A support catheter with controllable distal flexibility

Abstract

The present invention provides a support catheter with controllable distal flexibility, which belongs to the technical field of medical devices; it comprises a support tube body, wherein the support tube body has a protective layer, a support layer and an inner lining layer arranged in sequence from the outside to the inside; the distal end of the support tube body has a controllable flexibility section, and the controllable flexibility section is used to extend from the distal end of the outer sheath tube to the thrombus position; the support layer of the controllable flexibility section includes a plurality of movable joints connected in sequence to increase the flexibility of the controllable flexibility section; a retractable filling piece is provided inside at least one end of the movable joint, and the filling piece can be extended from both ends of the movable joint to fill the gap between two adjacent movable joints to increase the support of the controllable flexibility section; this support catheter can accurately adjust the flexibility and support according to different stages of the operation, optimize the structural design, improve the safety of the operation and the convenience of operation, and has extremely high application value.

Description

Technical Field

[0001] The present invention belongs to the technical field of medical devices, and in particular relates to a support catheter with controllable distal flexibility. Background Art

[0002] For patients with acute ischemic stroke, if the onset time is within a certain time window (currently usually 6-24 hours, the specific time window will be determined based on the patient's individual condition and imaging assessment) and meets specific imaging criteria (such as the presence of large vessel occlusion, a small infarct core, etc.), and traditional drug thrombolytic therapy is ineffective or unsuitable, mechanical thrombectomy is an important treatment option.

[0003] Mechanical thrombectomy refers to the use of interventional technology to deliver a special thrombectomy device through the blood vessels to the location of the thrombus, directly grasping or aspirating the thrombus, thereby reopening the blocked blood vessels and restoring blood supply to the brain.

[0004] Patent document number CN104068909A discloses an intracranial vascular thrombus remover and thrombus removal device. When removing a thrombus, the thrombus remover is first introduced into the blood vessel, a guide wire is used to pass through the lesion site, the inner tube is passed through the lesion site along the guide wire, and the thrombus remover is released through the inner tube to perform the thrombus removal operation. After the thrombus removal is completed, the thrombus remover is withdrawn into the inner tube, the inner tube is retracted into the outer sheath tube and withdrawn from the body together with the outer sheath tube.

[0005] The above-mentioned technical solution is generally applicable to the slightly thicker sections of the brain blood vessels. If the thrombus is located in a thinner position of the blood vessel, the outer sheath cannot directly reach the lesion location due to its large diameter. At this time, a support catheter is generally required. The support catheter is nested in the outer sheath. During the operation, the outer sheath is first transported to a position close to the thrombus. Then, the support catheter is extended from the distal end of the outer sheath and continues to advance toward the thrombus location until it reaches the thrombus location. Then, the inner tube carries the thrombus remover and reaches the thrombus location along the support catheter to perform the thrombus removal operation.

[0006] During the aforementioned procedure, as the support catheter extends from the distal end of the outer sheath and advances toward the location of the thrombus, the overall flexibility of the support catheter is required to facilitate navigation through the tortuous blood vessels without damaging them. However, once the support catheter is in place, the thrombus remover must be pushed toward the thrombus location through the support catheter to maintain support, preventing displacement and ensuring accurate placement of the thrombus remover. However, the flexibility of existing support catheters cannot be adjusted appropriately to meet the needs of different stages.

[0007] Therefore, it is necessary to provide an improved technical solution to the above-mentioned deficiencies in the prior art. Summary of the Invention

[0008] The purpose of the present invention is to provide a support catheter with controllable distal flexibility, so as to solve the technical problem that the existing support catheter cannot adjust the flexibility according to the requirements of different stages.

[0009] In order to achieve the above objectives, the support catheter with controllable distal flexibility of the present invention provides the following technical solutions:

[0010] A support catheter with controllable distal flexibility includes a support tube body, which has a protective layer, a support layer and an inner lining layer arranged in sequence from the outside to the inside. The distal end of the support tube body has a controllable flexibility section, which is used to extend from the distal end of the outer sheath to the location of the thrombus. The support layer of the controllable flexibility section includes multiple movable joints connected in sequence to increase the flexibility of the controllable flexibility section. A retractable filling piece is provided inside at least one end of the movable joint. The filling piece can be extended from both ends of the movable joint to fill the gap between two adjacent movable joints to increase the support of the controllable flexibility section.

[0011] As a further optimized technical solution, a receiving cavity for placing a filling piece is provided on the side wall of the movable joint, and a movable channel facing the adjacent movable joint is opened on the receiving cavity, and the filling piece is used to enter and exit the receiving cavity from the movable channel.

