Auxiliary implantation device for prostate stent

Abstract

The invention discloses an auxiliary implantation device for a prostate stent. The auxiliary implantation device comprises an outer tube, an expansion assembly and an inner tube, the outer pipe is provided with an axially through hollow cavity; the expansion assembly is connected with the outer tube and provided with a deformable expansion channel, an inlet of the expansion assembly is connected with an outlet of the hollow cavity, the cross section area of the expansion channel after expansion is larger than that of the hollow cavity, and the expansion channel is used for buffering impact of bouncing off of the prostate stent. The inner tube is arranged in the outer tube in a sleeved mode, can move axially and is used for pushing the prostate stent to the expansion channel. The invention aims to provide an auxiliary implantation device for a prostate stent. The auxiliary implantation device can prevent the prostate stent from possibly causing impact damage to surrounding tissues in the bounce-off process.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and in particular to an auxiliary device for prostate stent placement. Background Technology

[0002] With the widespread application of minimally invasive interventional techniques in urology, prostate stent placement has become an important method for treating lower urinary tract obstruction caused by benign prostatic hyperplasia. This technique maintains the patency of human tissue by implanting a metallic or biodegradable prostate stent, offering advantages such as minimal trauma and rapid recovery, and has shown good therapeutic effects in clinical applications. However, due to the unique anatomical structure of human tissue and the limitations of the operating space during prostate stent placement, prostate stent delivery technology still faces many challenges, which to some extent restricts its further promotion and application.

[0003] Existing prostate stent placement devices have significant technical shortcomings in clinical use. During stent deployment, traditional devices involve direct contact between the stent and surrounding tissue, easily leading to mucosal damage, postoperative hematuria, and exacerbated inflammation, among other clinical complications. This mechanical stimulation can cause mucosal damage and postoperative hematuria, and traditional deployment devices lack effective tissue protection mechanisms. These technical deficiencies not only affect surgical outcomes but may also increase the risks of postoperative infection and stent displacement, necessitating technological innovation to address these issues. Summary of the Invention

[0004] In order to overcome the shortcomings of the prior art, the purpose of this invention is to provide an auxiliary device for the placement of a prostate stent, which can prevent the prostate stent from causing impact damage to surrounding tissues during the pop-out process.

[0005] The objective of this invention is achieved through the following technical solution:

[0006] An assistive device for prostate stent placement, comprising:

[0007] An outer tube having a through hollow cavity;

[0008] An expansion assembly is connected to the outer tube and is used to expand the tissue in the target tissue area of ​​the human body. The expansion assembly is provided with an expansion channel. The inlet of the expansion channel is connected to the outlet of the hollow cavity. The expansion assembly can deform to enlarge or reduce the cross-sectional area of ​​the expansion channel. After the cross-sectional area of ​​the expansion channel is enlarged, it is larger than the cross-sectional area of ​​the hollow cavity. The inner wall of the expansion channel is used to block the prostate stent when it springs open.

[0009] The inner tube is fitted inside the hollow cavity of the outer tube and extends along the length of the outer tube. The inner tube can move relative to the hollow cavity axially. The inner tube is used to push the prostate stent to the dilation channel.

[0010] Furthermore, the expansion assembly also includes a first expansion member and a second expansion member, both of which are arc-shaped structures. The end of the first expansion member away from the target tissue area of ​​the human body and the end of the second expansion member away from the target tissue area of ​​the human body are hinged to each other through a hinge structure and together form the expansion channel.

[0011] Furthermore, at least one of the first and second expansion members has a guide boss structure on its inner wall. The guide boss structure is located on the path of the inner tube as it travels toward the target tissue area of ​​the human body, so that it can be supported by the inner tube and cause the first and second expansion members to move away from each other.

[0012] Furthermore, the guide boss structure is located at one end of the expansion channel away from the target tissue area of ​​the human body; the guide boss structure includes a guide ramp, which is located at one end of the guide boss structure away from the target tissue area of ​​the human body.

[0013] Furthermore, the outer wall of the inner tube near the target tissue area of ​​the human body is provided with a positioning protrusion. The end of the positioning protrusion near the target tissue area of ​​the human body is the prostate stent abutment end. The outer wall of the prostate stent abutment end is provided with an anti-slip structure. The anti-slip structure is used to abut the prostate stent and the guide protrusion structure.

[0014] Furthermore, the end of the positioning boss away from the prostate stent abutment end is the retraction linkage end of the expansion component, and the guide boss structure can slide down to the axial side of the retraction linkage end and abut against the retraction linkage end.

