Bending-controllable medical catheter and bending adjusting method

Abstract

The invention relates to a bending-controllable medical catheter and a bending adjusting method. Comprising a tube body, and the tube body is sequentially provided with a main body rigid section and an adjustable bending section from the near end to the far end; a bending control layer is arranged in the adjustable bending section, and the bending control layer is filled with hydrogel; a plurality of perfusion channels are arranged in the tube body from the main body rigid section and the adjustable bending section; at least part of the adjustable bending section has elastic deformation capacity, and the bending form of the adjustable bending section is controlled by injecting liquid into the bending control layer to adjust the hardness of the hydrogel; and a bending adjusting structure is arranged in the pipe body. Compared with the prior art, the medical catheter disclosed by the invention has the beneficial effects that the medical catheter is controlled to bend by utilizing the characteristic that the hydrogel absorbs water and is hardened, and the adjustable bending section can be kept in a bending state, so that the intervention operation of an operator is facilitated; the reversible property of water absorption and dehydration of the hydrogel is achieved, the hydrogel is pumped, the controllable bent section is reset, then the hydrogel is taken out from the target part, and the safety in the taking-out process is guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a controllable bending medical catheter and a bending adjustment method thereof. Background Art

[0002] Medical sheaths are used in minimally invasive interventional diagnostic and therapeutic surgeries to establish channels, deliver or retrieve instruments, deliver drugs, or remove body fluids. In clinical procedures, sheaths need to be adjusted to different shapes based on actual needs and differences in target vascular anatomical morphology.

[0003] The controllable bending medical catheter is an advanced medical device designed for complex cardiovascular surgery. It allows the operator to control the distal bending of the catheter through an external handle when intervening at the target site, thereby accurately navigating inside the target object and reaching the hard-to-reach heart or blood vessel area. This design greatly improves the accuracy and safety of the operation, reduces the operation time and damage to the patient's tissue.

[0004] Most of the existing adjustable sheaths use wire traction to achieve the purpose of bending, which is not only complicated in process and sacrifices the passage space in the sheath, but also can only achieve bending within a certain angle range in one plane. If the bending effect in three-dimensional space needs to be achieved, the number of pulling wires needs to be increased, which further increases the difficulty of the process. At the same time, it is often difficult to meet the use requirements of different vascular morphologies of the target object.

[0005] The Chinese invention patent with publication number CN113908404A discloses an adjustable sheath tube, which includes: a support tube segment and a bend-adjusting tube segment connected in sequence from the proximal end to the distal end; the support tube segment and the bend-adjusting tube segment are provided with a plurality of perfusion channels extending from the proximal end of the support tube segment to the distal end of the bend-adjusting tube segment, the proximal end of the perfusion channel is open and the distal end is closed; at least part of the bend-adjusting tube segment has elastic deformation capability, and the bending shape of the bend-adjusting tube segment can be controlled by adjusting the fluid pressure in the perfusion channel. The embodiment of the present invention controls the bending shape of the bend-adjusting tube segment by the fluid pressure in the perfusion channel, which is conducive to improving the controllability of the bending shape. At the same time, the structure is simple, easy to operate, and does not occupy the perfusion channel of the sheath tube.

[0006] However, the above bending adjustment principle controls the bending shape of the bending pipe section through fluid pressure, and the fluid pressure inside the different pipe body positions is different and cannot be maintained in a stable state, so the bending shape cannot be maintained at the initially set bending state. During operation, the constant changes in the bending shape of the pipe will bring great challenges to the operation and are not conducive to the smooth progress of the operation. Summary of the invention

[0007] In order to solve the above problems existing in the prior art, the present invention provides a controllable bending medical catheter and a bending adjustment method.

[0008] The above-mentioned problem of the present invention is solved by the following technical solutions: A controllable bending medical catheter comprises a tube body, wherein the tube body comprises a main rigid section and an adjustable bending section from the proximal end to the distal end; a bending control layer is arranged in the adjustable bending section, and the bending control layer is filled with hydrogel; The tube body is provided with a plurality of perfusion channels from the main rigid section and the adjustable bending section; At least part of the adjustable bending section has elastic deformation capability, and the bending shape of the adjustable bending section is controlled by injecting liquid into the bending control layer to adjust the hardness of the hydrogel; The tube body is provided with a bending adjustment structure.

[0009] The above technical solution is further configured as follows: the proximal end of the perfusion channel is open and the distal end is closed.

[0010] The above technical solution is further configured as follows: the adjustable bending section is made of a material with shape memory properties.

[0011] The above technical solution is further configured as follows: a bending adjustment channel is provided in the tube body, and the bending adjustment structure is arranged in the bending adjustment channel.