[0012] As a further optimized technical solution, the filling piece is an airbag, and a conveying component for filling the interior of the airbag with fluid is arranged on the protective layer or the inner lining layer.

[0013] As a further optimized technical solution, the conveying component is a filling channel provided on the protective layer or the lining layer, and the filling channel is used to connect with the accommodating cavity on each of the movable joints in the flexibility controllable section.

[0014] As a further optimized technical solution, arc-shaped notches are respectively provided at both ends of the movable joint to increase the gap between the two movable joints.

[0015] As a further optimized technical solution, the movable channel is arranged in the middle of the arc-shaped notch.

[0016] As a further optimized technical solution, any two adjacent movable joints are connected via a connecting component.

[0017] As a further optimized technical solution, the connecting component includes a connecting ear and a limiting groove. The connecting ear is arranged at one end of the movable joint, and the limiting groove is arranged at the other end of the movable joint. The connecting ear on one movable joint is used to cooperate with the limiting groove on the adjacent movable joint to realize the connection of the movable joint. The limiting groove and the connecting ear are both circular.

[0018] As a further optimized technical solution, the volume of the limiting groove is larger than the volume of the connecting ear to increase the flexibility of the movable joint connection.

[0019] As a further optimized technical solution, the connecting components are arranged in two groups symmetrically along the radial direction.

[0020] Beneficial effects:

[0021] (1) By setting a flexible controllable section at the distal end of the support tube body, and the support layer of this section adopts a plurality of sequentially connected movable joint structures, combined with a retractable filling piece, the support catheter can flexibly adjust its own flexibility and support at different stages according to the actual surgical needs; in the process of advancing from the distal end of the outer sheath to the thrombus location, the filling piece retracts, and the gap between the movable joints is larger. The support catheter shows good flexibility and can easily pass through the tortuous and complex blood vessels, effectively reducing friction and damage to the inner wall of the blood vessels, and reducing the risk of complications such as blood vessel rupture and spasm during the operation. When the support catheter reaches the thrombus location and needs to push the thrombus remover, the filling piece extends to fill the gap between the movable joints, significantly enhancing the support performance of the support catheter, ensuring that the support catheter can remain stable and not easily displaced during the process of pushing the thrombus remover, so that the thrombus remover can accurately reach the thrombus location, greatly improving the success rate of the thrombus removal operation.

[0022] (2) The design of the accommodating cavity and movable channel on the side wall of the movable joint provides a reasonable space and path for the placement and extension of the filling piece, ensuring that the filling piece can move in and out smoothly, thereby achieving effective adjustment of the performance of the supporting catheter; at the same time, the arc-shaped notches at both ends of the movable joint not only increase the gap between the movable joints, further improving the flexibility of the flexible controllable section, but also set the movable channel in the middle, optimizing the extension and retraction path of the filling piece, making the entire structure more compact and reasonable, and the operation more convenient and efficient.

[0023] (3) Adjacent movable joints are connected by connecting parts consisting of connecting ears and limiting grooves. This design not only ensures the stability of the connection between the movable joints, but also gives the movable joints relatively flexible movement capabilities by setting the volume of the limiting groove larger than the volume of the connecting ears, thereby ensuring the performance requirements of the supporting catheter in different states as a whole; moreover, the two groups of connecting parts arranged symmetrically along the radial direction further enhance the stability of the connection, so that the supporting catheter can withstand various forces in a complex vascular environment and maintain the integrity and functionality of the structure.

[0024] (4) When the filling member adopts an airbag design, the delivery components arranged on the protective layer or the inner lining layer, such as the filling channel, can conveniently fill or release fluid into the airbag, thereby achieving precise control of the airbag state. This collaborative design is not only simple to operate, but also can quickly and effectively change the flexibility and support of the support catheter, meeting the need for rapid adjustment of the support catheter performance during surgery. At the same time, the filling channel connects the accommodating cavity on each movable joint, ensuring that each airbag can be inflated and deflated synchronously, so that the performance of the support catheter at different parts remains consistent, improving the reliability and stability of the surgical operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The drawings and the accompanying drawings, which constitute part of this application, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an undue limitation of the present invention. Among them:

[0026] Figure 1 is a schematic cross-sectional view of a compliance controllable section according to an embodiment of the present invention;

[0027] Figure 2 This is a schematic diagram of the support layer structure of the controllable compliance section according to one embodiment of the present invention;

[0028] Figure 3 Schematic diagram of the movable joint structure of an embodiment of the present invention.

