An implantable biocompatible expander for treating body cavity contraction

Abstract

An implantable biocompatible dilator (1) suitable for implantation in a urinary tract includes: an elongated sinusoidal ring having at least two proximal forks (7) and at least two distal forks (5), wherein the dilator can elastically deform from a relaxed radial expansion orientation to a radial contraction orientation, the radial contraction orientation being suitable for transluminal delivery through the urinary tract. The dilator is configured to apply radially outward forces to the urinary tract wall when in situ within the urinary tract. In particular, the dilator is suitable for treating benign prostatic hyperplasia and can be configured to be implanted and substantially cross the prostatic urethra between the bladder neck and the external sphincter.

Description

[0001] Divisional application

[0002] This application is a divisional application of application number 2016800785042, filed on November 14, 2016, and entitled "An implantable biocompatible expander for treating body cavity contraction." Background Art

[0003] Benign prostatic hyperplasia (BPH) involves the proliferation of prostatic stroma and epithelial cells, resulting in the formation of large discrete nodules in the prostate transition zone. When the nodule is large enough, it invades the prostatic urethra and increases the resistance of urine flow from the bladder, causing discomfort to the patient. The obstructed urine flow forces the bladder to work harder during urination, resulting in progressive hypertrophy and instability and weakness of the bladder muscle. There are a variety of treatment methods for benign prostatic hyperplasia to choose from, including drug therapy (such as alpha blockers and 5-reductase inhibitors), clean intermittent self-catheterization, surgery and minimally invasive treatment, such as transurethral microwave thermotherapy and transurethral puncture. Another treatment method is to implant a dilator in the prostatic urethra. Such a dilator described in US5269802 patent is provided with two coplanar rings, and the coplanar structure is maintained by three pillars. In use, the larger of the two rings is placed in the bladder, and the smaller one is placed in the bladder urethra. The prostate dilator can immediately relieve the symptoms of benign prostatic hyperplasia, but due to the high rate of adverse reactions, this method has been eliminated. These dilators typically have an elongated cylindrical shape, similar to traditional dilators used in cardiovascular or peripheral vascular disease. They may migrate from their site of insertion into the bladder or membranous urethra (up to 12.5% ​​of patients), cause crust formation and obstruct the urethra (up to 27.5%), and cause urinary incontinence (up to 3%) and pain. Cases of severe inflammatory reactions to prostate dilators have been reported, resulting in removal in a total of 8% to 47% of prostate dilators in the past. In addition, previous prostate dilators were not designed to accommodate the unique characteristics of the prostatic urethra.

[0004] WO2015 / 138763 describes a urethral dilator configured to be implanted in the prostatic urethra and dilate in situ, comprising a plurality of spaced and interconnected circular rings. This device has several disadvantages: increased crusting due to the circular arrangement of the rings (meaning that they meet the urine stream at a 90° angle); difficulty in removing the rings due to their implantation at a 90° angle to the longitudinal axis of the urethra; the rings obstruct the spermatic cord and may partially block the ejaculatory and prostatic ducts; the rigidity and immobility of the rings obstruct the natural movement of the prostate during urination and ejaculation, causing pain; and the spacing of the rings results in discontinuous expansion along the prostatic urethra.

[0005] The object of the present invention is to overcome at least one of the above technical problems. Summary of the invention

[0006] In a broad sense, the present invention provides an elastically deformable dilator, which, in one embodiment, is suitable for treating benign prostatic hyperplasia (BPH). The dilator takes the form of a single elongated corrugated ring, which is configured to be implanted in a target location in a body cavity, which is contracted due to adjacent diseased tissue. The corrugated ring has at least two distal forks and at least two proximal forks, and the distal forks and the proximal forks are generally configured to be sunken into the wall of the body cavity. The dilator is generally elastically deformable in a radial direction between a contracted orientation and an expanded (expanded) orientation, the contracted orientation being suitable for transluminal delivery through the body cavity to a target site, and the expanded (expanded) orientation being configured to achieve in situ expansion of the body cavity at the target site. The structure of the elongated corrugated ring minimizes the contact area between the dilator and the body cavity wall, thereby reducing the degree of possible crusting. In addition, the pillars of the corrugated ring extend mainly in the longitudinal direction (rather than the circumferential direction) due to the elongated corrugated ring shape, thereby ensuring that the fluid flows along, rather than perpendicular to, the pillars on the exposed surface of the pillars. This further reduces the probability of crusting. The substantially longitudinal distribution of the struts also facilitates removal of the dilator. Furthermore, the structure of the dilator's corrugated ring allows it to bend differently during use, thereby allowing its shape to conform to the anatomical shape, fit the body cavity wall, and move with it. In particular, the dilator of the present invention does not obstruct the verumontanum and the ejaculatory duct, and its three proximal forks are anatomically located in the triangular-shaped distal urethra, reducing the possibility of dilator movement (and facilitating removal). The corrugated ring structure also ensures that it expands in the correct urethral anatomical area (especially the transition area that presses the prostate).

[0007] The dilator of the present invention provides a device for dilating a body cavity that has contracted due to, for example, a morbidity or trauma. An example of a morbidity is benign prostatic hyperplasia. The disease is a diffuse disease that can cause the prostate to tighten around the prostatic urethra and partially block it. Therefore, in one embodiment, the present invention provides an elastically deformable dilator that can be used to treat benign prostatic hyperplasia (BPH), wherein the dilator is in the form of a waveform (preferably, a sinusoidal) ring that is configured to be implantable inside the prostatic urethra between the bladder neck and the external sphincter, and in one embodiment, it generally spans the prostatic urethra between the bladder neck and the external sphincter. In this embodiment, the waveform ring preferably has at least three distal forks and at least three proximal forks, and the distal forks and proximal forks are appropriately configured to be trapped in the wall of the prostatic urethra, and ideally, can be elastically deformed from a relaxed radial expansion orientation to a radial contraction orientation, which is suitable for delivery to a target area through the urethra, and after being in place, causes the prostatic urethra to expand, allowing urine to pass freely through the prostatic urethra, thereby alleviating a symptom of benign prostatic hyperplasia. In addition, the wavy ring structure of the dilator minimizes the contact area between the dilator and the prostatic urethra wall, thereby greatly reducing the risk of the dilator blocking the ejaculatory duct and also reducing the formation of crusts. Since the triangular cross-sectional shape of the dilator matches the triangular cross-sectional shape of the prostatic urethra (each prong falls into the lateral triangular groove in the urethra), the wavy ring structure also allows the proximal stent to be stabilized in the distal urethra. Further, the wavy ring structure of the dilator allows the dilator to bend differently during use, thereby allowing the dilator to adhere to the bladder urethra wall and move with it when subjected to various external forces during urination and ejaculation (for example, expansion of the urethra during urination and contraction / spasm of the bladder neck and distal urethra / external sphincter during ejaculation). The location of the prongs in the triangular grooves also allows the urethral wall to move normally during contraction.

[0008] Accordingly, in a first aspect, the present invention provides an implantable dilator suitable for implantation in a body cavity and expansion of a contracted segment of the body cavity, the dilator comprising a corrugated ring which is generally elongated and comprises at least two distal fork-shaped portions and at least two proximal fork-shaped portions, wherein the dilator is generally elastically deformable from a radially contracted orientation and ideally self-expandable to a radially expanded orientation, wherein the dilator is constructed to be able to span a substantial portion of the contracted segment within the body cavity and to be able to cause expansion of a substantial portion of the contracted segment within the body cavity after being in place.

[0009] The implantable biocompatible dilator of the present invention is suitable for treating contractions of various body cavities, including the urinary tract (e.g., urethra or ureter), esophagus, and gastrointestinal tract. The causes of contraction can be various, including benign and malignant diffuse disorders of nearby tissues. In a preferred embodiment, the dilator is configured for use in the urinary tract, for example, to dilate a urinary tract that has contracted due to growth within the urinary tract, or growth of adjacent tissues.

