Urethral treatment device and method

Abstract

To provide a device and method for treating tissue. **Solution**: A device (20) for treating a stenosed urethra (90) is provided. A delivery tool (30) is advanced to a location within a region (92) of the urethra to be treated. The distal portion (34) of the delivery tool includes an expandable element (50) that expands within the urethra, an implant (70) disposed outside the outer surface of the expandable element, and a cutting electrode (60) releasably coupled to the outer surface of the implant and configured to pass an electric current through the tissue of the urethra to form an implant-receiving incision in the tissue surrounding the lumen of the urethra by application of the electric current. The cutting electrode is shaped to conform to the shape of the implant such that the implant-receiving incision is formed in the shape of the implant substantially without movement of the cutting electrode, e.g., without rotation. Other uses are also described.

Description

Technical Field

[0001] (Cross - Reference to Related Applications) This application claims the benefit of priority of U.S. Provisional Patent Application No. 63 / 357,122, filed Jun. 30, 2022, and U.S. Provisional Patent Application No. 63 / 430,030, filed Dec. 04, 2022, both by Hizkiyahu et al., and titled "URETHRAL TREATMENT APPARATUS AND METHOD", and both applications are incorporated herein by reference in their entireties.

[0002] Some applications of the present invention generally relate to devices and methods for treating tissue. More specifically, some applications of the present invention relate to devices and methods for treating benign prostatic hyperplasia (BPH).

Background Art

[0003] Benign prostatic hyperplasia (BPH), also known as prostate enlargement, is a condition commonly seen in men as they age. BPH is a non - cancerous condition in which the prostate gland enlarges to the point of narrowing the urethra, obstructing urine flow, causing difficult and painful urination, and in extreme cases, complete inability to urinate.

Summary of the Invention

[0004] In some applications of the present invention, devices and methods are provided for treating a narrowed body cavity, such as the urethra narrowed by benign prostatic hyperplasia (BPH). Typically, the device comprises a delivery tool having a proximal portion and a distal portion. The distal portion of the delivery tool is configured to be advanced to a location within the region of the urethra that is the treatment target due to prostate enlargement and the accompanying narrowing of the region. In some applications, the distal portion includes an operating head having an expandable element, an implant, and a cutting electrode. The expandable element, such as an inflatable balloon, is expanded within the urethra to widen the urethra and expand the narrowed region. The cutting electrode is typically releasably coupled to the implant and forms an incision in the inner surface of the urethra after the expandable element has been expanded within the urethra. The cutting electrode is typically shaped to conform to the shape of the implant (usually disposed outside the implant) so as to form an implant receiving incision in the shape of the implant, substantially without movement of the cutting electrode, e.g., without rotation. After the cutting electrode has formed an incision in the urethra, the implant is released into the incision in the urethra and embedded in the prostate tissue surrounding the incision in the urethra to maintain the urethra in an expanded state.

[0005] Accordingly, in some applications of the present invention, an apparatus for treating a urethra with a narrowed lumen, comprising a delivery tool having a proximal portion and a distal portion, the distal portion being configured to be advanced to a location within the region of the urethra that is the treatment target, an expandable element configured to be expanded within the urethra to widen the urethra within the region that is the treatment target, the expandable element defining an outer surface, an implant disposed outside the outer surface of the expandable element, a cutting electrode releasably coupled to the outer surface of the implant and configured to pass an electric current through the tissue of the urethra to form an implant receiving incision in the tissue surrounding the lumen of the urethra by application of the electric current, and a delivery tool including the same, A cutting electrode is provided that is shaped to conform to the shape of an implant so as to form an implant receiving notch in the shape of the implant, substantially without movement of the cutting electrode.

[0006] In some applications, the cutting electrode is shaped to conform to the shape of the implant such that the implant receiving notch is formed in the shape of the implant, substantially without rotation of the cutting electrode.

[0007] In some applications, the cutting electrode is configured to be withdrawn from the urethra after forming the implant receiving notch.

[0008] In some applications, the cutting electrode has a distal portion releasably coupled to the implant and a proximal extension disposed on a delivery tool, and the cutting electrode is configured to be withdrawn from the urethra by pulling the proximal extension of the electrode in a proximal direction.

[0009] In some applications, the implant is configured as a C-shaped open ring.

[0010] In some applications, the implant is configured to be wrapped around an expandable element while the distal portion of the delivery tool is advanced to a location within the region of the urethra to be treated.

[0011] In some applications, the thickness of the implant is from 0.01 to 1 mm.

[0012] In some applications, the width of the implant is from 0.5 to 4 mm.

[0013] In some applications, the cutting electrode is formed of nitinol.

[0014] In some applications, the implant is electrically insulated from the cutting electrode.

[0015] In some applications, the implant is configured to maintain the urethra in an expanded state within the incision area by being deployed within the incision.

[0016] In some applications, the device further comprises an imaging device disposed on the delivery tool and is configured to provide visualization of the area of the urethra to be treated by the imaging device.

[0017] In some applications, the expandable element includes an inflatable balloon.

[0018] In some applications, the inflatable balloon is transparent.

[0019] In some applications, the device further comprises an imaging device disposed on the delivery tool, and the inflatable balloon is configured to provide visualization of the area of the urethra to be treated by the imaging device through the inflatable balloon.

[0020] In some applications, the device further comprises one or more sutures configured to releasably couple the cutting electrode to the implant prior to application of current by the cutting electrode.

