Guide structure, ureter sheath and ureter insertion device

Abstract

The invention discloses a guiding structure, a ureter sheath and a ureter insertion device, and belongs to the technical field of medical instruments.The guiding structure comprises a guiding pipe, a guiding cavity channel penetrating in the axial direction is formed in the guiding pipe, and a spiral groove extending in the axial direction in a spiral mode is formed in the inner wall of the guiding cavity channel; a spiral tube; the cladding body wraps the peripheral wall of the spiral pipe in a closed mode along the extending path of the wire of the spiral pipe, and the cladding body is embedded in the spiral groove in the extending direction of the spiral groove; and the guide pipe and the cladding body are embedded with each other to form the inner peripheral wall of the guide cavity channel. Compared with the prior art, the ureter sheath has the advantages that the phenomenon of inner layer swelling can be effectively reduced, and then the technical problem that in the related technology, the ureter sheath affects the smoothness of instrument insertion is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and particularly relates to a guiding structure, a ureteral sheath and a ureteral insertion device. Background Art

[0002] A ureteral sheath is a medical device widely used in urological surgeries, usually composed of an outer tube, an intermediate spiral tube (also called a spring tube) and an inner tube. The design of this device aims to provide a certain supporting force to establish a passage for an endoscope and other instruments to enter the urinary tract, enabling the urinary catheter to be smoothly introduced into the ureter.

[0003] Through long-term practice, the inventor found that during the operation, the inner layer of the ureteral sheath often bulges, which in turn affects the smoothness of instrument insertion. Summary of the Invention

[0004] The present invention discloses a guiding structure, a ureteral sheath and a ureteral insertion device to solve the technical problem that the ureteral sheath in the related art affects the smoothness of instrument insertion.

[0005] To solve the above problems, the present invention adopts the following technical solutions: In a first aspect, the present invention discloses a guiding structure of a ureteral sheath, including: a guiding tube having an axially penetrating guiding cavity therein, and the inner wall of the guiding cavity forms an axially helically extending spiral groove; a spiral tube; a cladding body which is closed and coated on the outer peripheral wall of the spiral tube along the extending path of the wire of the spiral tube, wherein the cladding body is embedded in the spiral groove along the extending direction of the spiral groove; after the guiding tube and the cladding body are mutually embedded, they jointly form the inner peripheral wall of the guiding cavity.

[0006] In a second aspect, the present invention further discloses a ureteral sheath including the guiding structure described in the first aspect.

[0007] In a third aspect, the present invention further discloses a ureteral insertion device, including the guiding structure described in the first aspect or the ureteral sheath described in the second aspect; Or, including the guiding structure described in the first aspect or the ureteral sheath described in the second aspect, and further including a lens assembly disposed at the distal end of the ureteral sheath.