[0010] In one embodiment, the present invention provides an implantable biocompatible dilator suitable for implantation in a urinary tract and dilating a contracted section of the urinary tract, the dilator comprising an elongated wavy ring comprising at least two proximal forks and at least two distal forks, wherein the dilator is elastically deformable from a radially contracted orientation and self-expandable to a radially expanded orientation, the radially contracted orientation being suitable for transluminal delivery through the urinary tract, wherein the dilator is constructed to span a substantial portion of the contracted section within the urinary tract and is capable of dilating a substantial portion of the contracted section within the urinary tract after being in place.

[0011] The dilator of the present invention is particularly suitable for treating benign prostatic hyperplasia (BPH). Thus, in one embodiment, the present invention provides an implantable biocompatible dilator suitable for treating benign prostatic hyperplasia, wherein the dilator is configured for implantation within the prostatic urethra between the bladder neck and the external sphincter, spanning a substantial portion of the prostatic urethra between the bladder neck and the external sphincter, wherein the dilator is elastically deformable from a radially contracted orientation and self-expandable to a radially expanded orientation, the radially contracted orientation being suitable for transluminal delivery through the urethra.

[0012] Preferably, the distal prong and / or the proximal prong are configured to sink into the wall of the prostatic urethra.

[0013] In one embodiment, the elongated wavy ring includes at least three proximal prongs and at least three distal prongs.

[0014] In one embodiment, the elongated wavy ring includes three or five distal prongs and three or five proximal prongs.

[0015] In one embodiment, the elongated wavy ring includes three distal prongs and three proximal prongs. When the condition to be treated is benign prostatic hyperplasia, the use of three distal and proximal prongs is ideal because the dilator will have a generally triangular cross-section that matches the cross-section of the prostatic urethra.

[0016] In one embodiment, the elongated wavy ring includes five distal prongs and five proximal prongs.

[0017] In one embodiment, the wave ring includes seven distal prongs and seven proximal prongs.

[0018] In one embodiment, the wave loop is a sinusoidal loop.

[0019] The long wave ring generally includes an elongated strut connecting the distal fork and the proximal fork and an open area between the strut and the fork. The radially outward surfaces of the fork and the strut are suitably less than 10% of the total open area. The radially outward surfaces of the fork and the strut are suitably less than 7% of the total open area. The radially outward surfaces of the fork and the strut are suitably less than 5% of the total open area. The radially outward surfaces of the fork and the strut are suitably less than 3% of the total open area.

[0020] In one embodiment, the fork is substantially V-shaped. In another embodiment, the fork is substantially U-shaped. In another embodiment, the fork is substantially rectangular.

[0021] In one embodiment, the elongated struts of each fork are substantially straight. In another embodiment, the elongated struts of each fork are substantially curved. In one embodiment, the elongated struts of each fork are substantially curved outward. In one embodiment, the elongated struts of each fork are substantially curved outward. In one embodiment, at least one elongated strut is substantially curved outward and at least one elongated strut is substantially curved inward.

[0022] In one embodiment of the invention, the apex of one or more of the prongs includes a ring or lip. Typically, the ring or lip extends radially into the dilator (i.e., the ends of the prongs flare inwardly). In another embodiment, the ring or lip extends radially out of the dilator (i.e., the ends of the prongs flare inwardly).

[0023] In one embodiment, the vertices of the distal forks are not connected in a circumferential direction. In one embodiment, the vertices of the proximal forks are not connected in a circumferential direction.

[0024] In one embodiment, the prongs are longitudinally staggered with each other. In one embodiment, the prongs are longitudinally staggered with each other at the distal end of the dilator. In another embodiment, the prongs are longitudinally staggered with each other at the proximal end of the dilator. In another embodiment, the prongs are longitudinally staggered with each other at both the distal and proximal ends of the dilator.

[0025] In one embodiment, the apex of the distal prongs includes a ring or lip that extends generally radially into the dilator, and the apex of the proximal prongs includes a ring or lip that extends generally radially from the dilator. In another embodiment, the apex of the distal prongs includes a ring or lip that extends generally radially from the dilator, and the apex of the proximal prongs includes a ring or lip that extends generally radially into the dilator.

[0026] In one embodiment of the present invention, the apex of one or more of the forks is substantially M-shaped.

[0027] In one embodiment, the expander is formed by a wire (e.g., a nickel-titanium alloy wire). The wire can have any shape, such as circular, oval, rectangular, square or other. In a preferred embodiment, the shape of the wire is circular. The expander can also be formed by a strip, and it can be formed by any process, such as cutting from a tubular structure. In a preferred embodiment, the expander is formed by laser cutting. In one embodiment, the expander includes an anchoring element for anchoring the expander in situ in a body cavity. In one embodiment, the expander includes at least two anchoring elements. In one embodiment, the at least two anchoring elements protrude in different directions. In one embodiment, the expander includes at least one anchoring element arranged at the proximal end of the expander and at least one anchoring element arranged at the distal end of the expander. In one embodiment, the anchoring element includes a protrusion, such as a hook, a barb, a coil or a screw. In one embodiment of the present invention, the wave ring or the sinusoidal ring includes a single wire, the ends of which are usually connected at or near each end. In one embodiment of the present invention, one of the ends of the wire is formed as an anchoring element. In one embodiment of the invention, the anchoring element comprises an end of the thread that extends beyond the connection point. In one embodiment of the invention, each end of the thread extends beyond the connection point, typically coextensive with the struts of the expander. In one embodiment, the anchoring element or each anchoring element or at least a portion thereof is biodegradable. This allows the anchoring element (or a portion thereof) to biodegrade over time, thereby being easily removed after the anchoring element degrades.

[0028] In one embodiment, the anchoring element comprises a collar configured to surround the strut and one or more protrusions extending from the collar. In one embodiment, the protrusions are disposed on each end of the collar. In one embodiment, the protrusions are disposed on opposite sides of the collar. In one embodiment, the or each protrusion is a barb.

[0029] In one embodiment, the elongated sinusoidal ring is cylindrical, conical, frusto-conical, tapers inwardly at each end (ie, barrel-shaped), or tapers inwardly toward a mid-section (ie, has a waisted shape).

[0030] In one embodiment, the dilator is suitable for eluting a pharmaceutically active agent. Examples of pharmaceutically active agents include tissue growth inhibitors such as alpha reductase inhibitors or cell proliferation inhibitors such as paclitaxel. Methods of incorporating drugs into dilators for in vivo elution will be apparent to those skilled in the art and are described in, for example, US5591277, US5697967, US5599325, US2007 / 0077266, WO0112779, and WO9013332.

[0031] In another aspect, the present invention provides an implantable biocompatible dilator for treating benign prostatic hyperplasia, wherein the dilator:

[0032] being configured for elastic deformation and self-expansion from a radially contracted orientation suitable for transluminal delivery through the urinary tract, particularly through the urethra, to a radially expanded orientation capable of achieving in situ expansion of the prostatic urethra;

[0033] It is usually constructed to be able to be installed in the prostatic urethra between the bladder neck and the external sphincter without obstructing the seminal vesicles;

[0034] It is typically configured to anatomically conform to the prostatic urethra wall; and typically includes multiple longitudinal struts and typically no circumferential struts.

[0035] In another aspect, the present invention provides an elongated indwelling dilator ring for treating benign prostatic hyperplasia, the dilator ring being configured to be installed in the prostatic urethra between the bladder neck and the external sphincter without obstructing the verumontanum and achieving in situ dilation of the prostatic urethra.

[0036] In another aspect, the present invention provides an elongated indwelling dilator ring for treating benign prostatic hyperplasia, the dilator ring comprising a plurality of longitudinal struts and generally no circumferential struts, and configured such that when expanded the dilator conforms to the anatomy of the prostatic urethra without obstructing the verumontanum.

[0037] In one embodiment, the distal end of the dilator is configured to engage the wall of the distal prostatic urethra without obstructing the seminal caruncle.

[0038] In one embodiment, the longitudinal struts on the distal end of the dilator are configured to engage the wall of the distal prostatic urethra without obstructing the verumontanum.

