Bionic structure for minimally invasive surgery and preparation method

Abstract

The invention relates to a bionic structure for minimally invasive surgery and a preparation method, the bionic structure for minimally invasive surgery comprises a variable-diameter sheath core and a flexible sheath tube, the variable-diameter sheath core comprises a sheath core main body, a guide wire channel is arranged in the sheath core main body, one end of the sheath core main body is sleeved with a linear balloon, and the linear balloon is arranged in the sheath core main body. The balloon is communicated with a balloon filling channel; the flexible sheath tube is arranged outside the linear balloon in a sleeving mode, the hardness of the imbedding end of the flexible sheath tube is smaller than that of the operating end of the flexible sheath tube, and when the linear balloon is full, the linear balloon abuts against the inner wall of the flexible sheath tube, so that the sheath core body, the linear balloon and the flexible sheath tube are fixed into a whole.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of medical devices, in particular to a bionic structure for minimally invasive surgery and a preparation method thereof. BACKGROUND

[0002] At present, in urological surgery, a ureteral guide sheath needs to be placed in the ureter to realize the guidance of a ureteral soft mirror and the real-time flow of irrigation liquid, which is a key instrument for creating a surgical channel, protecting the cavity tissue and guiding the endoscope.

[0003] In related technologies, the ureteral guide sheath is composed of a sheath core and a sheath tube. In order to place the sheath smoothly, the existing sheath core and sheath tube have high rigidity and low softness. The sheath tube may cause high tension or direct tearing to the curved or narrow parts of the ureter during the placement process, which has a high risk of surgical injury. At the same time, the high rigidity and the high tension caused by the ureter may cause ischemic injury to the ureter, which may cause serious long-term complications.

[0004] Therefore, it is necessary to design a new bionic structure for minimally invasive surgery to overcome the above problems. SUMMARY

[0005] The present application provides a bionic structure for minimally invasive surgery and a preparation method, which can solve the technical problems of the existing sheath core and flexible sheath tube with high rigidity and low softness in related technologies, and the flexible sheath tube may cause tearing to the curved or narrow parts of the ureter during the placement process, which has a high risk of surgical injury.

[0006] In a first aspect, the embodiments of the present application provide a bionic structure for minimally invasive surgery, which comprises a variable-diameter sheath core and a flexible sheath tube. The variable-diameter sheath core comprises a sheath core body, a guide wire channel is arranged in the sheath core body, a linear balloon is arranged at one end of the sheath core body, and the linear balloon is connected with a balloon inflation channel. The flexible sheath tube is arranged outside the linear balloon, the hardness of the placement end of the flexible sheath tube is less than the hardness of the operation end of the flexible sheath tube, and when the linear balloon is inflated, the linear balloon presses against the inner wall of the flexible sheath tube, so that the sheath core body, the linear balloon and the flexible sheath tube are fixed as a whole.

[0007] The linear balloon is fitted onto the distal end of the sheath core body, and the sheath core body and the linear balloon are welded together to form a single unit. The variable-diameter sheath core can be bent freely in its natural state, but it does not have independent pushing capability. The hardness of the insertion end of the flexible sheath is less than that of the operating end. The flexible sheath can be bent freely in its natural state, but it does not have independent pushing capability and its support force is relatively small, making it unable to push independently. The balloon inflation channel is connected to a balloon inflation tube. When air or liquid is injected into the balloon inflation channel, the linear balloon expands. The outer diameter of the linear balloon is larger than the inner diameter of the flexible sheath, and the linear balloon interacts with the inner wall of the flexible sheath. With sufficient positive pressure, the linear balloon and the flexible sheath will not experience relative displacement, enabling synchronous advancement of the variable-diameter sheath core and the flexible sheath. The linear balloon is inflated to press against the flexible sheath, ensuring the flexibility of the flexible sheath while increasing the rigidity of the insertion end of the biomimetic structure for minimally invasive surgery. This biomimetic structure can serve as a ureteral guide sheath, facilitating its insertion into curved or narrow sections of the ureter and reducing tension. Exemplarily, the total length of the sheath core body can be set to 300-800 mm, the tip of the sheath core body is tapered, the length of the tip is set to 10-30 mm, and the diameter of the sheath core body is set to 0.2-3 mm.

