Bending-controllable guiding sheath system

Abstract

The invention provides a controllable bending guide sheath system, and relates to the field of guide sheaths, the controllable bending guide sheath system comprises a controllable bending catheter, a control handle and a traction wire tension adjusting structure, the controllable bending catheter comprises a catheter, a pair of wire drawing cavities are formed in the wall thickness of the catheter in parallel to the axial direction, the pair of wire drawing cavities are symmetrical about the middle axis of the catheter, and traction wires are arranged in the wire drawing cavities; the traction wire tension adjusting structure is arranged in the control handle and comprises a guide rod, the guide rod is sleeved with a sliding block in a sliding mode, the near end of the traction wire is fixedly connected with the sliding block, the guide rod is further sleeved with an elastic buffering piece, and the sliding block is fixedly connected with the elastic buffering piece; the guide rod is provided with a threaded section, the threaded section is in threaded connection with a nut, one end of the elastic buffering piece is connected or contacted with the inner wall of the control handle, and the nut abuts against the other end of the elastic buffering piece. The controllable bending guide sheath system is simplified in structure, smooth in transmission, adjustable in tension and higher in bending precision.

Description

Technical Field

[0001] This invention relates to the field of guide sheath technology, specifically a controllable bending guide sheath system, which is particularly suitable for minimally invasive surgical scenarios requiring precise control, such as cardiovascular and peripheral vascular surgeries. Background Technology

[0002] Existing controllable bending catheters achieve distal bending by driving the traction wire through a control handle, adapting to the complex anatomical structure of the human body. Traditional bidirectional controllable bending catheters often employ a threaded screw structure for their control handles (such as the CN217960935U controllable bending catheter and its control handle). The screw rotation drives the traction wire in the opposite direction, achieving bidirectional bending. However, this structure suffers from direct friction between parts during rotation, high transmission resistance, and non-adjustable traction wire tension. Prolonged use can lead to breakage due to tension fatigue, compromising surgical safety. Summary of the Invention

[0003] The present invention provides a controllable bending guide sheath system to solve any of the technical problems mentioned in the background art.

[0004] To address the aforementioned technical problems, this invention discloses a controllable bending guide sheath system, comprising a controllable bending catheter and a control handle. The controllable bending catheter includes a guide tube, a guide wire is provided in the lumen of the guide tube, and a pair of draw wire cavities are provided parallel to the axial direction in the wall thickness of the guide tube. The pair of draw wire cavities are symmetrical about the central axis of the guide tube and each contains a traction wire. The controllable bending guide sheath system further includes: The tension adjustment structure for the traction wire is located inside the control handle, and the proximal end of the traction wire is connected to the tension adjustment structure for the traction wire.

[0005] Preferably, the traction wire tension adjustment structure includes: A guide rod, on which a slider is slidably sleeved, the proximal end of the traction wire is fixedly connected to the slider, and an elastic buffer is also sleeved on the guide rod, with the slider fixedly connected to the elastic buffer; The guide rod is provided with a threaded section, and a nut is threadedly connected to the threaded section. One end of the elastic buffer is connected to or in contact with the inner wall of the control handle, and the nut presses against the other end of the elastic buffer.

[0006] Preferably, the catheter has a layered composite structure, consisting of a polymer inner layer, a metal reinforcing layer, and a polymer outer layer from the inside out. The metal reinforcement layer is composed of an alloy wire spring coil and an alloy wire braided tube nested together, wherein the braiding density of the braided tube gradually decreases from the near end to the far end.

[0007] Preferably, an annular limiting groove is formed on the inner wall of the knob tube, and a ball bearing is embedded in the annular limiting groove. The outer ring of the ball bearing is interference-fitted with the knob tube, and the inner ring of the ball bearing is clearance-fitted with the screw part. The inner wall of the drawing cavity is coated with a polytetrafluoroethylene lubricating coating.

[0008] Preferably, a keyway is axially formed on the slide rail of the core rod, and a matching guide key is provided on the inner wall of the threaded screw component, so as to restrict the circumferential rotation of the threaded screw component through the keyway cooperation.

[0009] Preferably, it also includes a threaded connection sealing assembly, which includes a medical silicone elastic sealing plug and a metal pressure ring. The metal pressure ring is threadedly connected to the hemostatic valve, and the silicone elastic sealing plug is disposed inside the metal pressure ring. After the metal pressure ring is tightened, it compresses the medical silicone elastic sealing plug to achieve dynamic sealing of the outer wall of the catheter.

[0010] Preferably, a fixing block is provided inside the control handle near the tension adjustment structure of the traction wire, and a through hole is provided inside the fixing block for the traction wire to pass through.

[0011] Preferably, it also includes a tension testing device, which includes: Tension sensor, which is mounted on the traction wire and located inside the control handle, is used to detect the tension of the traction wire; The display is used to show the target bending angle range, test the bending angle, and test the initial tension. The control system is electrically connected to the tension sensor and the display. The control system includes: The acquisition module acquires the reference bending angle range and the target tension range of the traction wire that the catheter needs to be driven to achieve for the current surgery. The correction module determines the target bending angle range after the reference bending angle range is expanded, based on intraoperative dynamic interference pre-compensation. Module 1: The filtering module selects multiple test bending angles from the target bending angle range based on a preset angle gradient; Determination Module: The determination module is used to determine the target initial tension range of the traction wire when the distal end of the catheter is not bent, based on the acquisition module; The second screening module selects multiple initial test tensions from the target initial tension range based on a preset tension gradient.

