Prostatic urethra implant

Abstract

To provide a prostatic urethra implant for treating prostate enlargement that both side lobe and median lobe become enlarged.SOLUTION: Prostatic urethra implant includes: at least two incision wires in a closed shape each of which has a proximal section, a distal section, and a lateral section extending in a longitudinal between the proximal section and the distal section; and a fixing wire for pressure in a closed shape for pressing the median lobe when the prostatic urethra implant is located in the prostatic urethra. Each of the at least two incision wires and the fixing wire for pressure is elastic and has shape memory, thereby has an extended configuration, and is compressible into a compression configuration. In the extended configuration, the incision wires incise tissues in the prostatic urethra via outward pressure in a radial direction, and the fixing wire for pressure applies outward pressure in the radial direction to the median lobe.SELECTED DRAWING: Figure 2A

Description

[Technical Field]

[0001] The technology of the present disclosure relates generally to systems and methods for reducing prostatic hyperplasia (e.g., as a result of benign prostatic hyperplasia), as well as prostatic urethral implants for use in systems and methods for enlarging the prostatic urethra and immobilizing the middle lobe of the prostate. [Background technology]

[0002] The prostate is a walnut-sized gland that forms part of the male reproductive system. It is located in front of the rectum and just below the bladder, where urine is stored. The urethra is the tube that connects the bladder to the penis, through which urine can leave the body. In the male reproductive system, the ejaculatory duct is the tube that connects the testes to the urethra, through which semen can also leave the body. The prostate surrounds a portion of the urethra (referred to herein as the prostatic urethra), and the ejaculatory duct also passes through the prostate to connect with the prostatic urethra. Anatomically, the prostate itself is composed of four lobes: the anterior, middle, posterior, and lateral lobes. The anterior, middle, and posterior lobes surround the urethra, and the ejaculatory ducts pass through the middle and posterior lobes. The lateral lobe is located around the anterior, middle, and posterior lobes. Anatomical landmarks on the prostatic urethra used to classify specific urethral developmental disorders are known as the verumontanum or seminal coiliculus. The verumontanum is located between the ejaculatory ducts, the prostatic locules, and the prostatic ducts, and is inferior to the urethral crest.

[0003] Reference is now made to Figures 1A and 1B, which are schematic diagrams of the male reproductive system and prostate gland, generally referenced 10 and 40, respectively, as known in the art. Referring to Figure 1A, a schematic diagram of the male reproductive system is shown from a sagittal view. As can be seen, a bladder 12 connects with a urethra 16, which drains into a penis 28. Below the bladder 12, a prostate gland 14 surrounds the urethra 16. The portion of the urethra 16 surrounded by the prostate gland 14 is shown as the prostatic urethra 24. Multiple ejaculatory ducts 18 join the urethra 16 at the prostatic urethra 24. Within the section of the prostatic urethra 24, the urethral ridge 26, prostatic ventricles 20, and verumontanum 22 are shown. Referring to Figure 1B, a schematic diagram of the prostate gland is shown from a sagittal view 42A and a transverse view 42B. Identical elements in the sagittal view 42A and the transverse view 42B are designated using the same reference numerals. As can be seen in the sagittal view 42A, the anterior lobe 44, the posterior lobe 46, and the middle lobe 48 surround the urethra 52. The ejaculatory duct 54 passes through the posterior lobe 46 and the middle lobe 48. Also shown is the verumontanum 56 at the proximal end of the posterior lobe 46. As can be seen in the transverse view 42B, multiple lateral lobes 50 surround the anterior lobe 44, the posterior lobe 46, and the middle lobe 48, and the urethra 52 runs between the various lobes of the prostate gland.

[0004] Common medical conditions of the prostate include inflammation, noncancerous prostatic hyperplasia, and prostate cancer. Noncancerous prostatic hyperplasia, also known as benign prostatic hyperplasia, is a medical condition that primarily occurs in older men (generally over 50) in which the prostate gland increases in size but is not due to metastasis or uncontrolled cell proliferation. As the prostate gland enlarges and increases in size, as can be seen from its anatomical location in a human male as shown in Figure 1A, it can exert pressure on adjacent anatomical sites, such as the urethra, particularly the prostatic urethra, as well as the bladder neck (the lower part of the bladder that connects to the urethra) and the ejaculatory duct. Generally, when the prostate gland enlarges, it is the lateral lobe that enlarges and exerts pressure on the prostatic urethra. However, in some cases, the middle lobe can also enlarge. Prostatic hyperplasia can lead to many medical problems, such as benign prostatic hyperplasia (BPH) and prostatic bladder neck obstruction (BNO). BPH causes increased pressure in the prostatic urethra, making urination difficult and painful. BNO can cause complete obstruction of the prostatic urethra and an inability of the muscles around the bladder neck (e.g., the internal urethral sphincter) to relax and contract, making urination nearly impossible and usually requiring medical intervention to remove urine from the bladder.

[0005] Treatments for medical problems resulting from prostatic hyperplasia range from orally ingested medications (to reduce the size of the prostate by reducing hormone production), various types of stents and implants to enlarge the prostatic urethra, the use of catheters to allow urine to drain from the bladder to the penis, and surgical procedures to remove either a portion of the prostate (such as transurethral resection of the prostate) or the entire prostate (such as prostatectomy). Stents and implants for opening the prostatic urethra are known in the art. International Publication No. 2006 / 040767 to Kilemnik, entitled "Prostate Treatment Stent," is directed to a tissue-dissecting implant. The implant is spring-shaped and includes multiple rings elastically connected between them. Adjacent rings apply pressure to the tissue trapped between the rings, thereby pinching the trapped tissue and inducing necrosis.

[0006] U.S. Patent Application Publication No. 2011 / 0276081 to Kilemnik, entitled "Radial Cutter Implant," is directed to an implant for applying radial force to surrounding tissue. The implant includes wires for applying radial pressure to surrounding tissue. Each wire extends in a different radial direction, and therefore each wire applies pressure to a different tissue. The implant can further include a longitudinal central tube such that the wires are coupled to the proximal and distal ends of the tube. The tube supports the wires and provides structural stability to the implant. The distal end of the wire is positioned within a subject's bladder and can irritate the bladder.

[0007] U.S. Patent No. 11,304,724 to Kilemnik, entitled "Incising Implant For The Prostatic Urethra," is directed to an implant for forming an incision in a subject's prostatic urethra. The implant includes at least two closed-configuration wires, each having a proximal section, a distal section, and two longitudinal sections extending between the proximal and distal sections. Each of the closed-configuration wires is elastic and thus compressible to a compressed configuration. Each longitudinal section of each of the wires is joined to another longitudinal section of another of the wires. In the open configuration, the implant incises tissue within the prostatic urethra, with the wires bifurcating at the distal sections so that the distal sections form a simple closed curve at the end of the implant.

[0008] U.S. Patent No. 8,715,239 to Lamson et al., entitled "Devices, Systems, and Methods for Treating Benign Prostatic Hyperplasia and Other Conditions," is directed to a system including a rigid introducer device that can be used to facilitate insertion of an implant into the prostate. The implant includes a proximal anchor connected to a distal anchor by a tensioning element, and the introducer device includes a rigid elongated body insertable into the subject's urethra. The introducer device also includes a rigid endoscope lumen and a rigid working lumen configured to receive a cystoscope or other endoscopic device. The working lumen is used to position a prostatic compression implant and has an exit port that allows the implant to be advanced through the wall of the urethra to a location within or near the prostate.

