Bending-adjustable micro catheter with multi-section bending control function

Abstract

The invention provides a bending-adjustable microcatheter with multi-section bending control, and belongs to the technical field of bending-adjustable microcatheters.The bending-adjustable microcatheter with the multi-section bending control comprises a catheter body, a driving assembly and a control assembly, and the catheter body is composed of seven flexible pipe sections which are connected with one another; the driving assembly comprises seven independent shape memory alloy drivers, and each shape memory alloy driver is connected with the outer side of the corresponding flexible pipe section. The control assembly comprises a power supply, a microprocessor and a temperature sensor, the power supply supplies power to the shape memory alloy drivers, the microprocessor controls the current of each shape memory alloy driver, and the temperature sensor monitors the temperature of each flexible pipe section in real time; the problems that the bendability of a traditional catheter is usually limited, the catheter can only be operated within a fixed angle range, the bending form of the catheter is fixed, and various surgical operation requirements cannot be perfectly met can be solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of adjustable bend micro-catheters, and in particular, relates to an adjustable bend micro-catheter with multi-section bending control. Background Art

[0002] The adjustable microcatheter is a highly flexible and precisely controlled catheter system designed for medical applications. It is mainly used in minimally invasive surgery or interventional treatment to help doctors accurately access complex parts of the patient's body (such as blood vessels, cavities, luminal organs, etc.). Compared with traditional rigid catheters, the adjustable microcatheter has higher operational flexibility and better adaptability. It can bend and adjust according to different anatomical structures and treatment needs, thereby achieving more precise treatment.

[0003] In recent years, minimally invasive surgery and interventional treatment have been widely used, especially in the fields of endoscopy and gastrointestinal surgery. Traditional catheter systems are often unable to adapt to complex and narrow lesions due to their high rigidity and limited operating range, resulting in poor treatment effects and even increased trauma and complications for patients. Therefore, developing a catheter system that can freely adjust its bending shape according to needs has become an important direction for the development of medical technology.

[0004] The bendability of traditional catheters is usually limited and can only be operated within a fixed angle range. The bending shape of the catheter is relatively fixed and cannot perfectly adapt to various surgical operation requirements. Summary of the invention

[0005] In view of this, the present invention provides an adjustable microcatheter with multi-stage bending control, which can solve the problem that the bending of traditional catheters is usually limited and can only be operated within a fixed angle range, the bending shape of the catheter is relatively fixed, and it cannot perfectly adapt to various surgical operation requirements.

[0006] The present invention is achieved in that: The present invention provides an adjustable bend micro-catheter with multi-segment bending control, which includes a catheter body, a drive component and a control component. The catheter body is composed of 7 interconnected flexible pipe segments; the drive component includes 7 independent shape memory alloy drivers, each shape memory alloy driver is connected to the outer side of the corresponding flexible pipe segment; the control component includes a power supply, a microprocessor and a temperature sensor, the power supply supplies power to the shape memory alloy driver, the microprocessor controls the current of each shape memory alloy driver, and the temperature sensor monitors the temperature of each flexible pipe segment in real time.

[0007] The microprocessor in the control unit uses a PID control algorithm to adjust the current of each SMA driver in real time according to the temperature information fed back by the temperature sensor, so as to achieve precise control of the bending angle of each flexible pipe section. The PID control algorithm can effectively suppress temperature fluctuations and external interference, and improve the accuracy and stability of bending control.

[0008] A graphical user interface (GUI) is integrated into the control unit. The GUI displays a 3D model of the catheter and allows the user to control the catheter's bending shape via a mouse or touch screen. The GUI also displays information such as the temperature, current, and bending angle of each flexible tube segment, making it easy for the user to monitor the catheter's working status.

[0009] On the basis of the above technical solution, the adjustable bend microcatheter with multi-section bend control of the present invention can also be improved as follows: Among them, each shape memory alloy actuator is composed of two shape memory alloy wires, which are respectively wound on both sides of the flexible tube segment; when current passes through the shape memory alloy wire, the shape memory alloy wire contracts, driving the flexible tube segment to bend.

