Guide structure, ureteral sheath and ureteral insertion device

Abstract

The present invention discloses a guide structure, a ureteral sheath, and a ureteral insertion device, belonging to the field of medical device technology. The guide structure includes a guide tube having an axially extending guide cavity, the inner wall of which forms a spiral groove extending axially in a spiral manner; a spiral tube; and a cladding body that is closed and coated on the outer peripheral wall of the spiral tube along the extension path of the wire of the spiral tube, wherein the cladding body is embedded in the spiral groove along the extension direction of the spiral groove; the guide tube and the cladding body are mutually embedded to form the inner peripheral wall of the guide cavity. Compared with the existing technology, the present invention can effectively reduce the occurrence of inner layer bulging, thereby solving the technical problem of ureteral sheaths in related technologies that affects the smoothness of instrument insertion.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular 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. It typically consists of an outer tube, a middle coiled tube (also known as a spring tube), and an inner tube. The device is designed to provide support and create a pathway for endoscopes and other instruments to enter the urinary tract, allowing for smooth insertion of a catheter into the ureter.

[0003] After long-term practice, the inventors found that during surgery, the inner layer of the ureteral sheath often bulges, which 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, so as to solve the technical problem of the ureteral sheath in the related art affecting the smoothness of instrument insertion.

[0005] In order to solve the above problems, the present invention adopts the following technical solutions:

[0006] In the first aspect, the present invention discloses a guide structure of a ureteral sheath, comprising: a guide tube having an axially penetrating guide cavity therein, the inner wall of the guide cavity forming a spiral groove extending axially in a spiral manner; a spiral tube; a cladding body, which is closed and covered on the outer circumferential wall of the spiral tube along the extension path of the wire of the spiral tube, wherein the cladding body is embedded in the spiral groove along the extension direction of the spiral groove; the guide tube and the cladding body are embedded in each other to form the inner circumferential wall of the guide cavity.

[0007] In a second aspect, the present invention further discloses a ureteral sheath comprising the guiding structure described in the first aspect.

[0008] In a third aspect, the present invention further discloses a ureteral insertion device, comprising the guide structure described in the first aspect or the ureteral sheath described in the second aspect;

[0009] Or, it includes the guiding structure described in the first aspect or the ureteral sheath described in the second aspect, and further includes a lens assembly, wherein the lens assembly is arranged at the distal end of the ureteral sheath.

[0010] The technical solution adopted by the present invention can achieve the following beneficial effects:

[0011] The present invention provides a tightly fitting structure between the spiral tube and the cladding body, and adopts 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 due to external forces during use. In addition, the cladding body is provided with different inclined surfaces at the first right angle portion and the second right angle portion, respectively, so that it can keep in contact with the spiral groove, thereby improving its radial fixing effect. When the guide tube is bent by external force, due to the good fitting relationship formed between the cladding body and the spiral tube, delamination, dislocation or bulging will not easily occur, thereby ensuring the overall structural stability of the guide tube. In addition, by rationally designing the gradient relationship of the thermal expansion coefficient, the spiral tube, the cladding body and the guide tube can coordinate expansion or contraction when the temperature changes, avoiding the problem of interface delamination or peeling due to excessive thermal stress differences, further enhancing the structural support capacity of the guide tube, and making it still maintain a stable shape during bending and dynamic operation, meeting the requirements of medical operations;

[0012] In order to reduce material fatigue or damage caused by stress concentration during the use of the guide tube, the present invention introduces a chamfered surface structure at specific parts of the cladding body, especially a rounded transition at the second right angle of the cladding body with a rectangular cross-section, thereby reducing the local stress concentration effect. When the guide tube passes through a narrow or complex cavity, large local stress may be generated due to bending. The presence of the chamfered surface can make the stress more evenly distributed throughout the structure, avoiding a single part from being subjected to excessive force and causing cracks or breakage. In addition, the design of the third inclined surface ensures that when the guide tube is bent and deformed, the protrusion formed by the misalignment of the joint surface between the cladding body and the spiral groove will not form a sharp obstruction, but will smoothly transition along the direction of the guide cavity, so that the medical device will not be affected by obvious 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 enhances the bonding force between the cladding body and the spiral tube, but also prevents the material from interfacial separation due to long-term use or temperature changes to a certain extent, thereby effectively extending the service life of the guide tube and improving its reliability in clinical application.