[0029] In the figure: 1. Flexibility controllable section; 101. Protective layer; 102. Support layer; 1021. Active joint; 1022. Accommodating cavity; 1023. Active channel; 1024. Arc-shaped notch; 103. Lining layer; 2. Filling piece; 3. Conveying component; 4. Connecting ear; 5. Limiting groove. DETAILED DESCRIPTION

[0030] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field are within the scope of protection of the present invention.

[0031] In the description of the present invention, the terms "longitudinal", "transverse", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and do not require that the present invention must be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention. The terms "connected" and "connected" used in the present invention should be understood in a broad sense. For example, they can be fixedly connected or detachably connected; they can be directly connected or indirectly connected through an intermediate component. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to the specific circumstances. In addition, the term "proximal end" refers to the end close to the operator, and "distal end" refers to the end away from the operator.

[0032] The shapes and sizes of the components in the drawings do not reflect the actual proportions of the products, and are only intended to illustrate the contents of the present invention.

[0033] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments. It should be noted that, in the absence of conflict, the embodiments and features of the embodiments of the present invention can be combined with each other.

[0034] The present invention provides a support catheter with controllable distal flexibility. The support catheter is mainly composed of a support tube body. The support tube body is sequentially provided with a protective layer, a support layer and an inner lining layer from the outside to the inside. A flexibility controllable section is specially provided at the distal end of the support tube body. The support layer of this section is composed of a plurality of movable joints connected in sequence, and retractable filling pieces are provided at both ends of the movable joints. When the support catheter needs to have higher flexibility, the filling piece shrinks inside the movable joint. At this time, the overall flexibility of the flexibility controllable section is higher, thereby facilitating reaching the thrombus location. When the thrombus remover needs to be delivered, the filling piece extends from both ends of the movable joint to fill the movable gap between the movable joints, thereby reducing the flexibility of the flexibility controllable section and increasing the support.

[0035] Example 1

[0036] like Figure 1-3 For details, please refer to Figure 1. The support catheter with controllable distal flexibility includes a support tube body, which has a protective layer 101, a support layer 102 and an inner lining layer 103 arranged in sequence from the outside to the inside. Among them, the protective layer 101 is made of polyetheretherketone (PEEK) material with biocompatibility and excellent wear resistance. This material can not only provide reliable external protection for the support catheter when it moves in the complex environment within the blood vessel, effectively resisting possible physical damage, but also rely on its smooth surface properties to greatly reduce the friction coefficient between the support catheter and the blood vessel wall, reduce irritation and potential damage to the blood vessel wall, and reduce the risk of vascular inflammation or other complications during surgery. The support layer 102 can be made of shape memory alloy - Nitinol. Nitinol alloy has a unique shape memory effect and superelastic properties, which enables the support layer 102 to provide stable and reliable support for the support catheter while also adapting to the natural curvature and physiological movement of the blood vessel to a certain extent, ensuring that the support catheter can always maintain a stable shape and position in the blood vessel, providing a solid support foundation for subsequent thrombectomy operations. The inner lining layer 103 can be made of medical-grade silicone rubber material, which has an extremely low surface friction coefficient and good biocompatibility, and can provide an ideal internal environment for the smooth advancement and withdrawal of the inner tube or thrombus remover within the support catheter.

[0037] The controllable compliance section 1 is located at the distal end of the support tube body. The controllable compliance section 1 is used to extend from the distal end of the outer sheath to the location of the thrombus. It is a key part for achieving flexible conversion between the flexibility and support of the support catheter.

[0038] like Figure 2 、 Figure 3 As shown, the support layer 102 of the flexible controllable segment 1 is composed of a plurality of movable joints 1021 connected in sequence, and these movable joints 1021 are connected stably and flexibly by connecting components. Specifically, the connecting components include a connecting ear 4 and a limiting groove 5. The connecting ear 4 is integrally formed at one end of the movable joint 1021, and is in the form of a circular sheet and protrudes; the limiting groove 5 is processed at the other end of the movable joint 1021 and is a circular groove adapted to the connecting ear 4. The connecting ear 4 on one movable joint 1021 is tightly embedded in the limiting groove 5 on the adjacent movable joint 1021, achieving a reliable connection between the movable joints 1021. This facilitates the relative rotation between the movable joints 1021, and further facilitates the flexible swinging of the entire flexible controllable segment 1 within the blood vessel.