[0009] Prior art techniques offer solutions to the pressure exerted on the prostatic urethra when the lateral lobes of the prostate enlarge, a more common form of BPH. However, enlargement of both the lateral and middle lobes of the prostate can lead to additional complications. As described below, the enlarged middle lobe can exhibit sufficient movement within the prostatic urethra to block the bladder neck after urination, thereby causing BNO. During regular urination in men, when the muscles around the bladder contract and compress the bladder, the muscles around the bladder neck (such as the internal urethral sphincter) relax, allowing urine into the prostatic urethra. As urine leaves the bladder, air pressure is generated within the bladder, which pushes urine from the bladder into the urethra. After urination ends, when the muscles around the bladder relax and the muscles around the bladder neck contract to close the bladder neck, negative air pressure and suction can be generated in the prostatic urethra. In cases of BPH in which only the lateral lobes of the prostate enlarge, negative air pressure may not affect the opening of the bladder neck. However, in cases of BPH in which the lateral and middle lobes are enlarged, negative air pressure (i.e., suction) can pull the enlarged middle lobe toward the bladder neck, thereby also causing BNO. Prior art treatment methods in such cases (BPH with an enlarged middle lobe and BNO) typically involve some form of laparoscopic surgery to remove a portion of the middle lobe to relieve symptoms. Therefore, there is a need for a minimally invasive treatment, such as an implant, that can open the prostatic urethra and treat the symptoms of BPH, while also preventing the middle lobe from obstructing the bladder, thereby treating the symptoms of BNO. [Prior art documents] [Patent documents]

[0010] [Patent Document 1] International Publication No. 2006 / 040767 Pamphlet [Patent Document 2] US Patent Application Publication No. 2011 / 0276081 [Patent Document 3] U.S. Patent No. 11,304,724 [Patent Document 4] U.S. Patent No. 8,715,239 Summary of the Invention

[0011] It is an object of the disclosed technology to provide a prostatic urethral implant for treating benign prostatic hyperplasia in which both the lateral and median lobes are enlarged.

[0012] The techniques of the present disclosure will be more fully understood and appreciated from the following detailed description taken in conjunction with the drawings, in which: [Brief explanation of the drawings]

[0013] [Figure 1A] 1 is a schematic diagram of the male reproductive system and prostate gland as known in the prior art. [Figure 1B] 1 is a schematic diagram of the male reproductive system and prostate gland as known in the prior art. [Figure 2A] FIG. 1 is a schematic illustration of a prostatic urethral implant for creating an incision in the tissue of the inner wall of the prostatic urethra and compressing the middle lobe, constructed and operative in accordance with an embodiment of the disclosed technology; [Figure 2B] FIG. 1 is a schematic illustration of a prostatic urethral implant for creating an incision in the tissue of the inner wall of the prostatic urethra and compressing the middle lobe, constructed and operative in accordance with an embodiment of the disclosed technology; [Figure 2C] FIG. 1 is a schematic illustration of a prostatic urethral implant for creating an incision in the tissue of the inner wall of the prostatic urethra and compressing the middle lobe, constructed and operative in accordance with an embodiment of the disclosed technology; [Figure 3A] FIG. 10 is a schematic illustration of a second prostatic urethral implant for creating an incision in tissue of the inner wall of the prostatic urethra, constructed and operative in accordance with another embodiment of the disclosed technology; [Figure 3B] FIG. 10 is a schematic illustration of a second prostatic urethral implant for creating an incision in tissue of the inner wall of the prostatic urethra, constructed and operative in accordance with another embodiment of the disclosed technology; [Figure 3C]FIG. 10 is a schematic illustration of a second prostatic urethral implant for creating an incision in tissue of the inner wall of the prostatic urethra, constructed and operative in accordance with another embodiment of the disclosed technology; [Figure 4] FIG. 10 is a schematic illustration of a third prostatic urethral implant for creating an incision in tissue of the inner wall of the prostatic urethra, constructed and operative in accordance with a further embodiment of the disclosed technique; [Figure 5A] FIG. 10 is a schematic illustration of a proximal niche of a proximal cap of a prostatic urethral implant constructed and operative in accordance with yet another embodiment of the disclosed technology; [Figure 5B] FIG. 10 is a schematic illustration of a proximal niche of a proximal cap of a prostatic urethral implant constructed and operative in accordance with yet another embodiment of the disclosed technology; [Figure 6A] FIG. 10 is a schematic illustration of a fourth prostatic urethral implant for creating an incision in tissue of the inner wall of the prostatic urethra, constructed and operative in accordance with yet a further embodiment of the disclosed technique; [Figure 6B] FIG. 10 is a schematic illustration of a fourth prostatic urethral implant for creating an incision in tissue of the inner wall of the prostatic urethra, constructed and operative in accordance with yet a further embodiment of the disclosed technique; [Figure 7] FIG. 10 is a schematic illustration of a fifth prostatic urethral implant for creating an incision in tissue of the inner wall of the prostatic urethra, constructed and operative in accordance with yet another embodiment of the disclosed technology. [Figure 8] 1 is a schematic illustration showing the placement of a prostatic urethral implant within a prostatic urethra, constructed and operative in accordance with yet a further embodiment of the disclosed technique; [Figure 9A] 10 is a schematic illustration of a method for deploying and withdrawing a prostatic urethral implant operable in accordance with yet another embodiment of the disclosed technique; [Figure 9B] 10 is a schematic illustration of a method for deploying and withdrawing a prostatic urethral implant operable in accordance with yet another embodiment of the disclosed technique; [Figure 9C] 10 is a schematic illustration of a method for deploying and withdrawing a prostatic urethral implant operable in accordance with yet another embodiment of the disclosed technique; [Figure 9D] 10 is a schematic illustration of a method for deploying and withdrawing a prostatic urethral implant operable in accordance with yet another embodiment of the disclosed technique; [Figure 9E] 10 is a schematic illustration of a method for deploying and withdrawing a prostatic urethral implant operable in accordance with yet another embodiment of the disclosed technique; [Figure 9F] 10 is a schematic illustration of a method for deploying and withdrawing a prostatic urethral implant operable in accordance with yet another embodiment of the disclosed technique; [Figure 9G] 10 is a schematic illustration of a method for deploying and withdrawing a prostatic urethral implant operable in accordance with yet another embodiment of the disclosed technique; [Figure 9H] 10 is a schematic illustration of a method for deploying and withdrawing a prostatic urethral implant operable in accordance with yet another embodiment of the disclosed technique; [Figure 9I] 10 is a schematic illustration of a method for deploying and withdrawing a prostatic urethral implant operable in accordance with yet another embodiment of the disclosed technique; [Figure 9J] 10 is a schematic illustration of a method for deploying and withdrawing a prostatic urethral implant operable in accordance with yet another embodiment of the disclosed technique; [Figure 9K] 10 is a schematic illustration of a method for deploying and withdrawing a prostatic urethral implant operable in accordance with yet another embodiment of the disclosed technique; [Figure 9L] 10 is a schematic illustration of a method for deploying and withdrawing a prostatic urethral implant operable in accordance with yet another embodiment of the disclosed technique; DETAILED DESCRIPTION OF THE INVENTION

[0014] The technology of the present disclosure overcomes the shortcomings of the prior art by providing a prostatic urethral implant positioned within (or near, e.g., within the bladder neck) the prostatic urethra. The implant includes a wire that applies a radial force to the tissue surrounding the inner wall of the prostatic urethra. Over time, the wire creates a longitudinal incision within the prostatic urethra, inducing infarction (i.e., tissue death due to lack of blood supply) therein. The incision and resulting infarction relieve the stricture of the prostatic urethra by killing the portion of tissue within the prostatic urethra that is causing the urethral obstruction. The implant also includes at least one anchor that holds the implant in place and simultaneously prevents migration of the implant into the bladder, while also applying pressure to the middle lobe of the prostate, thus preventing movement of the middle lobe (due to suction) after urination. Thus, the implant provides a solution to the narrowed prostatic urethra caused by BPH and a solution for preventing BNO due to middle lobe hypertrophy.