[0008] The technical solutions adopted by the present invention can achieve the following beneficial effects: The present invention provides a tightly fitted structure between the spiral tube and the cladding body, and uses a spiral tube with a rectangular cross-section, so that the matching degree between the cladding body and the spiral groove is higher, thereby providing a limiting effect in the radial direction and reducing the dislocation or sliding of the cladding body caused by external forces during use. In addition, the cladding body is provided with different inclined surfaces at the first right-angle part and the second right-angle part respectively, so that it can be kept in close contact with the spiral groove, improving its radial fixing effect. When the guiding tube is bent by an external force, since the cladding body and the spiral tube form a good fitting relationship, delamination, dislocation or bulging will not easily occur, thus ensuring the overall structural stability of the guiding tube. In addition, by reasonably designing the gradient relationship of the thermal expansion coefficient, the spiral tube, the cladding body and the guiding tube can expand or contract coordinately when the temperature changes, avoiding the problem of interface delamination or peeling caused by excessive thermal stress difference, further enhancing the structural support ability of the guiding tube, so that it still maintains a stable shape during bending and dynamic operation, meeting the requirements of medical operations; To reduce the material fatigue or damage of the guiding tube caused by stress concentration during use, the present invention introduces a fillet surface structure at specific parts of the cladding body, especially at the second right-angle part of the cladding body with a rectangular cross-section, using a fillet transition, thereby reducing the local stress concentration effect. When the guiding tube passes through a narrow or complex cavity, it may generate large local stress due to bending. The existence of the fillet surface can make the stress more evenly distributed over the entire structure, avoiding excessive force on a single part and resulting in cracks or breakages. In addition, the design of the third inclined surface makes it so that when the guiding tube bends and deforms, the protrusion formed by the dislocation of the joint surface between the cladding body and the spiral groove does not form a sharp obstruction, but smoothly transitions along the direction of the guiding cavity, so that the medical device will not be significantly affected by resistance during the insertion process, thereby reducing the risk of damage. Combined with the bonding texture on the surface of the spiral tube, this structural design not only improves the bonding force between the cladding body and the spiral tube, but also prevents the interface separation of the material due to long-term use or temperature changes to a certain extent, thus effectively extending the service life of the guiding tube and improving the reliability of its clinical application; The present invention adopts reasonable material selection and bonding methods in the guiding tube structure, making the combination between different layers more stable, while enhancing biocompatibility and usability. As the inner layer in contact with medical fluids, the cladding body can be made of polyethylene or PTFE materials to provide good chemical stability and low friction characteristics, reducing the sliding resistance of medical devices in the lumen. The outermost guiding tube can be made of polyurethane or PEBAX materials, which not only have good flexibility but also can provide a certain supporting effect, while the intermediate helical tube can be made of metal materials to enhance the overall shape retention ability. In addition, the cladding body and the guiding tube can be coated with a biocompatible adhesive, thereby increasing the bonding area on the outer side and both end sides, improving the interface strength, and reducing interlayer peeling caused by long-term use or temperature changes. It should be noted that the bonding texture on the surface of the helical tube further enhances the fixing effect of the cladding body, enabling it to remain stable under stress or temperature changes and preventing the cladding body from slipping or deforming in the helical groove. These optimized designs not only improve the durability of the guiding tube but also make it smoother during clinical operations, increasing the success rate of surgeries and the safety of patients. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0010] Figure 1 is a schematic structural diagram of the guiding structure of the ureteral sheath in some embodiments of the present application; Figure 2 is a partial cross-sectional view of the guiding structure of the ureteral sheath in some embodiments of the present application; Figure 3 is a partial connection cross-sectional view of the guiding tube, helical tube, and cladding body in some embodiments of the present application Figure 1 ; Figure 4 is Figure 3 a partial connection cross-sectional view of the helical tube and cladding body shown in Figure 5 is a partial connection cross-sectional view of the guiding tube, helical tube, and cladding body in some embodiments of the present application Figure 2 ; Figure 6 is a partial connection cross-sectional view of the guiding tube, helical tube, and cladding body in some embodiments of the present application Figure 3 ; Figure 7 is a partial connection cross-sectional view of the guiding tube, helical tube, and cladding body in some embodiments of the present applicationFigure 4 ; Figure 8 is a partial connection cross-section of a guiding tube, a spiral tube, and a cladding body in some embodiments of the present application Figure 5 .

[0011] In the figure: 100, guiding tube; 110, guiding cavity; 120, spiral groove; 130, filling limiting part; 200, spiral tube; 210, first right-angle part; 220, second right-angle part; 300, cladding body; 310, rounded chamfer surface; 320, first inclined surface; 330, second inclined surface; 340, third inclined surface. Detailed implementation manners

[0012] To make the objectives, technical solutions, and advantages of the present invention clearer, the technical solutions of the present invention will be described in detail below. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other implementation manners obtained by those of ordinary skill in the art without creative efforts fall within the scope protected by the present invention.

[0013] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, rather than to describe a specific order or sequence. It should be understood that such used data may be interchanged under appropriate circumstances so that the embodiments of the present application can be implemented in an order other than those illustrated or described herein, and the objects distinguished by "first", "second", etc. are usually of the same category, and do not limit the number of objects. For example, the first object may be one or multiple. In addition, "and / or" in the specification and claims means at least one of the connected objects, and the character " / " generally represents an "or" relationship between the associated objects before and after.

[0014] In each embodiment of the present application, "proximal end" and "distal end" refer to the relative distances of each component from the user in the usage environment. Among them, the end closer to the user is designated as the "proximal end", and the end farther from the user is designated as the "distal end".

[0015] In the related art, a ureteral guiding sheath is a medical device widely used in urological surgeries, usually composed of an outer tube body, a spiral tube (also called a spring tube) in the middle layer, and an inner tube body. The design of this device aims to enable the urethral catheter to be smoothly introduced into the ureter by providing a certain supporting force. However, in practice, the phenomenon of inner layer bulging often occurs. Especially after long-term use, the delamination problem between the inner tube body and the outer tube body becomes particularly significant. After in-depth research, the applicant found that the root cause of the inner tube body bulging phenomenon is the delamination between the outer tube body and the inner tube body, and this problem stems from multiple structural defects in the existing design.

[0016] First, the joint surface between the inner and outer tube bodies of the ureteral guiding sheath is not smooth and continuous. Instead, due to the structural characteristics of the intermediate spiral tube, an uneven contact surface is formed. Specifically, the joint surface between the metal and the glue of the spiral tube shows a periodic variation law, which leads to obvious differences in strength and area in the joint area. Due to this periodic variation, the bonding force between the inner and outer tube bodies is uneven in different regions. Especially when bent or stressed, it is easy to detach from the weak connection points. This detachment gradually expands from a small range and finally causes the bulging phenomenon of the inner tube body. Therefore, the structural characteristics of the spiral tube and the periodic variation of the metal-glue joint surface are the main factors leading to the delamination and detachment of the inner and outer tube bodies.