[0015] Furthermore, the hinge structure is connected with a torsion spring, one end of which elastically abuts against the first expansion member, and the other end of which elastically abuts against the second expansion member. The torsion spring has a tendency to drive the first expansion member and the second expansion member to move closer to each other.

[0016] Furthermore, one of the first expansion member and the second expansion member is provided with a magnet, and the other is provided with a magnetic element, wherein the magnet and the magnetic element are attracted to each other.

[0017] Furthermore, the expansion component also includes a limiting structure, which includes a protruding structure and a recessed structure that cooperate with each other; the protruding structure is located at the connecting end face of the first expansion member; and the recessed structure is located at the connecting end face of the second expansion member.

[0018] The distal ends of the first expansion member and the second expansion member are provided with a buffer structure, the buffer structure including a first tapering structure and a second tapering structure; the cross-sectional dimension of the first tapering structure gradually decreases along the distance from the target tissue area of ​​the human body; the cross-sectional dimension of the second tapering structure gradually decreases along the distance from the target tissue area of ​​the human body, and the first tapering structure and the second tapering structure are provided correspondingly.

[0019] Furthermore, at least one of the interiors of the first expansion member and the second expansion member is provided with a release guide structure; the release guide structure extends axially along the first expansion member or the second expansion member; the release guide structure is located at one end of the guide boss structure near the target tissue area of ​​the human body, and the release guide structure extends along one end near the target tissue area of ​​the human body towards the expansion channel, and the release guide structure is used to guide the prostate stent.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0021] 1. Design of the dilation channel: When the prostate stent placement device is in a contracted state, the dilation component remains contracted, forming a contracted dilation channel. The inner tube pushes the compressed prostate stent through the outer tube lumen. Upon reaching the target tissue area, the dilation component expands to create a release space. The inner tube then pushes the prostate stent into the dilation channel for release. The inner wall of the dilation channel effectively cushions the impact force of the prostate stent's release. After release, the dilation component retracts, and the entire device is smoothly withdrawn, ensuring a safe and reliable procedure. This process achieves precise positioning and gentle release of the prostate stent, while preventing potential impact damage to surrounding tissues during the stent's release.

[0022] 2. Design of the Protrusion Linkage Mechanism: The axial thrust of the inner tube is converted into radial expansion force through the guide protrusion structure, driving the first and second expansion components to unfold smoothly and form the required expansion channel. This mechanism integrates the elastic reset function of the torsion spring and the positioning and holding characteristics of the magnetic components and limiting structure, enabling the expansion components to reliably self-lock at any unfolded position, ensuring both the stability of the release process and the controllability of the operation. This linkage design achieves precise force transmission and conversion during the release of the prostate stent, effectively avoiding the impact damage problem common in traditional devices.

[0023] 3. Design of the retraction linkage mechanism: The retraction linkage end of the positioning boss and the guide boss structure form a linkage mechanism. When retracting the device of this invention, the guide boss structure slides along the receiving cavity of the outer wall of the positioning boss and contacts the retraction linkage end. Utilizing the receiving cavity formed by the axial height difference between the positioning boss and the inner tube, under the action of the natural retraction force of human tissue or the force of the torsion spring, the guide boss structure is pressed into the receiving cavity, forcing the first and second expansion members to rotate and retract around the hinge point, realizing a smooth transition of the expansion assembly from the expanded state to the contracted state. At this time, the retraction linkage end forms a mechanical stop, and the retraction force is evenly transmitted to the entire expansion assembly through the bearing surface formed by the retraction linkage end and the guide boss structure, driving the outer tube to retract synchronously. This mechanism realizes the three-linkage synchronous retraction of the inner tube, outer tube, and expansion assembly, ensuring that the device will not disturb the inserted support when withdrawing, and can evenly release tissue pressure, completing the safe withdrawal of the device. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of an auxiliary device for prostate stent placement according to the present invention;

[0025] Figure 2 for Figure 1 The diagram shows a cross-sectional view of an auxiliary device for prostate stent placement, wherein the dilation component is in an expanded state;

[0026] Figure 3 for Figure 2 The diagram shows a schematic of a prostate stent placement device in its retracted state, wherein the expansion component is in the retracted state.