[0015] As explained above, in some cases of BPH, not only do the lateral lobes of the prostate enlarge, but the middle lobe may also enlarge. In such cases, the proximal side of the middle lobe closest to the prostatic urethra may form a spherical, pendulous end. Due to the suction generated during urination, when a man stops urinating, the suction from the bladder may pull the spherical, pendulous end toward the bladder neck, thereby causing BNO. Therefore, even when the prostatic urethra is free from the overall constriction caused by the enlargement of the lateral lobes, the spherical, pendulous end of the middle lobe still has enough movement to obstruct the bladder neck.

[0016] According to one embodiment of the disclosed technology, the implant is formed by three (or more) closed-shaped incision wires with at least one additional closed-shaped fixation wire, which acts as an anchor to limit movement of the bulbous, pendulous end of the enlarged middle lobe and prevent the implant from migrating toward the bladder. The incision wires and fixation wires are all connected with a hollow cap, providing a base structure for the implant while also allowing urine to pass through the implant. The shape of each incision wire can be broadly divided into a proximal section, a distal section, and two lateral sections extending between the proximal and distal sections. The fixation wires resemble the contours of a lobe or teardrop with a distal curvature to apply pressure radially outward. Each wire (incision and fixation) is made of elastic and shape-memory material, allowing it to be compressed within a sheath and then expand to its original shape upon release from the sheath.

[0017] The lateral sections of each incision wire are joined to the lateral sections of adjacent incision wires, thus joining the incision wires to form a wire frame. Each incision wire forms a face of the wire frame, with the joined lateral sections forming the edges of the wire frame. The edges of the wire frame apply outward radial pressure to the tissue of the inner wall of the prostatic urethra, thereby forming a longitudinal incision that relieves the urethral stricture and increases the urinary passage.

[0018] When the cutting wires apply pressure to the surrounding tissue, they press against each other (i.e., each wire presses against the adjacent wires joined at its respective lateral section). Therefore, the wire frame is self-supporting due to the supporting cutting wires. When the cutting wires apply a force to the tissue, the tissue applies an equal and opposite force (according to Newton's third law of motion). Therefore, the cutting wires press against the adjacent joined cutting wires. These joined cutting wires are then pressed against the inner wall of the tissue within the prostatic urethra. In this way, the wire frame is self-supporting, eliminating the need for additional support elements such as a central support tube. Additionally, each edge of the wire frame is formed by two joined cutting wires, thus doubling the pressure applied to the tissue and allowing for thinner wires.

[0019] In a first embodiment of the disclosed technology, the implant has two fixation wires, each shaped like a lobe, apex, or teardrop. The first fixation wire is used to secure the wire frame of the incision wire to prevent the implant from migrating into the bladder. The second fixation wire is used to secure the spherical, drooping end of the middle lobe to prevent it from moving when suction occurs after urination. Both the first and second fixation wires have an outward curvature, thereby applying outward radial pressure. The two fixation wires are connected to the hollow cap of the implant and have different lengths corresponding to the structure of the prostatic urethra to which they are attached. The first fixation wire is long enough to apply pressure to the verumontanum when the implant is positioned in the prostatic urethra, thereby preventing the implant from migrating toward the bladder. The first fixation wire essentially holds the implant in place without the need to permanently affix the implant to tissue within the prostatic urethra (e.g., without the need to use adhesives, sutures, or other means for connecting the implant to tissue within the body). The second fixation wire is long enough so that, when the implant is positioned within the prostatic urethra, the second fixation wire applies pressure to the spherical, pendulous end of the middle lobe, thereby preventing the spherical, pendulous end of the middle lobe from being sucked toward the bladder and obstructing the bladder neck after urination. Given the anatomical structure of the prostate and prostatic urethra and the fact that the implant is inserted into the urethra from the penis, the second fixation wire is longer than the first fixation wire because the spherical end of the middle lobe is distal to the penis relative to the verumontanum.

[0020] In a second embodiment of the disclosed technology, the implant has a single fixation wire with two extensions, the fixation wire having a forked shape. The first extension is used to secure the implant to the prostatic urethra, for example, by applying pressure to the verumontanum, while the second extension is used to apply pressure to the spherical end of the middle lobe. This embodiment is similar to the embodiment described above, but in this embodiment, the fixation wire has a monolithic structure and only one connection point with the hollow cap. In this embodiment, each extension performs the function of the respective fixation wire in the previous embodiment.

[0021] In a third embodiment of the disclosed technology, the implant has a single fixation wire shaped like a lobe, apex, or teardrop to apply pressure to the spherical end of the middle lobe. The single fixation wire in this embodiment is similar to the second fixation wire in the first embodiment described above. In this embodiment, other means are used to maintain the implant's position within the prostatic urethra and prevent it from migrating toward the bladder. For example, in this embodiment, bioadhesives, sutures, and / or pins can be used to secure the implant within the prostatic urethra.

[0022] It should be noted that according to the technology of the present disclosure, the implant has a fixed wire or extension to prevent the spherical end of the middle lobe from moving, meaning that the implant of the technology of the present disclosure remains permanently or semi-permanently embedded in the prostatic urethra. This is because the implant of the technology of the present disclosure does not reduce the size of the enlarged middle lobe and / or change the composition of the middle lobe, and therefore the implant must be permanently maintained in place to prevent the spherical end of the middle lobe from causing BNO. When the size of the middle lobe is reduced (e.g., by medication, surgery, or other techniques) and the spherical end of the middle lobe is no longer a concern for causing BNO, the implant of the technology of the present disclosure can be removed from the prostatic urethra. In this respect, the implant of the technology of the present disclosure can be semi-permanent.

[0023] Thus, in accordance with another embodiment of the disclosed technique, a method for deploying a prostatic urethral implant within a patient's prostatic urethra is provided. The method involves encasing the implant within a sheath. The implant is elastic, thereby conforming to a smaller circumference of the encasing sheath than the circumference of the implant when expanded. The sheath is inserted into the urethra and pushed until its distal end extends into the subject's bladder. The implant extends from the distal end of the sheath and is thus pushed within the sheath until it is released from the sheath. Upon release, the elastic implant returns to its original extended configuration due to the shape-memory material from which it is made. The implant is then retracted into the prostatic urethra and positioned in place. Positioning the implant can include its physical location within the prostatic urethra and its rotational orientation. As described below, the implant can be rotated within the prostatic urethra to properly position fixation wires in their respective positions to secure the implant to the verumontanum and apply pressure to the spherical end of the middle lobe. Once the implant is properly positioned, the sheath is removed from the urethra.

[0024] As described above, the implant can include a hollow proximal cap with a niche (or protrusion), which is non-circular and can transfer rotational motion from a corresponding pin (or corresponding niche in the case of a protrusion). Thus, the implant can be rotated within the prostatic urethra to a desired rotational orientation.

[0025] As described above, the implant is pulled back proximally from the bladder until it is positioned within the prostatic urethra (and / or bladder neck). The implant remains permanently or semi-permanently within the prostatic urethra for a period of time. During this time, the incision wire within the implant creates a longitudinal incision in the tissue surrounding the inner wall of the prostatic urethra to relieve the urethral stricture, while one of the fixation wires applies pressure to the bulbous end of the middle lobe. When the implant is to be removed from the patient, a sheath is inserted into the urethra and compresses the implant, thereby folding it back into its compressed configuration. Following this, the implant can be removed from the urethra via the sheath.