[0012] Preferably, the tension testing device further includes: Force sensor, with a force measuring layer installed inside the through hole, and a force sensor installed inside the force measuring layer; Distance sensor one is installed at the wiring part of the screw connector and is used to detect the distance of its location from the fixed block along the axis parallel to the screw connector. An angle detection device is used to detect the bending angle of the conduit during tension testing. The sensing block is detachably connected to the top of the conduit. A distance sensor 2 is installed on the side of the sensing block near the nut. The distance sensor 2 is used to detect the distance from its location to the end of the nut near the sensing block along the axis parallel to the guide rod. The control system also includes: The evaluation and determination module is used to determine the bending reliability based on the force sensor detection value and tension sensor detection value corresponding to each test bending angle in the sub-test process; and to determine the initial test tension at which the bending reliability of all sub-test processes is equal to the preset reliability as the target initial tension; each initial test tension corresponds to one sub-test process. The building module is used to construct a mapping table of target initial tension, distance sensor detection value, tension sensor detection value, and angle detection device detection value based on the detection values ​​of the tension sensor and distance sensor 1 during the sub-test process corresponding to the target initial tension, and to display it on the monitor.

[0013] Preferably, during the testing process: First, adjust the nut so that the tension sensor detects different initial test tensions when the distal end of the catheter is not bent. Each initial tension corresponds to a sub-test process, which includes: adjusting the knob to make the actual detection value of the angle detection device different test bending angles, and recording the corresponding detection value of the distance sensor, as well as the corresponding detection values ​​of the force sensor and tension sensor.

[0014] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0015] The tension of the traction wire can be precisely and flexibly adjusted through the cooperation of the guide rod, slider, elastic buffer, and nut. The elastic buffer acts as a buffer during the adjustment process, preventing damage to the catheter or traction wire caused by sudden tension changes. At the same time, the threaded connection of the nut makes the tension adjustment operation convenient and highly accurate, which helps to accurately control the degree of catheter bending.

[0016] The catheter features a layered composite structure: an inner polymer layer, a metal reinforcement layer, and an outer polymer layer, from the inside out. This structure ensures the smoothness of the catheter's inner wall (facilitating the passage of guidewires, etc.) while the metal reinforcement layer 12 enhances the catheter's strength and bending resistance, improving its durability and reliability during surgery. The metal reinforcement layer utilizes an alloy wire spring coil nested within an alloy wire braided tubing, with the braid density gradually decreasing from the proximal end to the distal end. This design allows the proximal end of the catheter to maintain high strength to withstand operational forces, while the distal end is more flexible, facilitating bending and posture adjustment in complex environments such as blood vessels.

[0017] The combination of a medical-grade silicone elastic sealing plug and a metal pressure ring, achieved by tightening the metal pressure ring to compress the sealing plug, provides a dynamic seal to the outer wall of the catheter. This effectively prevents leakage of blood and other bodily fluids during surgery, ensuring a sealed and sterile surgical environment and reducing the risk of infection.

[0018] The ball bearing embedded in the annular limiting groove on the inner wall of the knob tube makes the rotation of the screw part smoother, reduces frictional resistance, and facilitates the operator to perform operations such as bending the catheter; the polytetrafluoroethylene lubricating coating on the inner wall of the drawing chamber can reduce the friction when the traction wire slides in the drawing chamber, making the tension adjustment of the traction wire smoother, while reducing the wear of the traction wire and the drawing chamber, and extending the service life of the instrument.

[0019] The keyway on the core rod slide rail and the guide key on the inner wall of the wire connecting screw restrict the circumferential rotation of the wire connecting screw, ensuring the stability of the structure during operation and avoiding the impact of rotational misalignment on the accuracy of traction wire tension adjustment and guide tube bending control.

[0020] Reduced costs and assembly difficulty: The addition of ball bearings simplifies the handle knob and external connection structure, reducing processing costs and assembly difficulty. Compared with the traditional threaded structure, it greatly improves the feel and reduces manufacturing costs and assembly complexity.

[0021] Improved control precision and safety: The adjustable tension structure of the traction wire avoids the risk of tension fatigue fracture; the density gradient design of the metal reinforcement layer improves the bending precision of the distal end by 15%-20%, and also improves flexibility, reducing irritation to the blood vessel wall.

[0022] Extended service life: Threaded connection sealing components can reduce the amount of sealing materials such as glue, thereby reducing the cost of medical consumables. At the same time, threaded connections are less affected by time factors compared to glue, thus extending their service life. Attached Figure Description

[0023] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings: Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the control handle of the present invention; Figure 3 This is a partial structural diagram of the control handle of the present invention; Figure 4 This is a schematic diagram of the layered composite structure of the present invention; Figure 5 This is a schematic diagram of the keyway and guide key of the present invention; Figure 6 For the present invention Figure 5 A partial structural diagram; Figure 7 This is a schematic diagram of the connection structure between the threaded screw and the slide rail rod of the present invention; Figure 8 This is a schematic diagram of the structure of the sensing block in this invention.

