Patent Application
20240307065
This disclosure relates generally to medical devices, and more particularly, to apparatuses and methods for treating tissue by applying force by a loop member. Described herein are systems and methods for the deployment and engagement of endoscopic loop systems.
There are various instances in which it may become necessary or desirable to deliver a deployable snare into engagement with tissue. For example, such a snare may be used to induce hemostasis during a polypectomy, esophageal variceal bleeding, gastric variceal bleeding, or the excision of gastrointestinal stromal tumors. Further, deployable snares may be useful in ligation of varices or polyps, closure of gastrointestinal fistulas, and other procedures.
There are various commercially available deployable snares. Some deployable snares comprise a loop made of nylon, one or more elongated wires, sutures and/or other materials. The size and configuration of the loop may be adjusted using a stopper or cinching member that may be sized to surround first and second ends of the loop. As the stopper or cinching member is distally advanced relative to the loop, the size of the loop may be decreased, and a desired amount of force may be imposed upon target tissue. However, some commercially available applicators offer low control for placing a loop. The loops may deflect out of the intended plane of application and may be difficult to accurately control during placement.
The present embodiments provide apparatus and methods for treating tissue by applying a force to the tissue.
In one embodiment, the apparatus comprises a deployable segment having a loop member formed at a distal region of the deployable segment. A frame is operatively coupled to the loop member. In any one of the preceding embodiments, the frame is coupled to at least three lugs. In any one of the preceding embodiments, each lug has a slit, and the loop member extends through each lug slit. The loop member includes a gauge diameter, the slit defines an opening, and the slit opening may be narrower than the loop member gauge diameter.
In any one of the preceding embodiments, the at least three lugs each include an aperture, and the frame extends through each lug aperture. In embodiments where the at least three lugs includes a first lug, a second lug, and a third lug, the first lug may be spaced apart from the second lug, and the second lug may be spaced apart from the third lug. Each of the at least three lugs further may comprise a first end and a second end, with a taper at the first end.
In any one of the preceding embodiments, the apparatus further includes a cannula with a lumen extending therethrough. The cannula is dimensioned to circumferentially surround at least a portion of the deployable segment and at least a portion of the frame.
In any one of the preceding embodiments, the frame has proximal and distal regions and a bend relative to a first longitudinal axis of the proximal region of the deployable segment. The distal region of the frame is collapsible, and the frame comprises a loop shape. The frame bend may be at an angle within a range of about 0 degrees to about 90 degrees. The frame bend is disposed proximal to the one or more lugs.
The present disclosure also provides methods of treating tissue by applying a force to the tissue. In one embodiment, a method includes expanding the frame, retracting the loop member, and deploying the deployable segment.
Other systems, methods, features, and advantages of the invention will be, or will become, apparent to one with skill in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, methods, features, and advantages be within the scope of the invention and be encompassed by the following claims.
The invention can be better understood with reference to the following drawings and description. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention. Moreover, in the figures, like referenced numerals designate corresponding parts throughout the different views.
The illustrated embodiments are merely examples and are not intended to limit the disclosure. The schematics are drawn to illustrate features and concepts and are not necessarily drawn to scale.
The foregoing is a summary, and thus, necessarily limited in detail. The above-mentioned aspects, as well as other aspects, features, and advantages of the present technology will now be described in connection with various embodiments. The inclusion of the following embodiments is not intended to limit the disclosure to these embodiments, but rather to enable any person skilled in the art to make and use the contemplated invention(s). Other embodiments may be utilized, and modifications may be made without departing from the spirit or scope of the subject matter presented herein. Aspects of the disclosure, as described and illustrated herein, can be arranged, combined, modified, and designed in a variety of different formulations, all of which are explicitly contemplated and form part of this disclosure.
In the present application, the term “proximal” refers to a direction that is generally towards a physician during a medical procedure, while the term “distal” refers to a direction that is generally towards a target site within a patient's anatomy during a medical procedure. Referring to
For illustrative purposes, one example of a deployable segment 8 is shown in
The loop member 18 may be made of various suitable materials, with or without a coating. For example, the loop member 18 may include nylon monofilament. Alternatively, the loop member 18 may be made of a non-conductive material, such as polypropylene or another plastic. The loop member 18 may also include a wound cable, coated cable, or braided fibers. The loop member 18 may include a single material or multiple materials. In embodiments where the outer surface of the loop member 18 has an increased resistance to slip, such as a woven material, the slip resistance provides increased control during contact with patient tissue. In addition to being formed of a solid cord, the loop member 18 may be a hollow tube or spring, covered or uncovered.