[0026] In this description, the terms pressure and force (e.g., applying radial pressure or applying radial force) are used interchangeably hereinafter to describe the action of the implant's wires on the surrounding tissue and anatomical landmarks within the prostatic urethra. That is, the wires (dissection and fixation) are described as applying pressure to the tissue or as applying an outward radial force to the tissue. Hereinafter, the terms proximal and distal refer to directions relative to the implantable device and delivery system. In particular, the distal end is the end of the device (or system) that is inserted first and reaches the deepest into the patient's body. The proximal end is the end closest to the exit from the patient's body. Thus, with respect to the technology of this disclosure, the bladder is the most distal point, while the opening of the penile urethra is the most proximal point.

[0027] Similarly, it should be noted that the technology of the present disclosure is generally described using an embodiment having two fixation wires, allowing those skilled in the art to easily understand how the description can be modified to apply the technology of the present disclosure to the other embodiments described above. This applies to embodiments having a single fixation wire with two extensions, as well as embodiments having a single fixation wire and no fixation wire to secure the implant within the prostatic urethra. In addition, while the technology of the present disclosure is described with reference to the human male reproductive system, the technology of the present disclosure (i.e., the implant and its delivery method) can be equally applied to the reproductive systems of male animals having prostates or glands anatomically and homologously similar to the human male prostate.

[0028] Reference is now made to Figures 2A, 2B, and 2C, which are schematic illustrations of a prostatic urethral implant (hereinafter referred to as the implant), generally referenced 100, for forming an incision in tissue of the inner wall of the prostatic urethra and compressing the middle lobe, constructed and operative in accordance with an embodiment of the disclosed technology. Figure 2A depicts the implant from a top-view perspective (i.e., as seen when an observer is positioned distal to the implant), while Figures 2B and 2C depict the implant from an opposite isometric perspective. Implant 100 includes three closed-form incision wires (hereinafter referred to as wires) 102A, 102B, and 102C, a first fixation wire (anti-migration fixation wire) 104, a second fixation wire (compression fixation wire) 105, a proximal cap 106, and a withdrawal string 108.

[0029] The closed configuration of each of the wires 102A-102C can be broadly divided into a proximal section 112, a distal section 114, and two lateral sections 116 extending between the proximal section 112 and the distal section 114. The proximal section 112, the distal section 114, and the lateral section 116 are numbered for only one of the wires 102A-102C to avoid clutter in FIGS. 2A-2B. As shown, the proximal section 112 can be the proximal end of a U-shape from which the lateral sections 116 extend. The distal section 114 is a section that connects the lateral sections 116. Each of the wires 102A-102C is coupled on both sides to adjacent ones of the wires 102A-102C. Thus, as shown, side section 116 of each of wires 102A-102C is coupled to a side section of an adjacent wire, shown as coupled side sections 103A, 103B, and 103C, respectively. For example, one side section of wire 102A is coupled to a side section of wire 102B as coupled side section 103B, and the other side section of wire 102A is coupled to a side section of wire 102C as coupled side section 103A. The other side section of wire 102B (not coupled to wire 102A) is coupled to the other side section of wire 102C (also not coupled to wire 102A) as coupled side section 103C.

[0030] The proximal cap 106 holds the proximal ends of the wires 102A-102C together. As shown, the proximal cap 106 has a hollow portion 107. Because the proximal cap 106 is positioned within the urethra, it must be hollow to allow urine to pass through the urethra. A withdrawal string 108 is coupled to one of the wires 102A-102C, the proximal cap 106, or both. As shown, both the first and second anchoring wires 104 and 105 have a shape resembling the outline of a leaf. The first and second anchoring wires 104 and 105 can also have a shape resembling a tip, a teardrop, or a similarly shaped profile for applying outward radial pressure. Like the proximal cap 106, the first and second anchoring wires 104 and 105 have a substantially hollow outline, thus not preventing any liquids and / or fluids from passing through the prostatic urethra in which they are positioned. The first fixation wire 104 acts as an implant anchor to secure the implant 100 within the prostatic urethra, and the second fixation wire 105 acts as a middle lobe compressor to apply pressure to the spherical end of the middle lobe and prevent it from moving around, especially after urination.

[0031] The following paragraphs describe the use of implant 100, followed by a more detailed description of the components of implant 100. Implant 100 is permanently or semi-permanently implanted into the prostatic urethra to create a longitudinal incision in the tissue of the inner wall of the prostatic urethra, thereby relieving urethral strictures and applying pressure to the bulbous end of the middle lobe to prevent BNO.

[0032] Implant 100 is implanted by employing a sheath (not shown) for inserting the implant into the urethra. Implant 100 is compressed within the sheath so that the outer diameter of implant 100 when expanded, illustrated by dotted circle 110, matches the inner diameter of the sheath. Wires 102A-102C and first and second fixed wires 104, 105 are made of an elastic material with shape memory so that they can be compressed and, upon release from the enclosing sheath, resume their original extended shape and configuration, expanding to the original outer diameter of dotted circle 110. When positioned within the prostatic urethra, the expanded diameter and configuration of implant 100 is bounded by the inner diameter of the surrounding urethral wall.

[0033] The wires 102A-102C press against the surrounding tissue (i.e., apply an outward radial force to the tissue of the prostatic urethra). Over time, the force applied by the wires 102A-102C weakens the blood (and oxygen) supply to the portion of the tissue in direct contact with the wires 102A-102C, thereby inducing tissue necrosis and forming an infarct incision. Over time, the incision becomes deeper until the wires 102A-102C reach their full expansion (i.e., until the implant 100 regains its original circumferential diameter, as illustrated by the dotted circle 110). Upon full expansion, the stricture of the prostatic urethra is substantially relieved. The first fixation wire 104 is positioned such that the distal end 113 of the first fixation wire 104 is distal to the verumontanum of the prostatic urethra. The distal end 113 substantially ensures that the implant 100 does not move and / or migrate toward the bladder after implantation. The second fixation wire 105 is positioned so that the distal end 115 of the second fixation wire 105 is distal to the spherical end of the middle lobe. The distal end 115 presses against the spherical end of the middle lobe, ensuring that the middle lobe does not move around when suction is generated in the prostatic urethra, particularly after urination.

[0034] Implant 100 is implanted so that wires 102A-102C, first fixation wire 104, and second fixation wire 105 are aligned with the longitudinal direction of the urethra. Thus, wires 102A-102C form longitudinal incisions in the tissue of the inner wall of the prostatic urethra that extend along the urinary tract.

[0035] The duration required to create an incision sufficient to relieve the urethral stricture depends on various factors, such as the level of stricture, the material of the wires 102A-102C, and the size of the wires 102A-102C in their original, fully extended configuration. As described above, the implant 100 can remain within the prostatic urethra indefinitely or for a predetermined period of time (i.e., semi-permanently). The incision created by the implant 100 forms over time without causing pain or bleeding to the patient. After the implant 100 is implanted, the patient is released and can resume their normal lifestyle without any hindrance. The pressure applied by the first and second fixation wires 104 and 105 is sufficient to maintain the position of the implant 100 within the prostatic urethra and compress the middle lobe without causing any pain and / or discomfort to the patient. Additionally, the shape of the first fixed wire 104 and the second fixed wire 105 is unobtrusive (because the shape of the fixed wires is substantially hollow), thereby allowing fluids and liquids (such as urine, prostate secretions, semen, etc.) to pass unimpeded past the first fixed wire 104 and the second fixed wire 105.