[0017] Second, the wire rod of the spiral tube as the intermediate layer has the problem of forward and backward crosstalk displacement during use. This displacement leads to a change in the pitch of the spiral tube, and further causes the uneven connection quality between the inner and outer tube bodies. The change in pitch not only affects the stability of the connection between the inner and outer tube bodies, but also exerts a shear force on the joint surface during the change process. The action of the shear force will exacerbate the peeling between the inner and outer tube bodies, thus further aggravating the occurrence of the bulging of the inner tube body. Even in the absence of obvious external forces, the change in pitch itself can cause a slight detachment between the inner and outer tube bodies, and gradually deteriorate with the extension of the use time, ultimately affecting the overall performance of the ureteral guiding sheath.

[0018] In the prior art, due to the failure to effectively solve the problems of uneven combination and pitch change caused by the spiral tube structure, the inner tube body of the ureteral guiding sheath often bulges and the inner and outer tube bodies delaminate and detach during use. This not only affects its reliability and stability in clinical operations, but also may have an adverse impact on the treatment process of patients. Therefore, there is an urgent need for a new structural design that can effectively avoid or slow down the problem of detachment of the inner and outer tube bodies and improve the smoothness of the ureteral guiding sheath during instrument insertion.

[0019] Based on this, the present application provides a guiding structure, a ureteral sheath and a ureteral insertion device.

[0020] The following combines the attached Figures 1 to 8 , and through specific embodiments and their application scenarios, a guiding structure, a ureteral sheath and a ureteral insertion device provided by the present application are described in detail.

[0021] In the first aspect, in combination with Figure 1 , Figure 2 and Figure 3, the present application provides a guiding structure, which is applied to a ureteral sheath and includes a guiding tube 100, a spiral tube 200, and a cladding body 300. Among them, the guiding tube 100 has an axially penetrating guiding cavity 110, and the inner wall of the guiding cavity 110 forms an axially helically extending spiral groove 120. At the same time, the cladding body 300 is closed and coated on the outer peripheral wall of the spiral tube 200 along the extension path of the wire of the spiral tube 200. Furthermore, the cladding body 300 is embedded in the spiral groove 120 along the extension direction of the spiral groove 120, and after the guiding tube 100 and the cladding body 300 are mutually embedded, they jointly form the inner peripheral wall of the guiding cavity 110.

[0022] Exemplarily, when manufacturing the guiding structure, first wrap a layer of the cladding body 300 around the wire of the spiral tube 200, then produce the spiral tube 200, and then combine the guiding tube 100 with the spiral tube 200 coated with the cladding body 300 by extrusion molding or hot melting process. In this way, the cladding body 300 and the guiding tube 100 can jointly provide the inner peripheral wall of the guiding cavity 110, and at the same time, the spiral tube 200 coated with the cladding body 300 can also be embedded into the spiral groove 120 of the guiding tube 100.

[0023] On this basis, the guiding structure of the ureteral sheath realizes a more stable interlayer bonding effect by optimizing the coating method of the spiral tube 200 and the structural design of the guiding tube 100, thereby reducing the inner tube bulging and interlayer detachment phenomena caused by the structural problems of the spiral tube 200 in the prior art.

[0024] First of all, the inner wall of the guiding tube 100 is designed with an axially helically extending spiral groove 120, which is used to accommodate the spiral tube 200 and the cladding body 300, making its overall structure more stable. The spiral tube 200 serves as a supporting structure for the middle layer, and the surface of its wire is coated with the cladding body 300. The cladding body 300 is closed and coated on its outer peripheral wall along the extension path of the wire of the spiral tube 200, and the cladding body 300 matches the spiral groove 120 during the manufacturing process and is embedded into the spiral groove 120 of the guiding tube 100. Such a structural design makes the spiral tube 200 not simply embedded in the guiding tube 100, but jointly form an embedded structure with the cladding body 300. This embedding method enhances the overall stability of the guiding structure to a certain extent, reduces the displacement change problem of the spiral tube 200 caused by force or long-term use, and is beneficial to maintaining the long-term use performance of the ureteral sheath.

[0025] Secondly, through the design of the cladding body 300, the bonding quality between the helical tube 200 and the guiding tube 100 can be effectively improved. As a cladding structure, the cladding body 300 can enclose the outer periphery of the helical tube 200, so that the helical tube 200 is not directly exposed in the inner cavity of the guiding tube 100. In this way, the axial continuity of the cladding body 300 can, to a certain extent, reduce the shearing effect caused by the pitch change of the helical tube 200. In other words, when the ureteral sheath is bent or stressed, the wire of the helical tube 200 is not likely to apply excessive shearing force to the bonding part between the guiding tube 100 and the cladding body 300, which helps to reduce the risk of interlayer delamination. In addition, the presence of the cladding body 300 can limit each part of the helical tube 200 within the cladding range of the cladding body 300 even if local fracture occurs, so as to maintain the basic channel shape and avoid the situation that the fractured part is displaced or affects the passage of instruments in the guiding lumen 110.