[0024] In the diagram: 1. Catheter; 11. Polymer inner layer; 12. Metal reinforcing layer; 13. Polymer outer layer; 2. Guide wire; 3. Traction wire tension adjustment structure; 31. Guide rod; 311. Threaded section; 32. Slider; 33. Elastic buffer; 34. Nut; 4. Traction wire; 5. Knob tube; 6. Control handle; 7. Wire connecting screw; 71. Screw part; 72. Guide key; 73. Wiring part; 8. Hemostatic valve; 9. Slide rail rod; 91. Keyway; 10. Metal pressure ring; 14. Fixing block; 141. Through hole; 15. Sensing block. Detailed Implementation

[0025] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0026] Furthermore, in this invention, the use of terms such as "first" and "second" is for descriptive purposes only and does not specifically refer to any order or sequence, nor is it intended to limit the invention. They are merely used to distinguish components or operations described using the same technical terms and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions and features of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If a combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0027] The present invention provides the following embodiments: Example 1: This embodiment of the invention provides a controllable bending guide sheath system, such as... Figures 1-7 As shown, it includes: a controllable bending catheter and a control handle 6. The controllable bending catheter includes a catheter 1, a guide wire 2 is provided in the lumen of the catheter 1, and a pair of drawing lumens are provided parallel to the axial direction in the wall thickness of the catheter 1. The pair of drawing lumens are symmetrical about the central axis of the catheter 1 and each contains a traction wire 4. The controllable bending guide sheath system also includes: The tension adjustment structure 3 is installed inside the control handle 6, and the proximal end of the traction wire 4 is connected to the tension adjustment structure 3.

[0028] The tension adjustment structure 3 for the traction wire includes: A guide rod 31 is provided, on which a slider 32 is slidably sleeved. The proximal end of the traction wire 4 is fixedly connected to the slider 32. An elastic buffer 33 (such as a spring) is also sleeved on the guide rod 31, and the slider 32 is fixedly connected to the elastic buffer 33. The guide rod 31 is provided with a threaded section 311, and a nut 34 is threadedly connected to the threaded section 311. One end of the elastic buffer 33 is connected to or in contact with the inner wall of the control handle 6, and the nut 34 presses against the other end of the elastic buffer 33. By rotating and adjusting the nut 34 to compress or release the elastic buffer 33, the initial tension of the traction wire is dynamically adjusted to avoid breakage or bending lag caused by excessive or insufficient tension.

[0029] Among them, the catheter 1 has a layered composite structure, and from the inside out, the catheter 1 consists of a polymer inner layer 11, a metal reinforcing layer 12, and a polymer outer layer 13. The metal reinforcement layer 12 is composed of an alloy wire spring coil and an alloy wire braided tube nested together. The braiding density of the braided tube gradually decreases from the proximal end to the distal end (proximal end density ≥80%, distal end density ≤50%), so as to balance proximal end support and distal end flexibility.

[0030] Among them, an annular limiting groove is opened on the inner wall of the knob tube 5, and a ball bearing is embedded in the annular limiting groove. The outer ring of the ball bearing is interference-fitted with the knob tube 5, and the inner ring of the ball bearing is clearance-fitted with the screw part 71. The inner wall of the drawing cavity is coated with a polytetrafluoroethylene lubricating coating.

[0031] Among them, a keyway 91 is axially opened on the slide rail rod 9 of the core rod, and a matching guide key 72 is set on the inner wall of the wire connecting screw 7. The keyway 91 is used to restrict the circumferential rotation of the wire connecting screw 7, so as to ensure the stability of the traction wire movement direction and avoid bending angle deviation.

[0032] The system also includes a threaded connection sealing assembly, which comprises a medical silicone elastic sealing plug and a metal pressure ring 10. The metal pressure ring 10 is threadedly connected to the hemostatic valve 8, and the silicone elastic sealing plug is disposed inside the metal pressure ring 10. Tightening the metal pressure ring 10 compresses the medical silicone elastic sealing plug, achieving a dynamic seal on the outer wall of the catheter 1. The threaded connection and compression of the sealing plug ensure a stable connection between the catheter and the handle.

[0033] Among them, a fixing block 14 is provided inside the control handle 6 near the tension adjustment structure 3 of the traction wire, and a through hole 141 is provided inside the fixing block 14 for the traction wire 4 to pass through.

[0034] This invention proposes a controllable bending guide sheath system with simplified structure, smooth transmission, adjustable tension, and higher bending accuracy.

[0035] Layered materials: The inner polymer layer 11 is made of medical-grade PEBAX (hardness 72D), the metal reinforcing layer 12 is made of 316L stainless steel spring coil (diameter 0.1mm) and nickel-titanium alloy braided tube (braiding angle 45°), and the outer polymer layer 13 is made of medical-grade PTFE (thickness 0.05mm).

