Patent Application
20250195090
The present disclosure pertains generally to medical devices and methods of their use. More particularly, the present invention pertains to aspiration and thrombectomy devices and methods of use thereof.
Blood clots (thrombi) can form in various parts of the body and can pose a serious health risk. For instance, blood clots can block blood flow and/or lead to tissue damage, organ dysfunction, or life-threatening conditions like stroke or heart attack. Thrombectomy is a medical procedure used to remove blood clots from blood vessels to restore blood flow and prevent further complications.
Various types of catheter-based thrombectomy devices have been developed to aid in the removal of thrombotic material. Such devices are typically inserted into the affected blood vessel through a small incision or artery access point. Catheter-based thrombectomy devices include mechanical thrombectomy devices, rheolytic thrombectomy devices, and others (e.g., ultrasound-assisted devices).
Mechanical thrombectomy devices can implement various types of mechanical components to engage with and remove thrombotic material. For instance, stent retrievers and clot retriever baskets are designed for navigation through vasculature to the site of a clot, deployment at the clot site to cause the stent retriever or clot retriever basket to entrap the clot, and withdrawal through the vasculature to facilitate clot removal. As another example, suction-based thrombectomy devices use negative pressure to aspirate clots from blood vessels (e.g., via a catheter with a distal tip to be placed near the clot prior to activation to draw the clot into a collection chamber, where it is trapped and removed). As yet another example, rotational thrombectomy devices employ rotational mechanisms to fragment and remove clots (e.g., a rotating wire or catheter tip for creating shear forces that break down clots), allowing the fragments to be cleared by the body or using aspiration or other techniques.
Rheolytic thrombectomy devices employ mechanisms that rely on high-velocity jets to break down and remove thrombotic material. Rheolytic thrombectomy mechanisms may be positioned on catheters (e.g., at or near the distal tip) and can utilize saline solution, or a mixture of saline and the patient's own blood, to create high-velocity jets for direction toward clots to generate shear forces that disrupt the clot's structure. The jetted fluid can cause fragmentation of the clot, and the fragments may then be cleared naturally from the body or by aspiration techniques.
Some thrombectomy devices employ aspects of suction-based thrombectomy devices and rheolytic thrombectomy devices. For instance, some thrombectomy devices utilize a saline jet positioned at or near a distal tip of an aspiration catheter, allowing for aspiration of clot fragments as the jetted saline macerates the clot (e.g., thrombus and/or soft emboli).
Catheter-based thrombectomy devices sometimes experience catheter clogging during clot removal operations. Catheter clogging can result from attempting to aspirate large or tough clots that can be resistant to fragmentation (e.g., due to calcification or fibrin richness). Catheter clogging during clot removal operations can often go undetected (e.g., unless the clinician pays close attention to canister blood flow). When the catheter is clogged, suction at the distal tip of the catheter can be lost, and fluid can be sprayed out from the distal tip of the catheter (when a saline jet is present). Fluid released from the distal tip of the catheter can cause cell lysis and/or displacement of blood cells. Additionally, fluid released from the distal tip of the catheter can cause clot material to be pushed away from or spin about the distal tip of the catheter, which can further complicate and/or prolong a clot removal procedure.
The subject matter disclosed herein is not limited to embodiments that operate only in environments such as those described above. Rather, this background is only provided to illustrate one example technology area where some embodiments described herein may be practiced.
At least some disclosed embodiments provide a thrombectomy system that includes (i) an aspiration catheter configured for advancement through vasculature of a subject to facilitate clot removal from the vasculature of the subject; (ii) a fluid jet proximate to a distal end of the aspiration catheter; and (iii) a flow direction sensor positioned on the aspiration catheter proximate to the fluid jet. The flow direction sensor is configured to detect a flow direction of fluid at a distal region of the aspiration catheter during operation of a clot removal state of the thrombectomy system. The flow direction of the fluid at the distal region of the aspiration catheter
At least some disclosed embodiments provide a thrombectomy system that includes (i) an aspiration catheter configured for advancement through vasculature of a subject to facilitate clot removal from the vasculature of the subject; (ii) a fluid jet proximate to a distal end of the aspiration catheter; and (iii) a flow sensor positioned on the aspiration catheter proximal to the fluid jet. The flow sensor is configured to detect a flow rate of fluid within an aspiration lumen of the aspiration catheter during operation of a clot removal state of the thrombectomy system. The flow rate of the fluid within the aspiration lumen indicates a clog state of the aspiration catheter.
This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an indication of the scope of the claimed subject matter.
Various objects, features, characteristics, and advantages of the invention will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings and the appended claims, all of which form a part of this specification. In the Drawings, like reference numerals may be utilized to designate corresponding or similar parts in the various Figures, and the various elements depicted are not necessarily drawn to scale, wherein:
As indicated hereinabove, catheter clogging incidents in catheter-based thrombectomy systems can often go undetected. For example, many aspiration catheters lack a mechanism to determine whether a catheter of a thrombectomy system is clogged during clot removal operations. To detect catheter clogging during clot removal operations, users often rely on careful observation of canister blood flow, which can detract from the user's attention to other aspects of a clot removal operation. Failure to detect a clogged catheter during a clot removal operation can result in blood lysis, displacement of blood cells, clot displacement, and/or other negative outcomes for patients.
The present disclosure pertains to systems, devices, and techniques for detecting catheter clogging in thrombectomy systems.
