Multi-segment controllably curved catheter with asymmetric curved shape

Abstract

The application discloses a multi-section controllable bending catheter with asymmetric bending shape, realizes multi-section controllable bending of a microcatheter for minimally invasive or interventional treatment by arranging multiple bending sections with significantly enhanced flexibility on the distal end of the high-performance catheter, effectively increases the controllable bending angle range, can also adjust the bending sections to make the size range of the traction force of each bending section to bend and fully bend, realizes the control of the bending sequence of each bending section, and uses the hypotube with inconsistent axial total length of all the hollow patterns on the two sides as the metal reinforcing layer of the bending section to obtain asymmetric bending sections, so that the controllable bending catheter has inconsistent maximum bending angles in bidirectional bending at the asymmetric bending sections, forms the desired asymmetric bending shape, the overall structure is precise, transmission is smooth, the bending shape can be accurately manufactured, the bending adjustment mode is also various, and the controllable bending catheter can adapt to more complex and circuitous human body lumen interventional or minimally invasive treatment use requirements, and the application range of the controllable bending catheter is expanded.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of medical devices, in particular to a multi-segment controllable bending catheter with asymmetric bending shape. BACKGROUND

[0002] Catheters are indispensable auxiliary tools in human body septum puncture, cardiovascular intervention, peripheral vascular intervention, heart atrial septostomy, renal artery ablation, heart valve repair, tumor interventional embolization and other procedures that require precise positioning of branched blood vessels or minimally invasive treatment of human body lumen. A pre-plasticity catheter is usually used to pre-establish a channel from the outside to the target position, providing a channel for subsequent diagnostic and therapeutic devices to enter. However, due to individual differences in human body structure, pre-plasticity catheters cannot fully meet all clinical needs. Once the inserted catheter does not meet the physiological structure of the patient, it needs to be removed and a new catheter needs to be inserted, increasing the operation time and possibly causing harm to the patient.

[0003] To adapt to the individual differences in human body anatomy, controllable bending catheters have emerged and are widely used. A controllable bending catheter is a catheter with a controllable bending segment at the distal end of the catheter body. By controlling the handle of the catheter, the pulling wire connected to the controllable bending segment is moved axially, causing the distal end of the catheter body to bend at different angles. When the bending angle of the controllable bending segment meets the specific physiological structure of the human body lumen, the handle is stopped, and the distal end of the catheter body is then aligned with the target lumen entrance. Diagnostic and / or therapeutic devices are then delivered through the catheter body into the target lumen.

[0004] Controllable bending catheters in the prior art usually have only one bending segment at the distal end. The distal part of the single bending segment can bend in one, two, three or four directions, with consistent maximum bending angles in each direction. The maximum bending angle of a single bending segment is limited. If there are multiple bending segments, the controllable bending angle range can be effectively increased. Some complex and winding human body lumens require the distal end of the catheter to change the bending direction and shape in real time, or even have multiple bending shapes. Therefore, a controllable bending catheter with multiple bending segments is considered to solve the above technical problems and obtain inconsistent maximum bending angles in each bending direction at the bending segments, thereby adapting to more complex and winding human body lumen interventions or minimally invasive treatments. SUMMARY

[0005] To overcome the shortcomings of the prior art, the present application provides a multi-segment controllable bending catheter with asymmetric bending shape, which can adapt to more complex and winding human body lumen interventions or minimally invasive treatments, expanding the application range of controllable bending catheters.