[0021] In some applications, the one or more sutures are configured to separate from the implant upon application of current, thereby releasing the cutting electrode from the implant.

[0022] In some applications, the cutting electrode comprises coiled tips at each end thereof, and each coiled tip prevents one of the sutures, where the end of the cutting electrode is disposed closest to the end of the implant, from passing therethrough, thereby holding each end of the cutting electrode in place relative to the implant, and when the cutting electrode is pulled proximally, the coiled tip is configured to straighten and pass through the one or more sutures.

[0023] In some applications, the device further comprises a single implant carrier arm extending from the axis of the delivery tool and disposed outside the outer surface of the expandable element, and the implant carrier is configured to release the implant into the implant receiving notch after the cutting electrode has formed the implant receiving notch.

[0024] In some applications, the implant carrier arm is coated with an electrically insulating coating.

[0025] In some applications, the device further comprises an electrically non-conductive implant holder coupled to the implant carrier arm, and the implant is configured to be disposed between the implant carrier arm and the implant holder such that the implant is held in place by the implant carrier arm and the implant holder, and the implant holder is configured to be retracted proximally relative to the implant carrier arm such that the implant is released into the implant receiving notch by the implant carrier arm.

[0026] In some applications, the device further comprises at least one radial arm having a length sufficient to apply pressure to the wall of the urethra to expand the urethra in a region proximate to the expandable element when the expandable element is in an expandable state and insufficient to contact the implant.

[0027] According to some applications of the present invention, a method for treating a urethra having a lumen stenosed by benign prostatic hyperplasia (BPH), comprising: identifying a stenotic region of the urethra to be treated; inserting a delivery tool into the urethra, the delivery tool comprising: an expandable element defining an outer surface; an implant disposed on the outer surface of the expandable element; a cutting electrode releasably coupled to the outer surface of the implant, inserting the delivery tool into the urethra; Using a delivery tool to deliver an expandable element to a specified stenotic region of the urethra, and Expanding the urethra by expanding the expandable element in the specified stenotic region of the urethra, and Thereafter, passing an electric current through the tissue using a cutting electrode to form an implant-receiving incision in the tissue surrounding the lumen of the urethra, wherein the cutting electrode is shaped to conform to the shape of the implant so as to form the implant-receiving incision in the shape of the implant without substantially moving the cutting electrode, forming the implant-receiving incision, and Releasing the implant into the incision to maintain the urethra in an expanded state, further providing a method comprising.

[0028] In some applications, the method further comprises withdrawing the cutting electrode from the urethra after forming the implant-receiving incision.

[0029] In some applications, the cutting electrode is shaped to conform to the shape of the implant so as to form the implant-receiving incision in the shape of the implant without substantially rotating the cutting electrode.

[0030] In some applications, before passing an electric current through the tissue using the cutting electrode, the cutting electrode is coupled to the implant via one or more sutures, and passing an electric current through the tissue using the cutting electrode comprises releasing the cutting electrode from the implant by separating the suture from the implant.

[0031] In some applications, the method further comprises using a radial arm to apply pressure to the wall of the urethra in a region adjacent to the expandable element to maintain the region of the urethra adjacent to the expandable element in an expanded state.

[0032] The present invention will be more fully understood from the following detailed description of the embodiments in conjunction with the drawings.

Brief Description of the Drawings

[0033]

Fig. 1A-1B

Fig. 2A-2C

Fig. 3A-3F

Fig. 4

Fig. 5A-5B

Fig. 6A-6B

Fig. 7A-7B

Fig. 8-9

[0034] Some uses of the present invention relate to devices and methods for the treatment of body cavities, and more specifically, to devices and methods for expanding and / or assisting in and / or maintaining the expansion of a body cavity, such as the urethra, to relieve occlusion of the body cavity, but are not limited thereto.

[0035] Reference is now made to FIGS. 1A and 1B, which are schematic views showing an overview of an apparatus 20 for the treatment of a urethra narrowed by benign prostatic hyperplasia (BPH) according to some uses of the present invention.

[0036] In some uses, the apparatus 20 comprises a delivery tool 30, such as an endoluminal catheter. The delivery tool 30 typically comprises a proximal portion 32, a distal portion 34, and an elongate shaft 36 disposed between the proximal portion 32 and the distal portion 34. The distal portion 34 is configured to advance distally within the urethra to a location within the region of the urethra that is narrowed and thus in need of treatment. Typically, the distal portion 34 is shaped to define a blunt, non-traumatic tip portion 35, as shown in FIGS. 1A to 1B. It should be noted that the terms "distal" and related terms, when used with respect to a device or a portion thereof, should be construed to mean the end of the device or the portion thereof that is normally further away from the location where the device is inserted into the patient's body when the device is inserted into the patient's body. The terms "proximal" and related terms, when used with respect to a device or a portion thereof, should be construed to mean the end of the device or the portion thereof that is normally closer to the location where the device is inserted into the patient's body when the device is inserted into the patient's body.

[0037] In some uses, the apparatus 20 comprises a handle 22 configured to be held by a user, such as a surgeon. In some uses, the handle 22 is connected to a power source (not shown) via a cable 24. Additionally or alternatively, the handle 22 comprises a power source contained therein. Typically, the handle 22 includes a manually operable lever and actuation mechanism. As shown, the elongate shaft 36 is typically coupled to the handle 22. In some uses, the apparatus 20 comprises an inlet and / or outlet 28 configured to allow the insertion and removal of fluids, such as air, water, and / or saline, into and from the apparatus 20.