[0010] Furthermore, each flexible tube segment is made of nickel-titanium alloy and has shape memory effect and superelasticity, so that each flexible tube segment can restore a preset shape at a specific temperature, while still maintaining the ability of elastic deformation within a larger deformation range, thereby achieving bending and resetting of the catheter.

[0011] Furthermore, a connector is provided between two adjacent flexible pipe sections, the connector is in a circular ring shape, the inner diameter of the connector matches the outer diameter of the flexible pipe section, and is used to connect the two adjacent flexible pipe sections and ensure the integrity and sealing of the conduit; The connector is made of medical grade PEEK.

[0012] Furthermore, the flexible pipe segment has a corrugated structure, and annular grooves are evenly distributed on the surface of each flexible pipe segment. The depth of the annular grooves is 0.05 mm, and the spacing between the annular grooves is 0.5 mm; the annular grooves are used to increase the flexibility of the flexible pipe segment and provide a fixed position for winding the shape memory alloy wire; the shape memory alloy wire is wound in the annular groove, and the two ends of the shape memory alloy wire are respectively fixed to the two ends of the flexible pipe segment by micro metal buckles, and the micro metal buckles are made of stainless steel material and have a diameter of 0.2 mm. The micro metal buckles fix the shape memory alloy wire by pressing.

[0013] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: by arranging evenly distributed annular grooves on the surface of the flexible pipe segment to form a corrugated structure, the overall flexibility of the flexible pipe segment is enhanced, and at the same time, a stable winding positioning is provided for the shape memory alloy wire to prevent the shape memory alloy wire from being displaced during operation; the micro metal clip is made of stainless steel material and fixes the two ends of the shape memory alloy wire by pressing, ensuring that the shape memory alloy wire can reliably drive the flexible pipe segment to bend when contracted, thereby improving the stability and accuracy of the microcatheter bending control.

[0014] Furthermore, an annular groove is provided on the inner wall of the connector, and the depth of the annular groove is 0.1mm and the width is 0.5mm; an annular protrusion is provided at the end of the flexible tube segment, and the height of the annular protrusion is 0.1mm and the width is 0.5mm; the annular protrusion of the flexible tube segment is snapped into the annular groove of the connector to form a snap-on structure; a medical-grade epoxy resin adhesive is also coated between the connector and the flexible tube segment to enhance the connection strength and ensure the sealing; two symmetrically distributed wire through holes are provided on the outer wall of the connector, and the diameter of the wire through holes is 0.2mm, and the inner walls of the wire through holes are coated with insulating material.

[0015] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: the annular groove on the inner wall of the connector and the annular protrusion on the end of the flexible tube section form a precise clamping structure, which can maintain the overall flexibility while ensuring a firm connection; the use of medical-grade epoxy resin adhesive further enhances the connection strength and ensures the overall sealing of the microcatheter, preventing blood from seeping into the catheter; the symmetrically distributed wire through holes on the outer wall of the connector cooperate with the inner wall insulating coating to provide a safe channel for the wires of the shape memory alloy driver, effectively preventing short circuits between the wires and metal parts, and improving the safety of the microcatheter.

[0016] Furthermore, the front end tube section of the catheter body is a conical structure, the proximal diameter of the conical tube section is the same as other flexible tube sections, which is 1 mm, the distal diameter is 0.5 mm, and the length is 7 mm; the conical tube section is made of a composite material of nickel-titanium alloy and platinum alloy with a weight ratio of 7:3, which is used to improve the flexibility and developability of the front end of the catheter; the surface of the conical tube section is coated with a polyvinyl alcohol hydrophilic coating with a coating thickness of 0.01 mm; four side holes are opened at the front end of the conical tube section, the side holes are circular with a diameter of 0.2 mm, and the four side holes are evenly distributed on the circumference of the conical tube section at 90 degrees.

[0017] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: the conical tube section is made of a 7:3 composite material of nickel-titanium alloy and platinum alloy, which not only retains the superelasticity of nickel-titanium alloy, but also utilizes the high density characteristics of platinum alloy to enhance the development effect under X-rays, making it easier for doctors to accurately position during surgery; the conical structure design makes it easier for the front end of the catheter to pass through narrow or curved blood vessels; the polyvinyl alcohol hydrophilic coating significantly reduces the friction between the catheter and the blood vessel wall; the four circumferentially evenly distributed side hole design provides a multi-directional drug release channel to ensure that the drug can be evenly diffused to the target area.