[0006] In order to achieve the above-mentioned purpose, the technical scheme adopted by the present application to solve its technical problems is: a multi-section controllable bending catheter with asymmetric bending shape, comprising a high-performance catheter and a control handle, the distal end of the high-performance catheter has a certain flexibility, the proximal end is connected and fixed to the control handle, the wall thickness is sequentially divided into a polymer inner layer, a metal reinforcing layer and a polymer outer layer from inside to outside, a pair of wire drawing cavities are arranged between the polymer inner layer and the metal reinforcing layer, the pair of wire drawing cavities are symmetrically arranged and both penetrate the high-performance catheter in the axial direction, a traction wire is arranged in the cavity, a winding and unwinding mechanism is arranged in the control handle, one end of the traction wire is fixed to the distal end of the wire drawing cavity, the other end is connected to the winding and unwinding mechanism, at least two bending sections with significantly enhanced flexibility are arranged on the distal end of the high-performance catheter, at least one of the bending sections is an asymmetric bending section, the metal reinforcing layer thereon is a hypotube, the surface of the hypotube is cut and processed to form regularly distributed hollow patterns, and all the hollow patterns on the two sides of the pair of wire drawing cavities have inconsistent total lengths in the axial direction.

[0007] As a preferred, the metal reinforcing layer on the distal end of the high-performance catheter is composed of an integral metal tube.

[0008] As a preferred, all the hollow patterns on the same side of the wire drawing cavity on the hypotube are consistent in shape and size and are arranged at equal intervals in the axial direction of the tube body.

[0009] As a preferred, the hollow patterns are closed patterns.

[0010] As a preferred, the hollow patterns are circumferentially surrounded by an angle not less than 120 degrees.

[0011] As a preferred, the wire drawing cavity is located at the circumferential midpoint of the hollow pattern.

[0012] As a preferred, the hollow patterns are spiral open patterns.

[0013] As a preferred, the winding and unwinding mechanism includes but is not limited to a screw rod, a wire wheel and a sliding block.

[0014] As a preferred, a hand adjustment device is arranged on the control handle, the hand adjustment device is connected and drives the winding and unwinding mechanism, and the hand adjustment device includes but is not limited to a rotating wheel and a push button.

[0015] Due to the use of the above technical scheme, the present application has the following beneficial effects compared with the prior art:

[0016] The multi-segment controlled bending of the microcatheter for minimally invasive or interventional treatment is realized by setting multiple bending segments with significantly enhanced flexibility on the distal end of the high-performance catheter, the controllable bending angle range is effectively increased, the size range of the traction force of each bending segment to make each bending segment bend and fully bend is adjusted, the control of the bending sequence of each bending segment is realized, and the asymmetric bending segment is obtained by applying the hypotube with inconsistent axial total length of all the hollow patterns as the metal reinforcing layer of the bending segment, so that the controllable bending catheter has inconsistent maximum bending angles in bidirectional bending at the asymmetric bending segment, the desired asymmetric bending shape is formed, the overall structure is precise, the transmission is smooth, the bending shape can be accurately manufactured, the bending adjustment mode is also various, and the use requirements of more complex and circuitous human body lumen intervention or minimally invasive treatment can be met, and the application range of the controllable bending catheter is expanded. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 is a structural schematic diagram of an embodiment of the multi-segment controllable bending catheter with an asymmetric bending shape.

[0018] Figure 2 is a structural schematic diagram of the high-performance catheter in an embodiment of the multi-segment controllable bending catheter with an asymmetric bending shape.

[0019] Figure 3 is a structural schematic diagram of the metal reinforcing layer of the high-performance catheter at the distal end of the high-performance catheter in an embodiment of the multi-segment controllable bending catheter with an asymmetric bending shape.

[0020] Figure 4 is a structural schematic diagram of bidirectional bending of the hypotube at the asymmetric bending segment in an embodiment of the multi-segment controllable bending catheter with an asymmetric bending shape.

[0021] Figure 5 is a structural schematic diagram of the high-performance catheter at a pair of asymmetric bending segments at the distal end of the high-performance catheter in an embodiment of the multi-segment controllable bending catheter with an asymmetric bending shape.

[0022] Figure 6 is a structural schematic diagram of the hypotube at the asymmetric bending segment in other various embodiments of the multi-segment controllable bending catheter with an asymmetric bending shape.