[0027] In the diagram: 1. Outer tube; 2. Expansion assembly; 3. Expansion channel; 4. Inner tube; 5. First expansion component; 6. Second expansion component; 7. Hinge structure; 8. Guide boss structure; 9. Guide slope; 10. Positioning boss; 11. Prostate stent abutment end; 12. Anti-slip structure; 13. Retraction linkage end; 14. Torsion spring; 15. Magnet; 16. Magnetic element; 17. Protruding structure; 18. Recessed structure; 19. First tapering structure; 20. Second tapering structure; 21. Release guide structure; 22. Prostate stent. Detailed Implementation

[0028] The present invention will now be further described in conjunction with the accompanying drawings and specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0029] It should be noted that when an element is described as being "fixed to" another element, it can be directly attached to the other element or there may be an intervening element. When an element is described as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementations.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0031] See Figure 1 , Figure 2 A preferred embodiment of the present invention is described below:

[0032] An auxiliary device for prostate stent placement includes: an outer tube 1, an expansion component 2, and an inner tube 4; the outer tube 1 has an axially penetrating hollow cavity; the expansion component 2 is connected to the outer tube 1 and is used to expand the tissue of the target tissue area of ​​the human body, and the expansion component 2 is provided with an expansion channel 3; the inlet of the expansion channel is connected to the outlet of the hollow cavity; the expansion component 2 can deform to expand or shrink the cross-sectional area of ​​the expansion channel 3, and the expanded cross-sectional area of ​​the expansion channel 3 is larger than the cross-sectional area of ​​the hollow cavity, and the inner wall of the expansion channel 3 is used to separate the prostate stent 22 when it springs open; the inner tube 4 is sleeved in the hollow cavity of the outer tube 1 and extends along the length direction of the outer tube 1, and the inner tube 4 can move relative to the hollow cavity axially; the inner tube 4 is used to push the prostate stent 22 into the expansion channel 3.

[0033] The working principle of the prostate stent 22 assisted placement device is as follows: During the delivery stage, the expansion component 2 in a contracted state forms a continuous channel with the outer tube 1, and the inner tube 4 pushes the compressed prostate stent 22 through the cavity of the outer tube 1; when it reaches the target tissue area, the expansion component 2 dynamically expands through hinge linkage, material deformation or staged deployment, forming a release space larger than the cavity of the outer tube 1. At this time, the inner tube 4 continues to push forward to make the prostate stent 22 enter the expansion channel 3. The inner wall of the expansion channel 3 absorbs the impact force when the prostate stent 22 pops open through the buffer layer, while maintaining the protection of the surrounding tissues; after the release is completed, the expansion component 2 resets and narrows the channel, and the entire device can be safely withdrawn.

[0034] In practice: the operator first inserts the compressed prostate stent 22 into the front end of the inner tube 4 (i.e., the end closest to the target tissue area), and the entire device is pushed through the body's natural cavities; after confirming the target position through image positioning and endoscopy, the expansion component 2 is manually or automatically triggered to unfold, forming an expanded expansion channel 3; then the inner tube 4 is pushed to deliver the prostate stent 22 into the expansion area. After the constraint is released, the prostate stent 22 unfolds on its own elasticity, and the buffer layer of the expansion channel 3 evenly disperses the radial impact force; after release, the stent is stably placed by retracting the inner tube 4, releasing magnetic adsorption, or thermal separation, etc. Finally, the expansion component 2 is contracted and the entire prostate stent auxiliary placement device is withdrawn, completing the placement process.

[0035] Obviously, based on the through-hole hollow cavity of the outer tube 1, the inner tube 4 can move relative to it along the axial direction of the hollow cavity, allowing the inner tube 4 to be inserted into the hollow cavity, thereby pushing the prostate stent 22 and allowing it to be ejected from the hollow cavity. Since the expansion component 2 is connected to the outer tube 1 and can expand the tissue in the target tissue area, it provides release space for the prostate stent 22. The expansion component 2 has an expansion channel 3 whose inlet connects to the outlet of the hollow cavity of the outer tube 1, allowing the prostate stent 22 to enter the expansion channel 3 after leaving the hollow cavity, preventing it from directly falling into the target tissue area. Specifically, the expansion component 2 can deform to increase the cross-sectional area of ​​the expansion channel 3, making it larger than the cross-sectional area of ​​the hollow cavity, thus providing release space for the prostate stent 22 placed within the expansion channel 3. The expansion component 2 can also deform to decrease the cross-sectional area of ​​the expansion channel 3, facilitating the removal of the outer tube 1 from the body. Importantly, the prostate stent 22 expands on its own elasticity after the restraint is released, and the inner wall of the expansion channel 3 can replace human tissue to buffer the radial impact force when the prostate stent 22 is released.