In some embodiments, the loop member 18 includes a stretchy material, for example and without limitation, elastic, silicone, latex, neoprene, or other materials. A loop member 18 with stretchy properties may be used to provide a compressive effect to target tissue after placement of a deployable segment 8 within a patient.
Referring back to
The frame 20 may additionally include a steering portion that extends proximally from the loop-shaped portion of the frame 20, and this steering portion may be integral or otherwise connected to the loop-shaped portion of the frame 20. The steering portion is engageable by a physician to help orient the frame 20 during positioning and/or deployment of the loop member 18 relative to tissue, as explained further below.
The loop-shaped portion of the frame 20 may comprise a shape-memory material, such as nitinol, or another suitable material capable of deploying to a predetermined shape. Such material of the frame 20 may allow the frame 20 to deflect or bend temporarily during use without bending permanently. The frame 20 wire may comprise a flat wire or a round wire, and in some embodiments may include multiple adjacent or overlapping wires forming the frame 20.
In some embodiments, the diameter of the frame 20 may be approximately equal to the gauge diameter of the loop member 18, when the loop member 18 is held in an open state by the frame 20, as explained further below. In some instances, such as depicted in
Referring still to
In some embodiments, the cannula 30 is more flexible at a distal portion 33 of the cannula 30 than at a proximal portion 31 of the cannula. In some embodiments, 10% to 40% of the cannula is made of or comprises a more flexible material and 60% to 90% of the cannula is made of or comprises a stiffer material. Increased flexibility of the cannula 30 at the distal end 33 facilitates bending of the cannula 30 within an endoscope which may increase ease and predictability of movement of the cannula 30 during insertion and retraction.
In some embodiments, the distal region of the frame 20 is collapsible. The cannula 30 may be slid distally, along arrow 37, over the frame 20, for example during insertion or retraction of the system 2, thereby collapsing the frame 20. Distal sliding, along arrow 37, of the cannula 30 also collapses the loop member 18. Proximal sliding, along arrow 35, of the cannula 30, thereby exposing the frame 20 and/or loop member 18, may allow the frame 20 and loop member 18 to return to a predefined or predisposed shape.
In some embodiments, as best seen in
In such embodiments, the lug 22 may be formed with first side 27a and second side 27b that bound the slit 24. The first and second sides 27a and 27b may taper inward at ends 29a and 29b, respectively, as shown in
In some embodiments, the loop member 18 is snappable into the slit 24 of the lug 22, where it will be held during the delivery and pre-deployment state. The loop member 18 comprises a gauge diameter 48, and the opening at the second region 26 of the slit 24 is narrower than the loop member 18 gauge diameter 48. The loop member 18 is retained with the slit 24 such that the loop member 18 cannot pass through the slit opening 26 when external forces are not significantly applied to the loop member 18. More specifically, in the absence of significant external forces, the inherent properties of the first and second sides 27a and 27b of the lug 22, coupled with the size of the opening 26, are sufficient to retain the loop member 18 within the first region 25 of the lug 22 before desired deployment. However, the loop member 18 may be released from the lug 22 when an external force is applied that is sufficient to overcome the counteractive forces applied by the first and second sides 27a and 27b of the lug 22. Either the frame 20 and lug 22 may be held steady while the loop member 18 is moved, or vice versa, thereby causing the loop member 18 to move relative to the frame 20 and the lug 22, causing disengagement of the loop member 18 from the lug 22 upon such external force. For example, once the loop member 18 is cinched and secured to the target, the frame 20 is pulled away to decouple the loop member 18 from the lugs 22. In many instances, the act of cinching will release one (or more) lugs 22 as the loop member 18 is reduced.
In one embodiment, the frame 20 may be stiffer than the loop member 18, either due to material properties and/or increased thickness of materials associated with the frame 20. In this manner, the frame 20 may be more inclined to hold its shape when any external forces are applied that cause the loop member 18 to be reduced and detached from the lug 22.