[0023] Figure 7 is a schematic diagram of the controlled bending structure in an embodiment and other various embodiments of the multi-segment controllable bending catheter with an asymmetric bending shape.

[0024] In the figure: 1, high-performance catheter; 2, control handle; 3, polymer inner layer; 4, metal reinforcing layer; 5, polymer outer layer; 6, wire drawing cavity; 7, traction wire; 8, winding and unwinding mechanism; 9, curved section; 10, hypotube; 11, hollow pattern; 12, manual adjustment device; 13, positioning ring. DETAILED DESCRIPTION

[0025] The content of the present application will be further described in detail below in combination with specific embodiments:

[0026] Figures 1 to 3 An embodiment of a multi-section controllable curved catheter with asymmetric curved shape is disclosed, comprising a high-performance catheter 1 and a control handle 2, the distal end of the high-performance catheter 1 has a certain flexibility, the proximal end is connected to the fixed control handle 2, the wall thickness is sequentially divided into a polymer inner layer 3, a metal reinforcing layer 4 and a polymer outer layer 5 from inside to outside, a pair of wire drawing cavities 6 is provided between the polymer inner layer 3 and the metal reinforcing layer 4, the pair of wire drawing cavities 6 are symmetrically arranged and both penetrate the high-performance catheter 1 along the axial direction, a traction wire 7 is arranged in the cavity, a winding and unwinding mechanism 8 is arranged in the control handle 2, one end of the traction wire 7 is fixed to the distal end of the wire drawing cavity 6, the other end is connected to the winding and unwinding mechanism 8, two curved sections 9 with significantly enhanced flexibility are arranged on the distal end of the high-performance catheter 1, both curved sections 9 are asymmetric curved sections 9, the metal reinforcing layer 4 is an entire hypotube 10, the surface is cut to form regularly distributed hollow patterns 11, all hollow patterns 11 on both sides of the pair of wire drawing cavities 6 at the asymmetric curved section 9 have inconsistent axial total length.

[0027] In the above embodiment and other embodiments of the present application:

[0028] The metal reinforcing layer 4 is preferably composed of an entire metal pipe material, the metal pipe material is usually made of stainless steel or nickel-titanium alloy or cobalt-chromium alloy, part of the area on the metal pipe material is cut to form a conventional hypotube 10 with regularly uniform hollow patterns 11 to form a symmetric curved section 9, part of the area is cut to form a hypotube 10 with all hollow patterns 11 on both sides having inconsistent axial total length to form an asymmetric curved section 9, other areas are cut to form a spiral tube, a woven tube or a hypotube with significantly weaker flexibility than the symmetric curved section 9 and the asymmetric curved section 9, taking the above embodiment as an example, combining with Figure 4 and Figure 5, the high-performance catheter 1 distal end from the self-bending section 9 to the side where the traction wire 7 is located bends to the inside of the hollow pattern 11, and stops bending after the tube wall is fully flattened and abuts against each other, which can limit a maximum bending angle, and realize accurate control of the maximum bending angle at each bending section 9. The difference lies only in that the bidirectional maximum bending angles of the symmetrical bending sections 9 are consistent, and the bidirectional maximum bending angles of the hypotube 10 at the asymmetrical bending sections 9 are inconsistent. 5A illustrates that the high-performance catheter 1 distal end is bent individually in two directions at a pair of asymmetrical bending sections 9, and 5B illustrates that the high-performance catheter 1 distal end is bent simultaneously in two directions at a pair of asymmetrical bending sections 9. In the design and production process of the multi-segment controllable bending catheter, the flexibility of each bending section 9 can be differentiated, the range of traction force for causing bending and full bending of each bending section 9 is adjusted, the control of the bending sequence of each bending section 9 is realized, and the number, distribution and bidirectional maximum bending angle of the symmetrical bending sections 9 and the asymmetrical bending sections 9 are not limited, which should be adjusted according to the actual operation requirements;