For example, a thrombectomy system may include a flow direction sensor position near the fluid jet at the distal end of the aspiration catheter. The flow direction sensor may take on various forms, such as an ultrasonic flow meter, an electromagnetic flow meter, a temperature-based flow meter, an optical-based flow meter (e.g., to determine hemoglobin levels), and/or others. The flow direction sensor can be configured to detect the flow direction of fluid at the distal region of the aspiration catheter. Detection of flow in a proximal direction (e.g., into and/or through the aspiration catheter toward the canister) can indicate the absence of catheter clogging. In contrast, detection of flow in a distal direction (e.g., outward from the aspiration catheter and away from the canister) can indicate the presence of catheter clogging. Based on a catheter clogging state indicated via the flow direction sensor, the thrombectomy system can selectively deactivate clot removal operations and/or present an alert to a user (e.g., directing the user to disable the clot removal state, or advising the user that a clog may be present).
An additional or alternative flow meter may be positioned within the aspiration lumen of the aspiration catheter of the thrombectomy system. The flow meter may detect the flow rate of fluid within the aspiration lumen during clot removal operations. The flow rate within the aspiration lumen can indicate the clog state of the aspiration catheter. For instance, detection of a flow rate below certain levels (e.g., after a startup routine or time period, or after initially reaching a minimum flow rate) can indicate the presence of catheter clogging, whereas detection of a flow rate above certain levels (e.g., after the startup routine, time period, or reaching the minimum flow rate) can indicate the absence of catheter clogging. Based on the catheter clogging state indicated via the flow meter, the thrombectomy system can selectively deactivate clot removal operations and/or present an alert to a user (e.g., directing the user to disable the clot removal state, or advising the user that a clog may be present).
In some instances, implementing a clog detection system on a thrombectomy device, as described herein, may provide various advantages, such as reducing the duration of thrombectomy operations, reducing clot movement/displacement during thrombectomy operations, and others. Such advantages can beneficially facilitate improved patient outcomes.
Although examples discussed herein focus, in at least some respects, on implementing a clog detection system on an aspiration catheter that includes a fluid jet at the distal region, the techniques and/or components discussed herein may be implemented on aspiration catheters that omit fluid jets, and/or on other types of catheter-based devices, even outside of the domain of thrombectomy.
The following discussion relates to an example catheter-based thrombectomy device that implements aspiration aspects and rheolytic aspects and that may comprise or be used to implement at least some disclosed embodiments. As noted above, the principles disclosed herein may be implemented in conjunction with other types of catheter-based thrombectomy systems.
A system 100 for aspirating thrombus is illustrated in
As shown in
A spike 116 for coupling to a fluid source (e.g., saline bag, saline bottle) allows fluid to enter through an extension tubing 118 and flow into a supply tube 119. An optional injection port allows injection of materials or removal of air. A cassette 121 having a moveable piston 122 is used in conjunction with a mechanical actuator 123 of the pump 101. Fluid is pumped into an injection tube 124 from action of the cassette 121 as applied by the actuator 123 of the pump 101. A male luer 126, hydraulically communicating with the catheter supply lumen 114, via the injection tube 124, is configured to attach to the female luer 113 of the y-connector 110.
Accessories are illustrated that are intended for applying a vacuum source, such as a syringe 130 having a plunger 132 and a barrel 134, to the aspiration lumen 106 of the catheter 102. The syringe 130 is attached to a vacuum line 136 via the luer 140 of the syringe 130. A stopcock 138 may be used on the luer 140 to maintain the vacuum, or alternatively, the plunger 132 may be a locking variety of plunger that is configured to be locked in the retracted (vacuum) position. A male luer 142 at the end of the vacuum line 136 may be detachably secured to the female luer 115 of the y-connector 110 of the aspiration catheter 102. As shown in more detail in
A foot pedal 160 is configured to operate a pinch valve 162 for occluding or opening the vacuum line 136. The foot pedal 160 comprises a base 164 and a pedal 166 and is configured to be placed in a non-sterile area, such as on the floor, under the procedure table/bed. The user steps on the pedal 166 causing a signal to be sent along a cable 168 which is connected via a plug 170 to an input jack 172 in the pump 101. The vacuum line 136 extends through a portion of the pump 101. The circuit board 158 of the pump may include a controller 174 configured to receive one or more signals indicating on or off from the foot pedal 160. The controller 174 of the circuit board 158 may be configured to cause an actuator 176 carried by the pump 101 to move longitudinally to compress and occlude the vacuum line 136 between an actuator head 178 attached to the actuator 176 and an anvil 180, also carried by the pump 101. By stepping on the pedal 166, the user is able to thus occlude the vacuum line 136, stopping the application of a negative pressure. In some embodiments, as the pedal 166 of the foot pedal 160 is depressed, the controller may be configured to open the pinch valve 162.
The pressure transducer 144 thus senses a negative pressure and sends a signal, causing the controller to start the motor of the pump 101. As the effect via the electronics is substantially immediate, the motor starts pumping almost immediately after the pedal 166 is depressed. As the pedal 166 of the foot pedal 160 is released, the controller 174 then causes the pinch valve 162 to close. The pressure transducer 144 thus senses that no negative pressure is present and the controller 174 causes the motor of the pump 101 to shut off. Again, the effect via the electronics is substantially immediate, and thus the motor stops pumping almost immediately after the pedal 166 is depressed. During sterile procedures, the main interventionalist is usually “scrubbed” such that the hands only touch items in the sterile field. However, the feet/shoes/shoe covers are not in the sterile field. Thus again, a single user may operate a switch (via the pedal 166) while also manipulating the catheter 102 and guidewire 148. However, this time, it is the sterile field hands and non-sterile field feet that are used. Alternatively, the foot pedal 160 may comprise two pedals, one for occlude and one for open. In an alternative foot pedal embodiment, the pedal 166 may operate a pneumatic line to cause a pressure activated valve or a cuff to occlude and open the vacuum line 136, for example, by forcing the actuator head 178 to move. In another alternative embodiment, the pedal 166 may turn, slide, or otherwise move a mechanical element, such as a flexible pull cable or push rod that is coupled to the actuator 176, to move the actuator head 178. The cable 168 may be supplied sterile and connected to the base 164 prior to a procedure. The occlusion and opening of the vacuum line 136 thus acts as an on and off switch for the pump 101 (via the pressure sensor 144). The on/off function may thus be performed by a user whose hands can focus on manipulating sterile catheters, guidewires, and accessories, and whose foot can turn the pump on and off in a non-sterile environment. This allows a single user to control the entire operation or the majority of operation of the system 100 for aspirating thrombus. This can be an advantage in terms of a rapid, synchronized procedure, but is also helpful in laboratories where additional assistants are not available. The actuator 176 and anvil 180 may be controlled to compress the vacuum line 136 with a particular force, and the actuator 176 may be controlled to move at a particular speed, either when compressing or when removing compression. Speed and force control allows appropriate response time but may also be able to add durability to the vacuum line 136, for example, by not over-compressing. The foot pedal 160 may communicate with the pinch valve 162 via a wired connection through the pump 101 or may communicate with the pinch valve 162 wirelessly. Additionally, or alternatively, the pump may be controlled by buttons 184 or other user interfaces.