[0026] In addition, this guiding structure can also improve the inner surface quality of the guiding lumen 110. In the prior art, due to the limitation of the bonding method between the metal material of the helical tube 200 and the coating rubber layer, the inner wall of the ureteral sheath often has periodic unevenness, which may lead to an increase in the resistance during the passage of instruments and affect the guiding effect. In the present invention, by completely covering the helical tube 200 with the cladding body 300 and forming a matching fit with the helical groove 120 of the guiding tube 100, the bonding interface of the inner wall presents a more uniform rubber-rubber bonding surface instead of a metal-rubber bonding surface. This can, to a certain extent, reduce the unevenness of the interface transition, lower the delamination risk caused by the difference in the bonding force of different materials, and make the inner wall of the guiding lumen 110 smoother, which is beneficial to improving the smoothness of instrument insertion.

[0027] In the production and manufacturing process, this structural design also has a positive impact. Since the helical tube 200 is wrapped with a cladding body 300, its overall axial compression resistance performance is optimized. When the guiding tube 100 and the helical tube 200 are combined, the cladding body 300 can provide a certain buffering effect, so that the helical tube 200 maintains a relatively fixed pitch during the assembly process, thereby reducing the quality instability problem caused by pitch change during the production process. In addition, the presence of the cladding body 300 enables the guiding tube 100 to distribute stress more evenly to a certain extent, reduces the risk of interlayer delamination caused by local stress concentration, and improves the overall structural stability of the ureteral sheath.

[0028] In summary, by optimizing the cladding structure of the spiral tube 200 and the design of the guiding tube 100, the optimization of the interlayer bonding is achieved, making the guiding structure less likely to delaminate and separate during long-term use. At the same time, the surface quality of the guiding channel 110 is improved, the smoothness of instrument insertion is enhanced, and the stability of the overall structure is strengthened. In this way, to a certain extent, the problems of delamination and bulging existing in the existing ureteral sheath guiding structure are solved, providing more reliable technical support for clinical operations.

[0029] In some embodiments, in combination with Figure 2 、 Figure 3 , the structural design of the guiding tube 100 is further optimized. A filling and limiting portion 130 is formed on the guiding tube 100 and between the spiral segments of adjacent cladding bodies 300 to limit the distance between the spiral segments of adjacent cladding bodies 300, and also to a certain extent limit the movement range of the spiral tube 200 and the cladding body 300, improving the stability of the overall structure. Exemplarily, the filling and limiting portion 130 is actually the part of the guiding tube 100 between the spiral segments of adjacent cladding bodies 300, and this part structurally forms a local limit on the cladding body 300, thereby playing a certain buffering and limiting role in the axial displacement of the spiral tube 200 and the cladding body 300.

[0030] During the actual use of the ureteral sheath, since the guiding tube 100 may be bent, twisted and subjected to external pressure, the spiral tube 200 and its cladding body 300 may undergo slight axial displacement. If the displacement range is too large, it may cause uneven changes in the pitch of the spiral tube 200, thereby affecting the overall performance of the guiding structure. In this embodiment, the setting of the filling and limiting portion 130 can provide filling support between adjacent spiral segments, so that the movement of the spiral tube 200 and the cladding body 300 in the axial direction is restricted to a certain extent, thereby reducing the structural instability problem caused by pitch changes. In addition, the filling and limiting portion 130 can also play a certain buffering role. Under the action of external forces, it helps to reduce the stress concentration of the spiral tube 200 and the cladding body 300, reduce the risk of interlayer peeling, and improve the durability of the ureteral sheath during long-term use.

[0031] Furthermore, since the filling and limiting portion 130 is a part of the guiding tube 100, its material and form can be optimized according to actual needs. For example, a material with a certain elasticity or flexibility can be selected, so that while providing a limiting effect, it can still allow elastic deformation within a certain range, thereby achieving a balance between structural stability and flexibility. This design not only helps to maintain the guiding performance of the ureteral sheath, but also can reduce unnecessary displacement of the spiral tube 200 that may occur in a dynamic environment, improving the smoothness and comfort during instrument insertion.

[0032] In some embodiments, with reference toFigure 2 , Figure 3 as well as Figure 4 The cross-sectional shape of the wire of the spiral tube 200 is designed to be rectangular, and the cross-sectional shape of the cladding body 300 is embedded and matched with the cross-sectional shape of the wire of the spiral tube 200 in the circumferential direction, thereby improving the stability and adaptability of the embedding to a certain extent. Further, the spiral tube 200 has two first right-angle portions 210 and two second right-angle portions 220, wherein the first right-angle portion 210 is located on one side of the spiral tube 200 close to the guide channel 110, and the second right-angle portion 220 is located on the other side of the spiral tube 200 away from the guide channel 110.