[0036] Furthermore, the outer tube 1 can be made of medical-grade polymer material, combining flexibility and rigidity to ensure that the hollow cavity can accommodate the inner tube 4 and allow the prostate stent 22 to move freely. The cavity diameter should be controlled to be 1 to 1.5 times the size of the prostate stent 22 before release, which can accommodate the prostate stent 22 while avoiding an excessively large outer tube 1 (affecting its suitability for human implantation). In addition, the outer tube 1 can be designed with a segmented structure, with the end away from the target tissue area using a rigid material to ensure delivery stability, and the end closer to the target tissue area using a soft material (such as silicone) to reduce tissue damage. If a soft material such as a rope is used instead of the outer tube 1, its tensile strength must be sufficient to drive the expansion component 2, and its surface must be coated with a lubricating coating to reduce frictional resistance.

[0037] The core of the expansion component 2 is to release the stent in advance through the dynamic expansion channel 3, thus buffering the impact force when the prostate stent 22 pops open. Its structure can be designed as a hinged angle expansion structure (or a flexible expansion structure or a staged expansion structure). During the delivery phase, the expansion channel 3 maintains a small cross-sectional area to adapt to the body cavity. After reaching the target area, it dynamically expands to accommodate the space of the released prostate stent 22. This adjustable expansion characteristic ensures both delivery smoothness and buffers the release impact. The hinged angle structure achieves precise expansion through mechanical linkage, the flexible structure expands autonomously by relying on material deformation (such as shape memory alloy or thermally responsive hydrogel), and the staged structure gradually absorbs impact energy through progressive unfolding. All three require a buffer layer on the inner wall of the channel to further disperse local pressure.

[0038] The core function of the inner tube 4 is to achieve safe delivery and precise release of the prostate stent 22 through stable connection. The connection method can be direct contact (the contact surface must be larger than the cross-sectional area of ​​the prostate stent 22 to prevent accidental detachment during transportation), thermal response detachment (using body temperature responsive materials such as polycaprolactone to achieve automatic separation), mechanical snap-fit ​​structure (achieving controllable release through mechanical linkage such as slide rails or threads), or magnetic adsorption (using magnet 15 for remote separation). This ensures that the device can reliably release the prostate stent 22 without causing displacement after reaching the target tissue area. Among them, the direct contact method requires the contact surface to be provided with anti-slip texture or micro-convex structure to enhance transportation stability. At the same time, axial micro-movement or lubricating coating promotes the final smooth separation. All designs must meet biocompatibility requirements and take into account ease of operation.

[0039] Preferably, the expansion component 2 further includes a first expansion member 5 and a second expansion member 6. Both the first expansion member 5 and the second expansion member 6 are arc-shaped structures. The end of the first expansion member 5 that is away from the target tissue area of ​​the human body and the end of the second expansion member 6 that is away from the target tissue area of ​​the human body are hinged to each other through a hinge structure 7 and together form an expansion channel 3. The expansion assembly 2 also includes a first expansion member 5 and a second expansion member 6 that cooperate with each other. Both are arc-shaped structures, preferably circular tubes. Their proximal ends, which are far from the target tissue area of ​​the human body, are hinged to each other by a hinge structure 7, together forming a dynamically adjustable expansion channel 3. The hinge structure 7 allows the first and second expansion members 6 to remain in a closed state during the delivery phase to form a channel with the smallest cross-sectional area. During the release phase, they are expanded into a trumpet shape by external force traction or shape memory effect, causing the distal ends of the two expansion members to swing outward, thereby expanding the cross-sectional area of ​​the channel to form a release space for the prostate stent 22. At the same time, the buffer layer provided on the inner wall of the expansion member can effectively absorb the impact force when the prostate stent 22 pops open. In addition, the arc contour design of the two expansion members ensures that the tissue contact surface can be smoothly transitioned when expanded, and can be restored to the initial compact shape when contracted and reset to facilitate the removal of the device.

[0040] At least one of the first expansion member 5 and the second expansion member 6 has a guide boss structure 8 on its inner wall. The guide boss structure 8 is located on the path of the inner tube 4 as it travels towards the target tissue area of ​​the human body, so that it can be supported by the inner tube 4 to keep the first expansion member 5 and the second expansion member 6 away from each other. The above design can prevent the prostate stent 22 from causing impact damage to surrounding tissues during its deployment. The guide boss structure 8 is disposed on the inner wall of the expansion channel 3 on the side close to the target tissue area of ​​the human body along the travel direction of the inner tube 4. The guide boss structure 8 is integrally formed with the inner wall of the expansion assembly 2 or detachably connected. The radial height of the guide boss structure 8 is set according to the different dimensions of the prostate stent 22 before and after release. Preferably, the guide boss structure 8 and the expansion component 2 form a relatively sliding connection component through a sliding groove or threaded adjustment mechanism. The bottom of the guide boss structure 8 is provided with a slider that cooperates with the axial slide rail on the inner wall of the expansion component, or the radial height can be adjusted by rotating the threaded sleeve. This design allows the surgeon to adjust the radial protrusion height of the guide boss structure 8 in real time before or during the operation according to the different size specifications and expansion force requirements of the prostate stent 22, thereby accurately controlling the final expansion diameter of the expansion channel 3 and maintaining the stability of the overall structure supporting the expansion component 2.