[0018] Furthermore, the seven flexible tube segments are, from the proximal end to the distal end, the first tube segment, the second tube segment, the third tube segment, the fourth tube segment, the fifth tube segment, the sixth tube segment and the seventh tube segment; the lengths of the first tube segment and the seventh tube segment are both 7 mm, and the lengths of the second tube segment, the third tube segment, the fourth tube segment, the fifth tube segment and the sixth tube segment are all 5 mm; the wall thickness of the first tube segment and the seventh tube segment is 0.12 mm, and the wall thickness of the second tube segment, the third tube segment, the fourth tube segment, the fifth tube segment and the sixth tube segment is 0.10 mm; the flexible tube segments are connected by connecting pieces, the axial length of the connecting pieces is 1 mm, and the wall thickness of the connecting pieces is 0.15 mm; the bending stiffness of the flexible tube segments gradually decreases from the proximal end to the distal end.

[0019] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: by accurately designing the length and wall thickness parameters of the seven flexible tube segments, a structural gradient is formed in which the bending stiffness gradually decreases from the proximal end to the distal end, so that the catheter has good pushing and tracking properties during the advancement process; the first tube segment and the seventh tube segment adopt a longer design, which respectively provides a stable connection with the control handle and precise positioning capability of the front end; the middle five tube segments adopt the same length and wall thickness, ensuring the overall consistency and controllability of the catheter; the connecting parts adopt a larger wall thickness design, which enhances the connection strength between the tube segments and prevents separation during use.

[0020] Compared with the prior art, the beneficial effects of the multi-section bending controlled adjustable microcatheter provided by the present invention are: The catheter body consists of 7 flexible tube segments, which are connected to each other by connectors to form a whole. Each tube segment is made of nickel-titanium alloy, which has shape memory effect and super elasticity, and can restore the preset shape at a specific temperature while maintaining elasticity within a large deformation range.

[0021] Each tube segment is a hollow cylinder with an outer diameter of 1mm, an inner diameter of 0.8mm and a length of 5mm, which ensures the small size and flexibility of the catheter and is suitable for operations in complex environments, such as intravascular insertion.

[0022] Two adjacent pipe sections are connected by connectors made of medical-grade polyetheretherketone material. These connectors are in the shape of a ring, and the inner diameter matches the outer diameter of the flexible pipe section, thereby ensuring the sealing and integrity between the pipe sections.

[0023] The drive assembly consists of 7 independent shape memory alloy (SMA) actuators, each of which is connected to the outside of the corresponding flexible pipe segment through a wound shape memory alloy wire. When current passes through the shape memory alloy wire, the shape memory alloy wire will contract, thereby driving the flexible pipe segment to bend. Each SMA actuator consists of two shape memory alloy wires, which are wound on both sides of the flexible pipe segment to ensure uniform bending. Through current control, the contraction and recovery of the SMA wire can accurately control the bending angle of each pipe segment.

[0024] The power supply adjusts the temperature by controlling the current of each SMA actuator, thereby precisely controlling the bending angle of each flexible tube segment. The current intensity is directly related to the temperature, so the control of the current determines the degree of bending and recovery ability of each tube segment.

[0025] The microprocessor uses a PID control algorithm to adjust the current of each SMA driver in real time based on the temperature information fed back by the temperature sensor. The PID algorithm can effectively eliminate temperature fluctuations and external interference, improve the accuracy and stability of control, and enable the catheter to maintain precise bending control under different working environments.

[0026] The temperature sensor monitors the temperature of each flexible pipe section in real time, and the feedback information is used by the microprocessor to adjust the current to ensure the consistency of temperature and bending control.

[0027] The integrated GUI allows users to control the bending shape of the catheter through a touch screen or mouse. The GUI can display the 3D model of the catheter in real time and show data such as temperature, current and bending angle of each flexible tube segment. This not only makes it convenient for users to monitor the working status of the catheter, but also provides intuitive feedback to facilitate adjustment of the shape of the catheter.