[0033] After such arrangement, compared with the traditional circular or elliptical cross-section, the wire of the spiral tube 200 with a rectangular cross-section can provide a more stable contact interface during the embedding process. Specifically, the four right-angled parts of the rectangular structure can form a larger area of ​​contact with the cladding body 300, thereby reducing relative slippage to a certain extent and improving the covering and fixing effect of the cladding body 300 on the spiral tube 200. In addition, since the rectangular cross-section can provide a better support effect when subjected to force, when the guide tube 100 is bent or subjected to external pressure, the deformation of the spiral tube 200 is relatively controllable, which can better maintain the uniformity of the spiral pitch, thereby helping to reduce the risk of interlayer delamination caused by uneven pitch.

[0034] At the same time, after being coated by the cladding body 300, the spiral tube 200 with a rectangular cross-section can provide a more regular structural support, making the inner wall shape of the guide cavity 110 more uniform, reducing the resistance to instrument insertion that may be caused by the uneven inner wall surface, and improving the smoothness of the guidance. At the same time, the first right-angle portion 210 of the rectangular structure is located on the side close to the guide cavity 110, so that the inner wall of the guide cavity 110 is smoother under the support of the spiral tube 200, and the second right-angle portion 220 is located on the side away from the guide cavity 110, which can form a more stable embedded support in the guide tube 100, reducing the possibility of displacement or deformation of the spiral tube 200 due to force during use. Therefore, this design optimizes the structural stability while also improving the overall performance of the ureteral sheath.

[0035] In some embodiments, in combination Figure 2 , Figure 5 The outer wall surface of the corner of the second right-angle portion 220 of the spiral tube 200 corresponding to the cladding body 300 is configured as a chamfered surface 310, so that the guide tube 100 also forms a chamfered surface 310 at the corresponding position of the chamfered surface 310 of the cladding body 300, so as to alleviate the stress concentration problem to a certain extent and reduce the possibility of cracks or damage to the guide tube 100 in this area.

[0036] Exemplarily, the linear distance between the starting point of the rounded corner surface 310 and the central axis of the guiding channel 110 is greater than or equal to the linear distance between the second right-angle portion 220 and the central axis of the guiding channel 110. This means that the transition region of the rounded corner surface 310 is relatively outward in geometric distribution, enabling the cladding body 300 to form a relatively smooth structural transition here and avoiding local stress concentration caused by right-angle mutations.

[0037] Exemplarily, the thickness of the cladding body 300 corresponding to the rounded corner surface 310 is greater than or equal to the thickness of the cladding body 300 corresponding to the relative part of the surface of the spiral tube 200, thereby enhancing the structural strength of this part to a certain extent, endowing it with better load-bearing capacity when stressed, and reducing the risk of cracking caused by fatigue accumulation.

[0038] Exemplarily, the radius of the rounded corner surface 310 is less than or equal to the thickness of other parts of the cladding body 300, ensuring that effective stress buffering can still be provided in this area without excessively increasing the overall wall thickness.

[0039] In practical applications, the ureteral guiding sheath needs to be advanced within the narrow and curved ureter and withstand pressures from different directions. In this case, if a right-angle design is adopted for the corner area of the cladding body 300, it may cause this part to become a weak link of stress concentration. Especially under repeated bending or long-term use, phenomena such as material fatigue or even microcrack propagation are more likely to occur. In this embodiment, by adopting the rounded corner surface 310 structure for the corner area of the cladding body 300, the stress distribution in this area becomes more uniform, which helps to reduce the local stress peak value and improve the structural stability of the guiding tube 100 in a dynamic environment.

[0040] In addition, the thickness of the cladding body 300 in the area of the rounded corner surface 310 is set to be greater than or equal to the thickness of the relative part of the surface of the spiral tube 200, further enhancing the mechanical strength of this area. Under the action of external forces, this area can provide better support, reduce the deformation caused by the outer layer being stressed, and improve the smoothness of the ureteral sheath during insertion. At the same time, since the radius of the rounded corner surface 310 is less than or equal to the thickness of other parts of the cladding body 300, it is ensured that the curvature of this area will not be too large so as not to affect the compactness and flexibility of the overall structure. Generally speaking, this optimized design can improve the durability of the guiding structure while reducing the impact of stress concentration on the integrity of the outer layer structure, and enhance the stability and reliability of the ureteral guiding sheath in clinical use.

[0041] In some alternative embodiments, in combination with Figure 2 、 Figure 6, the outer wall surface of the cladding body 300 corresponding to the corner of the first right-angle portion 210 is configured as a first inclined surface 320, and the first inclined surface 320 is always in contact with the spiral groove 120. Through such a design, the cladding body 300 is limited in the radial direction, enabling it to be more stably embedded in the spiral groove 120.