[0008] In conjunction with the first aspect, in one embodiment, the flexible sheath includes an operating section and an insertion section connected to each other, wherein the operating section has equal hardness at all points, and the hardness of the insertion section gradually decreases from its connection with the operating section toward the direction away from the operating section.

[0009] The operating segment is a flexible sheath between points a and b, with a length of L1. The insertion segment is a flexible sheath between points b and c, with a length of L2. During the insertion of the biomimetic structure into the ureter in minimally invasive surgery, the operating segment is a rigid segment located in the urethral and bladder portions of the ureter, while the insertion segment is a gradually softening segment located in the ureteral portion. The hardness of the operating segment is greater than that of the insertion segment, and the hardness of the insertion segment is gradually distributed. The tip of the insertion segment furthest from the operating segment has the lowest hardness, allowing the front end of the flexible sheath to adaptively bend the cavity when the linear balloon is inflated. This facilitates the pushing of the flexible sheath into the ureter at a larger bending angle. Exemplarily, the hardness of the operating segment is set to Shore 55D, and the hardness of the insertion segment is set to Shore 15-25D.

[0010] In conjunction with the first aspect, in one embodiment, the flexible sheath includes an inner layer, a middle layer, and an outer layer connected from the inside out, the middle layer being configured as a braided spring layer made of metal alloy wire, and the braiding density of the braided spring layer in the insertion section gradually decreasing from the connection point with the operating section toward the direction away from the operating section.

[0011] The braided spring layer is made of titanium alloy wire, stainless steel wire, or other shape memory alloy wire. The braiding density of the braided spring layer in the operating section is greater than that in the insertion section. The braiding density of the braided spring layer in the insertion section gradually decreases along the length of the flexible sheath. The greater the braiding density of the braided spring layer, the greater its hardness. The surface of the braided spring layer is designed with a microwave texture, which gives the braided spring layer both softness and support.

[0012] In conjunction with the first aspect, in one embodiment, the diameter of the metal alloy wire is set to 0.01~0.4 mm.

[0013] The diameter of the metal alloy wire can be set to 0.01~0.4 mm, and the wall thickness of the braided spring layer is set to 0.01~0.4 mm accordingly, so as to minimize the space occupied by the flexible sheath, avoid the ureter from seizing the flexible sheath, and avoid traction damage during sheath removal.

[0014] In conjunction with the first aspect, in one embodiment, the inner layer is made of PP and the outer layer is made of PTFE.

[0015] The inner layer is made of polymer materials such as PP, LDPE, PTFE, PEPAX, TPU, PA, PU, ​​PEEK, or PVC to make the inner layer lubricating, while the outer layer is made of polymer materials such as PTFE, PEPAX, TPU, PA, PU, ​​PEEK, or PVC to make the outer layer elastic.

[0016] In conjunction with the first aspect, in one embodiment, the sheath core body is made of PTFE, and the linear balloon is made of latex.

[0017] The sheath core body can be made of polymer materials such as PTFE, PEPAX, TPU, PA, PU, ​​PEEK or PVC, and the linear balloon is made of medical latex material.

[0018] In conjunction with the first aspect, in one embodiment, the linear balloon is configured as a cord-like balloon.

[0019] The linear balloon is adapted to the inner lumen of the flexible sheath. Exemplarily, the linear balloon is located in the middle of the flexible sheath, measuring 280-780 mm. The length of the linear balloon is adjusted according to the actual surgical channel length.

[0020] Secondly, embodiments of this application provide a method for preparing a biomimetic structure for minimally invasive surgery, which includes the following steps: A linear balloon is fixed to one end of the sheath core body to form a variable diameter sheath core; A variable-diameter sheath core is pushed into a flexible sheath tube to form a biomimetic structure for minimally invasive surgery.

