in the form of a liquid with a safe quantity applied or may be applied as a film to either the outside layer of the inner bag or the inside layer of the outer bag.
In some embodiments of leak mitigation, an antiseptic or disinfectant solution of layer may be provided in a manner substantially similar to that described with respect to the chemotherapy agent previously described herein.
Some embodiments of leak mitigation include placing or using a layer of absorbent material in between the inner and outer bag layers such that if a leak occurs in the inner layer, the absorbent material will contain an amount of fluids or other material that breach the inner layer. This also provides some protection to resist both layers of the bag being damaged by instruments or other mechanical edges. The absorbent material may be a fabric, a foam, gel or other material that has highly absorbent properties to water.
Some embodiments of leak mitigation include providing or using an absorbent material that changes hardness or phases when in contact with a fluid. The material may be placed between the bag layers. It may be a dry substance that turns to a gel in some embodiments. In some embodiments, the substance may turn harder or softer, may be a powder or film that turns to a gel, or may change colors as a result of a chemically activated change. The material may change phases so as to be detected either visually, through physical palpation of the bag, etc.
Some embodiments of leak mitigation may include the use of or placement of a layer of viscous gel material between the inner and outer bag layers such that, if a leak occurs, the gel is configured to minimize the impact of a leak. The gel may, in some embodiments, close the leak; in some embodiments, the leak may increase the thickness of the bag such that a leak would have a lower probability of penetrating both the inner and outer bag layers and the gel layer. In some embodiments, the gel may be made of or include a biocompatible material. In some embodiments, the gel may include a hydrogel, such as that placed on return electrodes. In some embodiments, the gel includes a hydrophilic polymeric material, a biodegradable hydrophilic material, and/or an organic hydrophilic material. The gel may be added to the space between layers at manufacturing; or the gel may be added through a lumen in-situ.
The gel may be selected and configured to thermally insulate the outer layer from the inner layer, thereby reducing the likelihood of a breach of both layers.
Some embodiments of leak mitigation include the use of a multi-cell intermediate layer. A multi-cell layer between the outer bag layer and the inner bag layer may include a number of interior spaces that serve to reduce the volume of fluid that may potentially leak in the event the inner layer is compromised. For example, a number of walls coupling the inner layer and the outer layer may form a number of smaller fixed volumes of air, fluid, gel, or other leak mitigation or leak management means described herein within the space between the inner and outer layers of the bag.
In some embodiments, the smaller fixed volumes of air fluid, gel, or other leak mitigation or leak management means described herein may be provided by a third bag layer positioned between the inner layer and the outer layer. The third layer may include an inner wall, an outer wall, and a number of connecting walls coupling the inner wall and the outer wall, creating the fixed volumes therebetween.
In some embodiments, a multi-cell layer may include a plurality of sealed pockets of a fluid or a leak mitigation means. The multi-cell layer may be positioned between the inner layer and the outer layer. The multi-cell layer may limit travel of contaminated material and reduce the probability of contaminated material such as portions of a cancerous segmented tissue sample breaching the bag assembly. The multi-cell layer may be positioned exterior of both bag layers in some embodiments.
Some embodiments of leak mitigation may include the use of a material that solidifies when it comes in contact with bodily fluid. For example, an epoxy or any thermosetting material may be provided in the space between the outer and inner bag layers. The thermosetting material may be configured to solidify or harden in the event a breach of the inner bag layer allows material to reach the intermediate space. In some embodiments, the solidification may plug the breach. In some embodiments, the thermosetting material may be selected or configured to set within a period of time. The period of time may be five minutes or less in some embodiments. The period of time may be two minutes or less in some embodiments. The period of time may be one minute or less in some embodiments. The period of time may be thirty seconds or less in some embodiments. The period of time may be fifteen seconds or less in some embodiments.
Those skilled in the art will recognize that a faster setting of the thermosetting material may result in a weaker bond; however, this feature may be advantageous by enabling the surgeon to, after completing the segmentation procedure, break up the set materials and remove them through the incision site. Breaking up the set materials may be achieved without destroying the outer bag layer in some embodiments.
In some embodiments, a material that is reactive with carbon dioxide and/or nitrous oxide may be used or placed in the space between the outer and inner layers. The reactive material may be selected or configured to form a foam or gel, or to solidify, thereby mitigating the effects of any breach of the inner bag layer.
The preceding paragraphs discussed leak detection systems, methods and devices. Another aspect of the disclosure is directed to methods of leak testing which may be performed before, during, or after the use of a containment device for tissue specimens.
As discussed throughout this disclosure, for surgical procedures where tissue is excised and removed from the patient, containment of the specimen during removal is an essential requirement. Tissue fluids or fragments created by disruption of the vasculature, other fluid carrying ducts and the tissue structure can be released to spread to internal surfaces of the abdomen or thoracic cavity, which in turn can increase the chance of spreading cancer if the tissue specimen has a previously unknown cancer. To address this concern, a common surgical practice is to place the excised tissue specimen into a containment device to capture fluids or tissue fragments during the tissue removal process. These containment devices often are made of thin polymer films to create a sealed containment bag that is flexible for manipulation during the removal process. As the film or containment barrier is often the only mitigation to ensure containment, detecting a leak during or immediately after surgery is significant benefit.
Currently there are several means to detect leaks in a containment barrier, including those discussed in the present disclosure above; however most are not practical in a clinical setting. The most common method used in surgery is for the surgeon to visually inspect the bag for fluids on the exterior of the removed containment barrier. This method provides a gross indication of leaking but does not differentiate fluids that were deposited on the external surface of the bag during loading or exteriorization from fluids that migrated through the containment barrier. Another method is to use a bacterial escape method in which an aberrant bacteria broth is placed either inside or outside of a sealed containment barrier and after incubation, the opposing surface of the barrier is checked for growth of the bacteria.
This method has practical limitations for larger containment bags. A first limitation is that using a “local” leak detection method, such as bacterial swabbing for bacteria on the outer surface, can be problematic in detecting a pinhole leak over the entire bag surface. A second limitation is that bacterial growth methods require several days to complete and will always have contamination risks that exclude samples or may yield false positives.
Other methods such as dye testing and bubble testing can identify a larger leak, however these require extended time for small leaks. Additionally, dye testing using fluid volumes for bags which may contain large volumes of fluid, such as standard tissue specimen bags, creates a water column whereby pressure near the bottom of the bag may in the range of 0.25 or more psi (lbs./square-inch) and pressure near the top across the barrier is nearly zero.
Methods of leak detection such as pressure decay testing or detection of gases leaking out of the containment barrier with “sniffers” require specialized equipment that is not practical in an operating room environment; these methods are also limited by the mechanical ‘compliance’ of a polymer bag, which makes detection of very small leaks problematic in practice where the polymer compliance results in pressure decay on the order of the decay observed for a small hole.
The present disclosure provides methods to test containment of a barrier. A containment barrier in the present disclosure may refer to a bag having one or more layers; for example, it may include a single-layer or dual-layer containment bag. In such embodiments, the method may test a containment barrier comprising a sheet or film. The method may comprise placing the barrier into an ionized fluid, or an electrically conductive fluid, so that the fluid is in contact with a first surface and a second surface of the containment barrier.