[0028] By precisely designing the length and wall thickness parameters of the seven flexible tube segments, a structural gradient is formed in which the bending stiffness gradually decreases from the proximal end to the distal end, so that the catheter has good pushing and tracking properties during the advancement process; the first and seventh tube segments adopt a longer design, which respectively provides a stable connection with the control handle and precise positioning capability of the front end; the middle five tube segments use the same length and wall thickness to ensure the overall consistency and controllability of the catheter; the connector adopts a larger wall thickness design to enhance the connection strength between the tube segments and prevent separation during use. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative labor.

[0030] Figure 1 It is a schematic diagram of the structure of an adjustable bending microcatheter with multi-segment bending control; Figure 2 It is a structural schematic diagram of the flexible pipe section; In the accompanying drawings, the components represented by the reference numerals are listed as follows: 10. Catheter body; 20. Drive assembly; 30. Control assembly. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solution and advantages of the embodiments of the present invention more clear, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0032] like Figure 1-2 As shown, it is a schematic structural diagram of an adjustable bend microcatheter with multi-segment bending control provided by the present invention. In the figure, it includes a catheter body 10, a drive assembly 20 and a control assembly 30. The catheter body 10 is composed of 7 interconnected flexible pipe segments; the drive assembly 20 includes 7 independent shape memory alloy drivers, each shape memory alloy driver is connected to the outer side of the corresponding flexible pipe segment; the control assembly 30 includes a power supply, a microprocessor and a temperature sensor. The power supply supplies power to the shape memory alloy driver, the microprocessor controls the current of each shape memory alloy driver, and the temperature sensor monitors the temperature of each flexible pipe segment in real time.

[0033] Among them, in the above technical solution, each shape memory alloy actuator is composed of two shape memory alloy wires, which are respectively wound on both sides of the flexible pipe segment; when current passes through the shape memory alloy wire, the shape memory alloy wire contracts and drives the flexible pipe segment to bend.

[0034] Furthermore, in the above technical solution, each flexible tube segment is made of nickel-titanium alloy, which has shape memory effect and superelasticity, so that each flexible tube segment can restore a preset shape at a specific temperature, while still maintaining the ability of elastic deformation within a larger deformation range, thereby realizing the bending and resetting of the catheter.

[0035] Furthermore, in the above technical solution, a connector is provided between two adjacent flexible pipe sections, the connector is in a circular ring shape, the inner diameter of the connector matches the outer diameter of the flexible pipe section, and is used to connect the two adjacent flexible pipe sections and ensure the integrity and sealing of the conduit; The connector is made of medical grade PEEK.

[0036] Furthermore, in the above technical solution, the flexible pipe segment has a corrugated structure, and annular grooves are evenly distributed on the surface of each flexible pipe segment. The depth of the annular grooves is 0.05 mm, and the spacing between the annular grooves is 0.5 mm; the annular grooves are used to increase the flexibility of the flexible pipe segment and provide a fixed position for winding the shape memory alloy wire; the shape memory alloy wire is wound in the annular groove, and the two ends of the shape memory alloy wire are respectively fixed to the two ends of the flexible pipe segment by micro metal clips, and the micro metal clips are made of stainless steel material with a diameter of 0.2 mm. The micro metal clips fix the shape memory alloy wire by pressing.

[0037] Furthermore, in the above technical solution, an annular groove is provided on the inner wall of the connector, and the depth of the annular groove is 0.1 mm and the width is 0.5 mm; an annular protrusion is provided at the end of the flexible tube segment, and the height of the annular protrusion is 0.1 mm and the width is 0.5 mm; the annular protrusion of the flexible tube segment is snapped into the annular groove of the connector to form a snap-on structure; a medical-grade epoxy resin adhesive is also coated between the connector and the flexible tube segment to enhance the connection strength and ensure the sealing; two symmetrically distributed wire through holes are provided on the outer wall of the connector, and the diameter of the wire through holes is 0.2 mm, and the inner walls of the wire through holes are coated with insulating material.