[0042] Specifically, the setting of the first inclined surface 320 enables the cladding body 300 to be in close contact with the spiral groove 120 of the guiding tube 100 in the radial direction after being embedded in the spiral groove 120. This contact relationship reduces to a certain extent the possibility of axial or radial displacement of the cladding body 300 during use, improving the stability between the cladding body 300 and the spiral tube 200. At the same time, compared with the right-angle transition structure, the inclined surface design of the first inclined surface 320 helps to reduce local stress concentration, making the cladding body 300 less likely to deform or peel when stressed, thereby enhancing the durability and reliability of the guiding structure.

[0043] In some other alternative embodiments, in combination with Figure 2 , Figure 7 , the outer wall surface of the cladding body 300 corresponding to between the first right-angle portion 210 and the second right-angle portion 220 is configured as a second inclined surface 330, and the second inclined surface 330 is inclined in a direction away from the first right-angle portion 210 or the second right-angle portion 220, and the second inclined surface 330 is always in contact with the spiral groove 120. Through such a design, the cladding body 300 is limited in the radial direction, enabling it to be more stably embedded in the spiral groove 120.

[0044] Specifically, the design of the second inclined surface 330 can provide an additional limiting effect, enabling the cladding body 300 to better fit the spiral groove 120 axially, thereby further enhancing the stability of the cladding body 300 on the surface of the spiral tube 200. Since the second inclined surface 330 is inclined in a direction away from the first right-angle portion 210 or the second right-angle portion 220, this structure can optimize the fitting relationship between the spiral tube 200 and the guiding tube 100 to a certain extent, reducing the micro-displacement of the cladding body 300 due to stress during long-term use. At the same time, since the second inclined surface 330 is always in contact with the spiral groove 120, this contact relationship can provide more stable mechanical support, enabling the cladding body 300 to remain stable even under large bending deformations.

[0045] In some embodiments, such as Figure 2 , Figure 8As shown, a third inclined surface 340 is disposed on the outer wall surface of the corner corresponding to a first right-angle portion 210 near the proximal side of the cladding body 300. In the axial direction from the proximal end to the distal end of the guiding channel 110, the included angle formed by the third inclined surface 340 facing the extension line of the guiding channel 110 and the central axis of the guiding channel 110 is an acute angle. Exemplarily, the third inclined surface 340 also always remains in contact with the inner wall of the spiral groove 120. The design of this structure can effectively improve the misalignment of the joint surface between the cladding body 300 and the spiral groove 120 when the guiding tube 100 is bent, which may affect the insertion of the instrument. It should be noted that Figure 8 The arrow shown below indicates the insertion direction of the instrument from the proximal end to the distal end in the guiding channel 110.

[0046] Specifically, when the guiding tube 100 is bent in the human body cavity, the third inclined surface 340 of the cladding body 300 may undergo slight deformation due to local stress concentration in the spiral tube 200. Especially during the bending process, there may be a slight misalignment between the third inclined surface 340 and the spiral groove 120, thus forming a protrusion on the inner surface of the guiding channel 110. If these protrusions face the inside of the guiding channel 110, they may cause a certain degree of obstruction to the instrument inserted therein. However, since the third inclined surface 340 provided in this embodiment is inclined along the extension line direction of the guiding channel 110 and forms an acute angle with the central axis of the guiding channel 110, when the protrusion is formed, its surface is still smoothly transitioned and is generally consistent with the direction of instrument insertion.

[0047] The advantage of this structure is that even if the cladding body 300 is misaligned in a local area, the formed protrusions do not form significant stepped obstacles, but gradually rise along the axis direction of the guiding channel 110 to form a relatively smooth transition surface. This smooth structure helps to reduce the resistance caused by the protrusions during the instrument insertion process, enabling the instrument to pass through more smoothly. At the same time, when the distal part of the instrument contacts the protrusion, due to the surface of the protrusion being consistent with the insertion direction, the instrument can push it flat or push it away through relative sliding, thereby reducing the obstructive effect and improving the insertion force and smoothness of the instrument in the guiding channel 110. In addition, this structure can also alleviate to a certain extent the deformation problem of the cladding body 300 caused by uneven local stress in the spiral tube 200, enabling the guiding tube 100 to still maintain a relatively stable internal structure in the bent state, and further improving the reliability and adaptability of the guiding structure.

[0048] Therefore, in this embodiment, by setting the third inclined surface 340, the joint stability of the cladding body 300 in the spiral groove 120 is optimized, and the instrument insertion resistance is reduced when the guiding tube 100 is bent, thereby improving the overall performance.