In embodiments, one or more volumes of fluid may be used to fill areas defined by the first surface and/or the second surface. For example, a volume of fluid may be used to fill an inside of a containment bag, and another volume of fluid may be used to fill an area outside the containment bag but within an outer containment vessel. In another embodiment, the containment barrier may be a film or sheet situated within an outer container or vessel, and a first volume of fluid may be placed on one side of the barrier and a second volume of fluid on a second side of the barrier. The one or more volumes of fluid may be the same type or may be different types. In embodiments, a containment barrier may be placed in a container first and then one or more volumes of fluid placed in or around it, or a fluid may be placed in a containment vessel first, then a containment barrier placed within the fluid. In embodiments using a containment bag, a fluid may be placed in an outer vessel, then the containment bag may be placed in the fluid, creating a first volume of fluid outside the containment bag. Then a second volume of fluid may be placed in the inside of the containment bag.
The method may comprise placing one electrode in a first volume of fluid on the first side of the containment barrier within the fluid, and a placing a second electrode (e.g., second electrode 101244 of
The method may further comprise pressurizing a volume of air above one or more volumes of fluid. A leak testing device of the present disclosure may be used to perform one or more aspects of the method. An exemplary leak testing device is shown in
The fixture cap 101340 may also comprise a valve 101344 which may be used for filling the bag with fluid and providing a shape over which the bag opening may be sealed. The fixture cap 101340 may also comprise an air pump hole 101346. The air pump hole 101346 may be used to allow an air pump 101360 to pressurize a volume of air above a volume of liquid. One purpose of pressurizing a volume of air in the method of the present disclosure is to push fluid through even very small holes in the containment barrier. Even slight movement of fluid across the barrier can be detected through the changes in electrical conductivity and can help locate where a very small hole is. Each of the holes in in the fixture cap 101340 may be sealed such that air may not escape through them when the volume of air is pressurized.
In embodiments of the present disclosure, the height (or “level”) of the fluid on both sides of the containment barrier (e.g., inside and outside the containment bag) may be the same. Using fluid levels on both sides of the bag allows for uniform pressure across the bag surface, and thus applying air pressure to the interior of the bag results in this same pressure being uniformly applied over the whole surface. In other words, the fluid columns on both sides of the bag ‘cancel out’ any fluid column pressures, and any pressure applied to the interior can be uniform over the tested surface area.
One embodiment of this method may comprise using saline as the ionized fluid. The containment bag or barrier may be held in place within a larger non-conductive vessel. In embodiments, the vessel may be non-conductive, and made of plastic, ceramic, glass, or the like. In other embodiments, the outer vessel may be conductive and function as a second (or “outer” electrode). In such embodiments, a conductive vessel may comprise stainless steel, brass, or other metals. It may also comprise inert plated materials, such as gold or platinum-plated materials. Such inert plated materials may use high quality electroplating in order to minimize unwanted effects of pores or pits, such as unwanted voltage reaction “noise.”
In embodiments using a containment bag, both the interior of the bag and the space between the exterior of the bag and the vessel wall may be filled with saline to the same height below the bag opening. An electrode (e.g., electrode 101350 of
The electrical resistance may be calculated to have a direct correlation to the size of any holes in the containment barrier. The multimeter may then apply a small voltage with a driving current between the electrodes to measure the resistance between the two electrodes. The saline ions may conduct this current through the saline solution with the barrier placed in between the current conduction path. As a result, any leak in the bag large enough to allow saline ions to conduct current through the leak will result in a detectable resistance. Also, as the entire surface of the bag below the saline fill level is in intimate contact with the saline, any leak present in the barrier will be detected, including all bag seams and film surface.
Sensitivity of the resistance measurements may be modified with changes in the concentration of the saline solution. In embodiments, the electrodes used in this method may be a) non-corrosive, like brass or stainless steel; and b) the same for both the anode and cathode, to prevent any applied electrochemical potential between them. It is likewise possible to use dissimilar metallic electrodes with different electrical potentials in saline, to impose a potential between the two electrodes (an additional voltage) to make the test more or less sensitive. In embodiments utilizing dissimilar electrode materials with substantially inert metals, any imposed voltage may be effectively “offset” by utilizing reverse polarity switching. However, such an embodiment may be less sensitive than an embodiment using similar electrodes, because the different electrodes may result in the measurements having more noise signals.
In embodiments where one of the electrodes is a conductive container; generally, making both electrodes (or electrode/container) of the same material will avoid electrolytic (battery) effects; however, using the reverse-polarity switching method described later in this disclosure, even battery effects of dissimilar electrode could be overcome, provided the electrode materials do not irreversibly corrode and mainly reversible passivation reactions occur.
When applying a voltage (such as with the “ohms” setting on a typical multimeter) it is likewise important to note that the applied voltage does vary from one meter to another, and among different ranges on any meter. It is advantageous if this applied voltage is known, or controlled, so that in the testing range used to identify conductivity across a bag hole or defect, the applied voltage is constant for calibrating the test method. Variations in this applied voltage to the electrodes may alter the apparent resistance at the electrode/fluid interface. A four-pole method, which will be described in detail presently, is an alternative which may minimize this effect, but the testing can be performed using just a two-pole method so long as testing can be performed using the same applied voltage or the same range-setting within the range of interest for identifying defects.
Four-pole method. As noted, a four-pole resistance method may also be used for the electrical resistance test. In this disclosure, the terms “pole” and “electrode” may be used somewhat interchangeably. Four-pole methods may be used for resistance measurements for various types of equipment. In such a method, two pairs of electrodes are used: one is the ‘active’ pair, which provides the active voltage for the measurement, and the second pair is the ‘passive’ pair, which may be used to only passively measure the voltage. The passive electrode pair may be situated in between the outer active pair. As a result, a configuration such as one in which the outer container acts as an active electrode may be advantageous.
Other configurations may be used depending on the configuration of the containment barrier (e.g., a containment bag or a flat containment sheet). For a containment bag test, an array of passive electrodes may be used, situated around a central active return electrode with the active electrode at the center of the bag. In a flat-sheet configuration, the passive electrodes may simply be placed closer to the sheet than the active electrodes.
The passive electrodes used in this four-pole method simply measure the voltage drop between them and have no current flow between the two. The active electrodes apply a voltage and the current is monitored; the combination of the current value from the active electrodes and the voltage measured by the passive electrodes determines the resistance across a hole or defect. When there is no defect, then the current for a given voltage will be very small, and thus the resistance will be very large, or nearly infinite.
The four-pole method allows the contact resistance at the active electrodes to be ignored, since only the current is being measured through those electrodes; and since there is no current flow on the passive electrodes, they will measure the actual voltage across the solution. This method may substantially reduce the passivation effects seen on active electrodes, but the switching or reverse-polarity method may still be applied to maximize accuracy.
In other embodiments, multiple passive electrodes or multiple active electrodes (i.e., a total of greater than four), may be used as well. In such embodiments the method may include “triangulating” the path length differences between them to estimate the location of a defect or hole. With adequate system sensitivity, differences in the path length between electrodes for the current pathway may establish the proximity of a defect to the closest electrode. This embodiment could both detect a hole or defect and provide information as to its approximate location, and could be combined with adjusting fluid levels (as in other embodiments in which the adjusting fluid levels are used to estimate the height of a defect in a bag configuration).