[0038] Typically, device 20 further includes an operating head 40 shown in an extended configuration, for example, as shown in FIG. 1B. The operating head 40 is typically advanced distally in a radially collapsed state in delivery tool 30 and radially expanded within the urethra in the region to be treated, as will be described in more detail below with reference to FIGS. 2A through 2C and FIGS. 3A through 3E.

[0039] Reference is now made to FIGS. 2A through 2C. These are schematic views of each view of operating head 40 disposed at distal portion 34 of delivery tool 30 according to some uses of the present invention. As shown, according to some uses of the present invention, operating head 40 includes an expandable element 50, an implant 70, and a cutting electrode 60. Operating head 40 is shown in FIGS. 2A through 2C in an expanded operating state.

[0040] Expandable element The expandable element 50 is typically expanded within the urethra so as to expand the urethra in the region to be treated. For example, the expandable element 50 comprises an inflatable balloon. In some applications, the expandable element 50 is a self-expanding device configured to self-expand when released from the delivery tool. In some applications, the expandable element 50 is configured to be expanded and / or collapsed (in the case of a balloon, inflated and / or deflated) in response to the user's desire. In some applications, the expandable element 50 is made of one or more materials such as PET, nylon, silicon, latex, polyurethane, and / or Pebax®. In some applications, the internal volume of the expandable element 50 is from about 2 cc to about 10 cc, such as 5 cc. Optionally, it is from about 1 cc to about 15 cc, such as 3 - 4 cc, such as 3 - 7 cc. Optionally, it is from about 10 cc to about 30 cc. In some applications, the diameter of the expandable element 50 is from about 10 mm to about 20 mm. Optionally, it is from about 5 mm to about 35 mm. Optionally, it is from about 3 mm to about 50 mm. In some applications, the expandable element 50 can be inflated to an internal pressure from about 1 atm to about 20 atm. Optionally, it is from about 0.5 atm to about 30 atm. Optionally, it is from about 5 atm to about 50 atm. In some applications, the expandable element 50 communicates with the inlet / outlet 28 to facilitate expansion and contraction of the expandable element 50.

[0041] In some applications, the expandable element 50 comprises a transparent or partially transparent expandable element, such as a transparent balloon, and is configured to facilitate visualization of the region of the urethra being treated by an imaging device through the expandable element.

[0042] In some applications, the expandable element 50 does not comprise a balloon. In some such applications, the expandable element 50 typically comprises a mechanical dilator, such as an umbrella-shaped dilator, configured to expand within the urethra so as to expand the urethra in the region to be treated.

[0043] Implant The implant 70 is disposed on the outer surface of the expandable element 50 and is configured to be implanted within the wall of the urethra (i.e., within the tissue surrounding the lumen of the urethra) to overcome urethral stricture caused by an enlarged prostate and to maintain the urethra in an expanded state.

[0044] The implant 70 is configured to be delivered to a stenotic location in the urethra in a helical configuration wrapped around a radially collapsed expandable element. When the distal portion of the delivery tool reaches a location within the urethra to be treated, the expandable element 50 is expanded, and the implant 70 is released onto a C-shaped open ring (e.g., omega-shaped) disposed on the outer surface of the expandable element 50, as shown in FIGS. 2A through 2C. Typically, the C-shaped open ring implant has a flat surface.

[0045] In some applications, when the expandable element 50 is expanded and not constrained by the surrounding tissue, the implant 70 is released into a configuration, for example, as shown in FIGS. 5A through 5B. In this configuration, the implant 70 is shaped to define a generally straight central section disposed between two curved end sections on either side of the central section. However, when released within the urethra, the implant typically assumes a shape generally the same as the shape shown in (and described with reference to) FIGS. 2A through 2C. This is because the central section is prevented from becoming straight due to the ends of the implant being constrained by the surrounding tissue.

[0046] In some applications, the implant 70 includes one or more of stainless steel, titanium, PET, PEEK, and / or PA. In some applications, the implant 70 includes an elastic material such as a shape memory material such as nitinol. In some applications, the implant 70 is coated with a biocompatible electrical insulation coating, such as a parylene coating.

[0047] In some applications, the length of the implant 70, when unconstrained, is between 30 mm and 100 mm, such as between 40 mm and 80 mm, such as between 50 mm and 70 mm.

[0048] In some applications, the thickness of the implant 70 ranges from 0.01 mm to 1 mm, such as from 0.1 mm to 0.8 mm, such as from 0.3 to 0.6 mm, such as 0.1 mm, 0.25 mm, 0.3 mm, or 0.5 mm. Generally, a thinner implant 70 is more suitable for promoting improved healing by being implanted deeper into the tissue compared to a thicker implant.

[0049]

[0048] In some applications, the width of the implant 70 ranges from 0.5 mm to 4 mm, such as from 0.7 mm to 2 mm, such as from 1 mm to 1.5 mm, such as 0.5 mm, 0.7 mm, 1 mm, 1.3 mm, 2 mm, 3 mm. In some applications, due to the relatively small width, it can be inserted deeper into the tissue compared to a wider implant. Additionally or alternatively, around an implant with a relatively small width, the tissue around the implant heals better.

[0050] In some applications, the force applied by the implant 70 to the urethral tissue ranges from 25 gr to 500 gr, such as from 50 gr to 100 gr, such as from 40 gr to 150 gr, such as 50 gr, 60 gr, 70 gr, 100 gr, 120 gr.