[0021] The linear balloon is sleeved at the distal end of the sheath core body, and the sheath core body and the linear balloon are welded together to form a single unit. The hardness of the insertion end of the flexible sheath is less than that of the operating end of the flexible sheath. The flexible sheath lacks pushability. When the linear balloon is inflated, the linear balloon and the inner wall of the flexible sheath generate sufficient positive pressure, and the linear balloon and the flexible sheath will not undergo relative displacement, realizing the synchronous push of the variable diameter sheath core and the flexible sheath. The expansion and inflation of the linear balloon presses the linear balloon against the flexible sheath, ensuring the flexibility of the flexible sheath while improving the rigidity of the insertion end of the biomimetic structure for minimally invasive surgery, facilitating its insertion into the curved or narrow parts of the ureter. After pushability is completed, the linear balloon depressurizes and contracts, withdrawing the variable diameter sheath core to form a flexible surgical channel.

[0022] In conjunction with the second aspect, in one embodiment, fixing the linear balloon to one end of the sheath core body to form a variable-diameter sheath core includes: The sheath core body is extruded using a tube extrusion process, and a linear balloon is welded to one end of the sheath core body to form a variable diameter sheath core.

[0023] The process involves extruding the sheath core body using an extruder, then thermally welding the linear balloon to the distal end of the sheath core body to form the variable diameter sheath core. The proximal end of the sheath core body serves as the handheld end of the variable diameter sheath core.

[0024] In conjunction with the second aspect, in one embodiment, before fixing the linear balloon to one end of the sheath core body to form a variable-diameter sheath core, the following steps are included: An inner layer is wrapped around the outer core, and a braided spring layer is formed by winding metal alloy wire around the inner layer. An outer layer is then wrapped around the braided spring layer. The core, inner layer, braided spring layer and outer layer are subjected to thermorheological treatment to heat-melt the inner layer, braided spring layer and outer layer into one piece, wherein the heating temperature of the thermorheological treatment is set to 150~250℃; The shaft core is extracted to form a flexible sheath.

[0025] In an exemplary manner, the shaft core is first passed through the inner layer, and then titanium alloy wire is wound around the shaft core with PP film in place using a wire winding machine to form the braided spring layer. The braiding density of the braided spring layer gradually decreases from the connection point with the operating section towards the direction away from the operating section. The braided spring layer forms a tightly and orderly arranged tubular body at the operating end of the flexible sheath, and a sparsely and orderly arranged tubular body at the insertion end of the flexible sheath. Then, a heat-shrinkable tube is fitted over the braided spring layer to form the outer layer. The shaft core, which is fitted with the inner layer, the braided spring layer, and the outer layer, is placed in an oven and heated to 200°C. The inner layer and the outer layer are fused together to form a composite tube. The shaft core is then removed to form the flexible sheath.

[0026] The beneficial effects of the technical solutions provided in this application include: By fitting a linear balloon at one end of the sheath core to form a variable-diameter sheath core, and then fitting a flexible sheath over the linear balloon, the insertion end of the flexible sheath has a lower hardness than the operating end. The linear balloon is expanded and inflated to press against the flexible sheath, ensuring the flexibility of the flexible sheath while improving the rigidity of the insertion end of the biomimetic structure for minimally invasive surgery. This allows the flexible structure to be inserted into the curved or narrowed parts of the ureter, solving the technical problems of existing sheath cores and sheaths having high rigidity and low flexibility, which can cause tearing of the curved or narrowed parts of the ureter during insertion, resulting in a high risk of surgical injury. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 A schematic diagram of a biomimetic structure for minimally invasive surgery provided in an embodiment of this application; Figure 2 This is a schematic diagram of the variable diameter sheath core before filling, provided in an embodiment of this application. Figure 3 This is a schematic diagram of the variable diameter sheath core after being filled, provided in an embodiment of this application. Figure 4 A schematic diagram of the operation segment and insertion segment provided in the embodiments of this application; Figure 5 A schematic diagram of the variable diameter sheath core in its natural state, as provided in an embodiment of this application; Figure 6This is a schematic diagram of the flexible sheath provided in the embodiment of this application in its natural state.