[0041] During operation, as the inner tube 4 moves forward, its front end contacts the guide boss structure 8, converting the axial thrust into a radial expansion force. This forces the first expansion member 5 and the second expansion member 6 to rotate around the hinge point and move away from each other, thereby achieving the gradual unfolding of the expansion channel 3. The tilt angle and height of the guide boss structure 8 are precisely calculated to ensure the smooth passage of the inner tube 4 and to provide sufficient leverage during the stent release phase to achieve controllable expansion. This structural design makes the expansion process more stable and controllable, avoiding sudden mechanical impact on surrounding tissues.

[0042] The guide boss structure 8 is located at the end of the expansion channel 3 furthest from the human body. The guide boss structure 8 includes a guide ramp 9, which is located at the end of the guide boss structure 8 furthest from the target tissue area of ​​the human body. The guide boss structure 8 is located at the proximal end of the expansion channel 3 (the end furthest from the target tissue area of ​​the human body), and its main body is a sloping protrusion. At the proximal end, there is a guide ramp 9 with a specific angle, which forms an angle of a certain degree with the direction of travel of the inner tube 4. During dynamic operation, when the inner tube 4 advances forward to contact the guide ramp 9, the axial thrust is more efficiently converted into a radial component force through the guide ramp 9, which pushes the first expansion member 5 and the second expansion member 6 to safely rotate and unfold around the distal hinge point at a certain speed. As the inner tube 4 continues to advance, the cross-sectional area of ​​the expansion channel 3 increases linearly until it is fully unfolded. In practice, the operator first confirms the target position through the image positioning device, and then pushes the inner tube 4 at a constant speed so that the front end of the inner tube 4 contacts the guide slope 9 and the guide boss structure 8 in sequence. Symmetrical expansion is achieved through mechanical linkage, and the guide boss structure 8 maintains the stability of the angle between the first expansion member 5 and the second expansion member 6, creating a stable and sufficient space for the release of the prostate stent 22.

[0043] The inner tube 4 has a positioning protrusion 10 on its outer wall near the target tissue area. This positioning protrusion 10 serves as the prostate stent abutment 11, and its outer wall has an anti-slip structure 12 for abutting against the prostate stent 22 and the guide protrusion structure 8. The distal outer wall of the inner tube 4 has an annular positioning protrusion 10 (which can also be a single or multiple protrusions 17, such as non-annular limiting protrusions). The end face of this protrusion near the tissue serves as the prostate stent abutment 11. The diameter of this end face is 1.2-1.5 times larger than the minimum compressible diameter of the prostate stent 22, and its surface has staggered micro-convex anti-slip textures (or an elastic silicone anti-slip layer). The axial position of the positioning protrusion 10 corresponds to that of the guide protrusion structure 8, and their radial heights are appropriately matched. During operation, when the inner tube 4 is pushed forward so that the positioning protrusion 10 contacts the prostate stent 22, the anti-slip structure 12 prevents the prostate stent 22 from accidentally slipping out. Simultaneously, the rear end of the prostate stent 22 contacts the guide protrusion, forming a double fixation. As the tube continues to advance, when the positioning protrusion 10 interacts with the guide ramp 9 and the guide protrusion structure 8, the anti-slip structure 12 maintains the pre-compressed state of the stent through friction. Furthermore, the anti-slip structure 12 effectively prevents the positioning protrusion 10 from sliding too quickly and pushing the prostate stent 22 out of the target tissue area, allowing the positioning protrusion 10 to smoothly push the prostate stent 22 into the expansion channel 3. Specifically, the compressed stent is first fitted onto the positioning protrusion 10, where the anti-slip texture generates a certain amount of static friction. During the procedure, the inner tube 4 is pushed under image guidance. When the positioning protrusion 10 moves to the target position, the front end of the prostate stent 22 has entered the expansion area, at which point the anti-slip structure 12 still maintains axial constraint. After the prostate stent 22 partially unfolds and generates radial force, it is further advanced a certain distance to completely detach the contact end from the prostate stent 22, completing precise release.