Turning now to the types of fluids that may be used embodiments of the disclosure, in one embodiment, a 5% NaCl solution may be chosen. Using this 5% saline solution, the relation of hole sizes versus resistance follows an inverse power-law relation between a very low impedance with no barrier present, or much less than 1 k-ohm, to an open circuit if no leaks are present. For leaks that are present in the barrier, the hole detection relationship will be in the range of Hole size (μm)=1936/Resistance (kΩ). Those skilled in the art will know that the value of this relationship can change with many factors, including the ion concentration, in this case the saline concentration, the test setup, the size of the barrier and distance between electrodes, the barrier material, the hole shape, the flexibility of the material, as well as other factors including but not limited to the applied voltage amplitude, the measurement type (two-pole or four-pole resistance measurement method), the electrode material, shape and size.
Any ionized solution or gas may be used as a conductive media and can be selected based on the leak size desired for detection by selecting the fluid surface tension with the barrier material or the molecule size of a gas. Note that ionized gas (plasma) is used in a similar method for testing latex condoms, where the condoms are placed over metallic mandrels/forms, and a high voltage potential is applied between the mandrel and another electrode. This method uses much higher voltages, requires a bag or condom that can be fully stretched over the mandrel piece and the entire surface is in uniform contact with the mandrel. With bags that are not stretchable, or that have irregular seams, this method would not be as practical, and the use of an ionized fluid or ionized gas on both sides would be preferred. An ionized gas/plasma method would require very high voltages, which are avoided by using the ionized fluid method.
An important area to ensure is that the ionized material must not be allowed to pass around the barrier for any containment barriers that are not completely sealed. This “leakage” can result in a false positive reading. For example, embodiments of tests may use surfactants (such as dish soap) to reduce surface tension. Any residue or films from leaks or drips can create a conductive pathway. In general, the lower the ionic solution surface tension used (which allows detection of smaller holes the fluid can pass through), the greater the risk of accidental leak pathways. This can be addressed by proper scaling of any openings in the containment barrier or by using fluids with higher vapor densities than air, such as saline. The top of the containment barrier should be completely “sealed” from any fluid transfer, but need not be air-tight. Air leaks may be permissible, so long as soap bubbles aren't being generated and passing through them.
The containment barrier leak test of the present disclosure can be performed at ambient pressure or by sealing the opening so it can have a positive pressure applied within the internal portion of the bag, or the bag can be held at a fixed volume and a positive pressure applied to the exterior of the bag to challenge the containment beyond static conditions. As most containment barriers are made of flexible materials, the addition of this pressure can extend any openings in the back increasing the chance of detection. In addition, adding a pressure differential can help overcome any capillary action, or a hydrophobic fluid action, across very small holes to provide more consistent and repeatable resistance readings. In other words, in hydrophobic polymer bags (which are embodiments of containment barriers), fluid will tend to not go through very small holes unless 1) the surface tension of the fluid is low enough and/or 2) the pressure gradient across the hole is high enough to overcome capillary pressure. Therefore, using very low surface tension fluids, the method of the present disclosure can be used to detect smaller holes at lower pressures (such as ambient pressure). However, it is also advantageous to check for holes at a maximum expected pressure. For example, if a containment bag is filled with tissue during surgery, there would be quite a bit of pressure on various parts of the bag. Therefore, the test methods of the present disclosure are designed to test for holes in situations with high pressure and low surface tension liquids. Also, for the case of the saline embodiment previously described, by filling the external portion of the bag and the interior of the bag to the same saline level, the bag is uniformly pressured throughout its surface to the applied test pressure, as opposed to a drip/dye method-type test where the pressure varies from the top to the bottom of the containment barrier.
Advantages of using the ionized fluid conductivity method of the present disclosure for containment barrier leak testing are that it is adequately sensitive to detecting microleaks smaller than cancer cells (≤3 μm in diameter), it ensures that the entire containment surface is tested, and it provides virtually instantaneous results
Electrode Types: An aspect of the leak test method of the present disclosure relates to the choice of electrodes used to implement the method. The choice of electrodes may be important because the electrode/solution interface produces a background resistance that can limit the sensitivity of the test method. In many embodiments, the resistance of the electrode/solution interface is large compared to the resistance seen in the solution. This high electrode interface resistance means the distance between the electrodes becomes less important when making measurements to correlate with an apparent hole size or defect size. Relative invariance in the resistance between the electrodes versus the electrode spacing means that the location of the hole in the bag, relative to the positions of the electrodes, becomes irrelevant: nearly the same electrical resistance signal will be seen for a given hole size, regardless of the actual position of the hole, or the cumulative distance from the hole to each electrode.
Electrical distance invariance is determined by direct measurement of a type (material) and shape of the electrodes chosen, and the conductivity of the ionic/conductive solution. The variation in resistances for electrode spacing (e.g. 5 cm to 40 cm) is measured to be small relative to the nominal resistances measured for the full spacing range. Generally, a 10× ratio (of resistance between the electrodes in solution at their actual distance compared to the expected resistance of the pathway through the solution at the longest possible pathway) or greater may be used, but ratios of resistance as small as 2×-3× may provide acceptable testing accuracy and acceptable spacing invariance and therefore may be used in embodiments.
Non-corrosive materials for electrodes are advantageous because they prevent electrode degradation during testing However, even non-corroding electrode materials can create problems in measurement due to reversible passivation reactions that alter the electrode/solution resistances over time as a bias-voltage (constant current signal) is applied. This passivation reaction can be thought of as a “battery effect”, which can literally ‘charge up’ one electrode with continually applied voltage over time, affecting measurement accuracy significantly. For example, a Type 304 stainless steel electrode pair can have the measured resistance change by up to nearly 1 MΩ over a 5-minute small voltage application.
A marine grade brass (485 Brass) electrode may be used in embodiments of the disclosure because it-is both corrosion resistant and produces a much smaller passivation ‘battery effect’ with applied voltages during measurement. However, the effect does persist and can impact accuracy if the electrodes are passivated in the same electrical direction (polarity) over time.
A method (the “reverse polarity method”) to further offset this effect is to perform resistance measurements in both directions/polarities, by rapidly reversing the polarity of the applied voltage using a manual switchbox, or an electrical relay setup. In embodiments, a 3-pole switch may be used to keep the applied electrical current or voltage in the “off” position (Position 1). Then the switch may be moved to Position 2, and a measurement may be made after a set period when the measurement settles (e.g. 1 s to 5 s); then the switch is quickly flipped to Position 3, which applies the current or voltage in the opposite polarity to Position 2, and a resistance measurement is made after the same settling time. When the setting times of the two polarities are roughly equal, then the average of the two resistance measurements (at each polarity) will cancel out the cumulative passivation effects, and provide more repeatable and reliable readings.
Alternatively, identifying a non-reactive electrode with adequate conductivity (e.g. graphite electrode) or a reference liquid electrode (saturated calomel electrode or silver chloride electrode) which does not exhibit any passivation/battery effect could also be used. These types of electrodes, used in standard electrochemical measurements, are much more complex to work with and maintain, however. As the reverse-polarization measurement technique is quite effective in offsetting/eliminating the errors, and the use of metallic electrodes greatly simplifies the testing setup, a material like Brass 485 and the reverse-polarization measurement method is often more advantageous.
Passivation effects may also be less pronounced with larger surface area electrodes, as the applied current concentrations at the electrode/solution interface are smaller. Thus, while larger electrodes are may be beneficial for minimizing or controlling passivation reactions, they may also reduce the electrode/solution interface resistance closer to the resistance of the solution pathway, and reducing the ratio of electrode resistance to solution resistance.