[0036] Traction wire and tensioning mechanism: The traction wire 4 is made of tungsten wire with a diameter of 0.08mm. The near end is connected to the elastic buffer 33 (stainless steel spring, wire diameter 0.2mm, free length 5mm) through nut 34 (M3 specification). Rotating nut 34 can change the spring compression within the range of 0-3mm, corresponding to a tension adjustment range of 5-20N.

[0037] Transmission assembly: An annular limiting groove is opened on the inner wall of the knob tube 5, and a deep groove ball bearing of model 6802 is embedded therein. The outer ring of the bearing is interference-fitted with the knob tube 5, and the inner ring is clearance-fitted with the screw part 71 (clearance 0.02mm) to ensure that there is no circumferential wobble when the screw part 71 slides axially.

[0038] Sealing assembly: The medical silicone elastic sealing plug is made of medical silicone with a Shore hardness of 50. A cross-shaped incision is made in the middle (initial incision width 0.5mm). The metal pressure ring 10 (made of titanium alloy) is connected to the hemostatic valve 8 through an M10 thread. After tightening, the medical silicone elastic sealing plug is compressed to achieve dynamic sealing of the outer wall of the catheter 1 (sealing pressure ≥0.3MPa).

[0039] Working principle: Bending control: Rotating the knob drives the screw section 71 to move axially along the core rod via the ball bearing, thereby pulling two traction wires 4 of different lengths, causing the distal end of the conduit 1 to bend towards the side with less tension; adjusting the nut 34 can preset the initial tension of the traction wire 4 to avoid over-tension or slack.

[0040] Reset mechanism: Rotating the knob tube 5 in the opposite direction resets the screw part 71, releases the tension of the elastic buffer 33, and restores the distal end of the conduit 1 to a straight state under the elastic action of the metal reinforcing layer 12.

[0041] Compared with existing technologies (such as CN217960935U), the core improvement of this invention lies in: A new tension adjustment structure 3 for the traction wire is added to solve the tension fatigue problem; Ball bearing drive is used to reduce knob resistance; The density gradient design of the metal reinforcement layer improves bending accuracy and flexibility; A removable sealing assembly (threaded connection sealing assembly) improves the reusability of the handle.

[0042] The above improvements enhance the overall performance of the product, giving it significant clinical application value and market competitiveness.

[0043] The beneficial effects of the above technical solution are as follows: The tension of the traction wire 4 can be precisely and flexibly adjusted through the cooperation of the guide rod 31, slider 32, elastic buffer 33, and nut 34. The elastic buffer 33 can buffer the tension during the adjustment process, preventing sudden tension changes from damaging the catheter 1 or the traction wire 4. At the same time, the threaded connection of the nut 34 makes the tension adjustment operation convenient and highly accurate, which helps to accurately control the degree of bending of the catheter 1.

[0044] The catheter 1 features a layered composite structure: an inner polymer layer 11, a metal reinforcing layer 12, and an outer polymer layer 13, from the inside out. This structure ensures the smoothness of the inner wall of the catheter 1 (facilitating the passage of the guidewire 2, etc.) while the metal reinforcing layer 12 enhances the strength and bending resistance of the catheter 1, improving its durability and reliability during surgery. The metal reinforcing layer 12 employs an alloy wire spring coil nested within an alloy wire braided tube, with the braiding density gradually decreasing from the proximal end to the distal end. This design allows the proximal end of the catheter 1 to maintain high strength to withstand operational forces, while the distal end is more flexible, facilitating bending and posture adjustment in complex environments such as blood vessels.

[0045] The combination of a medical-grade silicone elastic sealing plug and a metal pressure ring 10, achieved by tightening the metal pressure ring 10 to compress the sealing plug, provides a dynamic seal to the outer wall of the catheter 1. This effectively prevents leakage of blood and other bodily fluids during surgery, ensuring the airtightness and sterility of the surgical environment and reducing the risk of infection.

[0046] The ball bearing embedded in the annular limiting groove on the inner wall of the knob tube 5 makes the rotation of the screw part 71 smoother, reduces frictional resistance, and facilitates the operator to perform operations such as bending the catheter 1; the polytetrafluoroethylene lubricating coating on the inner wall of the drawing chamber can reduce the friction when the traction wire 4 slides in the drawing chamber, making the tension adjustment of the traction wire 4 smoother, while reducing the wear of the traction wire 4 and the drawing chamber, and extending the service life of the instrument.

[0047] The keyway 91 on the core rod slide rail 9 and the guide key 72 on the inner wall of the wire connecting screw 7 restrict the circumferential rotation of the wire connecting screw 7, ensuring the stability of the structure during operation and avoiding the impact of rotational misalignment on the accuracy of tension adjustment of the traction wire 4 and bending control of the guide tube 1.

[0048] Reduced costs and assembly difficulty: The addition of ball bearings simplifies the handle knob and external connection structure, reducing processing costs and assembly difficulty. Compared with the traditional threaded structure, it greatly improves the feel and reduces manufacturing costs and assembly complexity.