[0013] The present invention adopts reasonable material selection and bonding methods in the guide tube structure, which makes the bonding between different layers more stable, while improving biocompatibility and ease of use. The cladding body, as the inner layer in contact with the medical fluid, can be made of polyethylene or PTFE material to provide good chemical stability and low friction properties, reducing the sliding resistance of medical devices in the cavity. The outermost layer of the guide tube can be made of polyurethane or PEBAX material, which not only has good flexibility but also can provide a certain support effect, while the spiral tube in the middle layer can be made of metal material to enhance the overall shape retention ability. In addition, the cladding body and the guide tube can be coated with a biocompatible adhesive to increase the bonding area on the outer side and the two end sides, improve the interface strength, and reduce interlayer peeling caused by long-term use or temperature changes. It is worth noting that the bonding texture on the surface of the spiral tube further enhances the fixing effect of the cladding body, so that it can remain stable when subjected to force or temperature changes, and prevent the cladding body from slipping or deforming in the spiral groove. These optimized designs not only improve the durability of the guide tube, but also make it smoother during clinical operation, thereby increasing the success rate of the operation and the safety of the patient. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0015] Figure 1 is a schematic structural diagram of a guide structure of a ureteral sheath in some embodiments of the present application;

[0016] Figure 2 is a partial cross-sectional view of a guide structure of a ureteral sheath according to some embodiments of the present application;

[0017] Figure 3 This is a partial connection cross-section of the guide tube, spiral tube and cladding body in some embodiments of the present application Figure 1 ;

[0018] Figure 4 yes Figure 3 A partial connection cross-sectional view of the spiral tube and the cladding body shown in FIG;

[0019] Figure 5 This is a partial connection cross-section of the guide tube, spiral tube and cladding body in some embodiments of the present application Figure 2 ;

[0020] Figure 6 This is a partial connection cross-section of the guide tube, spiral tube and cladding body in some embodiments of the present application Figure 3 ;

[0021] Figure 7 This is a partial connection cross-section of the guide tube, spiral tube and cladding body in some embodiments of the present application Figure 4 ;

[0022] Figure 8 This is a partial connection cross-section of the guide tube, spiral tube and cladding body in some embodiments of the present application Figure 5 .

[0023] In the picture:

[0024] 100, guide tube; 110, guide cavity; 120, spiral groove; 130, filling limiter; 200, spiral tube; 210, first right-angle portion; 220, second right-angle portion; 300, cladding body; 310, chamfered surface; 320, first inclined surface; 330, second inclined surface; 340, third inclined surface. DETAILED DESCRIPTION

[0025] To make the objectives, technical solutions, and advantages of the present invention more apparent, the technical solutions of the present invention will be described in detail below. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other implementations obtained by those of ordinary skill in the art without inventive effort are within the scope of protection of the present invention.

[0026] The terms "first," "second," and the like in the specification and claims of this application are used to distinguish similar objects, and are not used to describe a specific order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, so that the embodiments of this application can be implemented in an order other than that illustrated or described herein, and that the objects distinguished by "first," "second," and the like are generally of the same type, and do not limit the number of objects; for example, the first object can be one or more. In addition, the term "and / or" in the specification and claims refers to at least one of the connected objects, and the character " / " generally indicates that the objects connected are in an "or" relationship.

[0027] In each embodiment of the present application, "proximal end" and "distal end" refer to the position of each component relative to the user in the use environment, wherein 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".