[0039] Furthermore, the inner diameter of the limiting groove 5 is slightly larger than the outer diameter of the connecting ear 4, that is, the volume of the limiting groove 5 is greater than the volume of the connecting ear 4. The pair of mutually cooperating limiting grooves 5 and the connecting ear 4 form a certain movable gap, ensuring that the movable joint 1021 can rotate and bend relatively flexibly within a certain range to adapt to the complex geometric shape of the blood vessel. At the same time, two sets of such connecting components are arranged radially symmetrically along the movable joint 1021. This symmetrical layout further enhances the stability and reliability of the connection, effectively preventing loose connection or structural deformation caused by uneven force in complex vascular environments, thereby increasing the compliance of the controllable compliance section 1.

[0040] Retractable filling pieces 2 are provided inside both ends of the movable joint 1021 . The filling pieces 2 can extend from both ends of the movable joint 1021 to fill the gap between two adjacent movable joints 1021 , so as to increase the support of the flexible controllable section 1 .

[0041] Specifically, a cavity 1022 for accommodating the filler 2 is provided on the side wall of the movable joint 1021. A movable passage 1023 is defined in the cavity 1022, which faces the adjacent movable joint 1021. The filler 2 is adapted to enter and exit the cavity 1022 through the movable passage 1023. The diameter of the movable passage 1023 is moderate, ensuring smooth passage of the filler 2 while also providing necessary restraint when the filler 2 is extended or retracted, preventing excessive movement or displacement.

[0042] In this embodiment, filler 2 utilizes a high-performance medical-grade airbag, partially fixed within cavity 1022. This airbag exhibits excellent elasticity, flexibility, and biocompatibility, enabling stable operation under varying pressures. Specifically, when filling the gap between the two movable joints 1021, the airbag deforms through volume change, extending along movable channel 1023 out of cavity 1022 to complete the filling process.

[0043] The protective layer 101 is provided with a delivery component 3 for filling the airbag interior with fluid. In this embodiment, the delivery component 3 is a filling channel provided on the protective layer 101. Specifically, the filling channel is a groove provided on the protective layer 101. The filling channel connects the receiving cavity 1022 of each movable joint 1021 in the controllable compliance section 1. A conventional high-precision fluid control device is installed at the proximal end of the filling channel, which precisely controls the injection and discharge of fluid, enabling precise regulation of the airbag state.

[0044] Specifically, during the process of advancing the support catheter from the distal end of the outer sheath toward the location of the thrombus, the fluid in the airbag is discharged through the fluid control device, causing the filler 2 to retract into the accommodating chamber 1022. At this time, the gaps between the movable joints 1021 are relatively large, and the flexible controllable section 1 exhibits excellent flexibility, easily bending and moving along the tortuous path of the blood vessel, reducing pressure and damage to the blood vessel wall. When the support catheter reaches the location of the thrombus and the thrombus remover needs to be pushed, an appropriate amount of fluid is injected into the airbag through the fluid control device, causing the airbag to rapidly expand and extend from the movable channel 1023, tightly filling the gaps between adjacent movable joints 1021. This significantly enhances the support of the flexible controllable section 1, providing stable and reliable support for the push of the thrombus remover, ensuring that the thrombus remover can accurately reach the thrombus location.

[0045] Furthermore, in order to optimize the degree of flexibility adjustment of the flexibility controllable section 1, arc-shaped notches 1024 are provided at both ends of the movable joint 1021, which can increase the gap between the two movable joints 1021. This allows the flexibility controllable section 1 to have greater freedom when bending. When the support catheter passes through a tortuous blood vessel, the arc-shaped notch 1024 can effectively reduce the mutual interference between the movable joints 1021, allowing the support catheter to more naturally conform to the curved shape of the blood vessel, further improving its flexibility and adaptability in the blood vessel, and reducing the risk of damage to the blood vessel wall. In addition, the active channel 1023 is cleverly arranged in the middle of the arc-shaped notch 1024. This layout optimizes the extension and retraction path of the filling piece 2. When the filling piece 2 is extended, it can smoothly fill the gap between the movable joints 1021 along the central axis direction of the arc-shaped notch 1024, ensuring uniform and stable filling; when the filling piece 2 is retracted, it can also smoothly return to the accommodating cavity 1022 along the original path, avoiding the performance of the supporting catheter being affected by the offset or jamming of the filling piece 2. The movable channel 1023 is set in the middle of the arc-shaped notch 1024.