Another embodiment of the method may comprise using larger electrodes conforming somewhat to the shape of the bags being tested, so that the distance between the electrodes across the bag is nearly uniform at all places. In this embodiment, the ratio of the electrode interface resistance to the solution resistance becomes unimportant. One embodiment of this type of electrode setup may comprise a conductive cylinder (or mesh in the shape of a cylinder) fitting inside the bag, with a second cylinder outside the bag. The outer cylinder may be separate from the solution containment reservoir or may also function as the solution containment.
Another embodiment may comprise using a resistance measurement that provides an alternating voltage and current waveform, such as a sine wave, to measure the resistance. This may offset the polarization effects common with a DC measurement approach. In this embodiment, measurement equipment that can deliver an AC waveform such as an LCR meter may be implemented. As the method is concerned with the resistance measurement related to the hole size, the frequency of the measurement waveform is not critical; however the bag film may act as a capacitance between the interior and exterior electrically conductive solutions and may therefore create a capacitance that should be considered in calibrating the response curve. Those skilled in the art will recognize that other waveforms may be used to detect the resistance between the two electrodes and that means other than standard instrumentation may be used to perform this measurement, such as a resistance measurement circuit designed specifically for this application.
AC and DC Measurement: As stated above, either AC or DC signal measurement may be used in the method of the present disclosure. Capacitive reactance may also be implemented. The embodiments described have primarily focused on a DC measurement system, where one electrode is the positive (“+”) and the other is the return or negative (“−”) (or, for the four-pole setup, one active electrode is “+” and the other is “−”. These embodiments measure a simple DC resistance across the solution and the defect or bag. An advantage of the DC setup is that it can be performed with a single precision multimeter instrument; however, the electrode-solution interface passivation or corrosion effects are a consequence, with the reverse polarity switching being a useful method to cancel out those effects.
A second method to minimize the passivation effects is to use an AC signal on the active electrodes, so the passivation effects cannot build up on the electrodes during measurements. An AC signal of sufficiently low frequency (perhaps <10 Hz) will also minimize capacitance effects that will occur across a test membrane or bag. At high enough frequencies, the bag layer will act like a capacitor, with charges building up along the surface and capacitively conducting current across the layer. It is contemplated that using the lower end of the frequency range will minimize this effect, and that at higher frequencies (such as 1 kHz and up), there should be adequate capacitance across a bag or film for current flow between the electrodes.
Additionally, by also monitoring the phase angle of the current and voltage, a defect or hole may show a different phase angle for the AC signal than capacitance across the bag. Thus, for higher frequencies where the capacitance allows for conductivity across the bag or film layer, the phase angle between the voltage and current may change as a defect is observed and that ratio between direct AC electrical conduction and capacitive conduction will also change with the hole size. If there is no hole, a reading would show a 90° shift in the phase angle (full capacitive effects), and as the hole gets larger, and a greater fraction of the current is traversing the hole, that phase angle shifts toward ‘0’. For ‘no capacitance’, at the low frequencies, there would not be measurable phase angle, as very little current is being passed capacitively.
Another possible embodiment comprises varying the applied frequency to “tune” the capacitive reactance of the bag of film layer being tested, until it matches the resistance of the hole. When the capacitive reactance is equal to the resistance of the hole, then the phase angle becomes 45°. This is another method of indirectly measuring the resistance of a hole, but using the reactive phase angle to tune the frequency so the native bag or layer produces the same resistance (or actually reactance) as the hole. This embodiment does not comprise actually measuring the resistance of the bag, but rather a phase angle at a frequency, and is a way of using conductive fluids without requiring a formal “resistance measurement.”
This method of measuring the phase angle works as described in further detail herein. A bag with an AC applied voltage signal may induce a capacitance across a thin bag film (or across a flat containment barrier) between the two volumes of fluid. This capacitance varies primarily with just the surface area of the bag, and the polymer material and thickness, but should be a “fixed number” for any specific configuration. When there is a change the frequency of the AC signal, the capacitive reactance (or complex resistance) of the bag or film will vary with that applied frequency. The capacitive reactance varies inversely with the applied frequency, so that reactance gets smaller the higher the frequency goes (Xc=1/(2*pi*f*C, where C is the actual capacitance).
If the capacitive reactance can be varied with the frequency to reactance (or resistance) values that match that of a hole in the bag, then this reactance is ‘in parallel’ with the hole, or it looks like a capacitor in a parallel resistance circuit with the resistance of the hole. When the capacitive reactance and resistance in the circuit are equal (the combined resistances of the electrodes, solution and hole), then the phase angle between the applied voltage and resulting current becomes 45°.
In a pure resistance circuit, the phase angle between V and I is 0°. In a pure capacitor, the phase angle is −90° between V and I. By changing the capacitive reactance by virtue of adjusting the applied frequency, the phase angle for a bag with a hole will reach about −45° when the capacitive reactance and the resistances are equal (and if the resistance of the hole is much larger than the resistances of the electrode interface and solution, then this mainly occurs when the capacitive reactance equals the hole resistance). Thus, by sweeping frequencies until reaching a −45° phase angle, one can estimate the size of the hole without actually measuring the resistance, but simply measuring for which frequency this phase angle shift reaches −45°. At that frequency, one can then simply compute the resistance from the capacitive reactance formula (knowing the capacitance of the bag).
By using this AC measurement technique, the complex reactance reading may be determined by a resistance and capacitance for the measured signal waveform. As the capacitance will be determined by the dimensions, thickness, and material properties of the bag, it will be similar for a particular bag type. This capacitance can be used as a constant and mathematically used to calculate the resistance from the reactance reading to determine the detected hole size.
Also, a single or multiple frequencies can be used to measure and develop a parallel RC model which can be used as described above to calculate the resistance from the reactance of the RC model, in a similar manner as a LCR meter, to determine the detected hole size.
This embodiment may be used as an alternative to directly measuring resistance by instead calculating resistance capacitive reactance and phase. Different hole sizes (which have a different resistance ranging in testing from many MΩ to just a few kΩ) results in a −45° phase angle across a fairly wide range of frequencies.
The formula used in this method is the phase angle equals the arctangent of the resistance/reactance ratio, theta=atan (−Xc/R).
The sign of the phase angle here simply indicates the voltage lags the current per electrical engineering conventions; atan (−infinity)=−90°, for pure capacitance.
The phase angle may be arbitrarily selected and the tangent of that angle defines what resistance/reactance ratio is being measured. The greatest sensitivity is likely where they are equal, as the method would be most accurate when the two resistances/reactances are ‘balanced’ versus biasing the measurement near 0° or −90°. In other words, measurements would be least accurate at the extremes.
Solution Types: As noted, the embodiment of using a solution to fill the bag to the same height as an outer solution outside the bag provides the ability to maintain a uniform pressure across the bag at every position, based upon pressurizing an air chamber above the inner solution to a fixed/static pressure. This is a substantial improvement over typical drip test methods, where the fluid column applies the highest pressures at the bottom of the bag, and almost no applied pressure exists at the top of the fluid column.