[0029] In combination with Figure 4 and Figure 6 , in the above embodiments, 6A, 6B and 6C, the shapes and sizes of all hollow patterns 11 on the same wire drawing cavity 6 side of the hypotube 10 at the asymmetrical bending section 9 are consistent and arranged at equal intervals along the tube body axis, in the above embodiments and 6A, all hollow patterns 11 on both sides of the hypotube 10 at the asymmetrical bending section 9 are symmetric about the central axis of the hypotube 10, in 6B and 6C, all hollow patterns 11 on both sides of the hypotube 10 at the asymmetrical bending section 9 are staggered along the central axis of the hypotube 10, in the above embodiments, 6A, 6B and 6C, the hollow patterns 11 on the hypotube 10 at the asymmetrical bending section 9 are all closed patterns, which are annular rectangles, and the width of the annular rectangle on one side is greater than that on the other side. The circumferential angle of such hollow pattern 11 is preferably not less than 120 degrees, and the wire drawing cavity 6 is located at the circumferential midpoint of the hollow pattern 11, which ensures that the hollow pattern 11 can be uniformly stressed and resist the stress of the tube body when the hypotube 10 is bent, and the hollow pattern 11 can be fully flattened, but the tube body does not deform plastically. In 6D, the hypotube 10 at the asymmetrical bending section 9 is in the shape of a spiral strip, and the hollow pattern 11 is an open spiral pattern, which is a continuous spiral gap, and the width of the gap on one side is greater than that on the other side after cutting processing. In 6E, the hollow pattern 11 at the asymmetrical bending section 9 has a regular change in circumferential angle, but the hollow pattern 11 on both sides of a pair of traction wires is still wide and narrow;

[0030] As Figure 7As shown in Figures 7A, 7B, and 7C, the distal end of the high-performance catheter 1 gradually narrows to form a constricted opening that facilitates passage through the human body lumen. The distal end of the drawing chamber 6, which runs axially through the high-performance catheter 1, terminates inside the opening. A positioning ring 13 is fixed within the wall thickness of the distal end of the high-performance catheter 1. The distal end of the traction wire 7 is connected to and fixed by the positioning ring 13, thus achieving connection, fixation, and traction transmission of the distal end of the high-performance catheter 1. In Figure 7A, the winding and unwinding mechanism 8 and the manual adjustment device 12 on the control handle 2 are represented as a reel and a rotating wheel. The reel and the rotating wheel are coaxially arranged perpendicular to the axis of the high-performance catheter 1 and are connected and fixed or integrated. The proximal ends of a pair of traction wires 7 are respectively connected to the two sides of the fixed reel. Rotating the rotating wheel causes the reel to rotate, causing one traction wire 7 to wind up while the other traction wire 7 loosens, resulting in a difference in length between the two traction wires 7 remaining in the drawing chamber 6. Therefore, the distal end of the high-performance catheter 1, with a certain degree of flexibility, can move towards the side of the drawing chamber 6 where the shorter traction wire 7 is located. The slight bend and significant bend at the bend section 9 where the flexibility is significantly enhanced occur. In 7B, the take-up and release mechanism 8 and the manual adjustment device 12 on the handle are manifested as a pair of sliders and a pair of push buttons. The sliders and push buttons are connected and fixed together. The proximal ends of a pair of traction wires 7 are connected and fixed to a pair of sliders. Moving a pair of push buttons can drive a pair of sliders along the axial direction of the high-performance conduit 1, which can also cause a difference in the length of a pair of traction wires 7 remaining in the drawing cavity 6. In 7C, the take-up and release mechanism 8 and the manual adjustment device 12 are manifested as a double-threaded screw and a wheel. The wheel and the wheel are coaxially connected and fixed parallel to the axial direction of the high-performance conduit 1 or are integrated. The proximal ends of a pair of traction wires 7 are respectively connected and fixed to the proximal ends of the double-threaded screw and respectively wound into a pair of threads with opposite directions. Rotating the wheel can drive the double-threaded screw axially to cause one of the traction wires 7 to be wound up and the other traction wire 7 to be unwound, which can also cause a difference in the length of a pair of traction wires 7 remaining in the drawing cavity 6. The above embodiment uses a double-threaded screw and a wheel.