[0029] In the figure: 1. Variable diameter sheath core; 11. Sheath core body; 12. Guidewire channel; 13. Linear balloon; 14. Balloon inflation channel; 2. Flexible sheath; 21. Operating section; 22. Insertion section. Detailed Implementation

[0030] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0031] This application provides a biomimetic structure and preparation method for minimally invasive surgery, which can solve the technical problems of existing sheath cores and flexible sheaths having high rigidity and low flexibility, and the flexible sheaths causing tearing of the curved or narrow parts of the ureter during insertion, resulting in a high risk of surgical damage.

[0032] See Figures 1-3 As shown in the figure, this application provides a biomimetic structure for minimally invasive surgery, which includes: a variable diameter sheath core 1 and a flexible sheath tube 2. The variable diameter sheath core 1 includes a sheath core body 11, a guide wire channel 12 is provided inside the sheath core body 11, and a linear balloon 13 is sleeved on one end of the sheath core body 11. The linear balloon 13 is connected to a balloon inflation channel 14. The flexible sheath tube 2 is sleeved on the linear balloon 13. The hardness of the insertion end of the flexible sheath tube 2 is less than the hardness of the operating end of the flexible sheath tube 2. When the linear balloon 13 is inflated, the linear balloon 13 presses against the inner wall of the flexible sheath tube 2, so that the sheath core body 11, the linear balloon 13 and the flexible sheath tube 2 are fixed together.

[0033] In this embodiment, the linear balloon 13 is sleeved on the distal end of the sheath core body 11, and the sheath core body 11 and the linear balloon 13 are welded together to form a single unit, such as... Figure 5 As shown, the variable diameter sheath core 1 can be bent freely in its natural state. The variable diameter sheath core 1 does not have independent pushing capability. The hardness of the insertion end of the flexible sheath tube 2 is less than the hardness of the operating end of the flexible sheath tube 2. Figure 6As shown, the flexible sheath 2 can be bent freely in its natural state. The flexible sheath 2 does not have independent pushing capability and has relatively low support force, making it unable to push independently. The balloon inflation channel 14 is connected to a balloon inflation tube. When air or liquid is injected into the balloon inflation channel 14, the linear balloon 13 expands. The outer diameter of the linear balloon 13 is larger than the inner diameter of the flexible sheath 2. The linear balloon 13 and the inner wall of the flexible sheath 2 generate sufficient positive pressure, preventing relative displacement between the linear balloon 13 and the flexible sheath 2, thus achieving synchronous pushing of the variable diameter sheath core 1 and the flexible sheath 2. The linear balloon 13 is inflated and presses against the flexible sheath 2, ensuring the flexibility of the flexible sheath 2 while increasing the rigidity of the insertion end of the biomimetic structure for minimally invasive surgery. The biomimetic structure for minimally invasive surgery can serve as a ureteral guide sheath, facilitating its insertion into curved or narrowed parts of the ureter and reducing tension. Exemplarily, the total length of the sheath core body 11 can be set to 300~800 mm, the tip of the sheath core body 11 is set to be conical, the length of the tip of the sheath core body 11 is set to 10~30 mm, and the diameter of the sheath core body 11 is set to 0.2~3 mm.

[0034] In other embodiments, the biomimetic structure for minimally invasive surgery can be used as a vascular intervention sheath in cardiovascular minimally invasive surgery. The biomimetic structure for minimally invasive surgery can also be used for percutaneous liver puncture, percutaneous nephrolithotomy, or other treatments that require serpentine bends within the lumen to reduce damage to the lumen from the sheath.