[0044] See Figure 3The end of the positioning boss 10 away from the prostate stent abutment end 11 is the retraction linkage end 13 of the expansion component 2. The guide boss structure 8 can slide down to the axial side of the retraction linkage end 13 and abut against it. The end of the positioning boss 10 away from the target tissue area of ​​the human body is provided with the retraction linkage end 13, which has an axially extending receiving surface; the guide boss structure 8 is located at the starting position of the forward path of the retraction linkage end 13. During operation, when the outer tube 1 is retracted after the prostate stent 22 is released, the guide boss structure 8 slides along the outer wall of the positioning boss 10 until it contacts the retraction linkage end 13. Due to the axial height difference between the positioning boss 10 and the inner tube 4, a cavity is formed at the retraction linkage end 13 away from the target tissue area. The guide boss structure 8 slides along the cavity on the outer wall of the positioning boss 10 until it contacts the retraction linkage end 13. Under the action of the natural retraction force of the human tissue, the guide boss structure 8 is pushed into the cavity, forcing the first expansion member 5 and the second expansion member 6 to rotate and retract around the hinge point. At this time, the expansion component 2 changes from an expanded state to a contracted state. At this time, the retraction linkage end 13 forms a mechanical stop. The retraction force is transmitted through the bearing surface formed by the guide boss structure 8 and the retraction linkage end 13 of the positioning boss 10 and is evenly distributed to the entire expansion component 2. Since the expansion component 2 is connected to the outer tube 1, it drives the outer tube 1 to move in tandem, realizing the synchronous retraction of the inner tube 4, the outer tube 1, and the expansion component 2. This design ensures that the prostate stent 22 is not disturbed during device withdrawal, while also achieving uniform release and synchronous retraction of tissue pressure during device retraction. In practice, first, the prostate stent 22 is fully released and deployed in the target tissue area. The operator retracts the outer tube 1 at a constant speed. At this time, the guide boss structure 8 slides along the outer wall of the positioning boss 10 into the receiving cavity. When it contacts the receiving surface of the retraction linkage end 13, the guide boss structure 8 is pressed into the receiving cavity under the natural retraction force of the human tissue, forcing the first expansion member 5 and the second expansion member 6 to rotate and retract around the hinge point. Subsequently, the operator pulls the inner tube 4. Since the inner tube 4, outer tube 1, and expansion component 2 abut against the guide boss structure 8 through the retraction linkage end 13, a synchronous retraction structure is achieved. The three components retract synchronously, ensuring that the prostate stent 22 is not disturbed. Finally, the entire device is completely withdrawn through the cavity.

[0045] The hinge structure 7 is connected to a torsion spring 14. One end of the torsion spring 14 elastically abuts against the first expansion member 5, and the other end of the torsion spring 14 elastically abuts against the second expansion member 6. The torsion spring 14 has a tendency to drive the first expansion member 5 and the second expansion member 6 to move closer together. The hinge structure 7 has a built-in precision torsion spring 14 mechanism, whose helical central axis is arranged coaxially with the hinge point, and the torsion arms extending at both ends elastically abut against the inner walls of the first expansion member 5 and the second expansion member 6, respectively. The core function of the torsion spring 14 is manifested in three key stages: In the delivery stage (closed state), the preload torque of the torsion spring 14 maintains the tight fit of the two expansion components, ensuring that the expansion channel 3 maintains its minimum diameter; in the release stage, when the inner tube 4 pushes against the guide boss structure 8, the torsion spring 14 gradually deforms (rotates the angle to buffer the impact force of the expansion components' unfolding), allowing the channel diameter to smoothly expand to the expanded state of the expansion component 2 at a certain rate; in the retraction stage, the elastic potential energy stored in the torsion spring 14 actively drives the two expansion components to reset, and in conjunction with the mechanical limit of the retraction linkage end 13, realizes the rapid transition of the device from the expanded state to the closed state. The combination design of the torsion spring 14 and the hinge structure 7 can effectively prevent the prostate stent 22 from causing impact damage to surrounding tissues during the unfolding process; at the same time, in the retraction stage, the restoring force of the torsion spring 14 can actively assist the expansion component 2 in contraction, ensuring that the device is smoothly withdrawn without interfering with the implanted prostate stent 22.