It should be noted that in certain embodiments, the pinch valve 162 and the foot pedal 160 may be incorporated for on/off operation of the pinch valve 162 on the vacuum line 136, without utilizing the pressure sensor 144. In fact, in some embodiments, the pressure sensor 144 may even be absent from the system 100 for aspirating thrombus, the foot pedal 160 being used as a predominant control means.
Turning to
A system 200 for aspirating thrombus is illustrated in
Although examples provided herein focus, in at least some respects, on an aspiration catheter 102 that includes a single orifice 194, an aspiration catheter of a system (e.g., 100 or 200) can include any quantity of orifices through which fluid may pass to form any quantity of fluid jets. For example, a system 100 or 200 for aspirating thrombus can include a quantity of orifices (for forming fluid jets) within a range of 1 to 10, or within a range of 2 to 8, or within a range of 3 to 6.
Although
Furthermore,
The orifice(s) of an aspiration catheter 102 of a system (e.g., 100 or 200) for providing fluid jets (i.e., “jet-forming” orifices) may be implemented with various sizes or shapes in different embodiments. In one example, an orifice may comprise a circular hole with a diameter between 0.03 mm (0.001 inches) and 0.15 mm (0.006 inches), or between about 0.0508 mm (0.002 inches) and about 0.1016 mm (0.004 inches), or about 0.0787 mm (0.0031 inches). The diameter of the supply lumen 114 may be between about 0.3048 mm (0.012 inches) and about 0.4826 mm (0.019 inches), or between about 0.3556 mm (0.014 inches and about 0.4318 mm (0.017 inches), or about 0.3937 mm (0.0155 inches). As another example, an orifice may comprise a rectangular hole with each side thereof having a length between 0.02 mm (0.0008 inches) and 0.20 mm (0.008 inches). In some implementations, the total cross-sectional area of all jet-forming orifices of an aspiration catheter of a system is between 0.002 mm{circumflex over ( )}2 and 0.02 mm{circumflex over ( )}2, or between 0.003 mm{circumflex over ( )}2 and 0.015 mm{circumflex over ( )}2, or between 0.005 mm{circumflex over ( )}2 and 0.01 mm{circumflex over ( )}2. In some embodiments, pressure measured at the deliver location of each jet-forming orifice during operation of the system (e.g., 100 or 200) is between 400 psi (2.6 MPa) and 2,000 psi (13.8 MPa), or between 500 psi (3.4 MPa) and 2,000 psi (13.8 MPa), or between 600 psi (4.1 MPa) and 1,750 psi (12.1 MPa).
In some implementations, the diameter of the aspiration lumen 106 is within a range of 2 mm (0.08 inches) to 4 mm (0.16 inches). The orifice 194 may be set proximally of the open distal end 107 by a set amount. For example, orifice 194 can be set proximally of the open distal end 107 by about 0.040″ (inches), and in one configuration by 0.051″+−0.003″ or by another desired amount. For example, orifice 42 can be set proximally of the open distal end 107 by approximately 0.035″, 0.036″, 0.037″, 0.038″, 0.039″, 0.040″, 0.041″, 0.042″, 0.043″, 0.044″, 0.045″, 0.046″, 0.047″, 0.048″, 0.049″, 0.050″, 0.051″, 0.052″, 0.053″, 0.054″, 0.055″, 0.056″, 0.057″, 0.058″, 0.059″, 0.060″, or a range defined by any two of the foregoing. In still other configurations, the open distal end 107 can be set proximally of the open distal end 107 by about 0.01″ to about 50″.
In still another configuration a diameter of the aspiration lumen 106 is about 0.075″ (inches) to about 0.177″ (inches), the orifice 194 (and so a distal end of the supply tube 186) can be set proximally of open distal end 107 about 12″ (inches). In still another configuration a diameter of the aspiration lumen 106 is about 0.075″ (inches), the orifice 194 (and so a distal end of the supply tube 186) can be set proximally of open distal end 107 about 0.035″ (inches) to about 0.060″ (inches). In still another configuration, the orifice 194 (and so a distal end of the supply tube 186) can be set proximally of open distal end 107 about 0.010″ (inches) to about 50″ (inches) where the catheter 102 has a catheter size ranging from about 3 Fr to about 50 Fr. In still another configuration, the orifice 194 (and so a distal end of the supply tube 186) can be set proximally of open distal end 107 about 0.010″ (inches) to about 0.200″ (inches), from about 0.010″ (inches) to about 2″ (inches), 0.010″ (inches) to about 40″ (inches), 0.010″ (inches) to about 50″ (inches), or a range defined by any two of the foregoing. In still other configurations, the orifice 194 (and so a distal end of the supply tube 186) can be set proximally of open distal end 107 based upon Table 1:
In another configuration, the orifice 194 (and so a distal end of the supply tube 186) can be set proximally of open distal end 107 about 0.010″ (inches) to about 0.200″ (inches) for a catheter having a catheter size ranging from about 3 Fr to about 8 F. In another configuration, the orifice 194 (and so a distal end of the supply tube 186) can be set proximally of open distal end 107 about 0.010″ (inches) to about 2″ (inches) for a catheter having a catheter size ranging from about 9 Fr to about 11 Fr. In another configuration, the orifice 194 (and so a distal end of the supply tube 186) can be set proximally of open distal end 107 about 0.010″ (inches) to about 40″ (inches) for a catheter having a catheter size ranging from about 12 Fr to about 16 F. In another configuration, the orifice 194 (and so a distal end of the supply tube 186) can be set proximally of open distal end 107 about 0.010″ (inches) to about 50″ (inches) for a catheter having a catheter size ranging from about 17 Fr to about 26 F. In other configurations, the ranges can include any combination of a range defined by any two of the foregoing proximal location of the orifice 194 with a range defined by any two of the foregoing catheter sizes.