[0039] In one embodiment, the proximal end of the dilator is configured to engage the proximal prostatic urethra wall adjacent the prostatic transition zone.

[0040] In one embodiment, the longitudinal struts on the proximal end of the dilator are configured to engage the proximal prostatic urethra wall adjacent the prostatic transition zone.

[0041] In one embodiment, the longitudinal struts are configured to allow the dilator to bend differentially during use (different bends at the distal and proximal ends of the dilator), thereby allowing the dilator to conform to the shape of the body lumen wall and move with it.

[0042] In one embodiment, the longitudinal struts are formed by corrugated structural elements, such as sinusoidal elements. In one embodiment, the structural elements are wires or ribbons, such as metal wires or ribbons.

[0043] In one embodiment, the dilator comprises an elongated ring. In one embodiment, the elongated ring is formed from a corrugated structural element, typically a single corrugated structural element. In one embodiment, the elongated ring is formed from an expandable mesh.

[0044] On the other hand, the present invention provides a delivery device for the dilator of the present invention, the delivery device comprising a handle operably connected to a delivery tube and an expulsion element, the delivery tube having a hollow distal end away from the handle, which is configured to receive the dilator of the present invention in a contracted state, the expulsion element operably connected to the handle, and can be operated to discharge the dilator from the open end of the delivery tube. In one embodiment, the delivery tube is configured to be inserted into the urethra through the penis and used to deliver the dilator of the present invention to the prostatic urethra. In another embodiment, the delivery tube is configured to be inserted into the esophagus through the mouth and used to deliver the dilator of the present invention to the esophagus. In another embodiment, the delivery tube is configured to be inserted into the colon through the anus and used to deliver the dilator of the present invention to the colon. In one embodiment, the expulsion element includes a head configured to engage the proximal end of the dilator. This allows the expulsion element to grasp the dilator and move the dilator proximally (towards the handle-retract) and distally (away from the handle-expulsion). In one embodiment, the head of the expulsion element includes a clamp configured to engage the apex of at least one proximal fork. In one embodiment, the head of the discharge element includes a fixture configured to engage the vertices of all proximal forks, such as two, three, five or seven proximal forks. In one embodiment, the head of the discharge element is configured to extend into the lumen of the proximal end of the dilator. In one embodiment, the cross-sectional area of ​​the head of the discharge element matches the cross-sectional area of ​​the body cavity into which the dilator is to be inserted. In this way, when the dilator is radially contracted and inserted into the open end of the delivery tube, the head of the discharge element is inserted into the lumen of the proximal end of the dilator, forcing the dilator to present the cross-sectional shape of the head. In the case of the prostatic urethra, the head of the discharge element generally has a substantially triangular cross-section, and this forces the dilator to present a roughly triangular cross-sectional shape, which substantially matches the cross-sectional shape of the prostatic urethra. In one embodiment, the head of the discharge element has a roughly pentagonal cross-section. In one embodiment, the head of the discharge element has a roughly upper heptagonal cross-section.

[0045] In one embodiment, the delivery device includes an imaging device disposed within the hollow distal end of the delivery tube and configured to image the placement of the dilator. In one embodiment, the imaging device is disposed within the lumen of the delivery tube. In one embodiment, the imaging device is concentrically disposed within the lumen of the delivery tube. In one embodiment, the imaging device includes a light source configured to illuminate a portion of the body cavity adjacent to the end of the delivery device in use. In one embodiment, the imaging device is a cystoscope.

[0046] In another aspect, the present invention is designed to provide a method for treating a disease or condition characterized by contraction of a body cavity of a mammal, the method utilizing an implantable dilator (typically utilizing the implantable dilator of the present invention), the method comprising implanting the dilator into a contracted segment of the body cavity, whereby the dilator in an expanded orientation achieves in situ expansion of the contracted segment of the body cavity.

[0047] In one embodiment, the method comprises the following steps:

[0048] delivering the dilator in a radially contracted orientation through the body lumen to a target location within the body lumen, the target location being characterized as a contracted section of the body lumen; and

[0049] The dilator is allowed to expand the inner wall of the body cavity in the target area to a radially expanded state, so that the dilator in the expanded orientation achieves in situ expansion of the contracted section of the body cavity.

[0050] In one embodiment, the disease or disorder characterized by constriction of a mammalian body cavity is a urethral invasive disease.

[0051] In one embodiment, the urethral invasive disease is benign prostatic hyperplasia.

[0052] In one embodiment, the dilator is configured for elastic deformation and self-expansion from a radially contracted orientation suitable for transluminal delivery through the urinary tract to a radially expanded orientation capable of achieving in situ dilation of the prostatic urethra.

[0053] In one embodiment, the method of the present invention employs a delivery device configured to maintain a dilator in a radially contracted orientation, deliver the dilator in the radially contracted orientation through a body cavity and to a contracted section of the body cavity, and release the dilator at the contracted section of the body cavity.

[0054] In one embodiment, the delivery device includes a handle including an actuator configured to remotely release the dilator, wherein the method includes the step of triggering the actuator of the delivery device to remotely release the dilator at a target location within the prostatic urethra.

[0055] In one embodiment, the method of the present invention additionally employs an imaging device adapted to provide an image of a constricted section of a body lumen, the method comprising using the imaging device to properly position the dilator in the constricted section of the body lumen.

[0056] In one embodiment, the positioning step includes longitudinally adjusting the position of the dilator within the body cavity.

[0057] In one embodiment, the positioning step includes radially adjusting the position of the dilator within the body cavity.

[0058] In one embodiment, the delivery device includes a light at its distal end, wherein the step of delivering the dilator to the target location includes the step of guiding the delivery device and the dilator to the target area in the body cavity by externally monitoring the position of the light.

[0059] In one embodiment, the dilator is a dilator according to the present invention.

[0060] On the other hand, the present invention relates to a method for treating benign prostatic hyperplasia in mammals, the method using an implantable biocompatible dilator, the dilator being constructed for elastic deformation and self-expansion from a radially contracted orientation to a radially expanded orientation, the radially contracted orientation being suitable for transluminal delivery through the urinary tract, the radially expanded orientation being capable of achieving in situ expansion of the prostatic urethra, wherein the dilator is constructed to be installed in the prostatic urethra between the bladder neck and the external sphincter, the method comprising implanting the dilator in the prostatic urethra at a target area between the bladder neck and the external sphincter, the dilator in the radially expanded orientation thereby achieving in situ expansion of the prostatic urethra between the bladder neck and the external sphincter.

[0061] In one embodiment, the method comprises the following steps:

[0062] delivering the dilator in a radially contracted orientation through the urethra to a target location within the prostatic urethra between the bladder neck and the external sphincter; and

[0063] The dilator is allowed to expand to a radially expanded orientation against the prostatic urethra wall at the target location.

[0064] In one embodiment, the dilator is configured to achieve in situ dilation of the prostatic urethra at the target location without obstructing the verumontanum.

[0065] In one embodiment, the dilator is configured to fit in the prostatic urethra between the bladder neck and the external sphincter without inhibiting the function of the bladder neck.

[0066] In one embodiment, the dilator is configured to fit in the prostatic urethra between the bladder neck and the external sphincter without inhibiting the function of the bladder neck and the external sphincter.

[0067] In one embodiment, the dilator is configured to anatomically conform to the prostatic urethra wall.

[0068] In one embodiment, the dilator is elastically deformable to conform to the prostatic urethra wall as the shape and contour of the prostatic urethra wall changes, such as due to urination or ejaculation.

[0069] In one embodiment, the method of the present invention employs a delivery device configured to maintain a dilator in a radially contracted orientation, deliver the dilator in the radially contracted orientation through the urethra to the prostatic urethra, and release the dilator in the prostatic urethra, whereby the dilator self-expands to a radially expanded orientation upon release.

[0070] In one embodiment, the delivery device comprises a handle comprising an actuator configured to remotely release the dilator, wherein the method comprises the step of triggering the actuator of the delivery device to remotely release the dilator within the prostatic urethra.