Additionally, the surface tension of the fluid can impact the sensitivity of the test method for very small hole sizes. For high-surface tension fluids (>70-75 dyne/cm), the capillary action of the fluid against a hydrophobic polymer bag may prevent electrical measurements for small hole sizes. Biologic fluid surface tensions can range to as low as 42 dyne/cm, and the addition of higher saline concentrations may increase the fluid surface tension and further limit test sensitivity.
An aspect of the present disclosure is that by reducing the fluid surface tension to 42 dyne/cm or less, even very small holes can be detected, down to 1 μm in size. This reduction in fluid surface tension may be accomplished by using various soluble additives to adjust and lower the fluid surface tension. Polysorbates may be used in embodiments, as they can be added to levels above the saturation limit with little impact on the solution conductivity. Polysorbate 80 (Tween 80) can lower the surface tension to around 40 dyne/cm; Polysorbate 20 (Tween 20) can further lower the surface tension to around 30 dyne/cm. Any surfactant which has a minimal impact on the solution conductivity and lowers the surface tension could be utilized.
A complication with saturated surfactant solutions is that, over time, precipitates can form in the solutions which can occlude very small holes during measurement or system calibration. Filtering these precipitates out prior to testing prevents them from affecting measurement accuracy. Ideally, surfactants that do not produce any precipitates over time would be used in embodiments, provided they can produce reliable and stable surface tension levels that do not change significantly over time.
Ideally, a collection bag made from a polymer material which has no electrical conductivity is advantageous for use in the electrical leak testing method of the present disclosure. This means that 100% of the resistance signal measured is due to an actual leak or defect in the bag.
However, some materials do exhibit electrical conductivity that is either stable with fluid exposure or can change over time with fluid exposure. These bag materials create complicating factors with an electrical conductivity leak test method. In practice, these factors can be accounted for with some degradation in system sensitivity and accuracy.
When a bag layer has a native resistance or conductivity that is similar to, or even lower than, the resistance value of a target hole size to detect, the resistances will act as though they are combined in parallel. When this occurs, the parallel resistance of the hole, even though it may be higher than the bag, reduces the overall resistance by a predictable amount. The combined resistances may still enable hole detection, but the minimum detectable size becomes limited by a combination of the nominal range of native bag resistance (e.g. the +20 error) and the error estimates for the targeted hole size limit. To prevent “false positives” in detection, the lower-limit of the native bag resistance will define the limitations on the smallest detectable hole.
Thus, using the parallel resistances model, hole detection—with some limitations—is still possible with bags made from conductive polymers. In this case, identifying ways to lower the resistance of the solution (e.g. higher saline concentrations) and the electrode-solution interface) can improve the detectability of smaller holes by bringing those resistance values closer to or lower than the native conductivity/resistance of the bag material. It is also important to note that the exposed surface area of the conductive bag material is important to control when measuring the resistances in bags produced from these materials, as variations in the exposed surface area will change the measured electrical resistance proportionally.
In embodiments of the disclosure, the leak test may be performed on a single-layer containment bag or a dual-layer containment bag. The dual-layer containment bag may have an inner and outer layer. In such tests, while simultaneously testing the dual layers of the bag when pressurized, there exist two situations where it is possible for a conductive path to be created that result in an incorrect reading. Turning now to
This inadequate seal may be mitigated by attaching a plastic sheet between the top of the bag and leak test device along the entire perimeter of the leak test device.
During repeated testing, fluid can drip onto the leak test device as the bag is inserted and removed from it. This residual fluid can create a conductive path between the inner and outer electrodes, which can influence test results. A possible modification to the leak test device is to substitute the outer electrode rod immersed reservoir of free-standing fluid with an alternative configuration to reduce the amount of fluid unintentionally spread onto the test fixture. These embodiments may include replacing the free-standing fluid with a material saturated with fluid that is able to generate a layer of conductive fluid that contacts the bag surface when the bag is in contact with the material. Other embodiments include substituting the fluid with a more viscous conductive gel or other conductive media that can be compliant with the bag as it is filled with a conductive fluid or pressurized.
Another modification comprises utilizing a saturated material. The saturated material approach may use an absorptive material to absorb a conductive fluid, such as saline solution, and contain the fluid until a force is applied as the bag is pressurized by filling with the conductive fluid or with additional pressure. When a force is applied, a sufficient layer of fluid is released to create a conductive path through any defects or holes in the bag. It is acceptable for the material to maintain a fluid layer even when no force is applied, as long as the layer is not excessively large. Materials that may be saturated with conductive fluid in embodiments of the disclosure include conductive foam, melamine sponges, electrode sponges, or Porex. Ideally, the material is able to maintain a relatively uniform fluid distribution throughout its structure to ensure consistency in the measured electrical resistance. However, a mechanism to periodically or continuously replenish the fluid can resolve this.
Another method to reduce the overall saline comprises creating a fixture with electrode sheets that fit closely to the bag dimensions and contact all sides of the bag. The space between the electrode sheets is filled with a conductive fluid or gel to ensure adequate contact throughout the bag. The fluid can be periodically replaced manually or through a pump mechanism.
O-ring Seal: As was previously discussed in the disclosure, the integrity of the seal between the bag opening and the leak test device is important if pressurization of the bag is used during leak testing. Leaks in this seal can compromise the accuracy resistance readings. A method to seal the bag to the fixture is to use a soft rubber ring and a hose clamp, an embodiment of which is shown in
The purpose of an electrosurgical generator is to deliver therapeutic RF energy for many different applications. The original use was for cutting and coagulation. Later, waveforms and handheld devices were created to apply desiccation, vessel sealing and ablation. Other novel approaches have been created including tissue specimen segmentation such as described in U.S. Pat. Nos. 9,522,034 and 9,649,147. In all of these applications except for coagulation, a waveform, typically a sinusoid, is delivered to affect the tissue in a controlled manner.
With direct contact applications, such as desiccation, bipolar cutting and coagulation, vessel sealing and ablation, the current flows through the tissue with little to no arcing between the end effector and tissue. With non-contact applications, such as monopolar cutting, an arc between the end effector and the tissue, or simply “the load,” is used to initiate the cut and lower level arcing within the plasma created by that initiation sustains the arc at relatively lower separation for the duration of a cut. Excessive arcs can occur as the separation between the end effector and tissue become greater, or simply “a load transient.”
With many of the more recent applications of RF energy, it is desired to control the RF energy to a lower level or with less collateral thermal damage, such as in tissue specimen segmentation. For segmentation, separation of the wire from the tissue is controlled with a coating on the wire resulting in a very low-level arc for initiation which is similar to the arcs created while sustaining the segmentation. This results in a lower arc event segmentation that maintains lower temperatures during the cut and much less desiccation of the tissue planes.
For tissue segmentation, as well as all contact applications, if a more significant arc event occurs, it can cause damage to the surrounding tissue or the end effector if not designed for this. If the significant arc event continues for a sustained period of time, it also results in the tissue temperature to increase significantly and the concern for collateral tissue damage is greatly increased.