[0051] In some applications, the implant 70 is configured to remain in the patient's body for a predetermined period and then be removed from the body. For example, the implant 70 is configured to remain in the patient's body for 3 months, 6 months, 12 months, 36 months or more. Alternatively, the implant 70 is formed of a biodegradable material. In some such applications, the implant 70 biodegrades after a period selected by the physician, such as after 3 months, 6 months, 12 months, or 36 months. Alternatively, the implant 70 is configured to remain in the patient's body for an even longer period.

[0052] Cutting electrode The operating head 40 of the device 20 further includes a cutting electrode 60 configured to create an implant receiving incision in the wall of the urethra to create a region of a shape and size that accommodates the implant 70. The cutting electrode 60 passes an electric current (e.g., a diathermy current) through the tissue of the urethra to form an implant receiving incision in the tissue surrounding the lumen of the urethra by application of the current. Typically, the implant 70 is electrically insulated from the cutting electrode 60.

[0053] As shown in FIGS. 2A through 2C, the cutting electrode 60 is typically disposed on the outer surface of the implant 70 (the surface of the implant 70 facing the wall of the urethra). When the expandable element 50 expands within the urethra and the implant 70 opens into a C-shaped open ring configuration, the cutting electrode 60 is positioned on the implant 70 such that when the cutting electrode 60 contacts the tissue of the urethra and current is passed through the cutting electrode 60, an implant receiving incision is formed in the tissue of the urethra.

[0054] The cutting electrode 60 typically includes a stationary electrode (i.e., an electrode configured to form an implant receiving incision without moving). As shown in FIGS. 2A through 2C, the cutting electrode 60 is formed to conform to the shape of the implant 70 such that an implant receiving incision is formed in the shape of the implant 70 substantially without movement of the cutting electrode, e.g., rotation. In some applications, by being configured to form an implant receiving incision without moving, damage to surrounding tissue can be reduced or prevented compared to cases where it is necessary to move, e.g., rotate, the electrode (and / or additional portions of the operating head) to form the implant receiving incision.

[0055] In some applications, the cutting electrode 60 forms an implant receiving incision while cauterizing tissue by the application of current. Thus, when current is applied by the cutting electrode 60, an implant receiving incision is formed in the tissue surrounding the lumen of the urethra, and at the same time, cauterization of the tissue occurs. As a result, bleeding from the tissue that can occur by making an incision in the tissue is typically reduced or prevented. Further, if bleeding occurs from the tissue incision, the heat generated by the application of current by the cutting electrode 60 typically causes the blood to coagulate rapidly, thereby further ensuring reduction or prevention of bleeding during use of the device 20.

[0056] In some applications, the implant 70 is deployed while the cutting electrode 60 is creating an implant receiving incision or after the incision is completed. Typically, the implant is deployed against the wall of the urethra and at least partially embedded in the wall of the enlarged portion of the prostate surrounding the stenotic portion of the urethra.

[0057] Typically, the cutting electrode 60 is releasably coupled to the implant 70 and configured to be withdrawn from the urethra after forming the incision. The cutting electrode 60 is typically pulled proximally until it is removed from the urethra and the patient's body. In some applications, the proximal extension from the electrode (such as a thread or wire) is disposed in the delivery tool 30 such that pulling the proximal extension from the electrode in the proximal direction causes the cutting electrode to be withdrawn from the urethra.

[0058] In some applications, the cutting electrode 60 is configured to create an implant receiving incision in tissue having a depth of 1 mm to 20 mm, such as 4 mm to 10 mm, such as 2 mm to 8 mm, such as 3 mm, 5 mm, 7 mm, 10 mm, 12 mm, or 15 mm.

[0059] In some applications, as will be described in more detail below, the cutting electrode 60 is releasably coupled to the implant 70 using one or more sutures (or any type of securing wire). Typically, when current is passed through the cutting electrode, the cutting electrode is detached from the implant by burning of the suture.

[0060] In some applications, additional or alternative to the cutting electrode 60, the implant 70 or a part thereof is configured to pass an electric current through the tissue of the urethra to form an incision in the tissue of the urethra. In some such applications, both the cutting electrode 60 and the implant 70 pass an electric current through the tissue surrounding the lumen of the urethra to form an implant receiving incision in the tissue. Alternatively, the device 20 does not include the cutting electrode 60. Instead, the implant 70 forms an implant receiving incision in the wall of the urethra by applying an electric current to the tissue surrounding the lumen of the urethra to form an implant receiving incision in the tissue, and is deployed within the incision while the incision is being made.

[0061] Refer again to FIGS. 1A-1B and FIGS. 2A-2C. An example of an additional (or optional) element of the device 20 will be described below.

[0062] Implant carrier and / or implant holder In some applications, the device 20 includes additional elements configured to facilitate delivery and release of the implant 70 from the outer surface of the expandable element 50 at a selected location. For example, the device 20 includes one or more implant carrier arms 74 and / or implant holders 72. The implant carrier arms 74 are typically coupled to the shaft 36 and the implant 70 and are disposed outside the outer surface of the expandable element. The implant carrier arms 74 are typically configured to release the implant into the implant receiving incision after or during the formation of the incision by the cutting electrode.

[0063] The implant holder 72 is typically configured to limit the detachment of the implant 70 from the expandable element 50 and the insertion of the implant into the urethral wall. The implant 70 is disposed between the implant carrier arm and the implant holder such that the implant is held in place by the implant carrier arm and the implant holder. When it is desired to deploy the implant 70 within the tissue, the implant holder 72 can be withdrawn in the proximal direction, and after or during the formation of the implant receiving notch by the cutting electrode 60 as described above, the implant 70 can be implanted into the tissue. The implant carrier arm 74 and / or the implant holder 72 are typically coated with a biocompatible electrical insulation coating, such as a parylene coating. In some applications, the implant holder 72 is made of a biocompatible plastic polymer.