[0036] The implant 100 is implanted within the prostatic urethra to relieve urethral strictures, for example, caused by prostatic hyperplasia, and to compress the enlarged middle lobe with its bulbous end. The implant 100 can be positioned in other or additional areas of the urinary tract, such as the bladder neck. Depending on the desired placement, the lengths of the first and second fixation wires 104 and 105 may need to be altered accordingly to fulfill their respective functions of fixation and compression. Alternatively, the implant 100 can be implanted in any tubular organ requiring stricture relief while simultaneously restricting the mobility of the anatomical structure, such as a tubular organ of the digestive system, a blood vessel, or the like.

[0037] Wires 102A-102C and first and second fixation wires 104 and 105 are closed-form wires made of elastic materials. The material of all wires in the disclosed techniques (dissection and fixation) must be sufficiently elastic to allow the wires to be compressed within the sheath and conform to the inner diameter of the sheath during insertion into the urethra. The wires also require shape memory so that they regain their original extended shape and configuration (and their original outer diameter) upon release from the sheath. Additionally, the dissection wires must be strong enough to apply force to the surrounding tissue to induce tissue necrosis (e.g., 0.5 Newtons of force), thereby forming a closed longitudinal incision. The fixation wires must be strong enough to apply sufficient radial force to compress the middle lobe and verumontanum to prevent fluids and liquids from passing through the urethra and dislodging the fixation wires. Wires 102A-102C and first and second fixation wires 104 and 105 can be made, for example, from a nickel-titanium alloy (nitinol). All parts of the implant 100 must be made from biocompatible materials so that there is no risk of infection from the implant 100 to the patient's body.

[0038] As mentioned above, the closed configuration of the cutting wire can be broadly divided into three sections: a proximal section 112, a middle section consisting of lateral sections 116, and a distal section 114. The distal section 114 functions as a support cross member connecting the lateral sections 116 of the cutting wire. Exemplary closed configurations of the cutting wire are illustrated in Figures 2A-2C, 3A-3C, and 4.

[0039] The lateral sections of each of the wires 102A-102C (shown as joined lateral sections 103A-103C) are the sections that contact the tissue surrounding the prostatic urethra. That is, lateral section 116 is the section that presses against the tissue to form the incision. Each lateral section of the wires 102A-102C is joined (i.e., bonded, braided, and / or attached) to the lateral sections of an adjacent wire as described above. In this manner, the joined wires together form a supporting wire frame, with each closed-form wire forming a face of the frame and each joined pair of adjacent wire lateral sections forming an edge of the frame.

[0040] As the lateral sections of the wires 102A-102C press against the surrounding tissue (i.e., as the implant 100 attempts to resume its original shape while bounded by the inner urethral wall of the prostatic urethra), the surrounding tissue applies opposing forces to the wires 102A-102C in accordance with Newton's third law of motion. Each of the wires 102A-102C presses against the adjacent wire to which it is joined. The wire frame enhances the structural stability of the implant 100, allowing the implant 100 to apply sufficient force to form an incision in the surrounding tissue. Thus, the wire frame eliminates the need for additional support elements, such as a central support tube.

[0041] In the example depicted in FIGS. 2A-2C, the incision wires 102A-102C are joined together by being wrapped (i.e., twisted and / or braided) around each other. That is, the first side section of wire 102A and the first side section of wire 102B are wrapped around each other as combined side section 103B, the second side section of wire 102A and the first side section of wire 102C are wrapped around each other as combined side section 103A, and the second side section of wire 102B and the second side section of wire 102C are wrapped around each other as combined side section 103C. The twisted bonding of wires 102A-102C further provides structural rigidity to implant 100. Thus, each of wires 102A-102C can be thinner without compromising the robustness of implant 100. For example, each of the wires 102A-102C can be as thin as 0.5 millimeters (ie, the cross section of each wire is 0.5 millimeters).

[0042] The winding of the wires 102A-102C can be accomplished, for example, by twisting the side sections together and heat treating the implant 100 to stabilize the winding. The wires 102A-102C can be wound together by grasping the side sections and placing them in a die having rotating elements that wrap them around each other.

[0043] In the example depicted in Figures 2A-2C, there are three wound wires, each consisting of two side sections of two adjacent wires wrapped around each other. Thus, the wire frame has three side edges that form three longitudinal incisions. According to alternative embodiments of the disclosed technology, the implant may include other numbers of closed-form wires, such as a single wire, two wires (for a wire frame with two side edges that form two longitudinal incisions), four wires (for a wire frame with four side edges that form four longitudinal incisions), five wires, etc.

[0044] The proximal cap 106 is coupled to the proximal ends of the wires 102A-102C to bind the wires 102A-102C together, thereby strengthening the wire frame. In other words, the proximal cap 106 helps maintain the structure of the implant 100 (i.e., increase the structural stability) by further joining the wires 102A-102C to one another. As mentioned above, the proximal cap 106 is also hollow and has an outer diameter similar to the diameter of the unconstricted urethra, so that when positioned within the prostatic urethra, the proximal cap 106 does not exert any additional pressure on the inner wall of the urethra that could cause discomfort and / or pain to the patient.

[0045] 2A-2C, the proximal cap 106 encases the proximal ends of the wires 102A-102C. Thus, the proximal cap 106 protects the urethral tissue from becoming entangled in the proximal ends of the wires 102A-102C. Additionally, the proximal cap 106 functions to prevent the wires 102A-102C from unraveling.

[0046] The proximal cap 106 includes a hollow portion 107, which may also be described as a proximal non-circular niche (e.g., niche 402 in FIGS. 5A and 5B ). Generally, the hollow portion 107 is not circular, thus allowing the proximal cap 106 to be rotated with the aid of a tool (not shown) having a shape complementary to the hollow portion 107, thereby allowing the dissection wires 102A-102C and the first and second fixed wires 104 and 105 to be reoriented. The non-circular proximal niche of the proximal cap 106 is configured to receive a corresponding non-circular pin (i.e., a tool) and transfer the rotational movement of the pin to the implant 100. This allows a physician or user to rotate the implant 100 while it is positioned within a subject's bladder, as described in further detail below with reference to FIGS. 5A-5B and 9A-9L .

[0047] As described above, the first fixing wire 104 functions as a one-way stop, allowing the implant 100 to move from the bladder into the prostatic urethra but preventing it from moving back toward the bladder. This can be achieved by the first fixing wire 104 having a shape that is wide enough when fully expanded to hook against one of the urethral sphincters. This can also be achieved by the first fixing wire 104 applying outward radial pressure against the verumontanum of the prostatic urethra. The first fixing wire 104 can be a wire tip (e.g., as depicted in Figures 2A-2C) or any other form that allows movement across the urethral sphincter in the proximal direction while preventing movement across the urethral sphincter in the distal direction. Otherwise, the first fixing wire 104 should have a shape that provides a single directionality for its movement in the proximal direction (i.e., toward the opening of the urethra in the penis). The first fixing wire 104 can be coupled to the implant 100 elastically or via a shaft. First fixation wire 104 can also be coupled via another coupling mechanism configured to allow first fixation wire 104 to act as a one-way stop against movement across the urethral sphincter. Alternatively, another or additional fixation element can be employed to secure implant 100 in place (preventing movement in the proximal direction, the distal direction, or both), such as barbs (not shown) on wires 102A-102C. As noted above, in such an embodiment, implant 100 can include only second fixation wire 105, with the first fixation wire replaced by another mechanism to secure implant 100 within the prostatic urethra and prevent it from migrating toward the bladder.