Many previous electrosurgical generators have included circuits or software to detect an arcing event and disable or reduce RF energy if an undesired arc is detected. These typically detect transient or step changes in current or voltage or may rely on a filtered output of these parameters for detection. These types of embodiments have mixed results due to many reasons. The sensitivity tradeoff of differentiating an arc event that is intended verses an arc event that is aggressive and undesired. Also, many generators still use time averaged RMS sensors that cannot detect transient events accurately requiring separate circuitry to perform transient detection which typically are not as accurate or are more sensitive than the time averaged response used for the control loop. Finally, the combination of the generator output topology and the control loop (e.g. resonant LLC or LCC or quasi resonant, and average power or voltage or current control) has an impact on the level of intensity contained within transient arc events. Generators with output stages designed specifically to store less energy in the output during any given RF cycle and any given load, when combined with fast responding control loops designed specifically to handle transient events, can theoretically control arc events well. Where as generators with relatively large energy storage in the output that cover a large number of cycles of RF combined with relatively slow responding, time averaged, control loops, even if highly accurate over that time, will tend to deliver larger arc events during load transients and be slower to respond if the generator can detect such an event at all.
A different method to detect an arc is to use any combination of a minimal number of measured cycles of power factor or crest factor as an indication of an undesired transient arc event. The power factor is the ratio of the real power delivered to the tissue and the apparent power. The power factor is an indication of the quality of the RF effect whether it is sustained cutting, vessel sealing, desiccation or ablation. If the RF delivery is controlled with minimal undesired arcing, the power factor will be very near 1.0 as any sustained arc combined with the tissue impedance is mostly resistive and the delivered energy will be providing work to vaporize and separate tissue cells and structures for cutting, heat and seal vessels or tissue bundles for vessel sealing, or heat localized tissue for RF ablation. If the end effector is not in contact with the tissue and no arc is present, the power factor will be near 0.0 as the load impedance is all capacitive and the delivered energy is not performing work and any current is capacitive leakage current. As the monopolar cutting device approaches the tissue, or if a contact application device has a breakdown that creates an arc, the power factor will have a momentary value between 0.0 and 1.0 depending on the effective impedance. The impedance model may be characterized as a classic spark gap model where there the series capacitance across the gap dominates over the tissue real resistance before arc-over and therefore appears to be more capacitive and higher relative magnitude in impedance than the current that travels through the resistive tissue appears. In this manner, the power factor can be used as an indication for the “quality” of the cut or contact application energy delivery.
The crest factor is the ratio of the peak voltage to the effective or RMS voltage of an electrosurgical output waveform. These are typically fixed for generator outputs into rated resistive loads and are created by the RF output stage design and the waveform delivered through the RF stage. For most electrosurgical generators, a continuous sinusoidal crest factor will be near 1.4 depending on the level of harmonics or distortion of the generator design. When an arc event occurs, the RF waveform delivered to the tissue is disrupted by the transient high current which shows up in the crest factor as a distortion. A small arc event will have minimal effect on this distortion as the RF output stage will have the ability to deliver the current demand from the arc event. As the arc event becomes more extreme, the RF output stage will have a reduced ability to maintain the ideal sinusoidal output waveform. This will cause a distortion in the fundamental output characteristics that will increase the effective crest factor delivered during the arc event. In this manner, the crest factor can be used as an indication of an arc event with the relative increase indicating the level of the arc. The current crest factor, or ratio of the peak current to the effective or RMS current may also be used and may have some benefit depending on the operative parameters of the system. For generator outputs designed primarily as voltage fed inverters with relatively low output impedance, going through a transient arc event, the comparative crest factors of the current and voltage will tend to diverge with the crest factor of the current tending to be higher than that of the voltage through the event.
Any combination of the power factor and crest factor can be used as a method to detect an arc event and differentiate an acceptable arc from an extreme or undesirable arc event. In addition, other electrical factors can be used such a voltage, current or impedance range in which the arc detect algorithm would be enabled. This could reduce false positive indications. In addition, a time filter or time variant characteristics can be applied to the detection such that an excessive arc event that sustains for a period of time or has a time varying characteristic can be used as a differentiation of a desired or an undesired event.
As described above in the arc detect method above, the RF output stage design can impact the crest factor and to a lesser degree the power factor values that will be measured during an arc event. This is due to the fundamental crest factor designed for the particular generator, the dynamic load characteristics of the output for a transient load event and the ability of the generator to deliver energy to a reactive load. This is typically not an issue for a generator in and of itself, but can be an issue if combined with a separate external controller with the arc detection sensors. As a result, it may be desirable to have different values for the arc detection algorithm for different generators used as an energy source. This can be addressed in several ways including limiting use to a previously characterized generator. Another method would be characterizing multiple generator systems and have a selection process to align the arc detection algorithm settings with the generator in use. This can be a user-initiated selection or a communication between the generator and controller. Another method would be to have an adaptive means to detect the generator. This can be accomplished by applying a step function RF input to a test load integrated into the controller to measure the electrical characteristics of the RF waveform. Voltage rise times, current values, power values damping characteristics may be used to discern the type of generator or narrow the range of values for the arc detect algorithm. Another method would be to “calibrate” the controller to the generator by applying combinations or variations of real and complex loads to characterize the dynamic generator performance. This could be done automatically prior to each procedure as a startup step which would provide the most flexibility. In each case, default values would be established to provide acceptable performance and alternatives described above would enhance the ability to reduce false positive excessive arc events.
A device may be used perform the cutting or tissue reduction through RF energy-charged wires, with the RF energy being received from the RF electrosurgical generator. Critical to this cutting/reduction is the supply of adequate RF power density and load density. This adequate supply of RF power and load can be monitored by subsystems inside or outside the user instrument.
A user interface device is envisioned where RF energy is only delivered from the RF power source once adequate force is applied to the segmenting wires. The handle device is comprised of a connection interface to the segmenting wires. This handle device could slide within a housing device which would isolate the segmenting wire(s) from surrounding wire(s) and patient tissue. There could be a multitude of channels contained within the envisioned housing. The handle could contain a flexible, possibly spring loaded, RF contact switch where switch connection is only made once a large enough tension force is applied & maintained to the wires. An additional activation button could be present on the handle which would give the user positive control as to RF energy application to the segmenting wires (once adequate tension force is applied to the wires). The user would continue to pull the handle until segmentation/reduction of the tissue specimen is complete.
For the segmenting wire connection interface portion of the handle—easy connection/disconnection of each segmenting wire(s) is envisioned. This quick connect/disconnect could be accomplished by design where locking connection is achieved by simply plugging in the handle. Release of the segmenting wires could be achieved by a slide/push button release which quickly releases the plug-in auto locking mechanism. The handle connection interface could be comprised of the ‘J-hook’ feature where connection to the segmenting wire(s) can be accomplished by simply pushing to plug into the wire connection. Connection is maintained while the user applies the adequate tension force. After the segmentation/tissue reduction is complete—the handle and connected wires are pulled from the instrument. The now exposed connection point will allow the ‘J-hook’ connection to easily release/fall away now that they are not constrained within an instrument channel.
The handle distal end containing the connection interface could comprise of an insulated flexible & electrically conductive material, such as a thin brass sheet metal. This flexible portion of the handle unit could provide a unique ergonomic advantage to the user in that the applied tension force would not have to be applied in the exact direction of the pulled segmenting wires. The user could apply the tension via the handle in a variety of angles making the motion of operation better suited ergonomically to the user.