[0012] The above technical solution is further configured as follows: the bending adjustment structure is a bending adjustment pull wire, and the distal end of the bending adjustment pull wire is connected to the distal end of the tube body.

[0013] The above technical solution is further configured as follows: a hollow liner tube is also provided in the tube body, and the bending control layer is located between the liner tube and the inner wall of the tube body.

[0014] The above technical solution is further configured as follows: the inner lining pipe material is a composite material.

[0015] A method for adjusting the bending of a medical catheter, comprising the controllable bending medical catheter according to claim 5, wherein the bending adjustment structure is controlled by an operating handle, comprising the following steps: S1. Pull the operating handle, the operating handle pulls the bending adjustment wire, the far end of the bending adjustment wire pulls the far end of the adjustable bending section, and the adjustable bending section bends; S2, injecting liquid water into the bending control layer through the perfusion channel, the hydrogel absorbs water and expands and hardens, and the adjustable bending section remains in a bent state; S3, the operator performs surgery on the target area; S4. After the operation is completed, water is pumped out of the bending control layer through the perfusion channel, and the hydrogel is dehydrated and restored to its original state; S5. Operate the operating handle to release the bending wire, and the adjustable bending section is reset and straightened; S6. Remove the tube from the target area.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. By utilizing the water absorption and hardening characteristics of hydrogel, the medical catheter can be bent and the adjustable bending section can be kept in a bent state, which is convenient for the operator's intervention operation; 2. The hydrogel is reversible in absorbing and dehydrating water. Water is extracted from the hydrogel to reset the controllable bending segment and then it is removed from the target site to ensure safety during the removal process. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Schematic diagram of the structure of the tube body.

[0018] Figure 2 Schematic diagram of the cross-sectional structure of the adjustable bending section.

[0019] Figure 3 Schematic diagram of the cross-sectional structure of the adjustable bending section.

[0020] Figure 4 This is a schematic diagram of the structure of the pipe body and the bending wire.

[0021] The attached drawings are marked as follows: a, adjustable bending section; b. Main rigid section; 300. Pipe body; 400, bending control layer; 401, injection channel; 402, bending adjustment channel; 500, liner pipe; 600. Adjust the bend of the pull wire. DETAILED DESCRIPTION

[0022] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the specific implementation mode, structure, characteristics and effects of the present invention are described in detail below in combination with the accompanying drawings and preferred embodiments.

[0023] like Figure 1-4 As shown, the following embodiments disclose a controllable bending medical catheter and a bending adjustment method thereof.

[0024] Example 1 A controllable bending medical catheter comprises a tube body 300, wherein the tube body 300 is composed of a main rigid section b and an adjustable bending section a from the proximal end to the distal end; a bending control layer 400 is arranged in the adjustable bending section a, and the bending control layer 400 is filled with hydrogel; The tube body 300 is provided with a plurality of perfusion channels 401 from the main rigid section b and the adjustable bending section a; At least part of the adjustable bending section a has elastic deformation capability, and the bending shape of the adjustable bending section a is controlled by injecting liquid into the bending control layer 400 to adjust the hardness of the hydrogel; The tube body 300 is provided with a bending adjustment structure.

[0025] Specific reference Figure 1As shown, the tube body 300 is a conventional medical catheter and is hollow inside; the side of the tube body 300 close to the operator is the proximal end, and the side away from the operator is the distal end; when operating, the operator extends the distal end of the tube body 300 into the target part, operates at the distal end or outside the tube body 300 to bend the proximal end of the tube body 300, thereby performing corresponding operations; In this embodiment, the adjustable bending section a and the main rigid section b are coaxially connected and can be connected by welding, bonding or riveting to form a complete tube structure; Liquid water is injected into the bending control layer 400 through the perfusion channel 401, and the hydrogel of the bending control layer 400 absorbs water and hardens. At this time, combined with the bending adjustment structure, the adjustable bending section a is formed into a curved shape.

[0026] The bending control principle used in this embodiment is that the hydrogel will swell when water is injected, absorb water and swell, that is, the volume increases, but the overall structure remains intact and will not form a dissolved state; at the same time, the hydrogel after water injection can still maintain its elasticity; Hydrogel has the property of swelling upon absorbing water and can form a stable structure under certain conditions, which can maintain a balance between hardness and flexibility: the hydrogel can harden after absorbing water, and its water content can be controlled before bending to keep it soft and then filled and hardened to maintain the curved shape after completion.

[0027] In this embodiment, the characteristics of the hydrogel are fully utilized to maintain the shape while maintaining sufficient softness during the bending process to avoid damaging the blood vessel wall.