[0071] In one embodiment, the dilator is configured to span a majority of the prostatic urethra between the bladder neck and the external sphincter.

[0072] In one embodiment of the method of the present invention, the dilator is configured to anatomically conform to the lumen of the prostatic urethra.

[0073] In one embodiment, the dilator is configured to dilate the prostatic urethra without obstructing the spermatic caruncle. For example, the dilator can include a structure of struts that provide an opening that is sized to overlap the spermatic caruncle.

[0074] In one embodiment, the dilator has a longitudinal dimension of 15 mm to 35 mm.

[0075] In one embodiment, the delivery device includes a light at its distal end, wherein the step of delivering the dilator to the prostatic urethra includes guiding the delivery device by externally monitoring the position of the light so that the dilator is located between the bladder neck and the external sphincter.

[0076] In one embodiment, the implantable dilator is an implantable dilator of the present invention.

[0077] In one embodiment, an implantable dilator for use in a method of the present invention comprises a hollow lumen and is configured for elastic deformation and self-expansion from a radially contracted orientation to a radially expanded orientation, the radially contracted orientation being suitable for transluminal delivery through the urinary tract, wherein the dilator is configured to fit within the prostatic urethra between the bladder neck and the external sphincter and span a substantial portion of the prostatic urethra without obstructing the verumontanum, the method comprising the steps of:

[0078] delivering the dilator in a radially contracted orientation through the urethra to a target location within the prostatic urethra between the bladder neck and the external sphincter; and

[0079] The dilator is allowed to expand against the prostatic urethra wall at the target location to a radially expanded orientation, whereby the dilator in the expanded orientation achieves in situ dilation of the prostatic urethra at the target location without obstructing the verumontanum and maintaining the function of the bladder neck.

[0080] Definition and general preferences

[0081] As used herein and unless expressly indicated otherwise, the following terms shall be deemed to have the following meanings, in addition to any broader (or narrower) meanings they may have in the art:

[0082] Unless the context requires otherwise, the singular herein shall be interpreted as including the plural, and vice versa. The term "a" or "an" used with respect to an entity shall be interpreted as referring to one or more of the entity. Thus, the terms "a", "one or more", and "at least one" are used interchangeably herein.

[0083] As used herein, the term "comprise" or variations such as "comprises / comprising" should be interpreted as referring to the inclusion of any listed integers (e.g., features, elements, characteristics, properties, method / process steps, or limitations) or groups of integers (e.g., several features, several elements, several characteristics, several properties, several method / process steps, or several limitations) but not the exclusion of any other integers or groups of integers. Therefore, as used herein, the term "comprises" is inclusive or open-ended and does not exclude additional unlisted integers or method / process steps.

[0084] As used herein, the term "disease" is used to define any abnormal state that impairs physiological function and is associated with specific symptoms. The term is used to broadly cover any disorder, condition, abnormality, pathology, disease, condition or syndrome in which physiological function is impaired, regardless of the nature of the cause (or whether the etiological basis of the disease is clear). It therefore includes conditions caused by infection, trauma, injury, surgery, radiation resection, poisoning or nutritional deficiencies.

[0085] As used herein, the term "treatment" or "treating" refers to an intervention (e.g., administration of a medicament to a subject) that cures, alleviates, or relieves the symptoms of a disease or eradicates its cause (or mitigates its effects) (e.g., reduces the accumulation of pathological levels of lysosomal enzymes). In this case, the term is used as a synonym for the term "therapy."

[0086] In addition, the term "treatment" refers to an intervention (e.g., administering a pharmaceutical agent to a subject) that prevents or delays the onset or progression of a disease, or reduces (or eradicates) its incidence in a treated population. In this case, the term "treatment" is used as a synonym for the term "prevention".

[0087] As used herein, an effective dose or therapeutically effective dose of a medicament is defined as a dose that can be administered to a subject without producing excessive toxicity, irritation, allergic reaction or other problems or complications, commensurate with a reasonable benefit / risk ratio; but sufficient to produce the desired effect, for example, a treatment or prevention that is manifested as a temporary or permanent improvement in the condition of the subject administered. The dose will vary depending on the subject administered and depends on factors such as the age, general condition, and route of administration of the individual subject. Therefore, while it is not possible to specify an exact effective dose, a person skilled in the art will be able to determine the appropriate "effective" dose for any individual case based on routine experiments and background common sense. The therapeutic outcome in this case includes eradication or alleviation of symptoms, relief of pain or discomfort, prolonged survival, improved mobility, and other signs of clinical improvement. The therapeutic outcome is not necessarily a cure.

[0088] Under the treatment and effective dose defined above, the term subject (which should be interpreted as including "individual", "animal", "patient" or "mammal" where the context permits) is defined as any subject, particularly a mammalian subject who is in need of treatment. Mammalian subjects include, but are not limited to, humans, domestic animals, farm animals, zoo animals, sports animals, pet animals, such as dogs, cats, guinea pigs, rabbits, rats, mice, horses, bulls, cows; primates, such as apes, monkeys, gorillas and chimpanzees; canines, such as dogs and wolves; felines, such as cats, lions and tigers; equines, such as horses, donkeys and zebras; food animals, such as cattle, pigs and sheep; ungulates, such as deer and giraffes; and rodents, such as mice, rats, hamsters and guinea pigs. In a preferred embodiment, the subject is a human.

[0089] "Implantable" for dilators suitable for use in the present invention refers to devices made of biocompatible materials, i.e., devices that generally do not elicit an immune response in the host and / or cause trauma, inflammation, or scarring. Examples of such materials include gold, titanium, cobalt-chromium alloys, tantalum alloys, nickel-titanium alloys, and several polymers.

[0090] "Dilator" refers to a biocompatible device with an inner cavity to allow liquid to flow through the dilator, and elastic deformation and self-expansion can occur between a relaxed expansion orientation and a contraction orientation, and the contraction orientation is suitable for transluminal delivery and sometimes percutaneous delivery, whereby the dilator applies an outward radial force to the wall of the body cavity in situ. The dilator is generally in the form of a roughly cylindrical shape and can be configured to fit the shape of a section of the body cavity. Dilators for arteries, veins, and urethra have been found in the literature, such as WO2015138763, CN202822454, and US5269802. The dilator can be made of any suitable material, such as stainless steel, shape memory polymers (such as linear block copolymers or other thermoplastic polymers with shape memory effect) and shape memory alloys (i.e., nickel-titanium alloys).

[0091] "Body cavity" refers to the elongated, tubular organs in the body, including the urinary tract, gastrointestinal tract, esophagus, and vasculature. "Urinary tract" refers to the urethra or ureter.

[0092] "Wave ring" means an annular device formed by a structural element that is, for example, wavy and has at least two distal prongs and at least two proximal prongs (see Figures 1 to 24 ) of a metal wire. The wave-shaped structural element can take the form of a substantially sinusoidal waveform (sinusoidal ring), a substantially square waveform (square wave-shaped ring), a waveform between a sinusoidal waveform and a square waveform, and any combination of these waveforms. In one embodiment, the wave-shaped ring has a substantially periodic waveform. In one embodiment, the wave-shaped ring has a non-periodic waveform. In one embodiment, the fork is substantially V-shaped. In one embodiment, the fork is substantially rectangular. In a preferred embodiment, the wave-shaped ring is a sinusoidal ring. In a preferred embodiment, the wave-shaped ring has three distal forks and three proximal forks. The wave-shaped ring with three distal forks and proximal forks is particularly suitable for treating benign prostatic hyperplasia. In one embodiment, at least one fork forms two or more sub-forks, for example, the fork can be W-shaped to form two sub-forks. In one embodiment, the width of the wave-shaped ring (in a relaxed state) is greater than the width of the diseased prostatic urethra. In one embodiment, the width of the wave-shaped ring (in a relaxed state) is 5-40% greater than the width of the diseased prostatic urethra. In one embodiment, the width of the wave-shaped ring (in a relaxed state) is 10-30% greater than the width of the diseased prostatic urethra.