A pump set 210 (e.g., tubing set) is configured to hydraulically couple the supply lumen 114 to a pump within a saline drive unit (SDU) 212, for injecting pressurized fluid (e.g., saline, heparinized saline) through the supply lumen 114. Suction tubing 214, comprising sterile suction tubing 216 and non-sterile suction tubing 217, is configured to hydraulically couple a vacuum canister 218 to the aspiration lumen 106. A filter 220 may be carried in-line on the suction tubing 214, for example, connected between the sterile suction tubing 216 and the non-sterile suction tubing 217, or on the non-sterile suction tubing 217. The filter 220 is configured to capture large elements such as large pieces of thrombus or emboli.
The pump set 210 includes a saline spike 221 for connection to a port 222 of a saline bag 224, and an inline drip chamber 226 for visually assessing the movement of saline, as well as keeping air out of the fluid being injected. The saline bag 224 may be hung on an IV pole 227 on one or more hooks 228. A pressure sensor 230 such as a vacuum sensor may be used within any lumen of the pump set 210, the suction tubing 214, the supply lumen 114 or aspiration lumen 106 of the catheter 202, or any other component which may see fluid flow. Additional or alternative pressure sensors may be implemented to measure pressure associated with the vacuum canister 218. The pressure sensor 230 is shown in
In the example of
In use, a user connects a first connector 256 at a first end 258 of the non-sterile suction tubing 217 to a port 259 on the lid 260 of the canister 218, and connects a second connector 261 at a second end 262 of the non-sterile suction tubing 217 to a vacuum pump input 264 in the SDU 212. A vacuum pump 266 may be carried within the SDU 212 in order to maintain a vacuum/negative pressure within the canister 218. Alternatively, the vacuum inside the canister 218 may be maintained manually, without a vacuum pump, by evacuating the canister 218 via one or more additional ports 268. A user connects a first connector 270 of the sterile suction tubing 216 to an aspiration luer 271 of the aspiration catheter 202 (similar to luer 115), and connects the second connector 272 of the sterile suction tubing 216 to port 274 in the lid 260 of the canister 218. Connector 236 is then coupled to the mating receptacle 237 in the SDU 212 for communication with the control 233 and/or the pressure sensor 230. For instance, the connector 236 can be snapped into mating receptacle 237 in the SDU 212 for communication with elements of the control 233 and/or for communication with the pressure sensor 230, either via cable 234, and/or additional cables or wires. Alternatively, the connector 236 may couple to the mating receptacle 237 by clipping, friction fitting, vacuum fitting, or other means.
After allowing saline to purge through the supply tube 276, cassette 278, and injection tube 279 of the pump set 210, the user connects the luer connector 280 of the pump set 210 to a luer 282 of the aspiration catheter 202 (similar to luer 113). The cassette 278 (similar to cassette 121) is then attached to a saddle 283 in the SDU 212. The saddle 283 is configured to reciprocate a piston to inject the saline from the IV bag 224 at high pressure, after the cassette 278 is snapped in place, keeping the internal contents (e.g., saline) sterile. Systems configured for performing this type of sterile injection of high-pressure saline are described in U.S. Pat. No. 9,883,877, issued Feb. 6, 2018, and entitled, “Systems and Methods for Removal of Blood and Thrombotic Material”, which is incorporated by reference in its entirety for all purposes. The SDU 212 is enclosed within a case 284 and a case lid 285. The controller 235 may reside on a circuit board 286. Noise from a motor 287 controlling the saddle 283 and from the vacuum pump 266 may be abated by internal foam sections 288, 289. The saddle 283 may be moved directly by the motor 287, or may be moved with pneumatics, using a cycled pressurization. An interface panel 290 provides one or more switches 297 and the display 238. Alternatively, the cassette 121 may couple to the saddle 283 by clipping, friction fitting, vacuum fitting, or other means.
The aspiration catheter 702 of
The aspiration catheter 702 of
As noted above, while the clot removal state is active, the aspiration catheter 702 can sometimes become clogged with clot material. Users may experience difficulty in determining whether the aspiration catheter 702 has become clogged during a clot removal operation. Accordingly, the thrombectomy system 700 of
In the example of
During clot removal, the emission and detection of ultrasonic signals 728 between ultrasonic transducer 722 and ultrasonic transducer 724 can be used to determine whether the aspiration catheter 702 is clogged (e.g., with clot material). The flow of fluid through the distal region of the aspiration catheter 702 influences the time it takes for an ultrasonic signal 728 emitted by one ultrasonic transducer to traverse the interior of the aspiration catheter 702 to reach the other ultrasonic transducer. For instance, because of the distal-proximal offset of the ultrasonic transducers 722 and 724, fluid flow through the aspiration catheter 702 in the proximal direction (indicated by arrow 730 in
In some implementations, the thrombectomy system 700 may selectively remain in the clot removal state in response to determining that the emission/detection information associated with the flow direction sensor 720 indicates that fluid is flowing at the distal region of the aspiration catheter 702 in the proximal direction (indicated by arrow 730 in
In some implementations, the thrombectomy system 700 may selectively deactivate the clot removal state and/or enter a passive state in response to determining that the emission/detection information associated with the flow direction sensor 720 indicates that fluid is flowing at the distal region of the aspiration catheter 702 in the distal direction (indicated by arrow 730 in
Although
As one example,
In the example of
For example,
Other than Doppler shift techniques, the flow direction sensor 820 can utilize other types of optical detection techniques to facilitate clog state detection for the thrombectomy system 800. For example, in some implementations, the light 828 emitted by the light emitter 822 and detected by the light detector 824 is used to facilitate measurement of analytes present in blood (“blood analytes”). The concentration of blood analytes in the fluid passing through the distal region of the aspiration catheter 802 can indicate the flow direction of the fluid.