[0038] Furthermore, in the above technical solution, the front end tube section of the catheter body is a conical structure, the proximal diameter of the conical tube section is the same as other flexible tube sections, which is 1 mm, the distal diameter is 0.5 mm, and the length is 7 mm; the conical tube section is made of a composite material of nickel-titanium alloy and platinum alloy with a weight ratio of 7:3, which is used to improve the flexibility and developability of the front end of the catheter; the surface of the conical tube section is coated with a polyvinyl alcohol hydrophilic coating with a coating thickness of 0.01 mm; four side holes are opened at the front end of the conical tube section, the side holes are circular with a diameter of 0.2 mm, and the four side holes are evenly distributed on the circumference of the conical tube section at 90 degrees.

[0039] Furthermore, in the above technical scheme, the seven flexible pipe segments are, from the proximal end to the distal end, the first pipe segment, the second pipe segment, the third pipe segment, the fourth pipe segment, the fifth pipe segment, the sixth pipe segment and the seventh pipe segment; the lengths of the first pipe segment and the seventh pipe segment are both 7 mm, and the lengths of the second pipe segment, the third pipe segment, the fourth pipe segment, the fifth pipe segment and the sixth pipe segment are all 5 mm; the wall thickness of the first pipe segment and the seventh pipe segment is 0.12 mm, and the wall thickness of the second pipe segment, the third pipe segment, the fourth pipe segment, the fifth pipe segment and the sixth pipe segment is 0.10 mm; the flexible pipe segments are connected by connecting pieces, the axial length of the connecting pieces is 1 mm, and the wall thickness of the connecting pieces is 0.15 mm; the bending stiffness of each flexible pipe segment gradually decreases from the proximal end to the distal end.

[0040] Embodiment 1: In coronary intervention, doctors need to use a catheter to enter the coronary arteries of the heart to perform vascular dilation, stent implantation and other treatments. However, due to the complex structure of the coronary arteries and their location in the heart, traditional catheters often have difficulty flexibly navigating accurately in the complex vascular network.

[0041] The adjustable microcatheter in this embodiment adopts multi-segment bending control technology, and the catheter can independently adjust the bending angle in multiple segments. This allows the catheter to accurately adjust its shape when passing through the coronary artery to adapt to complex vascular pathways and narrow areas.

[0042] Each section of the catheter is made of shape memory alloy material, which can bend automatically according to the change of current or temperature. Doctors can precisely change the bending angle of each section of the catheter by adjusting the controller. For example, when the catheter passes through the right coronary artery, the doctor can adjust the angle of the catheter according to the curvature of the blood vessel to ensure that the catheter does not touch the blood vessel wall and passes smoothly through the narrow blood vessel area.

[0043] When entering a narrow area, the front section of the catheter can bend more, while the rear section remains relatively straight to ensure that the catheter can smoothly enter the deep blood vessels. The degree of curvature of each section is adjusted by electric current, allowing the catheter to fully adapt to the complex vascular morphology.

[0044] Built-in sensors in the catheter monitor the current, temperature and bending angle in real time to ensure that the catheter is always in a safe state and prevent damage to the catheter or the diseased area due to excessive heating or bending.

[0045] The application of this technology can make coronary intervention more precise, reduce patient trauma and improve the success rate of surgery. Doctors can accurately navigate in complex coronary arteries to avoid excessive operations and unnecessary injuries.

[0046] Embodiment 2: During digestive tract endoscopy (such as gastroenteroscopy and colonoscopy), doctors need to insert an endoscopic catheter through the patient's esophagus, stomach or colon for examination. Due to differences in the morphology and structure of the patient's digestive tract, traditional endoscopic catheters sometimes have difficulty adapting to different physiological curves, resulting in difficulty in insertion and may even cause trauma to the patient.

[0047] The adjustable microcatheter of this embodiment is used for gastrointestinal endoscopic examination, and its design can flexibly adjust the shape of the catheter to ensure precise operation when entering the complex and curved digestive tract.

[0048] Each section of the catheter is made of shape memory alloy material. The catheter adjusts the current according to the information fed back by the sensor and controls the bending shape of the catheter by changing the temperature. For example, when passing through the esophagus, the front section of the catheter is relatively straight, and when the catheter enters the stomach, the back section can bend to adapt to the natural shape of the stomach.

[0049] The catheter's curvature control is divided into multiple sections, and the front and rear sections can be adjusted independently. For example, during a colonoscopy, the front section of the catheter can be flexibly adjusted according to the curvature of the colon, while the rear section remains relatively straight to facilitate smooth passage through complex intestinal pathways.