[0046] Example 2

[0047] This embodiment provides another support catheter with controllable distal flexibility. Almost all structures in this embodiment are the same as those in Example 1. The only difference is the number of filling pieces provided.

[0048] Specifically, a retractable filling piece is provided inside one end of the movable joint in this embodiment, and the filling pieces on all movable joints are provided at the same end. For example, the filling pieces on all movable joints are provided at the distal end. Then, when it is necessary to adjust the support of the flexibility controllable section, the filling piece at the distal end of each movable joint is used to fill the gap between the proximal end of the adjacent movable joint.

[0049] Example 3

[0050] This embodiment provides another support catheter with controllable distal flexibility. Almost all structures in this embodiment are the same as those in Example 1. The only difference is the location of the filling channel. In this embodiment, the filling channel can also be set on the inner lining layer.

[0051] Example 4

[0052] This embodiment also provides a support catheter with controllable distal flexibility. Almost all structures in this embodiment are the same as those in Example 1. The only difference lies in the specific structure of the filling channel. In this embodiment, the filling channel is a tube body fixedly arranged on the protective layer or the lining layer.

[0053] In summary, the support catheter with controllable distal flexibility provided by the present invention, through the precise design and coordinated work of the above parts, shows excellent performance in mechanical thrombectomy surgery. It can flexibly and accurately adjust its own flexibility and support according to the actual needs of the surgery, providing a strong guarantee for the successful implementation of the surgery and significantly improving the treatment effect and prognosis quality of the patient.

[0054] It will be understood that the above description is merely exemplary and the embodiments of the present application do not limit this.

[0055] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are within the scope of protection of the pending claims of the present invention.

Claims

1. A support catheter with controllable distal flexibility, comprising a support tube body, wherein the support tube body has a protective layer (101), a support layer (102) and an inner lining layer (103) arranged in sequence from the outside to the inside, characterized in that: The distal end of the support tube body has a controllable compliance section (1), which is used to extend from the distal end of the outer sheath to the location of the thrombus. The support layer (102) of the controllable compliance section (1) includes a plurality of sequentially connected movable joints (1021) to increase the flexibility of the controllable compliance section (1). A retractable filling member (2) is provided inside at least one end of the movable joint (1021). The filling member (2) can extend from at least one end of the movable joint (1021) to fill the gap between two adjacent movable joints (1021), thereby increasing the support of the controllable compliance section (1). The filling member (2) is an airbag, and a conveying component (3) for filling the interior of the airbag with fluid is arranged on the protective layer (101) or the inner lining layer (103).

2. The support catheter with controllable distal flexibility according to claim 1, characterized in that: A receiving cavity (1022) for accommodating a filling piece (2) is provided on the side wall of the movable joint (1021), a movable channel (1023) facing the adjacent movable joint (1021) is provided on the receiving cavity (1022), and the filling piece (2) is used to enter and exit the receiving cavity (1022) through the movable channel (1023).

3. The support catheter with controllable distal flexibility according to claim 1, characterized in that: The conveying component (3) is a filling channel provided on the protective layer (101) or the inner lining layer (103), and the filling channel is used to communicate with the accommodating cavity (1022) on each movable joint (1021) in the controllable compliance section (1).

4. The support catheter with controllable distal flexibility according to claim 2, characterized in that: Arc-shaped notches (1024) are respectively provided at both ends of the movable joint (1021) for increasing the gap between the two movable joints (1021).

5. The support catheter with controllable distal flexibility according to claim 4, characterized in that: The movable channel (1023) is arranged in the middle of the arc-shaped notch (1024).

6. The support catheter with controllable distal flexibility according to claim 1, characterized in that: Any two adjacent movable joints (1021) are connected via a connecting component.

7. The support catheter with controllable distal flexibility according to claim 6, characterized in that: The connecting component comprises a connecting ear (4) and a limiting groove (5), wherein the connecting ear (4) is arranged at one end of the movable joint (1021), and the limiting groove (5) is arranged at the other end of the movable joint (1021), and the connecting ear (4) on one movable joint (1021) is used to cooperate with the limiting groove (5) on the adjacent movable joint (1021) to achieve the connection of the movable joint (1021), and the limiting groove (5) and the connecting ear (4) are both circular.

8. The support catheter with controllable distal flexibility according to claim 7, characterized in that: The volume of the limiting groove (5) is greater than the volume of the connecting ear (4), so as to increase the flexibility of the connection of the movable joint (1021).

9. The support catheter with controllable distal flexibility according to claim 6, characterized in that: The connecting components are symmetrically arranged in two groups along the radial direction.

Images