[0064] Imaging device In some applications, the device 20 further comprises an imaging device (camera or optical device) disposed on the delivery tool and configured to provide visualization of the region of the urethra to be treated and / or the implantation procedure. Typically, the device 20 incorporates an imaging device 26 (such as a camera and / or an optical fiber). FIG. 1A shows the proximal end of the imaging device 26 incorporated in the device 20. The imaging device 26 typically extends from the proximal portion 32 of the delivery tool 30 to the vicinity of the expandable element 50, for example, slightly proximal to the expandable element (as shown in FIGS. 3B to 3C). As described above, the expandable element 50 is typically transparent (or partially transparent) to provide visualization of the treatment region of the urethra through the expandable element. In some applications, the imaging device 26 is configured to provide a distal-facing view and / or a laterally-facing view through the opening 29 of the delivery tool 30.

[0065] In some applications, the field of view of the imaging device 26 is from 0 degrees (i.e., the view facing distally) to about ±90 degrees, optionally from 0 degrees to ± about 70 degrees, and optionally from 0 degrees to ± about 120 degrees. Typically, the imaging device 26 is configured to enable a user to navigate the urethra, visualize areas of urethral stricture, and place the visualized implant 70 in a desired location.

[0066] Reference is now made to FIGS. 3A, 3B, 3C, 3D, 3E and 3F. These are schematic views of a device 20 for the treatment of the urethra advanced and deployed within the urethra to expand a stenotic region of the urethra according to some applications of the present invention.

[0067] FIGS. 3A and 3B show the device 20 advancing distally within the urethra towards the area 92 of the urethra to be treated due to the enlarged area 92 stenosed by the hypertrophy of the prostate 80. The direction of distal advancement of the device 20 is indicated by arrow A2. When the distal portion of the delivery tool 30 reaches the stenosed location in the urethra, a portion of the delivery tool 30 is withdrawn proximally (in the direction indicated by arrow A3), and the operating head 40 is exposed (FIG. 3C). Typically, during distal advancement of the delivery tool 30 from the urethra, the expandable element 50 is in a collapsed state, and the implant 70 is wrapped around the collapsed expandable element. The cutting electrode 60 is typically disposed around the outer surface of the implant 70.

[0068] As shown in FIGS. 3D and 3E, when the operating head 40 is exposed, the extensible element 50 can be extended (e.g., by self - extension and / or by inflation of the inflation lumen 37). As shown in FIG. 3D, in some applications, the extensible element 50 comprises an inflatable balloon 50. This inflatable balloon, when inflated within the urethra, widens the urethra in the area to be treated and radially extends the implant 70 from the configuration shown in FIG. 3C where the implant 70 is wound around the extensible element to a C - shaped open - ring configuration (e.g., an omega shape as shown from FIG. 3D to FIG. 3E). FIG. 3D shows the start of inflation of the inflation balloon, and FIG. 3E shows the inflation balloon in a fully inflated state for expanding the urethra. As described above, the C - shaped open - ring implant typically has a flat surface.

[0069] The implant 70 is disposed on the outer surface of the inflatable balloon, and the cutting electrode 60 is disposed on the outer surface of the implant 70. The cutting electrode 60 passes an electric current through the tissue to form an incision in the tissue (the electric current is indicated by reference numeral 64 in FIG. 3E). Further, as shown in FIG. 3E, the shape of the cutting electrode 60 conforms to the shape of the implant 70 such that the cutting electrode 60 forms an incision in the shape of the implant 70 without moving the electrode, e.g., without rotating it. In other words, the cutting electrode 60 remains stationary while passing an electric current through the tissue to form the incision. Since the cutting electrode has a shape that conforms to the shape of the implant 70, the implant - receiving incision is formed in the shape of the implant 70 substantially without rotation of the cutting electrode. In some applications, by being configured to form the implant - receiving incision without movement, compared to cases where it is necessary to rotate the electrode (and / or additional parts of the operating head) to form the implant - receiving incision, damage to the surrounding tissue can be reduced or prevented.

[0070] In some applications, after or during the cut being formed by the cutting electrode, a portion of the implant (usually the central portion of the implant) held by one or more implant carrier arms 74 and / or implant holder 72 is released from the outer surface of the expandable element 50, enabling the implant 70 to be implanted into the tissue. For example, the portion of the implant held by one or more implant carrier arms 74 and / or implant holder 72 is released by pulling the implant holder 72 in the proximal direction as described above.

[0071] As described above, in some applications, the expandable element 50 is transparent. The transparency of the expandable element typically facilitates visualization of the stenotic location of the urethra by the imaging device 26 even at the stage shown in Fig. 3D (when the expandable element expands at the stenotic location).

[0072] Fig. 3F shows the implant 70 deployed through the wall of the urethra in the tissue of the prostate 80. As shown in the figure, the implant 70 maintains the urethra in an expanded state in the region stenosed by the prostate. In Fig. 3F, the cutting electrode 60 has already been withdrawn (indicated by reference numeral 83) after forming the implant receiving cut. Further, the expandable element is collapsed (e.g., by a deflated balloon). Fig. 3F shows the delivery tool being withdrawn proximally in the direction of arrow A4. (Note that Fig. 3F shows the operating head 40 being completely withdrawn into the shaft 36 when the delivery tool is withdrawn proximally, but there may be cases where the delivery tool is withdrawn proximally and the operating head 40 remains collapsed and is not withdrawn inside the shaft 36.) Typically, the implant 70 remains implanted in the urethral wall and / or the tissue of the prostate, maintaining the urethra in an expanded state and alleviating the symptoms of BPH.