[0046] One of the first expansion member 5 and the second expansion member 6 is provided with a magnet 15, and the other is provided with a magnetic element 16. The magnet 15 and the magnetic element 16 are attracted to each other. The first expansion member 5 and the second expansion member 6 adopt a magnetically assisted closure design, wherein the first expansion member 5 is embedded with a permanent magnet 15, and the second expansion member 6 is provided with a soft magnetic alloy element at a corresponding position. When the expansion assembly 2 needs to be closed, the magnet 15 and the magnetic element 16 generate the required attraction force within a certain effective working distance. This magnetic force, together with the elastic restoring force of the torsion spring 14, forms a double closure mechanism, which effectively avoids pinching tissue and provides additional holding force in the fully closed position to prevent accidental unfolding during transportation.

[0047] The expansion component 2 also includes a limiting structure, which includes a protruding structure 17 and a recessed structure 18 that cooperate with each other. The protruding structure 17 is located at the connecting end face of the first expansion member 5; the recessed structure 18 is located at the connecting end face of the second expansion member 6. A buffer structure is provided at the distal ends of the first expansion member 5 and the second expansion member 6. The buffer structure includes a first tapering structure 19 and a second tapering structure 20. The cross-sectional dimension of the first tapering structure 19 gradually decreases away from the target tissue area of ​​the human body; the cross-sectional dimension of the second tapering structure 20 gradually decreases away from the target tissue area of ​​the human body. The first tapering structure 19 and the second tapering structure 20 are correspondingly provided. This structure consists of the protruding structure 17 located at the connecting end face of the first expansion member 5 and the recessed structure 18 at the corresponding position of the second expansion member 6. When the two are fitted together, they form a suitable interference fit tolerance. The buffer structure provided at the distal ends of the first expansion member 5 and the second expansion member 6 includes the cooperating first tapering structure 19 and the second tapering structure 20. The first tapering structure 19 and the second tapering structure 20 adopt a tapered arc surface design. When the prostate stent 22 is released, the buffer structure can guide the unfolding force to be dispersed at a certain angle, effectively reducing the tissue contact pressure. At the same time, the rounded corner treatment at the tapered end avoids scratching the mucosal tissue.

[0048] At least one of the interiors of the first expansion member 5 and the second expansion member 6 is provided with a release guide structure 21. The release guide structure 21 extends axially along the first expansion member 5 or the second expansion member 6. The release guide structure 21 is located at one end of the guide boss structure 8 near the target tissue area of ​​the human body, and the side of the release guide structure 21 facing the expansion channel 3 extends along the end near the target tissue area of ​​the human body. The release guide structure 21 is used to guide the prostate stent 22. The release guide structure 21 is located in the transition area between the guide boss structure 8 and the buffer structure. It preferably adopts an arc surface design connected to the guide boss, and its surface has anti-roll texture and forms a continuous and smooth guide surface. When the outer tube 1 is retracted, this structure ensures that the protruding part of the guide buffer structure maintains a safe distance from the prostate stent 22. At the same time, through the synergistic effect of the arc surface design and the overall tilt design, it prevents the prostate stent 22 from rolling circumferentially and resists gravity slippage, so that the stent always maintains a stable position during the release and device retraction process, while completely avoiding mechanical interference of the retraction component to the released stent. The overall tilt design of this structure may interfere with other components during the contraction of the expansion component 2, thus affecting the contraction of the expansion component 2. Preferably, the release guide structure 21 is connected to the guide boss structure 8 through a hinge mechanism with a torsion spring 14. The two ends of the torsion spring 14 elastically abut against the side wall of the guide boss structure 8 and the release guide structure 21, respectively, and the two maintain a certain unfolding angle when the expansion component 2 is in the expanded state. When the expansion component 2 retracts, as the first expansion member 5 and the second expansion member 6 approach each other, the release guide structure 21 is subjected to force through the contact between its end and the inner wall of the expansion channel 3 or other components, which drives the torsion spring 14 to gradually roll back, so that the main body of the release guide structure 21 is retracted and finally completely retracted into the storage groove of the inner wall of the expansion component 2, realizing precise control of the retraction trajectory, which not only avoids the buffer structure from interfering with the released prostate stent 22, but also ensures that the overall outer diameter of the device retracts to the initial delivery state.

[0049] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of those different embodiments or examples.

[0050] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "a plurality of" means two or more, unless otherwise explicitly specified.