[0035] This embodiment forms the variable-diameter sheath core 1 by sleeved with the linear balloon 13 at one end of the sheath core body 11, and the flexible sheath tube 2 is sleeved on the linear balloon 13. The hardness of the insertion end of the flexible sheath tube 2 is less than that of the operating end of the flexible sheath tube 2. The linear balloon 13 is expanded and filled to press the linear balloon 13 against the flexible sheath tube 2, ensuring the flexibility of the flexible sheath tube 2 while improving the rigidity of the insertion end of the biomimetic structure for minimally invasive surgery. This allows the flexible structure to be inserted into the curved or narrow parts of the ureter, solving the technical problems of existing sheath cores and sheath tubes in related technologies, which have high rigidity and low flexibility, and the sheath tube may tear the curved or narrow parts of the ureter during insertion, resulting in a high risk of surgical damage.

[0036] Further, see Figure 1 and Figure 4 As shown, in some embodiments, the flexible sheath 2 includes an operating section 21 and an insertion section 22 connected to each other. The operating section 21 has the same hardness at all points, and the hardness of the insertion section 22 gradually decreases from the connection point with the operating section 21 toward the direction away from the operating section 21.

[0037] In this embodiment, the operating segment 21 is a flexible sheath 2 between point a and point b, and the length of the operating segment 21 is set to L1. The insertion segment 22 is a flexible sheath 2 between point b and point c, and the length of the insertion segment 22 is set to L2. During the insertion of the biomimetic structure into the ureter in the minimally invasive surgery, the operating segment 21 is set as a rigid segment, located in the urethral and bladder portions of the ureter. The insertion segment 22 is a gradually softening segment, located in the ureteral portion. The hardness of the operating segment 21 is greater than that of the insertion segment 22, and the hardness of the insertion segment 22 is gradually distributed. The hardness of the insertion segment 22 furthest from the operating segment 21 is the smallest, so that the front end of the flexible sheath 2 adaptively bends the cavity when the linear balloon 13 is inflated, facilitating the pushing of the flexible sheath 2 into the ureter at a larger bending angle. Exemplarily, the hardness of the operating segment 21 is set to Shore 55D, and the hardness of the insertion segment 22 is set to Shore 15~25D.

[0038] Further, see Figure 1 , Figure 4 and Figure 6 As shown, in some embodiments, the flexible sheath 2 includes an inner layer, a middle layer, and an outer layer connected from the inside out. The middle layer is configured as a braided spring layer, which is made of metal alloy wire. The braiding density of the braided spring layer in the insertion section 22 gradually decreases from the connection with the operating section 21 in the direction away from the operating section 21.

[0039] In this embodiment, the braided spring layer is made of titanium alloy wire, stainless steel wire, or other shape memory alloy wire. The braiding density of the braided spring layer in the operation section 21 is greater than that in the insertion section 22. The braiding density of the braided spring layer in the insertion section 22 gradually decreases along the length of the flexible sheath 2. The greater the braiding density of the braided spring layer, the greater the hardness of the braided spring layer. The surface of the braided spring layer adopts a microwave texture design, so that the braided spring layer has both softness and support.

[0040] Further, see Figure 1 , Figure 4 and Figure 6 As shown, in some embodiments, the diameter of the metal alloy wire is set to 0.01~0.4 mm.

[0041] In this embodiment, the diameter of the metal alloy wire can be set to 0.01~0.4 mm, and the wall thickness of the braided spring layer is set to 0.01~0.4 mm accordingly, so as to minimize the space occupied by the flexible sheath 2, avoid the ureter from locking the flexible sheath 2, and avoid traction damage during sheath removal.

[0042] Furthermore, in some embodiments, the inner layer is made of PP and the outer layer is made of PTFE.