[0093] "Elongated wave ring" refers to a wave ring whose longitudinal dimension is equal to or greater than its maximum transverse dimension when in a relaxed, expanded state. Typically, when in a relaxed, expanded state, the maximum longitudinal dimension is greater than its maximum transverse dimension. In general, the length of the wave ring is 10-45 mm. Typically, the width of the wave ring (in a relaxed state) is 6-30 mm. In one embodiment, the length of the wave ring is 15-25 mm. In one embodiment, the width of the wave ring (in a relaxed state) is 10-20 mm. In one embodiment, the length of the wave ring is at least 10% greater than its width (in a relaxed state). In one embodiment, the length of the wave ring is at least 20% greater than the width of the wave ring (in a relaxed state). In one embodiment, the length of the wave ring is at least 30% greater than its width (in a relaxed state). In one embodiment, the length of the wave ring is at least 40% greater than its width (in a relaxed state). In one embodiment, the length of the wave ring is 1-40% greater than its width (in a relaxed state). In one embodiment, the length of the wave ring is 5-40% greater than its width (in a relaxed state). In one embodiment, the length of the wave ring is 5-30% greater than its width (in a relaxed state). In one embodiment, the length of the wave loop is 5-20% greater than its width (in the relaxed state).

[0094] The "proximal prong" refers to the prong that is located on the delivery side of the body cavity when the dilator is in place in the body cavity. The "distal prong" refers to the prong that is located opposite the delivery side of the body cavity when the dilator is in place in the body cavity. For a dilator of the present invention configured for the treatment of benign prostatic hyperplasia, the proximal prong will generally be located near the external sphincter, and the distal prong will generally be located near the bladder neck.

[0095] "Elastic deformation and self-expansion" means that the expander can be radially compressed into a contracted orientation (suitable for transluminal delivery), and will present a relaxed expanded orientation when the compressive force is released. In this way, the expander is delivered in a contracted orientation using a suitable delivery tool, and the compressive force is released in situ at the target site, allowing the expander to apply an outward radial force against the body cavity wall. In general, the width of the expander in a relaxed state is greater than the width of the target body cavity. A variety of delivery devices are applicable, such as a delivery tube with a hollow end, which is sized to receive and hold the expander in a contracted orientation, whereby the expander expands when discharged from the delivery tube. Other delivery devices include a catheter with an outer sheath that surrounds the expander during delivery and allows the expander to expand when it is withdrawn after being in place. In one embodiment, the expander can be contracted to less than 50% of its cross-sectional area in a relaxed state. In one embodiment, the expander can be contracted to less than 40% of its cross-sectional area in a relaxed state. In one embodiment, the expander can be contracted to less than 30% of its cross-sectional area in a relaxed state. In this context, "cross-sectional area" refers to the cross-sectional area through the midpoint of the dilator and defined by the longitudinal struts.

[0096] By "radially collapsed orientation suitable for transluminal delivery" is meant that the dilator is radially collapsed to bring the prongs closer together, thereby significantly reducing the transverse profile of the ring so that it can be delivered through a body lumen.

[0097] "Relaxed radially expanded orientation" refers to the profile of the dilator when in a relaxed state.

[0098] "Substantial segment of the prostatic urethra" refers to at least 30% of the length of the prostatic urethra between the bladder neck and the external sphincter. In one embodiment, the wave ring is configured to span at least 40% of the length of the prostatic urethra between the bladder neck and the external sphincter. In one embodiment, the wave ring is configured to span at least 50% of the length of the prostatic urethra between the bladder neck and the external sphincter. In one embodiment, the wave ring is configured to span at least 60% of the length of the prostatic urethra between the bladder neck and the external sphincter. In one embodiment, the wave ring is configured to span at least 70% of the length of the prostatic urethra between the bladder neck and the external sphincter.

[0099] "Self-expanding" as applied to an elastically deformable dilator means that the dilator is adjustable between radially expanded and radially contracted configurations and is biased toward the radially expanded configuration.

[0100] "Diseases or conditions characterized by shrinkage of a mammalian body cavity" refers to, for example, proliferative conditions associated with a body cavity and causing shrinkage or deformity of the body cavity, as well as partial or complete obstruction, such as benign prostatic hyperplasia, or other proliferative or non-proliferative conditions, such as inflammation. In one embodiment, the body cavity is a body cavity of the renal system, such as the urethra or ureter. In one embodiment, the mammal is a human being, such as a male or female. In one embodiment, the condition is inflammation of the body cavity. In one embodiment, the condition is inflammation of the ureter or urethra (e.g., caused by trauma or kidney stones). In one embodiment, the condition is incontinence, such as stress urinary incontinence. In this embodiment, the dilator is typically placed in the urethra between the bladder neck and the external sphincter (usually for the purpose of reshaping the prostatic urethra).

[0101] The "target location" in the method for treating benign prostatic hyperplasia refers to a segment of the prostatic urethra between the bladder neck and the external sphincter, which spans a substantial segment of the prostatic urethra including the constricted segment. Typically, the target location is at least 5 mm from the external sphincter and the bladder neck. Typically, the target location is at least 10 mm from the external sphincter and the bladder neck.

[0102] When applied to dilators, "does not inhibit bladder neck function" means that the dilator does not affect bladder neck function when properly placed in the prostatic urethra between the bladder neck and the external sphincter and allows the bladder neck to open and close normally during urination and to contract forcefully during ejaculation.

[0103] When applied to dilators, "does not inhibit the function of the external sphincter" means that the dilator does not affect the function of the external sphincter when properly placed in the prostatic urethra between the bladder neck and the external sphincter, thereby allowing the sphincter to contract / spasm rhythmically during ejaculation. This is the muscle that propels the ejaculate during ejaculation in a normal antegrade manner (spasm of the external sphincter with tight closure of the bladder neck means that semen is pushed toward the penis).

[0104] The "Verumontanum" (or seminal colliculus) is a distinctive median ridge on the posterior wall of the prostatic urethra. It is an important landmark because it contains the slit-like openings of the ejaculatory ducts (containing semen) and the openings of the prostatic ducts (containing prostatic fluid).

[0105] When applied to a dilator, "non-blocking the seminal colunm" means that the dilator is constructed so that when the dilator is deployed to an expanded orientation in the prostatic urethra between the bladder neck and the external sphincter, it does not block the seminal colunm and reduces or completely avoids rupture, compression or damage to the seminal colunm which could lead to dysfunction of semen discharge into the prostatic urethra.

[0106] "Imaging devices" are devices that can image the urethra remotely from outside the body, such as ultrasound and CT scanners.

[0107] As applied to the dilator, "anatomically conforming" means that the dilator is configured to conform to the prostatic urethra wall. In one embodiment, this means that the dilator deforms to conform to the prostatic urethra wall when the shape and contour of the wall changes, such as during urination or ejaculation. BRIEF DESCRIPTION OF THE DRAWINGS

[0108] The invention will be more clearly understood from the description of embodiments given by way of example with reference to the accompanying drawings, in which:

[0109] Figure 1 is a front view of the trident dilator of the present invention in a relaxed and expanded state;

[0110] Figure 2 is in a state of contraction Figure 1 A front view of a trident dilator;

[0111] Figure 3 It is placed in the prostatic urethra of patients with benign prostatic hyperplasia Figure 1 A partial cross-sectional view of a dilator of , wherein the dilator exerts outward radial pressure on the prostatic urethra wall, causing dilation;

[0112] Figure 4 is similar to Figure 2 A partial cross-section of the urethra showing the seminal vesicles and ejaculatory ducts entering the prostatic urethra;

[0113] Figure 5 is a photograph of the dilator of the present invention after it is in place in the prostatic urethra, showing three proximal prongs and three distal prongs;

[0114] Figure 6 is a front view of a five-pronged dilator according to the present invention;

[0115] Figure 7 is a front view of a three-pronged dilator including a tapered sinusoidal ring according to the present invention;

[0116] Figure 8 is a front view of a three-pronged dilator including a cylindrical sinusoidal ring according to the present invention;

[0117] Fig. 9 is a front view of a three-pronged dilator according to the present invention, wherein the apexes of the prongs are flared outward;

[0118] Fig.10 is a front view of a three-pronged dilator according to the present invention, wherein the apex of the distal prong is flared outward;

[0119] Fig.11is a front view of a three-pronged dilator according to the present invention, wherein the apex of the distal prong includes an inwardly flared ring and the apex of the proximal prong includes an outwardly flared ring;

[0120] Fig.12 is a front view of a three-pronged dilator according to the present invention, which is similar to Fig.12 The dilator of claim 1, wherein the distal prongs are staggered in height and the proximal prongs are staggered in height to allow the distal prongs and the proximal prongs to overlap when the dilator is in a collapsed state;

[0121] Fig.13 yes Fig.12 A front view of the trident dilator is shown in a collapsed state.