The lug 22 comprises a suitable material, by way of example and without limitation, such as polycarbonate, and may be externally secured to the frame 20 or integrally formed with the frame 20. In the example depicted in
In one embodiment, the system 2 includes at least three lugs 22a, 22b, 22c. Each lug 22a, 22b, 22c may comprise a slit 24, such as the slit 24 explained with respect to
In one embodiment, the at least three lugs 22a, 22b, 22c are spaced apart substantially circumferentially along the frame 20 so that the first lug 22a is at least 15 degrees from the second lug 22b, and the second lug 22b is at least 15 degrees from the third lug 22c, thereby allowing a sufficient gap in-between selective lugs 22 to allow only periodic coupling of the loop member 18 to the frame 20. Advantageously, the selectively spaced-apart coupling locations may facilitate release of the loop member 18 from the frame 20 when an external force is applied, as opposed to a single elongated lug 22 which may require a higher force to release the loop member 18.
In other embodiments, the spacing in-between adjacent lugs 22 may be higher, such as about 30 degrees to about 90 degrees, greater than about 30 degrees, greater than about 45 degrees, greater than about 60 degrees, greater than about 75 degrees, greater than about 90 degrees, or more. Variation in the spacing may be tailored to a specifically desired release force for the loop member 18, e.g., more closely spaced lugs 22 may require a higher withdrawal force, whereas further spaced apart lugs 22 may require a lesser force applied.
In other embodiments, a fourth lug 22d may be provided, wherein each lug 22 is spaced apart from each of the other lugs 22. In this example, the at least four lugs 22a, 22b, 22c, 22d may be spaced apart substantially circumferentially along the frame 20 so that the first lug 22a is about 90 degrees from the second lug 22b, the second lug 22b is about 90 degrees from the third lug 22c, and the third lug 22c is about 90 degrees from the fourth lug 22d. However, as noted above, other lug 22 spacings may be used depending on the withdrawal force desired to release the loop member 18 from the frame 20.
In other embodiments, the frame 20 may be formed as one extrusion of the lug 22 cross-section, with or without the aperture 28. In this way, the loop member 18 is secured within the first region 25 and when under the proper withdrawal force, deployed via the formed outlet of the second region 26. These embodiments incorporate the functionality of the previously described lugs 22 within the structure of the frame 20, eliminating the need for lugs 22. In some embodiments, in which the aperture 28 is included in the extruded cross-section; wires, cords, cables and/or braided line can be inserted to incorporate desired mechanical properties. These mechanical properties may include but are not limited to; increased tension capabilities and/or shape memory capabilities.
Referring to
The frame 20 may be inclined to assume a state that is either on the same plane as the cannula 30 or angled relative to the cannula 30. In the example of
Alternatively, as shown in
The frame bend 40 depicted in
In some embodiments, such as shown in
A tip 50 may be coupled to the distal region of the frame 20. The tip 50 may be an atraumatic nose cone, and optionally, there may be a taper 38 at the distal end of the tip 50. The tip 50 may be attached to the frame 20 or integrally formed. For example, the tip 50 may be attached to the frame 20 using an adhesive. In some embodiments, the tip 50 includes a groove that contributes to attachment of the tip 50 to the frame 20. The tip 50 may also include a recess for the loop member 18, so that the recess provides clearance to accept at least a portion of the loop member 18 when the loop member 18 is collapsed and/or within a cannula 30. A diameter of the tip 50, or a diameter of a portion of the tip 50, may be less than the inner diameter of a cannula lumen 32.
In one exemplary method, the system 2 may be delivered to a target site within a patient's anatomy while the frame 20 and the loop member 18 are held in a delivery state within the cannula 30, more specifically, in the distal portion 33. The tip 50 facilitates atraumatic placement of the system 2 at a target site. As noted above, in some embodiments, the system 2 may be delivered via an endoscope, where the cannula 30 extends through a working channel of the endoscope.