[0050] The endoscope catheter is equipped with a temperature sensor to monitor the catheter temperature in real time to avoid damage to the diseased area caused by overheating. The temperature change of the catheter causes the shape memory alloy material to return to the required shape, ensuring that the catheter passes through complex areas without causing damage to the diseased tissue.

[0051] This catheter technology can not only significantly improve the flexibility of endoscopic examinations, but also reduce patient discomfort caused by difficult catheter insertion, reduce surgical risks and reduce damage to the digestive tract during operations.

[0052] Embodiment 3: In cerebrovascular interventional treatments, such as the treatment of cerebral aneurysms, doctors need to use catheters to enter the brain's blood vessels for angioplasty or stent implantation. Due to the complex and narrow paths of brain blood vessels, traditional rigid catheters are difficult to perform precise operations, especially in curved arteries or small blood vessels.

[0053] The adjustable bend microcatheter in this embodiment is specially designed for cerebrovascular interventional treatment and adopts multi-segment bending control technology to cope with the complexity of cerebrovascular vessels.

[0054] The catheter is made of shape memory alloy material, which can change the bending angle according to the different vascular morphology when passing through the cerebral blood vessels. For example, when passing through a large curved area of ​​the artery, the front section of the catheter can bend more significantly, while the rear section remains relatively straight to reduce friction and avoid damage to the blood vessel wall.

[0055] When entering the brain blood vessels, each section of the catheter can be adjusted independently. The front section bends to adapt to the more complex blood vessel curvatures, while the rear section remains straight, ensuring that the catheter accurately reaches the target site during the entire treatment process.

[0056] The catheter is equipped with an intelligent feedback system that monitors the intravascular pressure, temperature and bending angle in real time to ensure that the catheter works within a safe range. For example, during treatment, the system automatically adjusts the current according to the state of the cerebral blood vessels to maintain the stability and flexibility of the catheter in the blood vessels.

[0057] This adjustable microcatheter technology can provide more precise navigation, helping doctors operate in narrow and tortuous cerebral blood vessels, reducing surgical trauma and risks, and improving the success rate of treatment.

[0058] Specifically, the principle of the present invention is: when in use, ensure that the various components of the catheter system are intact and firmly connected. Connect the connector of the catheter system to the external power supply and control unit. Check whether the power supply is stable and whether the current control system is normal. Start the control system and check the feedback data of the temperature sensor to ensure that the temperature range is suitable for the operation requirements. Insert the front end of the catheter system into the target area (such as blood vessels, cavities, etc.) in the patient's body. Select the desired catheter bending angle and shape through the graphical user interface (GUI). Set the degree of bending of each tube segment according to surgical requirements or treatment plans. Adjust the current through the touch screen or mouse interface to control the contraction of the shape memory alloy driver, thereby changing the bending angle of each section of the catheter. The system will automatically adjust the current and temperature according to the PID control algorithm to keep the catheter in a stable bending shape. Observe the real-time feedback on the GUI interface to view the three-dimensional model, temperature, current and bending angle of the catheter. The shape of the catheter can be adjusted according to the feedback to accurately meet the operation requirements. Ensure that the temperature of each tube segment is kept within a safe range to avoid equipment failure or discomfort caused by overheating or overcooling. Ensure that there is no discomfort or damage during operation. The catheter should be cleaned, disinfected and properly maintained immediately after use. Ensure that the catheter is in good working condition after each use.

Claims

1. A multi-stage bending controlled adjustable microcatheter, characterized in that: The invention comprises a catheter body (10), a drive assembly (20) and a control assembly (30), wherein the catheter body (10) is composed of 7 interconnected flexible pipe sections; the drive assembly (20) comprises 7 independent shape memory alloy drivers, each of which is connected to the outer side of a corresponding flexible pipe section; the control assembly (30) comprises a power supply, a microprocessor and a temperature sensor, wherein the power supply supplies power to the shape memory alloy driver, the microprocessor controls the current of each shape memory alloy driver, and the temperature sensor monitors the temperature of each flexible pipe section in real time.