For example, during operation of the clot removal state in the absence of a catheter clog, the blood analyte measurements of the fluid passing through the propagation path of the light 828 between the light emitter 822 and the light detector 824 (positioned as shown in
Conversely, during operation of the clot removal state in the presence of a catheter clog, the blood analyte measurements of fluid passing through the propagation path of the light 828 between the light emitter 822 and the light detector 824 (positioned as shown in
Thus, analyte concentration in the fluid passing through the propagation path between the light emitter 822 and the light detector 824 can indicate whether a clog is present in the aspiration catheter 802. When the measured analyte concentration satisfies one or more conditions (e.g., a threshold), the system can determine that no catheter clog is present and remain in the clot removal state (e.g., according to decision block 834 and action block 836 of
Various analytes can be measured via the light emitter 822 and the light detector 824 to facilitate clog state detection of the thrombectomy system 800 as described above. For example, hemoglobin is associated with particular absorption features within a range of about 535 nm to about 580 nm, such as absorption peaks for oxygenated hemoglobin of about 540 nm and 575-576 nm and an absorption peak for deoxygenated hemoglobin within a range of about 555 nm to about 560 nm. Thus, in some implementations, the light emitter 822 is configured to emit light 828 of one or more known wavelengths that include absorption peaks associated with hemoglobin, and attenuation coefficients of the light 828 detected by the light detector 824 can be analyzed to provide an estimated hemoglobin concentration in the fluid traversed by the light 828. As noted above, the estimated hemoglobin concentration can indicate whether or not a catheter clog is present and can trigger different actions.
Additional or alternative blood analytes associated with known light absorption or emission characteristics can be measured via the flow direction sensor 820 to facilitate determination of catheter clog state for the thrombectomy system 800 (e.g., bilirubin, porphyrins, and/or others). In some implementations, a flow direction sensor can utilize non-optical techniques to facilitate analyte measurement indicating catheter clog state detection, such as electrode-based, electromechanical sensors-based, and/or enzyme-based methods (e.g., to measure blood glucose levels, lactate levels, cholesterol levels, urea levels, creatinine levels, pH levels, potassium levels, sodium levels, carbon dioxide levels, bilirubin levels, and/or others).
If a catheter clog is not present, the thrombectomy system 900 can remain in the clot removal state (indicated by the “No” arrow extending from decision block 934 toward action block 936 in
The photonic device 922 of
Another example technique for detecting fluid flow direction associated with an aspiration catheter of a thrombectomy system utilizes temperature measurements.
The temperature sensor 1022 of
Conversely, during operation of the clot removal state in the presence of a catheter clog, the temperature of fluid passing the temperature sensor 1022 (positioned as shown in
Thus, the temperature of the fluid passing the temperature sensor 1022 can indicate whether a clog is present in the aspiration catheter 1002. When the measured temperature satisfies one or more conditions (e.g., a threshold, such as about 37° C.), the system can determine that no catheter clog is present and remain in the clot removal state (e.g., according to decision block 1034 and action block 1036 of
As another example,
In the example of
As fluid flows through the aspiration catheter 1102 and the magnetic field formed by the coils 1122 and 1124, a voltage signal (e.g., electromotive force (EMF)) may be induced across the electrodes 1128 (e.g., perpendicular to both the direction of the magnetic field and the direction of fluid flow). The induced voltage can indicate the flow rate of the fluid passing through the aspiration catheter 1102, and the polarity of the induced voltage can indicate the direction of the fluid passing through the aspiration catheter 1102. Thus, while operating in a clot removal state, the flow direction sensor 1120 can indicate the direction of flow through the distal region of the aspiration catheter 1102, which can indicate whether the aspiration catheter 1102 is clogged (e.g., by clot material).
For example,
In some implementations, flow sensors that determine flow rate, regardless of flow direction, may be utilized to estimate/determine the clog state of an aspiration catheter of a thrombectomy system. For instance,
As fluid flows past the bluff body 1222 within the aspiration catheter 1202, vortices 1228 are alternately shed on either side of the bluff body 1222. The shedding frequency is proportional to the flow rate of the fluid. The pressure sensor 1224 can detect vortices 1228 shed via the bluff body 1222 and can therefore enable determination of the vortex shedding frequency, providing an indication of the flow rate of the fluid within the aspiration catheter 1202.