RF Enable with Tension Concept:
As noted earlier for the Segmentation Instrument-application of adequate power and load density is needed for optimal cutting or tissue reduction through RF energy-charged wires. For optimal cutting—the charged wires should be pre-tensioned so that intimate contact between the wires and the tissue specimen is ensured. To prevent inadvertent RF energy to the wires prior to their pre-tension an isolation switch or mechanism can be envisioned such that RF delivery is not possible prior to wire pre-tensioning. In an automated segmentation instrument—one could envision the pre-tension force being applied in a mechanical matter, such as a compression spring or constant force spring, or in an electromechanical matter with a motor. In either case an electrical isolation switch or patch can be applied at the point where the RF energy source is contacting the electrically conductive tensioning mechanism. This electrical isolation will prevent RF energy delivery to the tensioning mechanism (and wire(s)) until wire tension is initiated and, thus, removing the electrical isolation from RF energy/tensioning mechanism after the wire(s) pre-tension.
As described in the RF Enable concept, the charged wires should be pre-tensioned so that intimate contact between the wires and the tissue specimen is ensured. As an alternative to the RF Enable with Tension concept described above, several concepts will be described that use detection of movement of the tensioning mechanism ensure that tensioning of the wires has occurred.
Tensioning of the wires may be created by movement of the tensioning mechanism in a manner that provides a mechanical load on the wires pulling them against the tissue. This may be created by holding the tensioning mechanisms to apply the load as a step function, liner increase, exponential increase or other means to increase the load from an unloaded condition to a fully tensioned condition where the wires are pre-tensioned to provide the intimate contact. One method to ensure that the tensioning mechanism has successfully provided the load to the wires is to monitor the surface of the tensioning mechanism with an optical motion sensing component during the tensioning process. If movement of the tensioning mechanism is detected, then the tensioning mechanism is considered to have been released and the load applied to the wires. The optical motion sensors can measure the distance traveled by the tensioning mechanism which can in turn be used to calculate the size of the tissue specimen. For extremely large tissue specimens, the movement of the tensioning mechanisms may advance outward with a negative motion if the compressive forces of the wires around the tissue exceed the force being applied by the tensioning mechanisms. Any movement detected by the sensors can be considered a successful release of the tensioning mechanism and an applied load to the wires.
Another means of optical tensioning detection would be to use a motor that applies the tensioning force of the wires. The motor could use an encoder to detect movement of the motor and using the gear ratio, or ratio of linear translation per motor angular rotation or encoder counts, the distance travels can be calculated to ensure tension has been applied. This may be used in conjunction with a torque indication on the motor, or a the current level of the motor drive, to determine when the appropriate force has been applied.
Inductive proximity sensors are commonly used to sense how far away metal objects are. An inductive sensor runs high frequency current through a wire coil to create an oscillating electromagnetic magnetic field. As a metal object moves closer to the field, eddy currents are generated in the object which dampen the wire coil oscillation. By measuring the reduction in amplitude of the oscillation wave, the sensor can detect proximity of the object.
In this concept, an inductive proximity sensor is placed close to the spring coil or coils which are used as the tensioning mechanism. One sensor could be used that covers all springs or multiple sensors could be used, for example one per spring. A change in the attenuation of the signal could then be measured as one or more spring coils are retracted thereby sensing spring movement and/or location. Alternatively, when a spring is retracting, there is “chatter” in the positional measurement output from the sensor. This chatter is an up and down variation of the sensed position output over time during the spring movement but returns to a stable output once the spring movement has come to rest. This chatter could also be used to sense spring movement or potentially determine which springs have been released and moved versus the ones that have not.
An alternate method to the Inductance sensor concept would be to use a metal foil or conductive layer integrated into the lumen around the tensioning mechanisms. The conductive layer would be electrically isolated from the tensioning mechanism but electrically coupled to an interrogation circuit that applies an ac waveform between the foil and one or more tensioning mechanisms. As the tensioning mechanism moves, the capacitance between the mechanism and foil changes. The sensing circuit can utilize this change to detect movement of the tensioning mechanism. The conductive foil can be placed around each mechanism to sense the motion of an individual mechanism or around the all mechanisms to detect the change in capacitance from the parallel combination of the mechanisms.
When the tensioning mechanism, or springs, are released in the segmentation instrument, there is a vibration created from the spring retracting and shaking while doing so. A vibration sensor or sensors could be used to sense spring retraction. A piezo vibration sensor, a cantilever-beam accelerometer, a vibration sensor switch (spring coil shaking closes switch), or another sensor could be used.
Another method to determine tensioning could be to use an accelerometer to detect the shock detected with the spring contacting the tissue. This concept would take advantage of a step release of the tensioning mechanisms that are unloaded upon initial release. The released springs will pull the wires into the tissue with an abrupt stop which will be detected by the accelerometer. The four springs can have a slight offset in the release to provide separate shock events that can be independently detected by the accelerometer. This same accelerometer can be used to detect the end of cutting for each tensioning mechanism as the spring will travel unloaded after wire is pulled out of the tissue. The shock will occur when the spring reached the end of travel in the relaxed state.
To determine whether springs have retracted or how far springs have retracted, a window could be created to see the side of the spring coil and how many turns it has. By direct visual examination, it can be determined if a spring has released and/or how far the spring has retracted.
Alternatively, the spring coil could have a connection to a mechanical indicator such that if the coil rolled up, a dial or other visual indicator showed the spring release and/or how far the spring has coiled.
Alternatively, a magnetic sensor and/or switch or other electrical sensor could be employed to sense the spring release and/or how far the spring has coiled. This sensor could optionally provide a light or some other visual indicator to show the user under direct inspection information about spring retraction.
1. A tissue removal bag assembly, comprising: an inner bag layer having an interior surface and an exterior surface; an outer bag layer having an interior surface and an exterior surface, the outer bag layer coupled to the inner bag layer and forming a space between the exterior surface of the inner bag layer and the interior surface of the outer bag layer.
2. The assembly of embodiment 1, further comprising: a sensor exposed to the space, the sensor configured to detect pressure in the space.
3. The assembly of embodiment 1 or 2, further comprising: an inflation mechanism coupled to and configured to inflate the space between the inner bag layer and outer bag layer.
4. The assembly of embodiment 1-3, further comprising: a color changing indicator responsive to and configured to indicate a breach in the inner bag layer.
5. The assembly of embodiment 1-4, further comprising: a conductive deposition between the outer bag layer and the inner bag layer, the conductive deposition configured to indicate a breach in the inner bag layer.
6. The assembly of embodiment 1-5, further comprising: a fluid in the space.
7. The assembly of embodiment 1-6, further comprising: a sensor exposed to the space, the sensor configured to detect at least one of carbon dioxide or nitrous oxide.
8. The assembly of embodiment 1-7, further comprising: a vacuum loss indicator configured to indicate a loss of negative pressure between the outer bag layer and the inner bag layer.
9. The assembly of embodiment 8, wherein: the vacuum loss indicator comprises an expansion member, the expansion member configured to move from a compressed configuration to an expanded configuration in response to a loss of negative pressure between the outer bag layer and the inner bag layer.
10. The assembly of embodiment 1-9, further comprising: at least one of a hydrogel, a chemotherapy agent, or an absorbent material positioned between the outer bag layer and the inner bag layer.
11. The assembly of embodiment 1-10, further comprising: a plurality of sealed pockets positioned between the outer bag layer and the inner bag layer.
12. The assembly of embodiment 11, further comprising: a plurality of walls coupling the outer bag layer to the inner bag layer to form the plurality of sealed pockets.
13. The assembly of embodiment 11, further comprising: a third bag layer, the third bag layer having an inner wall, an outer wall, and a number of connecting walls coupling the inner wall and the outer wall and forming the plurality of sealed pockets.