[0043] In this embodiment, the inner layer is made of polymer materials such as PP (polypropylene), LDPE (polyethylene), PTFE (polytetrafluoroethylene), PEPAX, TPU (thermoplastic polyurethane rubber), PA, PU (polyurethane), PEEK (polyether ether ketone), or PVC (polyvinyl chloride) to make the inner layer lubricating, and the outer layer is made of polymer materials such as PTFE, PEPAX, TPU, PA, PU, ​​PEEK, or PVC to make the outer layer elastic.

[0044] Further, see Figures 1-3 As shown, in some embodiments, the sheath core body 11 is made of PTFE, and the linear balloon 13 is made of latex.

[0045] In this embodiment, the sheath core body 11 can be made of polymer materials such as PTFE, PEPAX, TPU, PA, PU, ​​PEEK or PVC, and the linear balloon 13 is made of medical latex material.

[0046] Further, see Figures 1-3 As shown, in some embodiments, the linear balloon 13 is configured as a cord-like balloon.

[0047] In this embodiment, the shape of the linear balloon 13 is adapted to the inner lumen of the flexible sheath 2. Exemplarily, the linear balloon 13 is located in the middle of the flexible sheath 2, and the length of the linear balloon 13 is set to 280~780 mm. The length of the linear balloon 13 is adjusted according to the actual surgical channel length.

[0048] This application provides a method for preparing a biomimetic structure for minimally invasive surgery, which includes the following steps: S1: Fix the linear balloon 13 to one end of the sheath core body 11 to form a variable diameter sheath core 1.

[0049] S2: Push the variable diameter sheath core 1 into the flexible sheath tube 2 to form a biomimetic structure for minimally invasive surgery.

[0050] In this embodiment, the linear balloon 13 is sleeved on the distal end of the sheath core body 11, and the sheath core body 11 and the linear balloon 13 are welded together to form a whole. The hardness of the insertion end of the flexible sheath 2 is less than that of the operating end of the flexible sheath 2. The flexible sheath 2 lacks pushability. When the linear balloon 13 is inflated, the linear balloon 13 and the inner wall of the flexible sheath 2 generate sufficient positive pressure, and the linear balloon 13 and the flexible sheath 2 will not have relative displacement, so as to realize the synchronous push of the variable diameter sheath core 1 and the flexible sheath 2. The linear balloon 13 is expanded and inflated to press the linear balloon 13 and the flexible sheath 2 together, ensuring the flexibility of the flexible sheath 2 while improving the rigidity of the insertion end of the biomimetic structure for minimally invasive surgery, which facilitates its insertion into the curved or narrow parts of the ureter. After the push is completed, the linear balloon 13 depressurizes and contracts, and the variable diameter sheath core 1 is withdrawn to form a flexible surgical channel.

[0051] Furthermore, in some embodiments, fixing the linear balloon 13 to one end of the sheath core body 11 to form a variable diameter sheath core 1 includes: The sheath core body 11 is extruded using a tube extrusion process, and a linear balloon 13 is welded to one end of the sheath core body 11 to form a variable diameter sheath core 1.

[0052] In this embodiment, the sheath core body 11 is extruded using an extruder, and the linear balloon 13 is thermally welded to the distal end of the sheath core body 11 to form the variable diameter sheath core 1. The proximal end of the sheath core body 11 serves as the handheld end of the variable diameter sheath core 1.

[0053] Furthermore, in some embodiments, before fixing the linear balloon 13 to one end of the sheath core body 11 to form the variable diameter sheath core 1, the following steps are included: S101: An inner layer is wrapped around the shaft core, a braided spring layer is formed by winding metal alloy wire around the inner layer, and an outer layer is wrapped around the braided spring layer.

[0054] S102: Perform thermorheological treatment on the shaft core, inner layer, braided spring layer and outer layer to heat-melt the inner layer, braided spring layer and outer layer into one piece, wherein the heating temperature of the thermorheological treatment is set to 150~250℃.

[0055] S103: Pull out the shaft core to form a flexible sheath 2.