[0049] Improved control precision and safety: The adjustable tension structure of the traction wire 4 avoids the risk of tension fatigue fracture; the density gradient design of the metal reinforcement layer 12 improves the distal bending precision by 15%-20% and has better flexibility, reducing irritation to the blood vessel wall.

[0050] Extended service life: Threaded connection sealing components can reduce the amount of sealing materials such as glue, thereby reducing the cost of medical consumables. At the same time, threaded connections are less affected by time factors compared to glue, thus extending their service life.

[0051] Example 2, based on Example 1, combined with Figure 8 It also includes a tension testing device, which includes: A tension sensor is installed on the traction wire 4 and located inside the control handle 6. The tension sensor is used to detect the tension of the traction wire 4. The display is used to show the target bending angle range, test the bending angle, and test the initial tension. The control system is electrically connected to the tension sensor and the display. The control system includes: The acquisition module acquires the reference bending angle range that the traction wire 4 needs to drive the catheter 1 for the current surgery and the target tension range of the traction wire 4 (corresponding to the reference bending angle range). The correction module determines the target bending angle range after the reference bending angle range is expanded, based on intraoperative dynamic interference pre-compensation. Module 1: The filtering module selects multiple test bending angles from the target bending angle range based on a preset angle gradient (which can be 5°). Determination Module: The determination module is used to determine the target initial tension range of the traction wire 4 when the distal end of catheter 1 is not bent, based on the acquisition module; The second screening module selects multiple initial test tensions from the target initial tension range based on a preset tension gradient (which can be 1N).

[0052] The reference bending angle range to be achieved by the traction wire driving the catheter (this is a pre-determined range of bending angles the catheter should reach based on the anatomical structure of the surgical site and the surgical goals), and the target tension range of the traction wire (the tension range that the traction wire needs to provide to ensure that it can drive the catheter to the reference bending angle); the reference bending angle range is mainly determined through preoperative imaging analysis and anatomical studies. The target tension range of the traction wire is primarily determined through mechanical testing and simulation experiments. First, mechanical performance tests are conducted on the catheter and traction wire to understand the material's elastic modulus and bending stiffness, as well as the tensile strength and elasticity of the traction wire. Then, simulation experiments are performed: under conditions similar to the human physiological environment (such as temperature and simulated body fluids), the catheter is placed in a simulated blood vessel or organ model. By adjusting the tension of the traction wire, the bending angle of the catheter is observed. As the tension of the traction wire gradually increases, the tension at which the catheter just bends to the minimum value of the reference bending angle range (e.g., 25°) is recorded; this is the lower limit of the target tension range (e.g., 10N). The tension is further increased, and the tension at which the catheter bends to the maximum value of the reference bending angle range (e.g., 50°) is recorded. Considering a certain safety margin (to avoid excessive tension damaging the catheter or tissue), the upper limit of the target tension range is determined (e.g., 18N). Thus, 10N to 18N constitutes the target tension range of the traction wire capable of driving the catheter to a reference angle of 25° to 50°.

[0053] Correction Module: Considering the dynamic interference during surgery (such as vascular pulsation, slight hand tremors of the operator, etc.), which can affect the consistency between the actual bending angle of the catheter and the theoretical value, the correction module expands the benchmark bending angle range obtained by the acquisition module based on pre-compensation for intraoperative dynamic interference (i.e., pre-estimating the degree of interference). This results in the target bending angle range, reserving a certain error tolerance space for actual operation and ensuring that the catheter can still reach the effective bending range even when interference exists.

[0054] Dynamic interference pre-compensation usually expands the range by 5° to 15° (refer to historical surgical data and experience; or assess the dynamic interference in the surgical area through preoperative imaging methods such as CT, MRI, and angiography). For example, the baseline bending angle range of 30° to 50° is corrected to 25° to 55°. Preoperative imaging techniques such as CT, MRI, and angiography are used to assess the dynamic interference in the surgical area, specifically: If imaging shows strong pulsation in the surgical area (such as in large vessels like the aorta), or significant vascular tortuosity or complex branching, it indicates that dynamic interference has a significant impact on catheter bending, and a larger angle increment (e.g., 12°–15°) should be used. If imaging shows relatively stable vessels in the surgical area with weak pulsation and a straight course, the impact of dynamic interference is small, and a smaller angle increment (e.g., 5°–10°) should be used.

[0055] The module can retrieve pre-stored initial tension ranges determined through experiments or simulation models: Experimental method: In an experimental setup simulating the human body environment, the tension values ​​at which the traction wire does not loosen and the catheter does not deform excessively when the distal end of the catheter is not bent are tested multiple times, and the effective tension range is statistically obtained (e.g., after multiple tests, it is found that 5N~20N can stably meet the requirements). Simulation model method: Using finite element simulation software, the material parameters of the catheter and traction wire, as well as the matching parameters of the guide sheath, are input to simulate the forces acting on the catheter when it is not bent, and the tension range that the traction wire needs to maintain is calculated.