When the measured flow rate satisfies one or more conditions, such as exceeding threshold flow rate levels, the thrombectomy system 1200 can determine that no clog is present in the aspiration catheter 1202. This is shown in
When the measured flow rate fails to satisfy the condition(s), the thrombectomy system 1200 can determine that a clog is present in the aspiration catheter 1202. This is shown in
As another example,
The temperature sensors 1322 can include a first temperature sensor that measures the temperature of the fluid within the aspiration catheter 1302 and a second temperature sensor that is actively heated via an electrical current to maintain a predefined temperature offset between the first and second temperature sensors. The first and second temperature sensors can be placed within close proximity to one another. Fluid flowing past the plurality of temperature sensors 1322 exhibits a cooling effect on the plurality of temperature sensors 1322, which can cause changes to the electrical current applied to the second temperature sensor to maintain the predefined temperature offset. The electrical current applied to the second temperature sensor to compensate for the cooling effect brought about by fluid flow is proportional to the flow rate of fluid within the aspiration catheter 1302. Thus, the electrical current applied to the second temperature sensor can provide an indication of the flow rate of fluid within the aspiration catheter 1302. In an alternative embodiment, the electrical current applied to the second temperature sensor can be held constant, and the temperature differential between the two temperature sensors can indicate flow rate. In another alternative embodiment, a temperature sensor can be positioned proximal to an actively heated temperature sensor, which can enable the proximal temperature sensor to measure heat dissipation characteristics, which can indicate flow rate.
When the measured flow rate satisfies one or more conditions, such as exceeding threshold flow rate levels, the thrombectomy system 1300 can determine that no clog is present in the aspiration catheter 1302. This is shown in
When the measured flow rate fails to satisfy the condition(s), the thrombectomy system 1300 can determine that a clog is present in the aspiration catheter 1302. This is shown in
As yet another example,
As fluid flows through the restrictive element 1428, the velocity of the fluid increases, causing a pressure difference on different sides of the restrictive element 1428 (e.g., a pressure drop from the distal side to the proximal side when flow is in the proximal direction, indicated by arrow 1430 in
When the measured flow rate satisfies one or more conditions, such as exceeding threshold flow rate levels, the thrombectomy system 1400 can determine that no clog is present in the aspiration catheter 1402. This is shown in
When the measured flow rate fails to satisfy the condition(s), the thrombectomy system 1400 can determine that a clog is present in the aspiration catheter 1402. This is shown in
Embodiments disclosed herein can include those in the following numbered clauses:
Clause 1. A thrombectomy system, comprising: an aspiration catheter configured for advancement through vasculature of a subject to facilitate clot removal from the vasculature of the subject; a fluid jet proximate to a distal end of the aspiration catheter; and a flow direction sensor positioned on the aspiration catheter proximate to the fluid jet, wherein the flow direction sensor is configured to detect a flow direction of fluid at a distal region of the aspiration catheter during operation of a clot removal state of the thrombectomy system, wherein the flow direction of the fluid at the distal region of the aspiration catheter indicates a clog state of the aspiration catheter.
Clause 2. The thrombectomy system of clause 1, wherein the flow direction sensor comprises an ultrasonic flow meter that includes a plurality of ultrasonic transducers.
Clause 3. The thrombectomy system of clause 1, wherein the flow direction sensor comprises an optical flow sensor that includes a light emitter and a light detector.
Clause 4. The thrombectomy system of clause 3, wherein the light emitter and the light detector are positioned angularly offset about a wall of the aspiration catheter.
Clause 5. The thrombectomy system of clause 1, wherein the flow direction sensor comprises a temperature sensor.
Clause 6. The thrombectomy system of clause 5, wherein the temperature sensor comprises a micro-electromechanical system (MEMS) thermocouple.
Clause 7. The thrombectomy system of clause 1, wherein the flow direction sensor comprises an electromagnetic flow meter that includes a plurality of coils and a plurality of electrodes.
Clause 8. The thrombectomy system of clause 1, wherein the thrombectomy system is configured to present an alert on a user interface associated with the thrombectomy system after determining that the flow direction of the fluid at the distal region of the aspiration catheter during operation of the clot removal state satisfies one or more conditions.
Clause 9. The thrombectomy system of clause 8, wherein the alert comprises a directive to deactivate the clot removal state of the thrombectomy system.
Clause 10. The thrombectomy system of clause 8, wherein the alert comprises an indication of clogging of the aspiration catheter.
Clause 11. The thrombectomy system of clause 8, wherein the one or more conditions comprise the flow direction of the fluid at the distal region of the aspiration catheter during operation of the clot removal state indicating fluid flow in a distal direction.
Clause 12. The thrombectomy system of clause 1, wherein the thrombectomy system is configured to selectively deactivate the clot removal state after determining that the flow direction of the fluid at the distal region of the aspiration catheter during operation of the clot removal state satisfies one or more conditions.
Clause 13. The thrombectomy system of clause 12, wherein the one or more conditions comprise the flow direction of the fluid at the distal region of the aspiration catheter during operation of the clot removal state indicating fluid flow in a distal direction.
Clause 14. A thrombectomy system, comprising: an aspiration catheter configured for advancement through vasculature of a subject to facilitate clot removal from the vasculature of the subject; a fluid jet proximate to a distal end of the aspiration catheter; and a flow sensor positioned on the aspiration catheter proximal to the fluid jet, wherein the flow sensor is configured to detect a flow rate of fluid within an aspiration lumen of the aspiration catheter during operation of a clot removal state of the thrombectomy system, wherein the flow rate of the fluid within the aspiration lumen indicates a clog state of the aspiration catheter.
Clause 15. The thrombectomy system of clause 14, wherein the flow sensor comprises an ultrasonic flow meter that includes a plurality of ultrasonic transducers.
Clause 16. The thrombectomy system of clause 14, wherein the flow sensor comprises an electromagnetic flow meter that includes a plurality of coils and a plurality of electrodes.
Clause 17. The thrombectomy system of clause 14, wherein the flow sensor comprises a vortex shedding flow meter that includes a bluff body and one or more pressure sensors.
Clause 18. The thrombectomy system of clause 14, wherein the flow sensor comprises a thermal flow meter that includes a plurality of temperature sensors.
Clause 19. The thrombectomy system of clause 14, wherein the flow sensor comprises a differential pressure flow meter that includes a restrictive element.