[0056] In this embodiment, exemplary, the shaft core is first passed through the inner layer, and then titanium alloy wire is wound around the shaft core with PP film in place using a wire winding machine to form the braided spring layer. The braiding density of the braided spring layer gradually decreases from the connection point with the operating section 21 towards the direction away from the operating section 21. The braided spring layer forms a tightly and orderly arranged tubular body at the operating end of the flexible sheath 2, and a sparsely and orderly arranged tubular body at the insertion end of the flexible sheath 2. Then, a heat shrink tube is fitted over the braided spring layer to form the outer layer. The shaft core with the inner layer, the braided spring layer, and the outer layer is placed in an oven and heated to 200°C. The inner layer and the outer layer are fused together to form a composite tube. The shaft core is then pulled out to form the flexible sheath 2.

[0057] In the description of this application, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0058] It should be noted that in this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0059] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A biomimetic structure for minimally invasive surgery, characterized in that, It comprises: A variable diameter sheath core (1) comprising a sheath core body (11) provided with a guide wire channel (12) therein, one end of the sheath core body (11) being provided with a linear balloon (13), the linear balloon (13) being communicated with a balloon inflation channel (14); A flexible sheath tube (2) sleeved outside the linear balloon (13), the hardness of the insertion end of the flexible sheath tube (2) being less than that of the operation end of the flexible sheath tube (2), when the linear balloon (13) is inflated, the linear balloon (13) presses against the inner wall of the flexible sheath tube (2), so that the sheath core body (11), the linear balloon (13) and the flexible sheath tube (2) are fixed as a whole, Wherein the flexible sheath tube (2) comprises an operation section (21) and an insertion section (22) connected with each other, the hardness of the operation section (21) is equal everywhere, and the hardness of the insertion section (22) gradually decreases from the connection with the operation section (21) to the direction away from the operation section (21), The flexible sheath tube (2) comprises an inner layer, an intermediate layer and an outer layer sleeved from inside to outside, the intermediate layer is provided as a woven spring layer, the woven spring layer adopts metal alloy wires, and the weaving density of the woven spring layer in the insertion section (22) gradually decreases from the connection with the operation section (21) to the direction away from the operation section (21).

2. The biomimetic structure for minimally invasive surgery of claim 1, wherein, The diameter of the metal alloy wire is 0.01-0.4mm.

3. The biomimetic structure for minimally invasive surgery of claim 1, wherein, The inner layer adopts PP, and the outer layer adopts PTFE.

4. The biomimetic structure for minimally invasive surgery of claim 1, wherein, The sheath core body (11) adopts PTFE, and the linear balloon (13) adopts latex.

5. The minimally invasive surgical bionic structure of claim 1, wherein, The linear balloon (13) is provided as a cable-like balloon.

6. A method of producing a bionic structure for minimally invasive surgery as claimed in any one of claims 1 to 5, characterized in that, It comprises the following steps: Fixing the linear balloon (13) at one end of the sheath core body (11) to form a variable diameter sheath core (1); Pushing the variable diameter sheath core (1) into the flexible sheath tube (2) to form a bionic structure for minimally invasive surgery.

7. The production method according to claim 6, wherein The fixing of the linear balloon (13) at one end of the sheath core body (11) to form a variable diameter sheath core (1) comprises: Extruding the sheath core body (11) by a tube extrusion process, and welding the linear balloon (13) at one end of the sheath core body (11) to form a variable diameter sheath core (1).

8. The production method according to claim 6, wherein Before fixing the linear balloon (13) at one end of the sheath core body (11) to form a variable diameter sheath core (1), it comprises: Coating an inner layer outside the shaft core, winding metal alloy wires outside the inner layer to form a woven spring layer, and coating an outer layer outside the woven spring layer; Performing heat flow treatment on the shaft core, the inner layer, the woven spring layer and the outer layer to make the inner layer, the woven spring layer and the outer layer melt together, wherein the heating temperature of the heat flow is set to 150-250℃; Extracting the shaft core to form a flexible sheath tube (2).

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