[0073] As described above, in some applications, when the expandable element 50 is expanded and not constrained by the surrounding tissue, the implant 70 unfolds into the configuration shown, for example, in FIGS. 5A - 5B. In this configuration, the implant 70 is shaped to define a generally straight central section disposed between two curved end sections on either side of the central section. However, when released within the urethra (e.g., in both the steps shown in FIGS. 3E and 3F), the implant typically assumes a shape generally the same as that shown in FIGS. 2A - 2C (and described with reference to FIGS. 2A - 2C). This is because the central section is prevented from becoming straight due to the ends of the implant being constrained by the surrounding tissue.

[0074] Reference is made to FIG. 4. This is a flowchart showing the steps of a method for the treatment of the urethra, performed in some applications of the present invention. In some applications, a device comprising an expandable element (inflatable element), an implant, and a cutting electrode is advanced distally to a region narrowed by benign prostatic hyperplasia within the urethra (step 110). The urethra is expanded at the narrowed site by expanding the expandable element (step 120). Typically, thereafter, the cutting electrode forms incisions in the wall of the urethra by application of an electric current (diathermy current) by the electrode, with the electrode kept stationary and substantially without rotating the electrode (step 130). The implant is released into the incisions (step 140), and the urethra is maintained in an expanded state (step 150). After release of the implant, the delivery tool is manipulated within the urethra in the proximal direction until the device is completely removed.

[0075] Still referring to FIG. 4, in some applications, prior to advancing the device 20 distally within the urethra (step 110), the length of the enlarged prostate is measured and, accordingly, the center of the narrowed region of the urethra (narrowing of the urethra by the enlarged prostate) is estimated. Next, the device 20 is positioned within the urethra based on the measurement of the prostate and the estimated position of the narrowing.

[0076] Reference is made to FIGS. 5A - 5B. These are schematic views of the components of the operating head 40 disposed at the distal portion of the device for the treatment of the urethra, according to some uses of the present invention. As described above with reference to FIG. 2, the operating head 40 comprises an expandable element 50, an implant 70, and a cutting electrode 60.

[0077] FIG. 5A shows the operating head 40 with the expandable element 50 in a contracted state and the implant 70 before being released into the tissue. (Note that the configuration shown in FIG. 5A is illustrated for explanatory purposes. In actual use, the implant 70 is usually wound around the contracted expandable element 50 or generally takes the configuration of a C - shaped open ring (omega shape) due to binding to the tissue as described above.)

[0078] FIG. 5B shows the operating head 40 in an operating state, comprising the expandable element 50 in an expanded state, the implant 70, and the cutting electrode 60. Note that both FIGS. 5A and 5B show the implant without surrounding tissue. In the configuration shown in FIGS. 5A - 5B, as described above, the implant is shaped to define a generally straight central section disposed between two curved end sections on either side of the central section. However, when the implant is released into the urethra using the techniques described herein, the implant is prevented by the pressure of the surrounding tissue from taking its completely unconstrained configuration and usually takes an expanded C - shaped (omega shape).

[0079] As shown in FIGS. 5A and 5B, in some applications, the cutting electrode 60 is releasably secured to the implant 70 by one or more sutures 65. Typically, one or more sutures 65 are coupled to the implant 70 and maintain the cutting electrode 60 positioned on the outer surface of the implant 70 during delivery and radial expansion of the implant 70 prior to application of current by the cutting electrode 60. When current is passed through the cutting electrode 60, the suture 65 is separated from the cutting electrode 60 (usually by melting / burning due to heat generated by the current), and an implant receiving incision is formed in the tissue of the urethra. As the implant receiving incision is formed in the tissue of the urethra, the implant 70 is deployed into the incision in the wall of the urethra and the tissue of the prostate. As described above, typically, the cutting electrode 60 is withdrawn and removed from the body after the implant receiving incision is formed. In some applications, the suture 65 is made of a biocompatible and bioabsorbable material such that any portion of the suture remaining after application of current by the cutting electrode 60 is absorbed into the patient's body. Alternatively, the suture 65 is non-absorbable and is not absorbed in the body. Generally, any portion of the suture (which may be absorbable or non-absorbable) remaining after application of current by the cutting electrode 60 is withdrawn from the urethra together with other parts of the device 20 (e.g., using a grasper or other suitable tool). In some applications, multiple sutures 65 are coupled to each other by a binding wire / suture such that any sutures remaining after application of current by the cutting electrode can be removed together in a single extraction.

[0080] Additionally or alternatively, the cutting electrode 60 is releasably coupled to the implant 70 by other types of coupling techniques and devices. For example, the cutting electrode 60 may be releasably coupled to the implant 70 using mechanical coupling elements (such as clips) or adhesives (such as glue).