Clause 20. The thrombectomy system of clause 14, wherein the thrombectomy system is configured to present an alert on a user interface associated with the thrombectomy system after determining that the flow rate of the fluid within the aspiration lumen of the aspiration catheter during operation of the clot removal state satisfies one or more conditions.
Clause 21. The thrombectomy system of clause 20, wherein the alert comprises a directive to deactivate the clot removal state of the thrombectomy system.
Clause 22. The thrombectomy system of clause 20, wherein the alert comprises an indication of clogging of the aspiration catheter.
Clause 23. The thrombectomy system of clause 20, wherein the one or more conditions comprise the flow rate of the fluid within the aspiration lumen of the aspiration catheter during operation of the clot removal state being above a threshold flow rate.
Clause 24. The thrombectomy system of clause 14, wherein the thrombectomy system is configured to selectively deactivate the clot removal state after determining that the flow rate of the fluid within the aspiration lumen of the aspiration catheter during operation of the clot removal state satisfies one or more conditions.
Clause 25. The thrombectomy system of clause 24, wherein the one or more conditions comprise the flow rate of the fluid within the aspiration lumen of the aspiration catheter during operation of the clot removal state being above a threshold flow rate.
The principles disclosed herein may be implemented in various formats. For example, at least some techniques discussed herein may be performed as a method that includes various acts for achieving particular results or benefits. In some instances, the techniques discussed herein are represented in computer-executable instructions that may be stored on one or more hardware storage devices. The computer-executable instructions may be executable by one or more processors to carry out (or to configure a system to carry out) the disclosed techniques. In some embodiments, a system may be configured to send the computer-executable instructions to a remote device to configure the remote device for carrying out the disclosed techniques.
Systems for implementing the disclosed embodiments may include various components, such as, by way of non-limiting example, processor(s), storage, sensor(s), I/O system(s), communication system(s), etc.
The processor(s) may comprise one or more sets of electronic circuitries that include any number of logic units, registers, and/or control units to facilitate the execution of computer-readable instructions (e.g., instructions that form a computer program). Such computer-readable instructions may be stored within storage. The storage may comprise physical system memory and may be volatile, non-volatile, or some combination thereof. Furthermore, storage may comprise local storage, remote storage (e.g., accessible via communication system(s) or otherwise), or some combination thereof.
In some implementations, the processor(s) may comprise or be configurable to execute any combination of software and/or hardware components that are operable to facilitate processing using machine learning models or other artificial intelligence-based structures/architectures. Artificial intelligence-based structures/architectures may take on any suitable form, such as by comprising or utilizing hardware components and/or computer-executable instructions operable to carry out function blocks and/or processing layers configured in the form of, by way of non-limiting example, single-layer neural networks, feed forward neural networks, radial basis function networks, deep feed-forward networks, recurrent neural networks, long-short term memory (LSTM) networks, gated recurrent units, autoencoder neural networks, variational autoencoders, denoising autoencoders, sparse autoencoders, Markov chains, Hopfield neural networks, Boltzmann machine networks, restricted Boltzmann machine networks, deep belief networks, deep convolutional networks (or convolutional neural networks), deconvolutional neural networks, deep convolutional inverse graphics networks, generative adversarial networks, liquid state machines, extreme learning machines, echo state networks, deep residual networks, Kohonen networks, support vector machines, neural Turing machines, and/or others.
In some instances, actions performable by a system may rely at least in part on communication system(s) for receiving information from remote system(s), which may include, for example, separate systems or computing devices, sensors, and/or others. The communications system(s) may comprise any combination of software or hardware components that are operable to facilitate communication between on-system components/devices and/or with off-system components/devices. For example, the communications system(s) may comprise ports, buses, or other physical connection apparatuses for communicating with other devices/components. Additionally, or alternatively, the communications system(s) may comprise systems/components operable to communicate wirelessly with external systems and/or devices through any suitable communication channel(s), such as, by way of non-limiting example, Bluetooth, ultra-wideband, WLAN, infrared communication, and/or others.
A system may comprise or be in communication with sensor(s). Sensor(s) may comprise any device for capturing or measuring data representative of perceivable phenomenon. By way of non-limiting example, the sensor(s) may comprise one or more image sensors, microphones, thermometers, barometers, magnetometers, accelerometers, gyroscopes, and/or others.
Furthermore, a system may comprise or be in communication with I/O system(s). I/O system(s) may include any type of input or output device such as, by way of non-limiting example, a touch screen, a mouse, a keyboard, a controller, and/or others, without limitation. For example, the 1/O system(s) may include a display system that may comprise any number of display panels, optics, laser scanning display assemblies, and/or other components. One will appreciate, in view of the present disclosure, that the sensor(s) may, in some instances, be utilized as I/O system(s).
Disclosed embodiments may comprise or utilize a special purpose or general-purpose computer including computer hardware, as discussed in greater detail below. Disclosed embodiments also include physical and other computer-readable media for carrying or storing computer-executable instructions and/or data structures. Such computer-readable media can be any available media that can be accessed by a general-purpose or special-purpose computer system. Computer-readable media that store computer-executable instructions in the form of data are one or more “computer-readable recording media,” “physical computer storage media,” or “hardware storage device(s).” Computer-readable media that merely carry computer-executable instructions without storing the computer-executable instructions are “transmission media.” Thus, by way of example and not limitation, the current embodiments can comprise at least two distinctly different kinds of computer-readable media: computer storage media and transmission media.
Computer storage media (aka “hardware storage device”) are computer-readable hardware storage devices, such as RAM, ROM, EEPROM, CD-ROM, solid state drives (“SSD”) that are based on RAM, Flash memory, phase-change memory (“PCM”), or other types of memory, or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store desired program code means in hardware in the form of computer-executable instructions, data, or data structures and that can be accessed by a general-purpose or special-purpose computer.