[0049] In some embodiments, the coefficient of thermal expansion of the helical tube 200 < the coefficient of thermal expansion of the cladding body 300 < the coefficient of thermal expansion of the guiding tube 100. Among them, the helical tube 200 is made of a metal material, which usually has a relatively low coefficient of thermal expansion and can provide a stable mechanical support function to a certain extent, avoiding the channel collapse of the guiding tube 100 under bending or compression. The cladding body 300 is made of a material with a coefficient of thermal expansion between that of the helical tube 200 and the guiding tube 100, such as polyethylene or PTFE, etc. These materials not only have good biocompatibility and are suitable for contact with medical fluids in a medical environment, but also can play a buffering role in terms of the coefficient of thermal expansion, thereby reducing the stress concentration problem caused by the expansion mismatch between material layers. The outer guiding tube 100 can be made of materials such as polyurethane or PEBAX, etc. These materials usually have high elasticity and certain wear resistance, and can provide good flexibility and compliance during clinical operations.

[0050] In the multi-layer structure, since the coefficient of thermal expansion of the cladding body 300 is between that of the helical tube 200 and the guiding tube 100, the materials of each layer can expand and contract in a more balanced manner when the temperature changes, thereby reducing the maximum gap between the coefficients of thermal expansion and reducing the stress accumulation that may occur at the interface. This thermal expansion matching method is not only beneficial to maintaining the mechanical bonding between the inner and outer layers, but also can effectively reduce the deformation problems that may occur inside the guiding tube 100 due to thermal expansion and contraction. In addition, the cladding body 300 is filled in the helical groove 120 of the guiding tube 100, so that the parts with larger thermal expansion are axially separated into multiple relatively independent regions, thereby restricting the formation of bulges. Even if a bulge phenomenon occurs in a local area due to temperature changes, it is difficult to expand axially.

[0051] At the same time, a biocompatible adhesive can be coated between the cladding body 300 and the guiding tube 100, which can increase the bonding area on the outer side and both end sides, enhance the bonding strength between the two, and make the overall structure more stable. In addition, since the coefficient of thermal expansion of the helical tube 200 is the smallest and there is a large gap with the polymer material, after the cladding body 300 covers the helical tube 200, it can buffer the stress accumulation caused by uneven material expansion to a certain extent, so that the entire guiding structure can still maintain a stable shape during the temperature change process. Since the helical tube 200 is made of a metal material, its wire structure can provide a limiting effect on the cladding body 300, so that the cladding body 300 will not produce excessive bulges after circumferential expansion. At the same time, since the wire of the helical tube 200 itself is relatively narrow, even if a bulge is formed, it is difficult to expand along the helical direction. In addition, the cladding body 300 presents a "sleeve" - type covering structure to a certain extent, so that it is jointly restricted by the helical tube 200 and the guiding tube 100 when heated and expanded, thereby improving the overall shape - maintaining ability and reducing the risk of channel contraction or structural instability caused by deformation.

[0052] In summary, in this embodiment, by reasonably selecting materials and optimizing the thermal expansion coefficient matching relationship, the guiding structure has good structural stability when the temperature changes. At the same time, combined with the filling design of the cladding body 300, the local bulging phenomenon is suppressed, the mechanical properties and service life of the guiding tube 100 are optimized, thereby improving the overall clinical applicability.

[0053] In some embodiments, the wire surface of the helical tube 200 has a bonding texture, and the bonding texture is closely attached to the inner wall surface of the cladding body 300. Exemplarily, the bonding texture can be obtained by laser etching.

[0054] With such a setting, the wire surface of the helical tube 200 is finely processed to form a bonding texture, and these bonding textures can be processed by means such as laser etching or sandblasting to roughen the wire surface to a certain extent. The setting of the bonding texture can effectively improve the bonding strength between the cladding body 300 and the helical tube 200, enabling the cladding body 300 to adhere more closely to the surface of the helical tube 200, reducing the relative sliding at the interface, and improving the stability of the overall structure. Especially when the guiding tube 100 is bent or subjected to external forces, the cladding body 300 may be displaced due to friction or stress concentration, and the existence of the bonding texture can increase the mechanical biting force between the interfaces to a certain extent, keeping the cladding body 300 stable within the helical groove 120.

[0055] In addition, the morphology of the bonding texture can be optimized according to different application requirements, such as setting micro-grooves, staggered textures or grid-like structures to further enhance the bonding effect. In this way, the adhesion between the cladding body 300 and the helical tube 200 is made more firm, thereby improving the overall durability and performance of the guiding tube 100.

[0056] Exemplarily, the wall thickness of the guiding tube 100 is 0.3 mm to 0.5 mm, the outer diameter is 3 mm to 5 mm; the wall thickness of the helical tube 200 is 0.1 mm to 0.12 mm; the wall thickness of the cladding body 300 is 0.1 mm to 0.15 mm; further, the "wall thickness" described above is the "single-side wall thickness". Exemplarily, the combined wall thickness of the cladding body 300 + the helical tube 200 is 0.21 mm to 0.23 mm.

[0057] In a second aspect, the present application also provides a ureteral sheath, including the guiding structure of the first aspect.