[0081] Reference is now made continuously to FIGS. 5A - 5B. As shown, in some applications, the cutting electrode 60 has a coiled tip 62 (similar to one or more coil springs). In normal use, each coiled tip 62 generally prevents the ends of the cutting electrode 60 from passing through sutures that are disposed closest to the ends of the implant, thereby holding each end of the cutting electrode in place relative to the implant 70. On the other hand, if, due to application of current through the cutting electrode, one or more sutures 65 are not separated from the cutting electrode 60 (e.g., due to failure of the cutting electrode) and removal (and optionally redeployment) of the device 20 is required, the coiled tips 62 enable the cutting electrode 60 to be easily and safely withdrawn by being actively pulled through one or more sutures 65 such that the coiled tips straighten and pass through one or more sutures. In this regard, the coiled tips, for example, enable removal of the cutting electrode from the urethra as compared to a case where the tip of the cutting electrode 60 is fixed to the implant with a clamping device. Typically, in the event of the above-described failure, when the ends of the cutting electrode are pulled through one or more sutures, the cutting electrode 60 is withdrawn by being pulled in the proximal direction until it is completely removed from the patient's body.

[0082] Reference is now made again to FIGS. 2A - 2C and FIGS. 5A - 5B. As described above with reference to FIGS. 2A - 2C, the device 20 includes one or more implant carrier arms 74 coupled to the shaft 36 and the implant 70. As shown in FIG. 2, the implant carrier arms 74 generally extend from the shaft 36 and contact and support the implant 70. Further, in some applications, the implant carrier arms assist in maintaining the urethra in an expanded state by applying pressure to the wall of the urethra in a region proximal to the expandable element 50 (shown in FIGS. 3D and 3E).

[0083] In some applications, device 20 includes two to four, for example three, implant carrier arms 74. Alternatively, device 20 includes fewer implant carrier arms 74. For example, as shown in FIG. 5A, device 20 includes only a single implant carrier arm 74 that extends from shaft 36 and contacts implant 70. Reducing the number of implant carrier arms 74 generally simplifies the delivery and release of implant 70 into an incision formed in the urethra. Additionally or alternatively, a potential advantage of reducing the number of implant carrier arms 74 is to reduce metal-to-metal contact between implant carrier arm 74 and implant 70.

[0084] As further shown in FIG. 5A, in some applications, device 20 additionally includes one or more radial arms 76. In applications where device 20 includes a reduced number of implant carrier arms 74 (e.g., a single implant carrier arm 74) that reach implant 70, device 20 typically includes one or more radial arms 76 that assist in maintaining the urethra in an expanded state by applying pressure to the wall of the urethra in a region proximal to expandable element 50. Radial arm 76 typically has a length sufficient to apply pressure to the wall of the urethra proximal to expandable element 50 when expandable element is expanded to overcome urethral stricture. However, since radial arm 76 is not long enough to reach and contact implant 70, potential metal-to-metal contact between radial arm 76 and implant 70 is prevented. Typically, by applying pressure to the wall of the urethra proximate expandable element 50, the wall expands this region so that this site is visualized by imaging device 26.

[0085] Note that generally, the device 20 is structured to avoid voltage breakdown. For example, this can be achieved by reducing the contact between metals among the components of the device 20, by applying an insulating coating to the metal components, and / or by replacing the metal components with plastic ones. For example, as described above, the implant carrier arm 74 and / or the implant holder 72 are typically coated with a biocompatible electrical insulating coating, such as a parylene coating. Additionally or alternatively, the implant holder 72 is made of a biocompatible electrically non-conductive polymer, such as biocompatible plastic.

[0086] Reference is made to FIGS. 1A through 5B. The device 20 is typically controlled by a user via user interface elements (e.g., knobs, buttons, and / or levers) disposed on the handle to transmit manual movement or, typically, to activate a motor (e.g., a linear motor and / or a rotary motor) disposed on the handle. As described herein, the implant receiving incision is formed in the tissue of the urethra while keeping the cutting electrode stationary. In other words, the implant receiving incision is generally formed in the shape of the implant with substantially no movement of the electrode and / or the implant, e.g., without rotation. The stationary electrode enables the device 20 to be operated in a partially or fully mechanical manner compared to a moving electrode, avoiding the need for complex software and / or hardware to control and synchronize the movement of the cutting electrode and the release of the implant. Note that generally, the device 20 is configured to be operated in a fully mechanical manner.

[0087] Experimental data Reference is made to FIGS. 6A through 6B, FIGS. 7A through 7B, and FIGS. 8 through 9. These are photographs of experimental data obtained by some applications of the present invention. More specifically, the experiments described below with reference to FIGS. 6A through 6B, FIGS. 7A through 7B, and FIGS. 8 through 9 were conducted by the inventors using the device 20 and techniques described herein according to the applications of the present invention.

[0088] First, FIGS. 6A and 6B are referred to. These are examples of the urethra of a patient using the device 20, photographs before treatment (FIG. 6A) and after treatment (FIG. 6B), for the treatment of the urethra narrowed by benign prostatic hyperplasia (BPH) according to some uses of the present invention. FIG. 6A shows the urethra 90 having a narrowed region 92 due to the hypertrophy of the prostate 80. FIG. 6B shows the prostate 80 after being treated by the device 20 according to the technique of using the device 20 described herein. As shown in FIG. 6B, after the use of the device 20, the obstruction of the urethra is overcome so that the region 92 of the urethra is no longer narrowed.

[0089] Now, FIGS. 7A and 7B are referred to. These are photographs showing the contrast fluid injected from the urethra of a patient after treating the patient using the device 20 and the technique described herein for the treatment of the urethra narrowed by benign prostatic hyperplasia (BPH) according to some uses of the present invention. FIG. 7A shows the urethra 90 after treatment by the device 20 and before the contrast fluid 82 is injected into the urethra 90. FIG. 7B shows that the contrast fluid 82 is injected from the urethra 90 and reaches the bladder 94 without obstructing the urethra as a result of the treatment by the device 20.