[0028] In the related art, the ureteral introducer sheath is a medical device widely used in urological surgeries. It is usually composed of an outer tube, an intermediate layer of spiral tube (also known as a spring tube), and an inner tube. The design of this device is to provide a certain amount of support to enable the catheter to be smoothly introduced into the ureter. However, in practice, the inner layer often bulges, especially after long-term use, when the delamination and detachment between the inner and outer tubes become more prominent. After in-depth research, the applicant found that the root cause of the inner tube bulging phenomenon is the delamination and detachment between the outer and inner tubes, which in turn stems from multiple structural defects in the existing design.

[0029] First, the interface between the inner and outer tubes of the ureteral guide sheath is not smooth and continuous. Instead, due to the structural characteristics of the spiral tube in the middle layer, an uneven contact surface is formed. Specifically, the metal-glue interface of the spiral tube exhibits a periodic change pattern, which leads to significant differences in the strength and area of the bonding area. Due to this periodic change, the bonding force of the inner and outer tubes is uneven in different areas, especially when bent or stressed, and it is easy to start to separate from the weak connection points. This separation gradually expands from a small area, eventually causing bulging of the inner tube. Therefore, the structural characteristics of the spiral tube and the periodic changes in the metal-glue interface are the main factors leading to the delamination and separation of the inner and outer tubes.

[0030] Secondly, the spiral tube, which serves as the wire material of the middle layer, has the problem of forward and backward displacement during use. This displacement causes the pitch of the spiral tube to change, which in turn makes the connection quality between the inner and outer tubes unbalanced. The change in pitch not only affects the stability of the connection between the inner and outer tubes, but also applies shear force to the connection surface during the change process. The action of shear force will aggravate the peeling between the inner and outer tubes, thereby further aggravating the occurrence of bulging of the inner tube. Even in the absence of obvious external force, the pitch change itself can cause a slight detachment between the inner and outer tubes, and gradually worsen with the extension of use time, ultimately affecting the overall performance of the ureteral guide sheath.

[0031] Existing technologies fail to effectively address the uneven coupling and pitch variations caused by the spiral tube structure, leading to frequent bulging of the inner tube and delamination of the inner and outer tubes during use. This not only affects the reliability and stability of ureteral guide sheaths during clinical surgery but can also adversely affect the patient's treatment process. Therefore, a new structural design is urgently needed that can effectively prevent or mitigate the delamination of the inner and outer tubes and improve the smoothness of ureteral guide sheath insertion.

[0032] Based on this, the present application provides a guiding structure, a ureteral sheath and a ureteral insertion device.

[0033] The following is combined with Figures 1 to 8, a guide structure, ureteral sheath and ureteral insertion device provided by the present application are described in detail through specific embodiments and their application scenarios.

[0034] First, combining Figure 1 、 Figure 2 as well as Figure 3 The present application provides a guide structure for use in a ureteral sheath, which includes a guide tube 100, a spiral tube 200, and a cladding body 300. The guide tube 100 has an axially penetrating guide cavity 110, and the inner wall of the guide cavity 110 forms a spiral groove 120 extending axially and spirally. At the same time, the cladding body 300 is closed and wrapped around the outer circumferential 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 the guide tube 100 and the cladding body 300 are interlocked to form the inner circumferential wall of the guide cavity 110.

[0035] For example, when making the guide structure, the wire of the spiral tube 200 is first coated with a layer of cladding 300, and then the spiral tube 200 is produced. Thereafter, the guide tube 100 is combined with the spiral tube 200 coated with the cladding 300 by extrusion molding or hot melt technology. In this way, the cladding 300 and the guide tube 100 can jointly provide the inner wall of the guide cavity 110, and the spiral tube 200 coated with the cladding 300 can also be embedded in the spiral groove 120 of the guide tube 100.

[0036] On this basis, the guide structure of the ureteral sheath achieves a more stable interlayer bonding effect by optimizing the covering method of the spiral tube 200 and the structural design of the guide tube 100, thereby reducing the bulging of the inner tube body and interlayer detachment caused by the structural problems of the spiral tube 200 in the prior art.