14. The assembly of embodiment 11-13, wherein: at least one of the plurality of sealed pockets contains at least one of air, a fluid, a gel, a hydrogel, a thermosetting material, an absorbent material, a chemotherapy agent, or a color changing material.
15. The assembly of embodiment 1-10, further comprising: a third bag layer, the third bag layer having an inner wall, an outer wall, and a number of connecting walls coupling the inner wall and the outer wall and forming the plurality of sealed pockets.
16. The assembly of embodiment 15, wherein: the third bag layer is interior of the outer bag layer.
17. The assembly of embodiment 1-16, further comprising: a thermosetting material positioned interior of the outer bag layer and configured to solidify when exposed to bodily fluid.
18. The assembly of embodiment 17, wherein: the thermosetting material is configured to solidify within a period of time of exposure to the bodily fluid.
19. The assembly of embodiment 18, wherein: the period of time is one minute or less.
20. The assembly of embodiment 1-19, further comprising: a color changing indicator positioned interior of the outer bag layer, the color changing material having a material selected to change from a first color to a second color in response to exposure to at least one of nitrous oxide, carbon dioxide, or bodily fluid.
21. The assembly of embodiment 1-20, wherein: the outer bag layer has a first color; the inner bag layer has a second color; and wherein contact between the outer bag layer and the inner bag layer results in a third color observed.
22. A tissue segmentation device having at least one active electrode, a return electrode, a mechanical force application mechanism, a voltage sensor, a current sensor, and a controller. The controller is configured to control a power output of the segmentation device. The controller has a processing component, responsive to the voltage sensor and the current sensor, configured to execute the following: (a) derive a power factor of power applied to the at least one electrode; and (b) responsive to the deriving a power factor, assign a circuit status to a circuit comprising the at least one electrode, according to the following: IF (PF≈0) and ((Vrms/Irms)≥T), THEN the circuit status is “open”. IF (PF≈0) and ((Vrms/Irms)<T), THEN the circuit status is “short”. PF is the power factor. Vrms is the root mean square of a voltage associated with the power applied to the at least one electrode. Irms is the root mean square of a current associated with the power applied to the at least one electrode. T is a threshold value.
23. A controller for a tissue segmentation device having at least one active electrode, a return electrode, a voltage sensor, a current sensor, and a mechanical force application mechanism. The controller has a processing component, responsive to the voltage sensor and the current sensor, configured to execute the following: (a) derive a power factor of power applied to the at least one electrode; and (b) responsive to the deriving a power factor, assign a circuit status to a circuit comprising the at least one electrode according to the following: IF (PF≈0) and ((Vrms/Irms)≥T), THEN the circuit status is “open”. IF (PF≈0) and ((Vrms/Irms)<T), THEN the circuit status is “short”. PF is the power factor. Vrms is the root mean square of a voltage associated with the power applied to the at least one electrode. Irms is the root mean square of a current associated with the power applied to the at least one electrode. T is a threshold value.
24. A method of tissue segmentation. The method includes providing a tissue segmentation device having at least one active electrode, a return electrode, a mechanical force application mechanism, a voltage sensor, and a current sensor. The method includes deriving a power factor of power applied to the at least one electrode, and responsive to deriving a power factor, assigning a circuit status to a circuit comprising the at least one electrode according to the following: IF (PF≈0) and ((Vrms/Irms)≥T), THEN the circuit status is “open”; IF (PF≈0) and ((Vrms/Irms)<T), THEN the circuit status is “short”. PF is the power factor. Vrms is the root mean square of a voltage associated with the power applied to the at least one electrode. Irms is the root mean square of a current associated with the power applied to the at least one electrode. T is a threshold value.
25. A tissue segmentation device. The device has at least one active electrode, a return electrode, a mechanical force application mechanism, a voltage sensor, a current sensor, and a controller. The controller is configured to control a power output of the segmentation device. The controller has a processing component, responsive to the voltage sensor and the current sensor, configured to execute the following: (a) derive an impedance to power applied to the at least one electrode; and (b) responsive to the deriving the impedance, assign a circuit status to a circuit comprising the at least one electrode, according to the following: IF (Z>T1), THEN the circuit status is “open”; and IF (Z<T2), THEN the circuit status is “short”; where Z is the impedance; T1 is a first threshold value; and T2 is a second threshold different from the first threshold value.
Each of the various elements disclosed herein may be achieved in a variety of manners. This disclosure should be understood to encompass each such variation, be it a variation of an embodiment of any apparatus embodiment, a method or process embodiment, or even merely a variation of any element of these. Particularly, it should be understood that the words for each element may be expressed by equivalent apparatus terms or method terms-even if only the function or result is the same. Such equivalent, broader, or even more generic terms should be considered to be encompassed in the description of each element or action. Such terms can be substituted where desired to make explicit the implicitly broad coverage to which this invention is entitled.
As but one example, it should be understood that all action may be expressed as a means for taking that action or as an element which causes that action. Similarly, each physical element disclosed should be understood to encompass a disclosure of the action which that physical element facilitates. Regarding this last aspect, the disclosure of a “cutting mechanism” should be understood to encompass disclosure of the act of “cutting”—whether explicitly discussed or not—and, conversely, were there only disclosure of the act of “cutting”, such a disclosure should be understood to encompass disclosure of a “cutting mechanism”. Such changes and alternative terms are to be understood to be explicitly included in the description.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention defined by the claims. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
The present application for patent is a Continuation of U.S. patent application Ser. No. 16/586,719, titled “TISSUE SPECIMEN REMOVAL DEVICE, SYSTEM AND METHOD,” filed Sep. 27, 2019, which in turn is a Continuation-in-Part of U.S. patent application Ser. No. 16/381,661, entitled “TISSUE SPECIMEN REMOVAL DEVICE, SYSTEM AND METHOD,” filed Apr. 11, 2019, which claims priority to Provisional Application No. 62/656,251, entitled “TISSUE SPECIMEN REMOVAL DEVICE, SYSTEM AND METHOD,” filed Apr. 11, 2018, and also claims priority to Provisional Application No. 62/738,652, entitled “TISSUE SPECIMEN REMOVAL DEVICE, SYSTEM AND METHOD,” filed Sep. 28, 2018 and assigned to the assignee hereof and hereby expressly incorporated by reference herein. This application is related to U.S. Pat. No. 9,649,147 issued May 16, 2017 and entitled “Electrosurgical Device and Methods,” and U.S. Pat. No. 9,522,034 issued Dec. 20, 2016 and entitled “Large Volume Tissue Reduction and Removal System and Method,” the entire disclosures of which are hereby incorporated by reference for all proper purposes, as if fully set forth herein. While various novel features are described herein, they can be used alongside or in conjunction with the inventions and disclosure set forth in the patents mentioned above. Therefore, the relevant text, figures and other disclosure from these prior patents are included in the present disclosure for context, background, and where necessary, incorporation into aspects of the inventions described herein.
Number | Date | Country | |
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62738652 | Sep 2018 | US | |
62656251 | Apr 2018 | US |
Number | Date | Country | |
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Parent | 16586719 | Sep 2019 | US |
Child | 18751243 | US |
Number | Date | Country | |
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Parent | 16381661 | Apr 2019 | US |
Child | 16586719 | US |