[0056] Then, the module selects an initial tension range that is in a certain proportion (A1, B1) to the target tension range from the basic initial tension range. (In the simulation experiment, the basic proportion (A, B) was tested multiple times to obtain the initial tension range that "the catheter operation is most stable when the basic initial tension is A times the lower limit of the target tension and B times the upper limit of the target tension". This initial tension range is the target initial tension range. ; ; This is the scene complexity coefficient (its value ranges from greater than 0 to less than 1; the more complex the scene, the larger the value). These are the lower and upper adjustment coefficients (both with values ​​greater than 0 and less than 1, and can be [0.1, 0.3] and [0.2, 0.4] respectively); for example: simple scenario (straight blood vessel, weak pulsation): C = 0.3; moderately complex scenario (mildly tortuous blood vessel, moderate pulsation): C = 0.5; highly complex scenario (severely tortuous blood vessel, dense branches, strong pulsation): C = 0.8. The value is greater than 1 and less than 1.3; The value is greater than 0.8 and less than 1; Lower limit of initial target tension range = Lower limit of target tension range × ; Upper limit of initial tension range of target = Upper limit of tension range of target × ; In complex scenarios, increasing the lower limit of the target initial tension range prevents catheters and other instruments from bending and failing due to excessively low tension, ensuring operational effectiveness. Conversely, in complex scenarios, decreasing the upper limit of the target initial tension range prevents instrument damage or excessive deformation due to excessive tension, ensuring operational safety.

[0057] Assuming the lower limit of the target tension range is 10N, and the scale group is (1.2, 0.8), first calculate 1.2 times the lower limit of the target tension range: 10N × 1.2 = 12N, so we take 12N as the lower limit of the initial target tension range. Next, calculate 0.8 times the upper limit of the target tension range: 18N × 0.8 = 14.4N. Therefore, the initial target tension range is 12N~14.4N.

[0058] The basic proportion group [A, B] can be obtained through experimental or simulation model methods. Experimental method: In an experimental device simulating the human body environment, the tension of the traction wire "without loosening and without causing excessive deformation of the catheter" when the distal end of the catheter is not bent is tested multiple times. The effective tension range is statistically obtained and then converted into a basic ratio group.

[0059] Simulation model method: Using finite element simulation software, input the materials of the catheter, traction wire and guide sheath, simulate and calculate the tension range that the traction wire needs to maintain to allow the catheter to work normally, and then convert it into a basic proportional group.

[0060] The beneficial effects of the above technical solution are as follows: By defining the target initial tension range of the traction wire when the distal end of the catheter is not bent by the module, the tension state of the traction wire in the initial stage of the operation can be accurately set, providing a stable and appropriate starting point for subsequent catheter bending operations, avoiding difficulties in subsequent adjustments due to improper initial tension, and ensuring the stability of the operation at the beginning.

[0061] Module 1 and Module 2 select multiple test bending angles and initial test tensions based on preset gradients. These test data can simulate catheter bending under different surgical scenarios. Combined with the results displayed on the monitor, operators can clearly understand the matching effect of different tensions and angles, thus providing a direct and effective reference for adjusting the tension of the traction wire and the bending angle of the catheter in actual surgery, improving the accuracy and efficiency of the adjustment.

[0062] Pre-operative testing using a tension testing device allows for the initial screening and verification of the combination of traction wire tension and catheter bending angle before the actual surgical procedure. This reduces the time spent on repeated adjustments due to unsuitable parameters during surgery, resulting in smoother surgical procedures and improved overall surgical efficiency.

[0063] Example 3, based on Example 2, further includes the tension testing device: A force sensor is provided, with a force measuring layer inside the through hole 141, and a force sensor is provided inside the force measuring layer; wherein, the force sensor can be set in the wear area of ​​the traction wire 4 that is prone to wear inside the through hole 141 (such as the area entering and leaving the through hole 141). Distance sensor 1 is installed at the wiring part 73 of the screw connector 7. Distance sensor 1 is used to detect the distance of its location from the fixing block 14 along the axis parallel to the screw connector 7. An angle detection device is used to detect the bending angle of the conduit 1 during the tension test; The sensing block 15 is detachably connected to the top of the conduit 1. A distance sensor 2 is provided on the side of the sensing block 15 near the nut 34. The distance sensor 2 is used to detect the distance from its location to the end of the nut 34 near the sensing block 15 along the axis parallel to the guide rod 31. The control system also includes: The evaluation and determination module is used to determine the bending reliability based on the force sensor detection value and tension sensor detection value corresponding to each test bending angle in the sub-test process; and to determine the initial test tension at which the bending reliability of all sub-test processes is equal to the preset reliability (e.g., 0.85 to 0.95) as the target initial tension; each initial test tension corresponds to one sub-test process. The module is used to construct a mapping table based on the target's initial tension, the distance sensor's detection value, the distance sensor's detection value, and the angle detection device's detection value during the sub-test process. This mapping table is a multi-parameter correlation table used to intuitively present the correspondence between the key parameters of "target initial tension," "distance sensor's detection value," "tension sensor's detection value," and "angle detection device's detection value."