[0048] The second fixation wire 105 functions to apply pressure to the bulbous end of the middle lobe, thereby preventing the bulbous end from moving towards the bladder neck after urination.

[0049] The withdrawal string (hereinafter referred to as the string) 108 allows the physician to withdraw the implant 100. Specifically, the distal end of the string 108 is coupled to the implant 100, and the proximal end of the string 108 extends (slightly) outside the patient's body. The physician can insert a withdrawal sheath into the urethra along the string 108 to wrap and compress the implant 100. The physician can withdraw the wrapped implant by pulling the string 108. The string 108 is strong enough to pull the implant 100 without tearing (e.g., the thickness and material of the string 108 allow the implant 100 to be pulled via the string 108). The string 108 may be a single strand or a woven bundle of strands to further strengthen it. As described below, a withdrawal sheath is inserted into the urethra via the string 108 and guided over the implant 100. By pulling on string 108, implant 100 is then pulled into the retraction sheath and compressed into a shape that fits within the retraction sheath, as it was when implant 100 was initially deployed. The retraction sheath, with implant 100 compressed within it, can then be removed by pulling on string 108 and the retraction sheath.

[0050] Implant 100 is deployed so that it does not extend distally beyond the subject's bladder neck (i.e., it does not extend into the bladder). Specifically, wires 102A-102C do not contact the tissue of the bladder itself. As a result, implant 100 does not irritate the patient's bladder.

[0051] According to one embodiment of the disclosed technology, the wires of the implant 100 can be colored to facilitate positioning by a physician when deployed within the prostatic urethra. For example, the incision wires of the implant 100 can be color-coded so that the section to be positioned above the prostatic urethra is colored blue and the section to be positioned below the prostatic urethra is colored white. The physician can observe the implant 100 in the bladder through a cystoscope and rotate the implant 100 to the desired orientation according to the color of the implant 100. Similarly, the first and second fixation wires 104 and 105 can be color-coded to ensure proper positioning distal to the verumontanum and distal to the spherical end of the middle lobe, respectively. As just mentioned, using a cystoscope, the physician can also observe and verify the position of the fixation wires to ensure proper placement.

[0052] Reference is now made to FIGS. 3A, 3B, and 3C, which are schematic illustrations of a second prostatic urethral implant, generally referenced 200, for forming an incision in tissue of the inner wall of the prostatic urethra, constructed and operative in accordance with another embodiment of the disclosed technology. FIG. 3A depicts the implant from an isometric perspective, FIG. 3B depicts the implant from a top view perspective, and FIG. 3C depicts one of the implant's closed-shape wires. The second implant 200 is substantially similar to the implant 100 (FIGS. 2A-2C), except that the second implant 200 does not include a proximal cap and the lateral sections of the incision wires are joined together without being wrapped together, as described below. The implant 200 includes three closed-shape incision wires 202A, 202B, and 202C, a first fixation wire (anti-migration fixation wire) 204, and a second fixation wire (compression fixation wire) 206. The proximal end of implant 200 is indicated by arrow 208. The components of implant 200 are similar to the components of implant 100, and therefore, for the sake of brevity, only the differences will be detailed hereinafter.

[0053] The closed configuration of each of the wires 202A-202C is depicted in Figure 3C. The closed configuration is truncated at its distal end. Thus, the distal end of each of the wires 202A-202C is substantially perpendicular to the longitudinal axis of the implant 200. Therefore, the cutting wires do not contact bladder tissue, thus preventing bladder irritation.

[0054] As shown, the wires 202A-C are not wrapped around one another. Instead, the wires 202A-C can be joined together in various ways (i.e., the side sections are joined to the side sections of adjacent wires). For example, the incision wires can be welded together, glued together, or joined by a connecting mechanism or element (e.g., a connecting thread that binds the side sections together).

[0055] In the example depicted in Figures 3A-3C (and Figure 4 herein below), the implant 200 is shown without a proximal cap and withdrawal string. However, it should be noted that the implant 200 can include either a proximal cap, a withdrawal string, or both. The relative positioning of the first and second securing wires 204, 206 is also shown. As shown, the first securing wire 204 is shorter than the second securing wire 206. The proximal ends of the incision wires 202A-202C and the first and second securing wires 204 and 206 are all bonded together at the proximal end 208 of the implant 200. The wires 202A-202C and the first and second securing wires 204 and 206 can be bonded via welding, adhesive, bonding thread, etc.

[0056] Reference is now made to FIG. 4, which is a schematic illustration of a third prostatic urethral implant, generally referenced 300, for forming an incision in tissue of the inner wall of the prostatic urethra, constructed and operative in accordance with a further embodiment of the disclosed technology. Implant 300 includes three closed-shape incision wires 302A, 302B, and 302C, a first fixation wire (a fixation wire for preventing migration) 304, and a second fixation wire (a fixation wire for compression) 306. The components of implant 300 are similar to those of implant 200 (FIGS. 3A-3C), and for the sake of brevity, only the differences will be detailed hereinafter. Implant 300 is depicted from a bottom-view perspective (i.e., as seen by a proximal observer). The closed shape of wires 302A-302C is triangular, whereby wires 302A-302C together form a triangular pyramid wire frame, with the proximal ends of the wires forming the apex of the pyramid indicated by arrow 310 and the distal ends forming the base of the pyramid. As shown and numbered for incision wire 302A, its lateral sections 308A and 308B are joined to adjacent lateral sections (unnumbered) of incision wires 302B and 302C. The joined lateral sections of wires 302A-302C form the lateral edges of the triangular pyramid. As will be appreciated by those skilled in the art, other wire frame shapes are possible for the prostatic urethral implants of the disclosed technology, such as square-based pyramids, pentagonal-based pyramids, polygonal-based pyramids, etc.

[0057] Reference is now made to FIGS. 5A and 5B, which are schematic illustrations of proximal niches, generally referenced 402 and 404, respectively, of a proximal cap of a prostatic urethral implant constructed and operative in accordance with yet another embodiment of the disclosed technology. FIGS. 5A and 5B illustrate a proximal cap 400 substantially similar to proximal cap 106 (FIGS. 2A-2C). As shown, the proximal niche has a hollow, non-circular shape to allow for the transfer of rotational motion to the implant from a corresponding pin or tool (not shown) inserted into the niche. The hollow shape allows for the flow of liquids and fluids through the proximal cap. Thus, a physician can rotate the implant from a position outside the patient, even if the implant has already been inserted into the urethra (e.g., the implant is in the bladder). In the example depicted in FIG. 5A, niche 402 is rectangular in shape, and in the example depicted in FIG. 5B, niche 404 is hexagonal in shape. Alternatively, the proximal niche can have any shape that allows for transmitting rotational motion (i.e., rotation around the central axis (unsigned) of the proximal cap), such as a non-circular shape, a slit, an array of niches (e.g., two holes), etc.

[0058] Reference is now made to FIGS. 6A and 6B, which are schematic illustrations of a fourth prostatic urethral implant, generally referenced 450, for forming an incision in tissue of the inner wall of the prostatic urethra, constructed and operative in accordance with yet further embodiments of the disclosed technology. FIG. 6A depicts the implant from a top view perspective (i.e., as seen when an observer is positioned distal to the implant), and FIG. 6B depicts the implant from an isometric perspective. Implant 450 includes three closed-shaped incision wires 454A, 454B, and 454C, a bifurcated fixation wire (compression fixation wire) 458, and a proximal cap 452. Implant 450 is substantially similar to implants 100 ( FIGS. 2A-2C ), 200 ( FIGS. 3A-3C ), and 300 ( FIG. 4 ). Proximal cap 452 includes a hollow portion 455, and as shown, the lateral sections of each two adjacent incision wires are joined together, as shown as lateral sections 456AB (joining the lateral sections of wires 454A and 454B), 456BC (joining the lateral sections of wires 454B and 454C), and 456AC (joining the lateral sections of wires 454A and 454C). For brevity, only the differences between implant 450 and implants 100, 200, and 300 will be detailed.