A “network” may comprise one or more data links that enable the transport of electronic data between computer systems and/or modules and/or other electronic devices. When information is transferred or provided over a network or another communications connection (either hardwired, wireless, or a combination of hardwired or wireless) to a computer, the computer properly views the connection as a transmission medium. Transmission media can include a network and/or data links which can be used to carry program code in the form of computer-executable instructions or data structures and which can be accessed by a general purpose or special purpose computer. Combinations of the above are also included within the scope of computer-readable media.
Further, upon reaching various computer system components, program code means in the form of computer-executable instructions or data structures can be transferred automatically from transmission computer-readable media to physical computer-readable storage media (or vice versa). For example, computer-executable instructions or data structures received over a network or data link can be buffered in RAM within a network interface module (e.g., a “NIC”), and then eventually transferred to computer system RAM and/or to less volatile computer-readable physical storage media at a computer system. Thus, computer-readable physical storage media can be included in computer system components that also (or even primarily) utilize transmission media.
Computer-executable instructions comprise, for example, instructions and data which cause a general-purpose computer, special purpose computer, or special purpose processing device to perform a certain function or group of functions. The computer-executable instructions may be, for example, binaries, intermediate format instructions such as assembly language, or even source code. Although the subject matter has been described in language specific to structural features and/or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the described features or acts described above. Rather, the described features and acts are disclosed as example forms of implementing the claims.
Disclosed embodiments may comprise or utilize cloud computing. A cloud model can be composed of various characteristics (e.g., on-demand self-service, broad network access, resource pooling, rapid elasticity, measured service, etc.), service models (e.g., Software as a Service (“SaaS”), Platform as a Service (“PaaS”), Infrastructure as a Service (“IaaS”), and deployment models (e.g., private cloud, community cloud, public cloud, hybrid cloud, etc.).
Those skilled in the art will appreciate that the invention may be practiced in network computing environments with many types of computer system configurations, including, personal computers, desktop computers, laptop computers, message processors, hand-held devices, multi-processor systems, microprocessor-based or programmable consumer electronics, network PCs, minicomputers, mainframe computers, mobile telephones, PDAs, pagers, routers, switches, wearable devices, and the like. The invention may also be practiced in distributed system environments where multiple computer systems (e.g., local and remote systems), which are linked through a network (either by hardwired data links, wireless data links, or by a combination of hardwired and wireless data links), perform tasks. In a distributed system environment, program modules may be located in local and/or remote memory storage devices.
Alternatively, or in addition, the functionality described herein can be performed, at least in part, by one or more hardware logic components. For example, and without limitation, illustrative types of hardware logic components that can be used include Field-programmable Gate Arrays (FPGAs), Program-specific Integrated Circuits (ASICs), Application-specific Standard Products (ASSPs), System-on-a-chip systems (SOCs), Complex Programmable Logic Devices (CPLDs), central processing units (CPUs), graphics processing units (GPUs), and/or others.
As used herein, the terms “executable module,” “executable component,” “component,” “module,” or “engine” can refer to hardware processing units or to software objects, routines, or methods that may be executed on one or more computer systems. The different components, modules, engines, and services described herein may be implemented as objects or processors that execute on one or more computer systems (e.g., as separate threads).
It is contemplated that various combinations or sub-combinations of the specific features and aspects of the embodiments disclosed above may be made and still fall within one or more of the embodiments. Further, the disclosure herein of any particular feature, aspect, method, property, characteristic, quality, attribute, element, or the like in connection with an embodiment can be used in all other embodiments set forth herein. Accordingly, it should be understood that various features and aspects of the disclosed embodiments can be combined with or substituted for one another in order to form varying modes of the disclosed embodiments. Thus, it is intended that the scope of the present disclosure herein disclosed should not be limited by the particular disclosed embodiments described above. Moreover, while the present disclosure is susceptible to various modifications, and alternative forms, specific examples thereof have been shown in the drawings and are herein described in detail. It should be understood, however, that the present disclosure is not to be limited to the particular forms or methods disclosed, but to the contrary, the present disclosure is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the various embodiments described and the appended claims.
The ranges disclosed herein also encompass any and all overlap, sub-ranges, and combinations thereof. Language such as “up to,” “at least,” “greater than,” “less than,” “between,” and the like includes the number recited. Numbers preceded by a term such as “approximately”, “about”, and “substantially” as used herein include the recited numbers (e.g., about 10%=10%), and also represent an amount close to the stated amount that still performs a desired function or achieves a desired result. For example, the terms “approximately”, “about”, and “substantially” may refer to an amount that is within less than 10% of, within less than 5% of, within less than 1% of, within less than 0.1% of, and within less than 0.01% of the stated amount.
For purposes of the present disclosure and appended claims, the conjunction “or” is to be construed inclusively (e.g., “an apple or an orange” would be interpreted as “an apple, or an orange, or both”; e.g., “an apple, an orange, or an avocado” would be interpreted as “an apple, or an orange, or an avocado, or any two, or all three”), unless: (i) it is explicitly stated otherwise, e.g., by use of “either . . . or,” “only one of,” or similar language; or (ii) two or more of the listed alternatives are mutually exclusive within the particular context, in which case “or” would encompass only those combinations involving non-mutually-exclusive alternatives. For purposes of the present disclosure and appended claims, the words “comprising,” “including,” “having,” and variants thereof, wherever they appear, shall be construed as open-ended terminology, with the same meaning as if the phrase “at least” were appended after each instance thereof.
This application claims priority to U.S. Provisional Patent Application No. 63/610,247, filed on Dec. 14, 2023, and entitled “CATHETER CLOG DETECTION IN THROMBECTOMY DEVICES”, the entirety of which is incorporated herein by reference for all purposes.
| Number | Date | Country | |
|---|---|---|---|
| 63610247 | Dec 2023 | US |