[0122] Fig.14 is a front view of a three-pronged dilator of the present invention, wherein the tips of the distal and proximal forks are annular;

[0123] Fig.15 is a front view of a three-pronged dilator of the present invention, wherein the struts of the distal prongs are thicker than the struts of the proximal prongs;

[0124] Fig.16 is a front view of a three-pronged dilator of the present invention, wherein the tips of the distal forks are M-shaped structures, and wherein the end of the metal wire extends beyond one of the tips to act as a fixing barb;

[0125] Fig.17 is a front view of a three-pronged dilator of the present invention, wherein one end of the wire extends beyond one of the vertices to provide a coil having a barbed end;

[0126] Fig.18 is a front view of a three-pronged dilator of the present invention, wherein each end of the wire extends longitudinally beyond both ends of the dilator to serve as distal and proximal barbs;

[0127] Fig.19 yes Figure 1 A front view of a three-pronged dilator having an anchoring element disposed on one of the longitudinal struts;

[0128] Fig. 20 is a front view of a three-pronged dilator of the present invention, wherein each end of the wire extends longitudinally beyond both ends of the dilator to act as distal and proximal barbs extending circumferentially partially around both ends of the dilator;

[0129] Fig.21 is a front view of a three-pronged dilator of the present invention, having four substantially linear struts and four non-linear struts; Fig. 22It is a front view of the double-pronged dilator of the present invention in a relaxed and expanded state.

[0130] Fig.23 yes Fig. 22 A front view of a double-pronged dilator, wherein two longitudinal prongs contain anchoring elements;

[0131] Fig.24 is a front view of an alternative embodiment of a two-pronged dilator of the present invention in a relaxed and expanded state;

[0132] Fig.25 is a front view of an anchoring element disposed on a strut of the expander of the present invention;

[0133] Fig.26 is a front view of another embodiment of an anchoring element disposed on a strut of the expander of the present invention;

[0134] Fig. 27 is a front view of another embodiment of an anchoring element disposed on a strut of the expander of the present invention;

[0135] Fig.28 is a front view of another embodiment of an anchoring element disposed on a strut of the expander of the present invention;

[0136] Fig.29 is a front view of a delivery device for a dilator of the present invention prior to insertion of the dilator;

[0137] Fig.30 yes Fig. 20 A front view of a delivery device showing an in-situ expander in a collapsed orientation within a distal end of the delivery device;

[0138] Fig.31 yes Fig. 20 A front view of a delivery device of , showing the dilator in situ within the prostatic urethra after being expelled from the distal end of the device; and

[0139] Fig.32 is a front view of the distal end of the discharge element, which constitutes Fig.29 A portion of a conveying device;

[0140] FIG. 33 (A to D) illustrates a delivery device of the present invention comprising a cystoscope coaxially disposed with the lumen of the delivery device, the cystoscope being used to deliver the dilator of the present invention into the prostatic urethra;

[0141] Fig.34 A three-dimensional X-ray image of a dilator in situ in the prostatic urethra of a dog;

[0142] Fig.35 and 36This is a photo of the dilator of the present invention placed in the prostatic urethra of a dog. The ridge at the six o'clock position in the photo is the verumontanum;

[0143] Fig.37 A method for treating benign prostatic hyperplasia (BPH) is shown;

[0144] Fig.38 The dilator of the present invention is shown placed in the prostatic urethra between the bladder neck muscle and the external sphincter of a patient with benign prostatic hyperplasia. The figure shows how the device leaves room for the caruncle between the two vertices of the dilator in the distal prostatic urethra, and the proximal end of the device is configured so that one of the prongs pushes the transition zone of the prostate away from the prostatic urethral cavity. DETAILED DESCRIPTION

[0145] The present invention will now be described with reference to specific embodiments. These embodiments are merely exemplary and are intended for illustration only: they are not intended to limit the scope of the claimed exclusive right or the invention in any way. These examples constitute the best mode currently contemplated for carrying out the present invention.

[0146] Referring to the accompanying drawings and first to Figure 1 , shows a dilator according to the present invention, which is generally indicated by the reference numeral 1. The dilator 1 includes a single nickel-titanium alloy wire configured as an elongated sinusoidal loop, having a distal end 3 and a proximal end 6, the distal end 3 including three distal forks 4 with vertices 5, and the proximal end 6 including a proximal fork 7 with three vertices 8. These forks are connected by longitudinal struts 9. The dilator 1 is shown in an expanded relaxed state and has a length of approximately 22 mm and a width of approximately 15 mm. In the expanded state shown, the distance between the vertices 5 of adjacent distal forks 4 at the distal end 3 of the dilator is approximately 14 mm. Similarly, the distance between the vertices 8 of adjacent distal forks 7 at the proximal end 6 of the dilator is approximately 14 mm. The nickel-titanium alloy wire has a cross-sectional diameter of approximately 0.4 mm.

[0147] Reference Figure 2 , the dilator 1 is shown in a radially contracted state, in which the distal fork and the proximal fork are brought together. Figure 1 Compared to the relaxed expanded state shown, the cross-sectional area of ​​the dilator has been reduced by more than 70%, and the distance between adjacent distal and proximal prongs has been reduced from 14 mm to 4-5 mm. In this collapsed configuration, the elasticity of the sinusoidal ring construction causes the ring to exert an outward radial force.

[0148] Reference Figure 3 and Figure 4 , which demonstrated the use of Figure 1Dilator. The dilator 1 is disposed within the prostatic urethra 10 in the prostate between the bladder neck 12 and the external sphincter 13. In this position, the dilator 1 applies an outward radial force to the wall of the prostatic urethra 10, dilating the urethra to allow urine to flow. Due to the sinusoidal ring design, the outward radial force is greatest at each end of the dilator, adjacent to the transition zone of the prostatic urethra where the greatest amount of diseased tissue is located. In addition, due to the design of the dilator, the contact area between the struts and fork of the dilator and the wall of the prostatic urethra is minimized so that the vas 15 is not obstructed by the wall of the dilator. In addition, the dilator does not have any circumferential struts, facilitating removal.

[0149] Figure 5 is a photograph of a dilator of the present invention inserted into the prostatic urethra of a cadaver, showing the proximal end of the dilator in the foreground and the distal end of the dilator abutting the bladder neck in the background. The photograph shows how the struts of the dilator become embedded in the prostatic urethra wall.

[0150] refer to Figure 6 , shows a front view of a dilator according to an alternative embodiment of the present invention, wherein the components described with reference to the previous embodiment are assigned the same reference numerals. In this embodiment, the dilator 20 has five distal forks 4 and five proximal forks 7, and the use of this embodiment is the same as described with reference to the previous embodiment.

[0151] refer to Figure 7 , shows a front view of a dilator according to an alternative embodiment of the present invention, wherein the components described with reference to the previous embodiment are assigned the same reference numerals. In this embodiment, the dilator 30 has three distal prongs 4 and three proximal prongs 7 and tapers longitudinally inwardly toward the distal end 3, wherein the struts have an angle of 5° to 15° with the longitudinal axis of the dilator when in a relaxed state. The use of this embodiment is the same as described with reference to the previous embodiment.