[0064] During the testing process (for in vitro detection): First, adjust nut 34 so that the tension sensor detects different initial test tensions when the distal end of conduit 1 is not bent. Each initial test tension corresponds to a sub-test process, which includes: adjusting knob tube 5 so that the actual detection value of the angle detection device is different test bending angles, and recording the corresponding distance sensor detection value, as well as the corresponding force sensor detection value and tension sensor detection value.

[0065] The force sensor reading is within the preset allowable force range. If the force sensor detection value is 1, then the reliability is 1; preset allowable force range: in the experimental device simulating the human body environment, test the force threshold that the wear area of ​​the traction wire can withstand (e.g., after multiple tests, take the "force range that does not break / excessive deformation"). The tension sensor readings fall within the target tension range of traction wire 4. If the reliability of the tension sensor's detection value is 1, then the reliability of the detection value is 1. The reliability corresponding to the i-th test bending angle in the current sub-test process is ; ; These are the force sensor readings for the i-th test bending angle in the current sub-test process (when there are multiple force sensors). (Take the maximum value of all force sensors) and the detection value of the tension sensor; for The corresponding minimum allowed value; for The corresponding minimum allowed value; These are the first reliability weight and the second reliability weight, respectively; the first reliability weight + the second reliability weight = 1, and both the first reliability weight and the second reliability weight take values ​​greater than 0 and less than 1; The bending reliability of the current sub-test process is: ; ; These are bending reliability weight one, bending reliability weight two, and bending reliability weight three (the sum of the three is 1, and all three values ​​are greater than 0 and less than 1, and...). maximum); It is the absolute value of the maximum permissible force sensor reading deviation between two consecutive test bending angles; M represents the absolute value of the maximum permissible deviation of the tension sensor readings between two consecutive test bending angles; M is the total number of temperature-measuring bending angles in the current sub-test process. The weight corresponding to the "mean reliability of each angle" reflects the core impact of the force and tension adaptability at a single angle on the overall reliability. It is usually set to the maximum value (e.g., 0.5 to 0.7) because the basic reliability of a single angle is the foundation of the overall assessment. The weight of the "average deviation of the tension sensor detection value" reflects the influence of the tension fluctuation of the traction wire as the "driving source" on the bending accuracy of the catheter. The value is secondary (e.g., 0.2 to 0.3). If the tension of the traction wire is a key control parameter (e.g., catheter shaping), it can be appropriately increased.

[0066] The weight corresponding to the "average deviation of force sensor detection value" reflects the impact of the reaction force on the risk of damage to the catheter as the "force-receiving end". The value is secondary (e.g., 0.1 to 0.2), which is suitable for surgical scenarios that are sensitive to force control (such as delicate vascular operations).

[0067] The beneficial effects of the above technical solution are as follows: Force sensors are placed in areas prone to wear on the traction wire, accurately detecting the force exerted on the wire at critical wear points. Distance sensors one and two detect distance changes in relevant components, aiding in determining the position and movement of the catheter, etc. An angle detection device accurately acquires the bending angle of the catheter. Multiple sensors collect data from different dimensions, working together to significantly improve the accuracy of detecting catheter bending and traction wire stress, providing a more accurate basis for subsequent reliability calculations and determination of the target initial tension.

[0068] By setting the reliability of the force sensor's detection value to 1 when it is within a preset allowable force range and the tension sensor's detection value to be within the target tension range of the traction wire, and then combining this with weighted calculations of bending reliability, the stress and tension safety of the catheter during bending can be comprehensively evaluated. Only the initial tension of the test when the bending reliability of all sub-test processes reaches the preset value (e.g., 1) is determined as the target initial tension. This effectively avoids problems such as damage to the traction wire and catheter caused by improper force or tension, ensuring surgical safety.

[0069] The module generates and displays a mapping table of tension sensor detection values ​​and angle detection device detection values ​​based on the sub-test process corresponding to the initial target tension. In actual surgery, operators can quickly determine the corresponding bending angle of the catheter using this mapping table and the tension sensor detection values, facilitating timely adjustments, improving surgical accuracy and efficiency, and reducing operational difficulty.

[0070] The testing process is conducted externally, allowing for comprehensive testing of different initial tensions and bending angles before the actual surgery. This enables the selection of a suitable target initial tension before surgery, avoiding repeated adjustments due to unsuitable parameters during the operation, reducing surgical risks, and also making the surgical procedure smoother.

[0071] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A controllable bending guiding sheath system, comprising a controllable bending catheter and a control handle (6), the controllable bending catheter comprising a catheter (1), a guide wire (2) being arranged in a lumen of the catheter (1), and a pair of pull wire cavities being arranged in parallel with the axial direction in the wall thickness of the catheter (1), the pair of pull wire cavities being symmetrical about the central axis of the catheter (1) and each being internally provided with a pull wire (4), characterized in that: The controllable bending guide sheath system further comprises: A traction wire tension adjusting structure (3) is arranged in the control handle (6), and the proximal end of the traction wire (4) is connected with the traction wire tension adjusting structure (3).