[0031] The above embodiments are only for illustrating the technical concept and features of the present invention. Their purpose is to enable those skilled in the art to understand the content of the present invention and implement it. They should not be used to limit the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A multi-segment steerable curved catheter having an asymmetric curved shape, characterized in that, The invention relates to a multi-segment controllable bending catheter, which comprises a catheter (1) and a control handle (2), the catheter (1) has flexibility at the distal end and is connected to the control handle (2) at the proximal end, the wall thickness of the catheter (1) is sequentially divided into a polymer inner layer (3), a metal reinforcing layer (4) and a polymer outer layer (5) from inside to outside, a pair of wire drawing cavities (6) are arranged between the polymer inner layer (3) and the metal reinforcing layer (4), the pair of wire drawing cavities (6) are symmetrically arranged and penetrate the catheter (1) in the axial direction, a traction wire (7) is arranged in the wire drawing cavity (6), a winding and unwinding mechanism (8) is arranged in the control handle (2), one end of the traction wire (7) is fixed to the distal end of the wire drawing cavity (6), the other end of the traction wire (7) is connected to the winding and unwinding mechanism (8), at least two bending sections with enhanced flexibility are arranged on the distal end of the catheter (1), at least one of the bending sections is an asymmetric bending section, the metal reinforcing layer (4) on the asymmetric bending section is a hypotube (10), the surface of the hypotube (10) is cut to form regularly distributed hollow patterns (11), the hollow patterns (11) on both sides of the asymmetric bending section have inconsistent axial total lengths. The metal reinforcing layer (4) is composed of a whole metal pipe, part of the metal pipe is cut to form a regular hypotube (10) with uniform hollow patterns (11) to form a symmetric bending section, part of the metal pipe is cut to form a hypotube (10) with hollow patterns (11) on both sides having inconsistent axial total lengths to form an asymmetric bending section, and the other part of the metal pipe is cut to form a spiral pipe, a woven pipe or a hypotube with flexibility weaker than that of the symmetric bending section and the asymmetric bending section, the distal end of the catheter (1) is bent towards the side where the traction wire (7) is located from each bending section, and the bending stops after the hollow patterns (11) on the inner side of the catheter (1) are flattened and the pipe walls abut against each other, so that a maximum bending angle is limited, the maximum bending angles of the symmetric bending section in two directions are consistent, the maximum bending angles of the hypotube (10) of the asymmetric bending section in two directions are inconsistent, and the flexibility of each bending section can be differentiated in the design and production process of the multi-segment controllable bending catheter, the size range of the traction force for starting bending and maximum bending of each bending section is adjusted, and the bending sequence of each bending section is controlled. The hollow patterns (11) on the same side of the hypotube (10) of the asymmetric bending section have consistent shapes and sizes and are arranged at equal intervals along the axial direction of the pipe body, the hypotube (10) of the asymmetric bending section has a spiral strip shape, the hollow patterns (11) are open spiral patterns, and the spiral-shaped gap on one side has a width greater than that on the other side.

2. The multi-segment controllably curved catheter with asymmetric curved shape of claim 1, wherein: The winding and unwinding mechanism (8) comprises a screw rod, a wire reel and a sliding block.

3. The multi-segment controllably curved catheter with asymmetric curved shape of claim 2, wherein: The control handle (2) is provided with a hand adjustment device (12), the hand adjustment device (12) is connected to and drives the winding and unwinding mechanism (8), and the hand adjustment device (12) comprises a rotating wheel and a push button.

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