The method further includes expanding the frame 20. Expanding the frame 20 may include extending the frame 20 from the cannula 30 in a distal direction 37 or retracting the cannula 30 in a proximal direction 35, thereby exposing the frame 20 and allowing it to assume its predefined shape, e.g., as shown in
At this time, the loop member 18 is held in an open state since the loop member 18 is coupled to the one or more lugs 22 of the frame 20. As noted above, advantageously, the frame 20 contributes to the practitioner's ability to control insertion, placement, and deployment of the loop member 18. Further, the predefined bend 40 of the frame 20 may facilitate orientation of the loop member 18 relative to tissue. At this stage, a physician may place the loop member 18 over tissue, or otherwise engage or treat the tissue.
In embodiments in which the deployable segment 8 is detachable from the delivery segment 10, the practitioner may deploy the deployable segment 8 within the patient and remove the remainder of the system 2 from the patient. For example, segment 8 may be coupled to delivery system 10 by a flexible member that runs from an actuator in the handle and terminates with a distal hook or loop. This method may include retracting the loop member 18, wherein retracting the loop member 18 involves decoupling the loop member 18 from the one or more lugs 22 of the frame 20. In some embodiments, such as shown in
Handle 52 is coupled to the distal frame and loop assembly via a shaft composed of a few members (i.e., “nested” tubes & an inner control wire with distal hook). After cinching the loop, the hook is extended to expose the proximal end of the loop 12 from the inner lumen, which will free it from the confines of the lumen and allow it to be pulled free from the hook.
In some embodiments, loading button 13 is depressed to extend the hook for loading the loop onto the hook. And outer sheath hub 17 is used to retract outer sheath 15 to expose the loop assembly.
While various embodiments of the invention have been described, the invention is not to be restricted except in light of the attached claims and their equivalents. Moreover, the advantages described herein are not necessarily the only advantages of the invention and it is not necessarily expected that every embodiment of the invention will achieve all of the advantages described.
The term “about” or “approximately,” when used before a numerical designation or range (e.g., to define a length or pressure), indicates approximations which may vary by (+) or (−) 5%, 1% or 0.1%. All numerical ranges provided herein are inclusive of the stated start and end numbers. The term “substantially” indicates mostly (i.e., greater than 50%) or essentially all of a device, substance, or composition.
As used in the description and claims, the singular form “a”, “an” and “the” include both singular and plural references unless the context clearly dictates otherwise. For example, the term “lug” may include, and is contemplated to include, a plurality of lugs. At times, the claims and disclosure may include terms such as “a plurality,” “one or more,” or “at least one;” however, the absence of such terms is not intended to mean, and should not be interpreted to mean, that a plurality is not conceived.
As used herein, the term “comprising” or “comprises” is intended to mean that the devices, systems, and methods include the recited elements, and may additionally include any other elements. “Consisting essentially of” shall mean that the devices, systems, and methods include the recited elements and exclude other elements of essential significance to the combination for the stated purpose. Thus, a system or method consisting essentially of the elements as defined herein would not exclude other materials, features, or steps that do not materially affect the basic and novel characteristic(s) of the claimed disclosure. “Consisting of” shall mean that the devices, systems, and methods include the recited elements and exclude anything more than a trivial or inconsequential element or step. Embodiments defined by each of these transitional terms are within the scope of this disclosure.
The examples and illustrations included herein show, by way of illustration and not of limitation, specific embodiments in which the subject matter may be practiced. Other embodiments may be utilized and derived therefrom, such that structural and logical substitutions and changes may be made without departing from the scope of this disclosure. Such embodiments of the inventive subject matter may be referred to herein individually or collectively by the term “invention” merely for convenience and without intending to voluntarily limit the scope of this application to any single invention or inventive concept, if more than one is in fact disclosed. Thus, although specific embodiments have been illustrated and described herein, any arrangement calculated to achieve the same purpose may be substituted for the specific embodiments shown. This disclosure is intended to cover any and all adaptations or variations of various embodiments. Combinations of the above embodiments, and other embodiments not specifically described herein, will be apparent to those of skill in the art upon reviewing the above description.
This application claims the priority benefit of U.S. Provisional Patent Application Ser. No. 63/229,717, filed Aug. 5, 2021, the contents of which are herein incorporated by reference in their entirety.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US2022/039483 | 8/4/2022 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 63229717 | Aug 2021 | US |