[0028] In addition, using hydrogels to control the bending of the tube has other advantages, such as being able to control its response time and controllability: the water absorption rate and hardening speed of the hydrogel may be slow, which is conducive to maintaining safety and precise control of the bending shape of the tube during operation; many hydrogel materials have good biocompatibility, and the three-dimensional network structure ensures that the hydrogel will not release harmful substances after absorbing water and swelling, and it is stable in the body environment for a long time and will not cause inflammation or other adverse reactions. The durability of the hydrogel in the process of repeated water absorption and drainage is relatively good, and it can restore its original shape without damaging the tube; the hydrogel material is easy to process and cut, and the effective distribution of the hydrogel and control of its expansion can be achieved, which can derive more bending shapes.

[0029] Using hydrogels to control bending can also achieve the reset of the adjustable bending segment a. The reason why the hydrogel water absorption and dehydration process is usually reversible is that the hydrogel is hydrophilic: the constituent units of the hydrogel, that is, the polymer chains, are highly hydrophilic, which means that they can attract and retain water molecules. When the hydrogel comes into contact with water, the water molecules are attracted by these hydrophilic groups and penetrate into the interior of the gel; The polymer chains are connected by cross-linking points to form a network structure. These cross-linking points restrict the free movement of the polymer chains, preventing them from dissolving in water, thereby maintaining the shape of the gel. The degree of cross-linking determines the tightness and water absorption capacity of the gel network; when the hydrogel begins to absorb water, water molecules fill the gaps in the network, causing the gel volume to expand (swell). As the amount of water absorbed increases, the interaction force between the water molecules and the polymer chains and the pressure inside the network gradually increase. Ultimately, when the driving force for water absorption reaches a balance with the network's constraint on water, the water absorption process stops, and the gel reaches a saturated state. When external conditions change, such as temperature, salt concentration, or mechanical force is applied, the attraction of water molecules inside the hydrogel is weakened or the network structure is changed, and the water molecules can be released back to the environment, the gel dehydrates and returns to its initial state. Since the cross-linked network structure remains intact during this process, the gel can absorb water again after losing water, realizing a reversible process of water absorption and dehydration.

[0030] In this embodiment, in order to prevent the liquid water injected into the perfusion channel 401 from overflowing, in this embodiment, the proximal end of the perfusion channel 401 is open and the distal end is closed.

[0031] That is, liquid water can only be injected into the bending control layer 400 , but cannot be output to the outside from the far end of the tube body 300 .

[0032] In order to ensure the elastic deformation capability of the adjustable bending section a, in this embodiment, the adjustable bending section a is made of a material with shape memory properties.

[0033] Nickel-titanium alloy is preferred.

[0034] Nickel-titanium alloy is a shape memory alloy, which is a special alloy that can automatically restore its plastic deformation to its original shape at a certain temperature. Its expansion rate is above 20%, and its fatigue life is 1*107. Its damping characteristics are 10 times higher than those of ordinary springs. Its corrosion resistance is better than the best medical stainless steel currently available. Therefore, it can meet the application requirements of various engineering and medical fields and is an excellent functional material.

[0035] In addition to its unique shape memory function, memory alloys also have excellent characteristics such as wear resistance, corrosion resistance, high damping and super elasticity.

[0036] Thus, when the operation is completed, water is pumped out of the bending control layer 400 to restore the hydrogel to its original state, and the bending structure is reset at the same time. At this time, the adjustable bending section a automatically returns to its original shape, and the operator then removes it from the target site.

[0037] In this embodiment, a bending adjustment channel 402 is provided in the tube body 300 , and the bending adjustment structure is disposed in the bending adjustment channel 402 .

[0038] Preferably, the bending adjustment structure is a bending adjustment wire 600 , and the distal end of the bending adjustment wire 600 is connected to the distal end of the tube body 300 .

[0039] Specific reference Figure 2 and Figure 3 As shown, in this embodiment, the bending channel 402 runs through the entire tube body 300, the end of the bending wire 600 is connected to the adjustable bending section a, and the farthest end of the adjustable bending section a is pulled, so that the entire adjustable bending section a is bent; The bending structure and method of the bending wire 600 for the adjustable bending section a are consistent with the bending structure in the prior art, and will not be elaborated here.

[0040] Preferably, in this embodiment, the adjustable bending section a is bent toward the side of the bending adjustment wire 600, as shown in FIG. Figure 4 shown.

[0041] Example 2 This embodiment is an improvement made on the basis of the embodiment 1, and its purpose is to provide a tube body 300 with good flexibility and shape retention ability; the specific implementation method is as follows: A hollow liner tube 500 is also provided in the tube body 300 , and the bending control layer 400 is located between the liner tube 500 and the inner wall of the tube body 300 .

[0042] Specific reference Figure 2 As shown, the center of the liner tube 500 is hollowed out as a through hole, and the bending control layer 400 is arranged between the liner tube 500 and the tube body 300. The liner tube 500 plays a certain supporting role on the tube body 300, so that the adjustable bend section a can provide necessary supporting force when bending and maintain the stability of the bend, while maintaining the flexibility and manipulability of the tube body 300.