[0037] First, the inner wall of the guide tube 100 is designed with a spiral groove 120 extending axially in a spiral direction. The spiral groove 120 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 the supporting structure of the intermediate layer, and its wire surface is covered by the cladding body 300. The cladding body 300 is closed and covered on its outer peripheral wall along the wire extension path of the spiral tube 200, and the cladding body 300 is matched with the spiral groove 120 during the manufacturing process and embedded in the spiral groove 120 of the guide tube 100. Such a structural design makes the spiral tube 200 not only simply embedded in the guide tube 100, but also forms a mosaic structure with the cladding body 300. This mosaic method enhances the overall stability of the guide structure to a certain extent, reduces the displacement change problem of the spiral tube 200 due to force or long-term use, and is conducive to maintaining the long-term performance of the ureteral sheath.

[0038] Secondly, the design of the cladding body 300 can effectively improve the bonding quality between the spiral tube 200 and the guide tube 100. As a covering structure, the cladding body 300 can seal the outer circumference of the spiral tube 200 so that the spiral tube 200 is not directly exposed to the inner cavity of the guide tube 100. In this way, the axial continuity of the cladding body 300 can reduce the shearing effect caused by the pitch change of the spiral tube 200 to a certain extent. In other words, when the ureteral sheath is bent or stressed, the wire of the spiral tube 200 is not likely to exert excessive shear force on the bonding part between the guide 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 ensure that even if local fractures occur in the various parts of the spiral tube 200, they can be confined within the covering range of the cladding body 300, thereby maintaining the basic channel shape and avoiding the displacement of the broken part or affecting the passage of instruments in the guide cavity 110.

[0039] In addition, the guiding structure can also improve the inner surface quality of the guiding cavity 110. In the prior art, the inner wall of the ureteral sheath often produces periodic unevenness due to the limitation of the bonding method between the metal material of the spiral tube 200 and the coating rubber layer, which may increase the resistance when the instrument passes through and affect the guiding effect. The present invention completely coats the cladding body 300 on the outer periphery of the spiral tube 200 and forms a matching fit with the spiral groove 120 of the guide tube 100, so that the bonding interface of the inner wall presents a more uniform glue-glue bonding surface rather than a metal-glue bonding surface. This can reduce the unevenness of the interface transition to a certain extent, reduce the risk of delamination due to the difference in bonding strength of different materials, and make the inner wall of the guiding cavity 110 smoother, which is conducive to improving the smoothness of instrument insertion.

[0040] This structural design also has a positive impact during the manufacturing process. Since the spiral tube 200 is wrapped with a layer of cladding 300, its overall anti-axial compression performance is optimized. When the guide tube 100 is combined with the spiral tube 200, the cladding 300 can provide a certain buffering effect, so that the spiral tube 200 maintains a relatively fixed pitch during the assembly process, thereby reducing the quality instability problem caused by pitch changes during the production process. In addition, the presence of the cladding 300 enables the guide tube 100 to distribute stress more evenly to a certain extent, reduce the risk of interlayer delamination caused by local stress concentration, and improve the overall structural stability of the ureteral sheath.

[0041] In summary, by optimizing the sheath structure of spiral tube 200 and the design of guide tube 100, the interlayer bonding is optimized, making the guide structure less susceptible to delamination and detachment during long-term use. This also improves the surface quality of guide channel 110, enhancing smoother instrument insertion and strengthening the stability of the overall structure. This approach, to a certain extent, addresses the interlayer detachment and bulging issues that plague existing ureteral sheath guide structures, providing more reliable technical support for clinical surgery.

[0042] In some embodiments, combined with Figure 2 、 Figure 3 The structural design of the guide tube 100 is further optimized. A filling stopper 130 is formed on the guide tube 100 between the helical segments of adjacent cladding bodies 300. This limits the spacing between the helical segments of adjacent cladding bodies 300 and, to a certain extent, restricts the range of movement of the spiral tube 200 and cladding bodies 300, thereby improving the stability of the overall structure. For example, the filling stopper 130 is actually a portion of the guide tube 100 located between the helical segments of adjacent cladding bodies 300. This portion structurally limits the cladding bodies 300, thereby providing a certain buffering and limiting effect on the axial displacement of the spiral tube 200 and cladding bodies 300.