2. The steerable bend guide sheath system of claim 1, wherein: The traction wire tension adjusting structure (3) comprises: A guide rod (31) is sleeved with a sliding block (32) on the guide rod (31), the proximal end of the traction wire (4) is fixedly connected with the sliding block (32), and the guide rod (31) is further sleeved with an elastic buffer (33), and the sliding block (32) is fixedly connected with the elastic buffer (33); A threaded segment (311) is arranged on the guide rod (31), a nut (34) is threadedly connected on the threaded segment (311), one end of the elastic buffer (33) is connected with or in contact with the inner wall of the control handle (6), and the other end of the elastic buffer (33) is pressed by the nut (34).

3. The steerable bend guide sheath system of claim 1, wherein: The catheter (1) is of a layered composite structure, and the catheter (1) comprises, from inside to outside, a polymer inner layer (11), a metal reinforcing layer (12) and a polymer outer layer (13). The metal reinforcing layer (12) is formed by nesting of an alloy wire spring ring and an alloy wire braided tube, wherein the braiding density of the braided tube gradually decreases from the proximal end to the distal end.

4. The steerable bend guide sheath system of claim 1, wherein: An annular limiting groove is formed in the inner wall of the knob tube (5), a ball bearing is embedded in the annular limiting groove, the outer ring of the ball bearing is in interference fit with the knob tube (5), and the inner ring of the ball bearing is in clearance fit with the screw rod portion (71). The inner wall of the wire drawing cavity is coated with a polytetrafluoroethylene lubricating coating.

5. The steerable bend guide sheath system of claim 1, wherein: A key groove (91) is axially formed on the sliding rail rod (9) of the core rod, a matching guide key (72) is arranged on the inner wall of the wire connecting screw rod member (7), and the key groove (91) is matched to limit the circumferential rotation of the wire connecting screw rod member (7).

6. The steerable bend guide sheath system of claim 1, wherein: Further comprising a threaded connection sealing assembly, the threaded connection sealing assembly comprises: a medical silica gel elastic sealing plug and a metal compression ring (10), the metal compression ring (10) is threadedly connected with the hemostatic valve (8), and the silica gel elastic sealing plug is arranged on the inner side of the metal compression ring (10); after the metal compression ring (10) is screwed, the medical silica gel elastic sealing plug is compressed to realize dynamic sealing of the outer wall of the catheter (1).

7. The steerable bend guide sheath system of claim 1, wherein: A fixed block (14) is arranged in the control handle (6) close to the traction wire tension adjusting structure (3), a through hole (141) is arranged in the fixed block (14), and the through hole (141) is used for passing the traction wire (4).

8. The steerable bend guide sheath system of claim 7, wherein: Further comprising a tension testing device, the tension testing device comprises: A tension sensor is arranged on the traction wire (4) and in the control handle (6), and the tension sensor is used for detecting the tension of the traction wire (4); A display is used for displaying a target bending angle range, a test bending angle and a test initial tension; A control system is electrically connected with the tension sensor and the display, and the control system comprises: An acquisition module acquires a reference bending angle range for driving the catheter (1) by the traction wire (4) and a target tension range of the traction wire (4) for a current operation; A correction module determines a target bending angle range after expansion of the reference bending angle range based on intraoperative dynamic interference pre-compensation. The first screening module selects a plurality of test bending angles from the target bending angle range based on a preset angle gradient; The determining module is configured to determine a target initial tension range of the pull wire (4) when the distal end of the catheter (1) is not bent based on the acquisition module; The second screening module selects a plurality of test initial tensions from the target initial tension range based on a preset tension gradient.

9. The steerable bend guide sheath system of claim 8, wherein: The tension testing device further comprises: The force sensor is arranged in the through hole (141) and the force sensor is arranged in the force measuring layer; The first distance sensor is arranged on the wire connecting portion (73) of the wire connecting screw member (7) and is configured to detect the distance from the fixed block (14) along the axial direction of the wire connecting screw member (7); The angle detection device is configured to detect the bending angle of the catheter (1) during the tension testing process; The sensing block (15) is detachably connected to the top end of the catheter (1), and the second distance sensor is arranged on the side of the sensing block (15) close to the nut (34) and is configured to detect the distance from the end of the nut (34) close to the sensing block (15) along the axial direction of the guide rod (31); The control system further comprises: The evaluation and determination module is configured to determine the bending reliability based on the force sensor detection value and the tension sensor detection value corresponding to each test bending angle during the sub-test process, and to determine the test initial tension as the target initial tension when the bending reliability of all sub-test processes is equal to the preset reliability; each test initial tension corresponds to a sub-test process; The construction module is configured to construct a mapping table of the target initial tension-distance sensor one detection value-tension sensor detection value-angle detection device detection value based on the tension sensor detection value, the distance sensor one detection value, and the angle detection device detection value during the sub-test process corresponding to the target initial tension, and to display the mapping table through the display.

10. The controllable bending guide sheath system according to claim 9, wherein: During the test process: First, adjust the nut (34) so that the tension sensor detection value is different for the test initial tension when the distal end of the catheter (1) is not bent; Each test initial tension corresponds to a sub-test process, and the sub-test process includes adjusting the knob tube (5) so that the actual detection value of the angle detection device is different for the test bending angle, and recording the corresponding distance sensor one detection value and recording the corresponding force sensor detection value and tension sensor detection value.

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