[0051] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various variations or substitutions within the technical scope disclosed in this application, and these should all be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. An auxiliary device for assisting the placement of a prostatic stent, characterized in that, The utility model relates to a kind of medical devices, including: Outer tube (1), the outer tube (1) has hollow cavity through and through; Expansion assembly (2), the expansion assembly (2) is connected with the outer tube (1), the expansion assembly (2) is used to prop open the tissue of human target tissue area, the expansion assembly (2) is equipped with expansion passage (3);The passage entrance of the expansion passage (3) is connected with the outlet of the hollow cavity of the outer tube (1);The expansion assembly (2) can be deformed, to expand or reduce the cross-sectional area of the expansion passage (3), the cross-sectional area of the expansion passage (3) is larger than the cross-sectional area of the hollow cavity after expansion, the inner wall of the expansion passage (3) is used to stop the prostatic stent (22) when being bounced; Inner tube (4), the inner tube (4) is set in the hollow cavity of the outer tube (1), and it extends along the length direction of the outer tube (1), the inner tube (4) can be axially relatively moved along the hollow cavity;The inner tube (4) is used to push the prostatic stent (22) to the expansion passage (3).

2. The device according to claim 1, wherein The expansion assembly (2) further includes first expansion piece (5) and second expansion piece (6), the first expansion piece (5) and second expansion piece (6) are arc shape structure, the first expansion piece (5) and the second expansion piece (6) are mutually hinged by hinged structure (7) on the end away from human target tissue area, and are jointly enclosed the expansion passage (3).

3. The device according to claim 2, wherein The inner wall of at least one of the first expansion piece (5) and second expansion piece (6) is equipped with guide boss structure (8), the guide boss structure (8) is located on the path of the inner tube (4) to approach human target tissue area, so that the first expansion piece (5) and second expansion piece (6) can be mutually away from by being supported by the inner tube (4).

4. The device according to claim 3, wherein The guide boss structure (8) is located on the end of the expansion passage (3) away from human target tissue area;The guide boss structure (8) includes guide inclined plane (9), and the guide inclined plane (9) is arranged on the end of the guide boss structure (8) away from human target tissue area.

5. The device of claim 3, wherein the device is configured to be inserted into the urethra and to be positioned in the urethra such that the device is positioned between the urethral wall and the prosthesis. The outer wall of the end of the inner tube (4) close to human target tissue area is equipped with positioning boss (10), the end of the positioning boss (10) close to human target tissue area is prostatic stent abutting end (11), the outer side wall of the prostatic stent abutting end (11) is equipped with anti-skid structure (12), and the anti-skid structure (12) is used to abut prostatic stent (22) and the guide boss structure (8).

6. The device of claim 5, wherein the device is configured to be inserted into the urethra and to be positioned in the urethra such that the device is positioned between the urethral wall and the prosthesis. The end of the positioning boss (10) away from the prostatic stent abutting end (11) is the withdrawal linkage end (13) of expansion assembly (2), the guide boss structure (8) can slide to the axial side of the withdrawal linkage end (13), and abuts with the withdrawal linkage end (13).

7. The device of claim 2, wherein, The hinged structure (7) is connected with a torsion spring (14), one end of the torsion spring (14) elastically abuts against the first expansion member (5), the other end of the torsion spring (14) elastically abuts against the second expansion member (6), and the torsion spring (14) has a movement tendency to drive the first expansion member (5) and the second expansion member (6) to approach each other.

8. The device according to claim 2 or 7, wherein One of the first expansion member (5) and the second expansion member (6) is provided with a magnet (15), and the other is provided with a magnetic element (16), and the magnet (15) and the magnetic element (16) are attracted to each other.

9. The device of claim 2, wherein, The expansion assembly (2) further comprises a limiting structure, the limiting structure comprises a protruding structure (17) and a recessed structure (18) arranged in cooperation with each other; the protruding structure (17) is arranged at the connecting end face of the first expansion member (5); the recessed structure (18) is arranged at the connecting end face of the second expansion member (6). The distal end of the first expansion member (5) and the second expansion member (6) is provided with a buffer structure, the buffer structure comprises a first tapered structure (19) and a second tapered structure (20); the cross-sectional size of the first tapered structure (19) gradually decreases away from the target tissue region of the human body; the cross-sectional size of the second tapered structure (20) gradually decreases away from the target tissue region of the human body, and the first tapered structure (19) and the second tapered structure (20) are correspondingly arranged.

10. The device of claim 9, wherein the device is configured to be used in conjunction with a prostatic stent. At least one of the inside of the first expansion member (5) and the inside of the second expansion member (6) is provided with a release guide structure (21); the release guide structure (21) extends axially along the first expansion member (5) or the second expansion member (6); the release guide structure (21) is arranged at one end of the guide boss structure (8) close to the target tissue region of the human body, and the side of the release guide structure (21) facing the expansion channel (3) extends along the end close to the target tissue region of the human body, and the release guide structure (21) is used for guiding the prostate stent (22).

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