[0090] Now, FIGS. 8 and 9 are referred to. These are photographs showing the implant 70 implanted in the hypertrophied prostate according to some uses of the present invention. As described above with reference to FIGS. 1A to 5B, the implant 70 is implanted in the prostate and maintains the urethra in an expanded state. As shown in FIGS. 8 to 9, the implant 70 is completely implanted in the prostate 80 without interfering with the flow of urine through the urethra and without being exposed. As shown, the implant 70 is typically shaped to define an omega-shaped implant that is deployed at the center of the prostate and implanted in the prostate tissue at a depth of 2.5 mm to 5 mm (FIG. 9).

[0091] It will be understood by those skilled in the art that the present invention is not limited to what is particularly shown and described herein. Rather, the scope of the present invention includes both combinations and sub-combinations of the various features described herein, as well as those variations and modifications thereof which would occur to those skilled in the art upon reading the foregoing description and which are not found in the prior art.

Claims

1. A device for treating a narrowed urethra, A delivery tool having a proximal portion and a distal portion, The distal portion is configured to advance to a location within the urethral region to be treated. An extensible element configured to be stretched within the urethra in order to widen the urethra within the area to be treated, comprising an extensible element defining an outer surface, An implant positioned outside the outer surface of the stretchable element, A cutting electrode is provided, which is removably coupled to the outer surface of the implant and configured to pass an electric current through the tissue of the urethra, thereby forming an implant-receiving incision in the tissue surrounding the lumen of the urethra. Delivery tools including, The device wherein the cutting electrode is shaped to conform to the shape of the implant so as to form the implant-receiving incision to the shape of the implant, substantially without movement of the cutting electrode.

2. The apparatus according to claim 1, wherein the cutting electrode is shaped to conform to the shape of the implant so as to form the implant receiving incision to the shape of the implant without substantially any rotation of the cutting electrode.

3. The apparatus according to claim 1, wherein the cutting electrode is configured to be withdrawn from the urethra after the implant receiving incision has been formed.

4. The apparatus according to claim 1, wherein the cutting electrode has a distal portion releasably coupled to the implant and a proximal extension portion positioned on the delivery tool, and the cutting electrode is configured to be withdrawn from the urethra by pulling the proximal extension portion of the electrode in the proximal direction.

5. The device according to claim 1, wherein the implant is configured as a C-shaped open ring.

6. The apparatus according to claim 1, wherein the implant is configured to wrap around the expandable element while the distal portion of the delivery tool is advanced to the location within the region of the urethra to be treated.

7. The apparatus according to claim 1, wherein the thickness of the implant is 0.01 to 1 mm.

8. The device according to claim 1, wherein the width of the implant is 0.5 to 4 mm.

9. The apparatus according to claim 1, wherein the cutting electrode is formed of nitinol.

10. The apparatus according to claim 1, wherein the implant is electrically insulated from the cutting electrode.

11. The apparatus according to claim 1, wherein the implant is configured to be deployed within the incision, thereby maintaining the urethra in an expanded state within the region of the incision.

12. The apparatus according to claim 1, further comprising an imaging device positioned on the delivery tool, configured to provide visualization of the region of the urethra being treated by the imaging device.

13. The apparatus according to any one of claims 1 to 12, wherein the stretchable element includes an inflatable balloon.

14. The apparatus according to claim 13, wherein the inflatable balloon is transparent.

15. The apparatus according to claim 14, further comprising an imaging device positioned on the delivery tool, wherein the inflatable balloon is configured to provide visualization of the region of the urethra being treated by the imaging device via the inflatable balloon.

16. The apparatus according to any one of claims 1 to 12, further comprising one or more sutures configured to be releasably coupled to the implant before the current is applied by the cutting electrode.

17. The apparatus according to claim 16, wherein the one or more sutures are configured to be separated from the implant by the application of the current, thereby freeing the cutting electrode from the implant.

18. The apparatus according to claim 16, wherein the cutting electrode is provided with a coiled tip at each end of the cutting electrode, and each coiled tip is configured to hold each end of the cutting electrode in place relative to the implant by preventing the end of the cutting electrode from passing through one of the sutures positioned closest to the end of the implant, and when the cutting electrode is pulled proximal, the coiled tip straightens out and passes through one or more sutures.

19. The apparatus according to any one of claims 1 to 12, further comprising a single implant carrier arm extending from the axis of the delivery tool and positioned outside the outer surface of the extensible element, wherein the implant carrier is configured to release the implant into the implant-receiving notch after the cutting electrode has formed the implant-receiving notch.

20. The apparatus according to claim 19, wherein the implant carrier arm is covered with an electrically insulating coating.

21. The implant carrier arm is further equipped with an electrically non-conductive implant holder, The implant is configured to be positioned between the implant carrier arm and the implant holder so that the implant is held in place by the implant carrier arm and the implant holder. The apparatus according to claim 19, wherein the implant holder is configured to be withdrawn proximal to the implant carrier arm so that the implant is released by the implant carrier arm into the implant receiving notch.

22. (a) When the expandable element is in an expandable state, the region adjacent to the expandable element is sufficient to apply pressure to the wall of the urethra and expand the urethra, (b) the apparatus according to claim 19, further comprising at least one radial arm having a length not sufficient to contact the implant.

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