[0058] In a third aspect, the present application also provides a ureteral insertion device, including the guiding structure of the first aspect or the ureteral sheath of the second aspect; or, including the guiding structure of the first aspect or the ureteral sheath of the second aspect, and further including a lens assembly, the lens assembly being disposed at the distal end of the ureteral sheath.

[0059] It should be noted that, in this document, the terms "comprising", "including" or any other variant thereof are intended to cover non-exclusive inclusion, such that a process, method, article or device comprising a series of elements not only includes those elements but also includes other elements not expressly listed, or elements inherent to such process, method, article or device. Without further limitation, an element defined by the phrase "comprising a..." does not exclude the presence of additional identical elements in the process, method, article or device comprising such element.

[0060] In addition, it should be pointed out that the scope of the methods and devices in the embodiments of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in the reverse order according to the functions involved. For example, the described methods may be performed in an order different from that described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

[0061] As described above, the above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of changes or substitutions, which should all be covered within the protection scope of the present invention.

Claims

1. A guiding structure of a ureteral sheath, characterized in that: include: A guide tube (100) having an axially penetrating guide cavity (110) therein, wherein an inner wall of the guide cavity (110) forms a spiral groove (120) extending axially and helically; Spiral tube (200); a cladding body (300) which is closed and coated on the outer peripheral wall of the spiral tube (200) along the extension path of the wire of the spiral tube (200), wherein the cladding body (300) is embedded in the spiral groove (120) along the extension direction of the spiral groove (120); The guide tube (100) and the cladding body (300) are interlocked to form the inner circumferential wall of the guide cavity (110).

2. The guiding structure according to claim 1, characterized in that: A filling limit portion (130) is formed on the guide tube (100) and is located between the spiral segments of the adjacent cladding bodies (300) to limit the spacing between the spiral segments of the adjacent cladding bodies (300).

3. The guiding structure according to claim 1, characterized in that: The cross-sectional shape of the wire of the spiral tube (200) is rectangular, and the cross-sectional shape of the cladding body (300) is circumferentially fitted with the cross-sectional shape of the wire of the spiral tube (200); The spiral tube (200) has two first right-angle portions (210) and two second right-angle portions (220), the two first right-angle portions (210) being located on one side of the spiral tube (200) close to the guide cavity (110), and the two second right-angle portions (220) being located on the other side of the spiral tube (200) away from the guide cavity (110).

4. The guiding structure according to claim 3, characterized in that: The corner outer wall surface of the cladding body (300) corresponding to the second right-angle portion (220) is configured as a rounded surface (310), wherein, along the axial direction of the guide cavity (110), the straight-line distance between the starting point of the rounded surface (310) and the central axis of the guide cavity (110) is greater than or equal to the straight-line distance between the second right-angle portion (220) and the central axis of the guide cavity (110); and / or, the thickness of the cladding body (300) corresponding to the rounded surface (310) is greater than or equal to the thickness of the cladding body (300) corresponding to the surface of the spiral tube (200); and / or, the radius of the rounded surface (310) is less than or equal to the thickness of other parts of the cladding body (300).

5. The guiding structure according to claim 3, characterized in that: The outer wall surface of the corner of the cladding body (300) corresponding to the first right-angle portion (210) is configured as a first inclined surface (320), and the first inclined surface (320) and the spiral groove (120) always maintain a fitting state; Alternatively, the outer wall surface of the cladding body (300) corresponding to the first right-angle portion (210) and the second right-angle portion (220) is configured as a second inclined surface (330), and the second inclined surface (330) is inclined in a direction away from the first right-angle portion (210) or the second right-angle portion (220), and the second inclined surface (330) and the spiral groove (120) are always kept in contact with each other.

6. The guiding structure according to claim 3, characterized in that: The outer corner wall surface of the cladding body (300) corresponding to a first right angle portion (210) close to the proximal end is provided with a third inclined surface (340), and in the axial direction from the proximal end to the distal end of the guide cavity (110), the angle formed by the extension line of the third inclined surface (340) toward the guide cavity (110) and the central axis of the guide cavity (110) is an acute angle.

7. The guiding structure according to any one of claims 1 to 6, characterized in that: The thermal expansion coefficient of the spiral tube (200) is less than the thermal expansion coefficient of the cladding body (300) and less than the thermal expansion coefficient of the guide tube (100).

8. The guiding structure according to any one of claims 1 to 6, characterized in that: The wire surface of the spiral tube (200) has a bonding texture, and the bonding texture is tightly fitted with the inner wall surface of the cladding body (300).

9. A ureteral sheath, characterized in that: It comprises the guiding structure as described in any one of claims 1 to 8.

10. A ureteral insertion device, characterized in that: The guide structure comprises any one of claims 1 to 8 or the ureteral sheath according to claim 9; Or, comprising the guiding structure according to any one of claims 1 to 8 or the ureteral sheath according to claim 9, further comprising a lens assembly, wherein the lens assembly is arranged at the distal end of the ureteral sheath.

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