[0059] As can be seen, implant 450 includes a single fixation wire, labeled as bifurcated fixation wire 458, that includes first extension 460A and second extension 460B. Bifurcated fixation wire 458 is functionally equivalent to first fixation wire 104 ( FIGS. 2A-2C ) and second fixation wire 105 ( FIGS. 2A-2C ), with first extension 460A functionally similar to second fixation wire 105 and second extension 460B functionally similar to first fixation wire 104. Thus, first extension 460A functions as a middle lobe constrictor, while second extension 460B functions as an anchor with the verumontanum to prevent implant 450 from migrating toward the bladder after implantation. Alternatively, bifurcated fixation wire 458 is a monolithic fixation wire with two extensions, one for securing the implant to the verumontanum and the other for compressing the middle lobe. Like first and second fixation wires 104 and 105, bifurcated fixation wire 458 can be made from an elastic material with shape memory, such as Nitinol. Thus, the primary difference in this embodiment is that the fixation wire is a single wire attached to proximal cap 452, rather than two separate fixation wires attached to the proximal cap, as shown, for example, in FIGS. 2A-2C. The bifurcated fixation wire 458 (i.e., as a single fixation wire) configuration can also be used with the wire frame shapes and configurations of implants 200 (FIGS. 3A-3C) and 300 (FIG. 4).

[0060] Reference is now made to FIG. 7, which is a schematic illustration of a fifth prostatic urethral implant, generally referenced 470, for forming an incision in tissue of the inner wall of the prostatic urethra, constructed and operative in accordance with yet another embodiment of the disclosed technology. FIG. 7 depicts the implant from a top view perspective (i.e., as seen when an observer is positioned distal to the implant). Implant 470 includes three closed-shaped incision wires 504A, 504B, and 504C, a fixation wire (compression fixation wire) 480, and a proximal cap 502. Implant 470 is substantially similar to implants 100 (FIGS. 2A-2C), 200 (FIGS. 3A-3C), 300 (FIG. 4), and 450 (FIGS. 6A-6B). A main body 476 of proximal cap 502 is shown. As with other implants of the disclosed technology, the lateral sections of each two adjacent incision wires are joined together (unnumbered). For the sake of brevity, only the differences between implant 470 and implants 100, 200, 300 and 450 will be detailed.

[0061] As can be seen, the implant 470 includes only a single fixation wire, functionally similar to the second fixation wire 105 (FIGS. 2A-2C), thereby performing the function of compressing the middle lobe. Therefore, the implant 470 does not include a fixation wire to prevent its migration toward the bladder. Instead of a fixation wire for that purpose, the body 476 includes multiple barbs 478 (as an example) to hold the proximal cap 502 within the prostatic urethra. The multiple barbs 478 prevent the implant 470 from migrating toward the bladder. When a sheath is placed over the implant 470, the multiple barbs 478 are covered and do not come into contact with the tissue of the inner wall of the urethra. Thus, the implant 470 can be inserted and retracted from the urethra using a sheath (not shown) that covers the multiple barbs 478 and prevents abrasion of the multiple barbs 478 against the tissue of the inner wall of the urethra. As described above, other mechanisms (instead of the multiple barbs 478) can be used to secure the position of the implant 470 to prevent migration toward the bladder after implantation.

[0062] Reference is now made to FIG. 8, which is a schematic diagram illustrating the placement of a prostatic urethral implant, generally referenced 550, within a prostatic urethra, constructed and operative in accordance with yet a further embodiment of the disclosed technology. FIG. 8 illustrates a sagittal cross-section of a prostatic urethra with an implant 566 of the disclosed technology (e.g., substantially similar to implant 100 of FIG. 2A ) positioned therein. Shown is a urethra 552 entering a prostate gland 554 having a posterior lobe (not shown), lateral lobes 556, a middle lobe 558, and an anterior lobe (not shown). An ejaculatory duct 562 enters the prostate gland 554 between the posterior lobe and the middle lobe 558. The middle lobe 558 is enlarged, thereby presenting a bulbous, pendulous end 564. The verumontanum 572 of the prostatic urethra is also shown, along with the bladder 560.

[0063] The implant 566 includes multiple incision wires, shown diagrammatically as incision wires 570, a first fixed wire 574, a second fixed wire 576, and a proximal cap 568. When implanted, the proximal cap 568 seats proximally within the prostatic urethra at the opposite end from the bladder neck (not shown), as shown. The incision wires 570 seat within the prostatic urethra and apply an outward radial force along the tissue of the inner wall of the prostatic urethra. As described above, this force creates incisions in the inner wall of the prostatic urethra, resulting in infarction and relieving constriction pressure from the lateral lobes 556 of the prostate. The first fixation wire 574 is long enough to apply pressure to the verumontanum 572 by exerting an outward radial force, indicated by arrow 578B, while the second fixation wire 576 is even longer than the first fixation wire 574 and exerts an outward radial force, indicated by arrow 578A, on the spherical end 564. Radial force 578B is sufficient to prevent the implant 566 from migrating toward the bladder neck, and radial force 578A is sufficient to prevent the spherical end 564 from moving around, especially after urination, which could cause the spherical end to be sucked toward the bladder neck and cause BNO. The proximal cap 568 is hollow, thus allowing fluids and liquids to pass therethrough. As described above, the implant 566 is either permanent or semi-permanent and remains within the prostatic urethra.

[0064] Reference is now made to FIGS. 9A-9L, which are schematic illustrations of a method for deploying and withdrawing a prostatic urethral implant operable in accordance with yet another embodiment of the disclosed technology. Referring to FIG. 9A, a prostatic urethral implant 500 of the disclosed technology is shown along with a deployment sheath 502 and a guidewire 506. The implant 500 includes a proximal cap (both not shown) having a non-circular proximal niche. The guidewire 506 includes a distal head (i.e., a distal pin) whose shape corresponds to the shape of the non-circular proximal niche of the proximal cap of the implant 500. The guidewire 506 also includes an inner channel (not shown). The distal head of the guidewire 506 is inserted into the non-circular proximal niche of the proximal cap of the implant 500. The implant 500 is attached to the distal end of the deployment sheath 502 such that the guidewire 506 extends through the deployment sheath 502.

[0065] Referring to Figure 9B, the physician removes the protective cover 504 from the implant 500, thereby expanding the implant 500 to its expanded, open configuration (as seen in any of Figures 2A-2C, 3A-3C, 4, 6A-6B, and 7). The protective cover 504 keeps the implant 500 sterile during storage prior to use. Referring to Figure 9C, while holding the guidewire 506, the physician pushes the deployment sheath 502 over the implant 500, thereby encasing (and thus compressing) the implant 500 within the deployment sheath 502 for delivery into the urethra.

[0066] Referring to FIG. 9D, a physician inserts a rigid cystoscope 508 (e.g., size 20 French) into the urethra 509, as in conventional urethral catheterization, until its distal end enters the bladder 511. Referring to FIG. 9E, the physician inserts the deployment sheath 502, including the compressed implant 500 positioned within the deployment sheath 502, into the cystoscope 508. The physician continues to push the implant 500 through the cystoscope 508 by pushing the guidewire 506 until the implant 500 extends through the distal end of the cystoscope 508. Referring to FIG. 9F, the physician removes the sheath 502 from the implant 500 and removes it from the cystoscope 508. This action essentially releases the implant 500 so that it can expand to its open configuration. Referring to FIG. 9G, upon release from the deployment sheath 502 and the cystoscope 508, the implant 500 expands (i.e., resumes its original extended shape). In FIG. 9G, a first fixed wire 514 and a second fixed wire 516 are shown.