[0152] refer to Figure 8 , shows a front view of a dilator according to an alternative embodiment of the present invention, wherein the components described with reference to the previous embodiment are given the same reference numerals. In this embodiment, the dilator 40 has three distal prongs 4 and three proximal prongs 7, and the struts are bent outwardly along their length so that the dilator is generally cylindrical along its length. The use of this embodiment is the same as described with reference to the previous embodiment.

[0153] refer to Fig. 9, shows a front view of a dilator according to an alternative embodiment of the present invention, wherein the components described with reference to the previous embodiment are given the same reference numerals. In this embodiment, the dilator 50 has three distal prongs 4 and three proximal prongs 7, and the struts are bent inwardly along their length so that the dilator has a generally waisted shape along its length, with a narrowed central portion 51 and slightly widened ends 3, 6. In addition, the apex 5, 8 at each end is flared outwardly. The use of this embodiment is the same as described with reference to the previous embodiment.

[0154] Reference Fig.10 , shows a front view of a dilator according to an alternative embodiment of the present invention, wherein the components described with reference to the previous embodiment are given the same reference numerals. In this embodiment, the dilator 60 has five distal forks 4 and five proximal forks 7, and the apex 5 at the distal end 3 is flared outward. The use of this embodiment is the same as described with reference to the previous embodiment.

[0155] refer to Fig.11 , shows a front view of a dilator according to an alternative embodiment of the present invention, wherein the components described with reference to the previous embodiment are given the same reference numerals. In this embodiment, the dilator 70 has three distal forks 4 and three proximal forks 7. The apex 5 at the distal end 3 is formed as a radially inwardly protruding ring 71, and the apex 8 at the proximal end 6 forms a radially outwardly protruding ring 72. The use of this embodiment is the same as described with reference to the previous embodiment.

[0156] Reference Fig.12 and Fig.13 , shows a front view of a dilator according to an alternative embodiment of the present invention, wherein the components described with reference to the previous embodiment are assigned the same reference numerals. In this embodiment, the dilator 80 has three distal forks 4 and three proximal forks 7. The apex 5 at the distal end 3 forms a ring 81 protruding radially inward, and the apex 8 at the proximal end 6 forms a ring 82 protruding radially outward. In addition, the longitudinal positions of the distal forks and the proximal forks are staggered so that when the dilator is in the contracted state ( Fig.13 The use of this embodiment is the same as described with reference to the previous embodiment.

[0157] refer to Fig.14, shows a front view of a dilator according to an alternative embodiment of the present invention, wherein the components described with reference to the previous embodiment are given the same reference numerals. In this embodiment, the dilator 90 has three distal forks 4 and three proximal forks 7. The apex 5 at the distal end 3 is formed as a ring 91 protruding along the longitudinal axis of the dilator, and the apex 8 at the proximal end 6 forms a ring 92 protruding along the longitudinal axis of the dilator. In addition, the struts are bent outwardly. The use of this embodiment is the same as described with reference to the previous embodiment.

[0158] refer to Fig.15 , shows a dilator according to an alternative embodiment of the present invention, wherein the components described with reference to the previous embodiment are assigned the same reference numerals. In this embodiment, the dilator 100 is formed from a nickel-titanium alloy wire of varying thickness along its length, wherein the portion of the alloy wire constituting the distal fork 4 is thicker than the portion constituting the proximal fork 7. The use of this embodiment is the same as described with reference to the previous embodiment.

[0159] refer to Fig.16 , shows a front view of a dilator according to an alternative embodiment of the present invention, wherein the components described with reference to the previous embodiment are given the same reference numerals. In this embodiment, the dilator 110 has three distal forks 4 and three proximal forks 7. The apex 5 at the distal end 3 includes an M-shaped ring 111 protruding along the longitudinal axis of the dilator. In addition, the nickel-titanium alloy wire has an end 112 that extends beyond the distal end 3 of the dilator and includes an end barb 113 (anchoring element) for fixing the dilator in place. The use of this embodiment is the same as described with reference to the previous embodiment.

[0160] refer to Fig.17 , shows a front view of a dilator according to an alternative embodiment of the present invention, wherein the components described with reference to the previous embodiment are given the same reference numerals. Fig.16 The embodiment of the present invention is different in that the end of the nickel titanium alloy wire forms two spiral loops 114 and terminates in an anchor 113 (anchoring element) for fixing the expander in place. The use of this embodiment is the same as described in the previous embodiment.

[0161] Reference Fig.18 , shows a front view of a dilator according to an alternative embodiment of the present invention, wherein the components described with reference to the previous embodiment are given the same reference numerals. In this embodiment, the dilator 120 has three distal prongs 4 and three proximal prongs 7 and is formed of nickel-titanium alloy wires overlapping at a junction 121 and has ends 122 and 123 that extend longitudinally beyond the ends of the dilator and include end barbs 124 for securing the dilator in place (anchoring elements). The use of this embodiment is the same as described with reference to the previous embodiment.

[0162] refer to Fig.19 , shows a front view of an expander according to an alternative embodiment of the present invention, wherein the components described with reference to the previous embodiment are given the same reference numerals. In this embodiment, the expander comprises an anchoring element 126 disposed on the longitudinal strut 9, the anchoring element comprising a strut surrounding sleeve 127 and an upwardly protruding barb 128.

[0163] refer to Fig. 20 , shows a front view of a dilator according to an alternative embodiment of the present invention, wherein the components described with reference to the previous embodiment are given the same reference numerals. Fig.18 The embodiment of the present invention differs in that the ends 122 and 123 extend substantially circumferentially around each end of the expander and include end barbs 124 for securing the expander in place. The use of this embodiment is the same as described with reference to the previous embodiment.

[0164] refer to Fig.21 , shows a front view of a dilator according to an alternative embodiment of the present invention, wherein the components described with reference to the previous embodiment are given the same reference numerals. In this embodiment, the dilator 130 has three distal forks 4 and three proximal forks 7, and tapers longitudinally inwardly toward the distal end 3, wherein the angle between the struts and the longitudinal axis of the dilator when in a relaxed state is between 5 degrees and 15 degrees. In addition, two adjacent struts 131 are bent inwardly between the two ends, thereby providing different angular spacings between the struts. The use of this embodiment is the same as described with reference to the previous embodiment.

[0165] refer to Fig. 22 , shows a front view of a dilator according to an alternative embodiment of the present invention, wherein the components described with reference to the previous embodiment are given the same reference numerals. In this embodiment, the dilator 150 is Figure 1 The dilator shown in FIG. 1 is substantially the same except that the dilator includes two distal prongs 4 and proximal prongs 7 instead of three. The operation of this embodiment is similar to that of FIG. Figure 1 The same as the embodiment.

[0166] refer to Fig.23 , the figure shows a device with an anchoring element 126 arranged on a longitudinal strut 9 Fig. 22 Each anchoring element 126 comprises a sleeve 127 surrounding the strut 9 and a pair of barbs 128 projecting away from the strut at right angles to each other.

[0167] refer to Fig.24, shows a front view of a dilator according to an alternative embodiment of the present invention, wherein the components described with reference to the previous embodiment are given the same reference numerals. In this embodiment, the dilator 150 is Fig. 22 The dilator shown in is substantially the same, with the difference that the apex of the distal prong 4 is rounded.

[0168] refer to Figure 25 to Figure 28 , shows multiple embodiments of anchoring elements 126, each anchoring element 126 includes a sleeve 127, the sleeve 127 is configured to surround the pillar 9 of the dilator of the present invention, and has a barb 128 protruding away from the pillar, and is embedded in the body cavity wall after being in place. Fig.25 In the embodiment of the present invention, the barbs 128 are mounted at each end of the top of the sleeve 127 and project upwardly away from the post at an angle of approximately 45° to the post. Fig.26 In the embodiment of the present invention, one of the barbs 128 protrudes from the top of one end of the sleeve 127, while the other barb 128 protrudes from the bottom of the other end of the expander. Fig. 27 In the embodiment of FIG. 1 , the barb 128 is cut from the top of the sleeve 127. Fig.28 In the embodiment of FIG. 1 , the wire 129 is installed inside the sleeve 127 , and each end of the wire 129 protrudes from the sleeve 127 to form a barb 128 .