2. The adjustable bend microcatheter with multi-section bend control according to claim 1, characterized in that: Each shape memory alloy actuator consists of two shape memory alloy wires, which are respectively wound around the two sides of the flexible tube segment; when current passes through the shape memory alloy wires, the shape memory alloy wires contract, driving the flexible tube segment to bend.

3. The adjustable bend microcatheter with multi-section bend control according to claim 2, characterized in that: Each flexible tube segment is made of nickel-titanium alloy and has shape memory effect and superelasticity, which is used to enable each flexible tube segment to restore a preset shape at a specific temperature, while still maintaining the ability of elastic deformation within a larger deformation range, thereby achieving the bending and repositioning of the catheter.

4. The adjustable bend microcatheter with multi-section bend control according to claim 3, characterized in that: A connecting piece is provided between two adjacent flexible pipe sections. The connecting piece is in a circular ring shape, and its inner diameter matches the outer diameter of the flexible pipe section. The connecting piece is used to connect the two adjacent flexible pipe sections and ensure the integrity and sealing of the conduit. The connector is made of medical grade PEEK.

5. The adjustable bend microcatheter with multi-section bend control according to claim 4, characterized in that: The flexible pipe section has a corrugated structure, and annular grooves are evenly distributed on the surface of each flexible pipe section. The depth of the annular grooves is 0.05 mm, and the spacing between the annular grooves is 0.5 mm; the annular grooves are used to increase the flexibility of the flexible pipe section and provide a fixed position for winding the shape memory alloy wire; the shape memory alloy wire is wound in the annular groove, and the two ends of the shape memory alloy wire are respectively fixed to the two ends of the flexible pipe section by micro metal buckles, the micro metal buckles are made of stainless steel material and have a diameter of 0.2 mm, and the micro metal buckles fix the shape memory alloy wire by pressing.

6. The adjustable bend microcatheter with multi-section bend control according to claim 5, characterized in that: An annular groove is provided on the inner wall of the connector, and the depth of the annular groove is 0.1mm and the width is 0.5mm; an annular protrusion is provided at the end of the flexible tube segment, and the height of the annular protrusion is 0.1mm and the width is 0.5mm; the annular protrusion of the flexible tube segment is snapped into the annular groove of the connector to form a snap-on structure; a medical-grade epoxy resin adhesive is also coated between the connector and the flexible tube segment to enhance the connection strength and ensure the sealing; two symmetrically distributed wire through holes are provided on the outer wall of the connector, and the diameter of the wire through holes is 0.2mm, and the inner walls of the wire through holes are coated with insulating material.

7. The adjustable bend microcatheter with multi-section bend control according to claim 6, characterized in that: The front end tube section of the catheter body is a conical structure, the proximal diameter of the conical tube section is the same as other flexible tube sections, which is 1 mm, the distal diameter is 0.5 mm, and the length is 7 mm; the conical tube section is made of a composite material of nickel-titanium alloy and platinum alloy with a weight ratio of 7:3, which is used to improve the flexibility and developability of the front end of the catheter; the surface of the conical tube section is coated with a polyvinyl alcohol hydrophilic coating with a coating thickness of 0.01 mm; four side holes are opened at the front end of the conical tube section, the side holes are circular with a diameter of 0.2 mm, and the four side holes are evenly distributed on the circumference of the conical tube section at 90 degrees.

8. The adjustable bend microcatheter with multi-section bend control according to claim 7, characterized in that: The seven flexible tube segments are, from the proximal end to the distal end, the first tube segment, the second tube segment, the third tube segment, the fourth tube segment, the fifth tube segment, the sixth tube segment and the seventh tube segment; the lengths of the first tube segment and the seventh tube segment are both 7 mm, and the lengths of the second tube segment, the third tube segment, the fourth tube segment, the fifth tube segment and the sixth tube segment are all 5 mm; the wall thickness of the first tube segment and the seventh tube segment is 0.12 mm, and the wall thickness of the second tube segment, the third tube segment, the fourth tube segment, the fifth tube segment and the sixth tube segment is 0.10 mm; the flexible tube segments are connected by connecting pieces, the axial length of the connecting pieces is 1 mm, and the wall thickness of the connecting pieces is 0.15 mm; the bending stiffness of the flexible tube segments gradually decreases from the proximal end to the distal end.

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