[0067] Referring to FIG. 9H, the physician rotates the implant 500 to the desired orientation by rotating the guide wire 506 (with its distal head inserted into the proximal niche of the implant 500) as indicated by arrow 518. The first and second fixation wires 514 and 516 of the implant 500 (e.g., the first and second fixation wires 104 and 105 in FIGS. 2A-2C ) should be positioned accordingly to overlie the spherical ends of the verumontanum and middle lobe (both unlabeled). The wires (dissection wires and / or fixation wires) of the implant 500 can be color-coded, such that the section to be positioned superiorly is colored, for example, blue, and the section to be positioned inferiorly is colored, for example, white. The physician uses the proximal cap to rotate the implant 500 as detailed above.

[0068] Referring to FIG. 9I, while holding the implant 500 in place using the guidewire 506, the physician retracts the cystoscope 508. The physician then pulls the implant 500 over the guidewire 506 until the first and second fixation wires 514, 516 of the implant 500 slide across the internal urethral sphincter. The physician continues to pull the implant 500 over the guidewire 506 into the prostatic urethra until the first fixation wire 514 is positioned across the verumontanum and the second fixation wire 516 is positioned across the bulbous end of the middle lobe. The implant 500 is now positioned accordingly within the prostatic urethra. Referring to FIG. 9J, if the implant 500 includes a withdrawal string 510, the physician cuts the knot 512 at the proximal end of the withdrawal string 510 and retracts the guidewire 506 from the urethra.

[0069] The implant 500 is then implanted into the prostatic urethra and begins to apply a radially outward force to the surrounding tissue of the inner wall of the prostatic urethra to form a longitudinal incision. In addition, the second fixation wire 516 compresses the spherical end of the middle lobe, holding it in place. The implant 500 can be left permanently or semi-permanently within the prostatic urethra. If desired, the implant 500 can be removed, as described in more detail below.

[0070] Referring to FIG. 9K, to remove the implant 500, the physician inserts the cystoscope 508 through the urethra toward the bladder 511, over the withdrawal string 510, toward the implant 500. Alternatively, the physician can insert the deployment sheath 502 into the urethra instead of the cystoscope 508. The physician pushes the cystoscope 508 (and / or deployment sheath 502) until it encases and compresses the implant 500. The implant 500 is then positioned within the cystoscope 508 and / or deployment sheath 502. Referring to FIG. 9L, the physician can then withdraw the implant 500 encased within the cystoscope 508 by pulling the implant 500 via the withdrawal string 510. Alternatively, the physician can insert a tool (not shown) into the deployment sheath 502 to pull and remove the implant 500. The physician then withdraws the cystoscope 508 and / or deployment sheath 502 from the urethra.

[0071] It will be appreciated by persons skilled in the art that the technology of the present disclosure is not limited to what has been particularly shown and described above. Rather, the scope of the technology of the present disclosure is defined only by the following claims. [Explanation of symbols]

[0072] 100,200,300,450,470,500,566 Implants 102A~102C, 202A~202C, 302A~302C, 454A~454C, 504A~504C, 570 Wire 104,204,304,514,574 First fixed wire 105,206,306,516,576 Second fixed wire 106,400,452,502,568 Proximal Cap 107 Hollow part 108 Drawer string 110 yen 112 Proximal Section 113 Distal end 114 Distal Section 103A~103C, 116, 308A, 308B, 456AB, 456BC, 456AC Side sections 208,518,578A,578B Arrows 402,404 niches 455 Hollow part 458 Fixed Wire 460A First Extension 460B Second extension 476 Main Unit 478 Return 480 Fixed Wire 502 Deployable Sheath 504 Protective Cover 506 Guidewire 508 Cystoscope 510 Drawer string 511 Bladder 512 knots 552 Urethra 554 Prostate 556 Lateral lobe 558 Nakaha 560 Bladder 562 Ejaculatory duct 564 edge 572 Verumontanum

Claims

1. 1. A prostatic urethral implant for creating an incision in a patient's prostatic urethra and compressing a middle lobe of the prostate, comprising: at least two incision wires in a closed configuration, each of the at least two incision wires having a proximal section, a distal section, and side sections extending longitudinally between the proximal and distal sections, each of the side sections being joined to another side section; a compression fixation wire in a closed configuration extending outward from at least one of the proximal sections through one of the incision wires and compressing the middle lobe when the prostatic urethral implant is positioned within the prostatic urethra; each of the at least two incision wires and the compression fixation wire is elastic and has shape memory, thereby being capable of having an expanded configuration and a compressed configuration; a prostatic urethral implant, wherein in the expanded configuration, the at least two dissection wires dissect tissue within the prostatic urethra via outward radial pressure and the compression fixation wire applies outward radial pressure to the middle lobe.

2. 2. The prostatic urethral implant of claim 1, wherein each of the lateral sections of each of the at least two cutting wires is wrapped around another lateral section of another of the at least two cutting wires.

3. The prostatic urethral implant of claim 1 , wherein each of the lateral sections of each of the at least two incision wires are joined together via a bonding technique.

4. The bonding technique comprises: Adhesion, welding, and using a binding thread to bind the side sections together; 4. The prostatic urethral implant of claim 3 selected from the list consisting of:

5. 10. The prostatic urethral implant of claim 1, further comprising a hollow proximal cap coupled to the proximal section of each of the at least two incision wires and the compression fixation wire, the hollow proximal cap configured to hold the at least two incision wires and the compression fixation wire together.

6. the hollow proximal cap includes a proximal non-circular niche configured to receive a corresponding feature; The prostatic urethral implant of claim 5 , wherein the proximal non-circular niche is configured to transfer rotational movement of the corresponding mechanism to the implant.

7. The corresponding mechanism is pins, and tool, 7. The prostatic urethral implant of claim 6, selected from the list consisting of:

8. 10. The prostatic urethral implant of claim 1, further comprising a withdrawal string coupled to the implant, the withdrawal string positioned to allow the implant to be withdrawn from the patient.

9. The at least two incision wires and the compression fixation wire are Nickel-titanium alloy (Nitinol), and biocompatible materials, 10. The prostatic urethral implant of claim 1, made from a material selected from the list consisting of:

10. 10. The prostatic urethral implant of claim 1, further comprising an anti-migration fixation wire that is shorter than the compression fixation wire and that prevents the implant from moving distally toward the patient's bladder neck after implantation.

11. the compression fixation wire comprises at least two extensions, a first extension of the at least two extensions for compressing the middle lobe, and a second extension of the at least two extensions for preventing the implant from moving distally toward the patient's bladder neck after implantation; 10. The prostatic urethral implant of claim 1, wherein the first extension of the at least two extensions is longer than the second extension of the at least two extensions.

12. The prostatic urethral implant of claim 5 , wherein the hollow proximal cap further comprises a plurality of barbs.

13. 10. The prostatic urethral implant of claim 1, wherein the at least two incision wires diverge at their respective distal sections such that the distal sections form a simple closed curve shape at the end of the implant in the expanded configuration.

14. The simple closed curve shape is triangle, square, pentagon, and polygon, 14. The prostatic urethral implant of claim 13 selected from the list consisting of:

Images