[0043] Preferably, the tube body 300 is made of an advanced biocompatible material (such as Pebax) with good flexibility and strength; the outer layer of the tube body 300 may be coated with a special coating, such as PTFE, etc., to reduce friction and facilitate movement in the body, and may be hydrophilic to speed up the positioning of the catheter during operation.

[0044] In other embodiments, special structures such as springs may also be provided in the tube body 300 to provide support force for the adjustable curved section a.

[0045] Preferably, in this embodiment, the material of the inner lining tube 500 is a composite material.

[0046] For example, the combination of a PEEK outer layer and an inner wire braided layer ensures the flexibility of the tube body 300 while allowing it to maintain a certain shape after bending.

[0047] Example 3 This embodiment provides a method for adjusting the bending of a medical catheter, including the controllable bending medical catheter described in the above embodiment, wherein the bending adjustment structure is controlled by an operating handle, and includes the following steps: S1. Pull the operating handle, the operating handle pulls the bending adjustment wire 600, the distal end of the bending adjustment wire 600 pulls the distal end of the adjustable bending section a, and the adjustable bending section a bends; S2, injecting liquid water into the bending control layer 400 through the perfusion channel 401, the hydrogel absorbs water and expands and hardens, and the adjustable bending section a remains in a bent state; S3, the operator performs surgery on the target area; S4, after the operation is completed, water is pumped out of the bending control layer 400 through the perfusion channel 401, and the hydrogel is dehydrated and restored to its original state; S5, operate the operating handle to release the bending wire 600, and the adjustable bending section a is reset and straightened; S6. Withdraw the tube body 300 from the target site.

[0048] In this embodiment, the structures of the operating handle and the bending adjustment wire 600 and the operation method of pulling and releasing the wire are consistent with the bending adjustment structure in the prior art, and are not described in detail here.

[0049] In step S4, a needle or the like may be used to absorb water from the bending control layer 400.

[0050] In step S3, the target site is any location inside the target object that needs to be operated after expansion.

[0051] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technical personnel in this field can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A controllable bending medical catheter, comprising a tube body (300), wherein the tube body (300) is composed of a main rigid section b and an adjustable bending section a from the proximal end to the distal end; characterized in that: A bending control layer (400) is provided in the adjustable bending section a, and the bending control layer (400) is filled with hydrogel; The tube body (300) is provided with a plurality of perfusion channels (401) from the main rigid section b and the adjustable bending section a; At least part of the adjustable bending section a has elastic deformation capability, and the bending shape of the adjustable bending section a is controlled by injecting liquid into the bending control layer (400) to adjust the hardness of the hydrogel; A bending adjustment structure is provided in the tube body (300).

2. The controllable bending medical catheter according to claim 1, characterized in that: The perfusion channel (401) is open at the proximal end and closed at the distal end.

3. The controllable bending medical catheter according to claim 1, characterized in that: The adjustable bending section a is made of a material having shape memory properties.

4. The controllable bending medical catheter according to claim 1, characterized in that: A bending adjustment channel (402) is provided in the tube body (300), and the bending adjustment structure is arranged in the bending adjustment channel (402).

5. The controllable bending medical catheter according to claim 4, characterized in that: The bending adjustment structure is a bending adjustment pull wire (600), and the distal end of the bending adjustment pull wire (600) is connected to the distal end of the tube body (300).

6. The controllable bending medical catheter according to claim 1, characterized in that: A hollow inner liner tube (500) is also provided in the tube body (300), and the bending control layer (400) is located between the inner liner tube (500) and the inner wall of the tube body (300).

7. The controllable bending medical catheter according to claim 6, characterized in that: The material of the inner liner pipe (500) is a composite material.

8. A method for adjusting the bending of a medical catheter, comprising the controllable bending medical catheter according to claim 5, wherein the bending adjustment structure is controlled by an operating handle, comprising the following steps: S1. Pull the operating handle, the operating handle pulls the bending adjustment wire (600), the distal end of the bending adjustment wire (600) pulls the distal end of the adjustable bending section a, and the adjustable bending section a bends; S2, injecting liquid water into the bending control layer (400) through the perfusion channel (401), the hydrogel absorbs water, expands and hardens, and the adjustable bending section a remains in a bent state; S3, the operator operates the target part; S4, after the operation is completed, water is pumped out of the bending control layer (400) through the perfusion channel (401), and the hydrogel is dehydrated and restored to its original state; S5, operate the operating handle to release the bending adjustment wire (600), so that the adjustable bending section a is reset and straightened; S6. Withdraw the tube body (300) from the target site.

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