[0169] Reference Figure 29 to Figure 31 , illustrates a delivery device for delivering the dilator of the present invention to a target site in a body cavity, specifically, to the prostatic urethra. The device 200 includes a handle 201, a delivery tube 202, and a discharge element 205, wherein the delivery tube 202 has a hollow distal end 203 away from the handle 201, and the hollow distal end 203 is configured to receive the dilator of the present invention in a contracted state, and the discharge element 205 is operably connected to the handle 201 and is operable to discharge the dilator from the open end of the delivery tube. In more detail, the discharge device 205 includes a shunt mechanism having a distal end 206 operably connected to an actuating device 207 on the handle and a proximal end disposed adjacent to the distal end 203 of the tube 202. In use, the shunt mechanism is retracted and the dilator 1 is manually compressed into a contracted shape and inserted into the hollow distal end ( Fig.30 ). The delivery tube is then inserted into the urethra through the penis and advanced along the urethra until the distal end of the delivery tube is located within the prostatic urethra 10. The actuating device 207 on the handle is then actuated to extend the push mechanism and discharge the dilator 1 from the delivery tube into the prostatic urethra, where it expands to apply radially outward pressure to the prostatic urethra wall ( Fig.31 ). The delivery tube is then retracted from the urethra.

[0170] Reference Fig.32 , provides Fig.29Detailed front view of a portion of a delivery device 200 of FIG. 20. In this embodiment, the expulsion element 205 includes a distal head 210 having a triangular cross-section and configured to fit into the cavity of the dilator when it is installed in the delivery tube 202. Each of the three faces of the head 210 includes a protrusion 211 that together form a fixture for positioning and engaging the dilator in the delivery tube, and each protrusion 211 is configured to engage the apex of the proximal prong of the dilator. Operation and Reference Figure 29 to Figure 31 The embodiment described above is the same as that described above, except that the clamp engages the dilator so that the expulsion element can push and pull the dilator along the delivery tube, which allows the surgeon to partially advance the dilator into the body cavity and then retract the dilator if they feel that the dilator is not in the correct position.

[0171] Reference FIG. 33A to FIG. 33D , showing that the delivery device of the present invention 300 is used to deliver the dilator 1 of the present invention into the prostatic urethra 10, which is surrounded by the prostate 11 and is disposed distally to the bladder 301. The delivery device 300 includes a cystoscope 302, which is coaxially disposed in the lumen of the delivery device 300 and has a distal end that is substantially flush with the distal end of the delivery tube 202. Fig.33A As shown, the dilator is mounted within a delivery tube 202, with a cystoscope 302 protruding through the lumen of the dilator. The cystoscope includes a light that illuminates the urethra at the distal end of the delivery device, thereby assisting the surgeon in remotely imaging the urethra prior to deploying the dilator. Fig.33B ), and imaging of the urethra and dilator during deployment ( Fig.33C ) and after unfolding, imaging ( Fig.33D ).

[0172] refer to Fig.37, a method of treating benign prostatic hyperplasia (BPH) is shown, wherein a dilator 300 is implanted in a prostatic urethra 310 between a bladder neck 312 and an external sphincter 313. The dilator is capable of self-expanding between a radially contracted configuration (not shown, but used during deployment) and a radially expanded configuration (shown), wherein the dilator enlarges the prostatic urethra to alleviate some of the patient's benign prostatic symptoms, in particular it widens the narrow urethra, provides less resistance to urine during urination and allows urine to pass through the diseased prostatic urethra (previously the urine stream would encounter a narrow high-pressure cavity). The dilator is configured to fit the prostatic urethra between the bladder neck 312 and the external sphincter 313 so that it does not interfere with the function of either. Since ejaculation requires the bladder neck to contract and the external sphincter to spasm, the dilator allows both functions when properly positioned between the bladder neck and the external sphincter, thereby addressing one of the shortcomings of known implants for treating BPH: impaired ejaculation ability and sexual dysfunction. In addition, because the function of the bladder neck is not affected when the dilator is in place, urine will not accumulate in the prostatic urethra for a long time, thereby preventing the dilator from crusting. In addition, the dilator is constructed so that when it is placed in place and correctly positioned in the prostatic urethra, obstruction of the spermatic colunm 315 (and the sexual dysfunction caused by it) is avoided. To this end, the proximal end of the dilator 300 includes a suitably shaped cutout 316 that prevents the side wall of the dilator 300 from contacting the spermatic colunm. In this embodiment, the dilator 300 is not limited to the wavy ring structure of the aforementioned embodiment, but may include any form of shape, such as a mesh body commonly used in dilators, or any other type of shape that can be adjusted between a radially contracted orientation suitable for delivery and a radially expanded state that can dilate the prostatic urethra while allowing urine to flow.

[0173] See also Fig.38 , shows the dilator of the present invention placed in the prostatic urethra of a patient with benign prostatic hyperplasia between the bladder neck muscle and the external sphincter. The figure shows how the device accommodates the verumontanum between the two prongs of the dilator in the distal prostatic urethra, while the proximal end of the device is configured so that one of the prongs pushes the transition zone of the prostate away from the prostatic urethral cavity.

[0174] Equivalent deformation:

[0175] The foregoing details are preferred embodiments of the present invention. In view of these descriptions, a person skilled in the art should be able to make various modifications and variations when implementing the present invention. These modifications and variations should be included in the claims attached to the present invention.

Claims

1. A delivery device for delivering an implantable biocompatible dilator to the prostatic urethra for treating benign prostatic hyperplasia (BPH), the dilator comprising a single elongated wavy ring having a proximal end and a distal end, the proximal end comprising proximal forks each having a corresponding proximal apex, the distal end comprising distal forks each having a corresponding distal apex, and a plurality of struts extending between the proximal apex and the distal apex, the plurality of struts curving outwardly along their length and tapering inwardly at each end so that the dilator has a cylindrical shape along its length, the delivery device comprising: a handle operably connected to a delivery tube, the delivery tube including a hollow distal end distal to the handle, wherein the dilator is received by the delivery tube in a radially collapsed configuration suitable for transluminal delivery through the urethra; as well as an expulsion element operably connected to the handle and operable to expel the dilator from the hollow distal end of the delivery tube, whereby the dilator can adopt a radially expanded configuration within the urethra; wherein the expulsion element comprises a head configured to extend into the lumen of the proximal end of the dilator, wherein the head comprises a clamp configured to engage at least one of the proximal apexes of the dilator; as well as An imaging device is disposed within the hollow distal end of the delivery tube, the imaging device protruding through the lumen of the dilator for imaging the urethra and the distal apex of the dilator during placement of the dilator in the urethra.

2. The delivery device of claim 1, wherein the expulsion element is configured to grasp the dilator and effect proximal movement of the dilator.

3. A delivery device according to claim 1 or 2, wherein the clamp is configured to engage the entire proximal apex of the dilator.

4. The delivery device according to claim 1 or 2, wherein the cross-sectional area of ​​the head of the discharge element matches the cross-sectional area of ​​the urethra.

5. The conveying device according to claim 1 or 2, wherein the head of the discharge element has a triangular cross section.

6. A delivery device according to claim 5, wherein the head of the discharge element includes a distal head having a triangular cross-section defined by three faces and configured to fit into the cavity of the dilator when it is installed in the delivery tube, wherein each of the three faces of the head includes a protrusion that together form a clamp for positioning and engaging the dilator in the delivery tube, and each protrusion is configured to engage the apex of the proximal fork of the dilator.

7. The delivery device according to claim 1 or 2, wherein the imaging device is concentrically disposed within the lumen of the delivery tube.

8. A delivery device according to claim 1 or 2, wherein the imaging device includes a light source configured to illuminate a portion of the urethra adjacent to the end of the delivery device in use.

9. The delivery device of claim 1 or 2, wherein the imaging device is a cystoscope.

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