[0043] During the actual use of the ureteral sheath, since the guide tube 100 may be subjected to bending, torsion and external pressure, the spiral tube 200 and its cladding body 300 may undergo slight displacement in the axial direction. If the range of this displacement is too large, it may cause the pitch of the spiral tube 200 to change unevenly, thereby affecting the overall performance of the guide structure. In this embodiment, the provision of the filling limiter 130 can provide filling support between adjacent spiral segments, so that the axial movement of the spiral tube 200 and the cladding body 300 is constrained to a certain extent, thereby reducing the structural instability problem caused by pitch changes. In addition, the filling limiter 130 can also play a certain buffering role. Under the action of external force, it helps to reduce the stress concentration of the spiral tube 200 and the cladding body 300, reduce the risk of interlayer delamination, and improve the durability of the ureteral sheath during long-term use.

[0044] Furthermore, since the filling stopper 130 is part of the guide tube 100, its material and shape can be optimized based on actual needs. For example, a material with a certain degree of elasticity or flexibility can be selected to provide a limiting effect while still allowing a certain range of elastic deformation, thereby achieving a balance between structural stability and flexibility. This design not only helps maintain the guiding performance of the ureteral sheath, but also reduces the potential for unnecessary displacement of the spiral tube 200 in dynamic environments, improving the smoothness and comfort of instrument insertion.

[0045] In some embodiments, reference Figure 2 、 Figure 3 as well as Figure 4 The cross-sectional shape of the wire material of the spiral tube 200 is designed to be rectangular, and the cross-sectional shape of the cladding body 300 is circumferentially aligned with the cross-sectional shape of the wire material of the spiral tube 200, thereby improving the stability and adaptability of the embedding. Furthermore, the spiral tube 200 has two first right-angled portions 210 and two second right-angled portions 220. The first right-angled portions 210 are located on the side of the spiral tube 200 close to the guide lumen 110, while the second right-angled portions 220 are located on the other side of the spiral tube 200 away from the guide lumen 110.

[0046] After such a configuration, the wire material of the spiral tube 200 with a rectangular cross-section can provide a more stable contact interface during the embedding process compared to the traditional circular or elliptical cross-section. 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, because the rectangular cross-section can provide better support 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.

[0047] At the same time, after being coated with the cladding body 300, the spiral tube 200 with a rectangular cross-section can provide a more regular structural support, making the inner wall of the guide cavity 110 more uniform, reducing the resistance to instrument insertion caused by the uneven surface of the inner wall, and improving the smoothness of the guidance. At the same time, the first right-angled portion 210 of the rectangular structure is located on the side close to the guide cavity 110, making the inner wall of the guide cavity 110 more flat under the support of the spiral tube 200, and the second right-angled 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 not only optimizes structural stability but also improves the overall performance of the ureteral sheath.

[0048] In some embodiments, combined with 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.

[0049] Exemplarily, the straight-line distance between the starting point of the chamfered 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, which means that the transition area of the chamfered surface 310 is relatively outward in geometric distribution, so that the cladding body 300 forms a smoother structural transition here, avoiding local stress concentration caused by right-angle mutation.

[0050] For example, 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, thereby enhancing the structural strength of this part to a certain extent, so that it has better bearing capacity when subjected to stress and reduces the risk of cracking due to fatigue accumulation.

[0051] For example, the radius of the rounded surface 310 is less than or equal to the thickness of other parts of the cladding body 300 , ensuring that effective stress buffering can be provided in this area without excessively increasing the overall wall thickness.

[0052] In practical applications, a ureteral guide sheath must be advanced within the narrow, curved ureter and subjected to pressure from various directions. In such cases, a right-angled design at the corner of the cladding 300 could result in this area becoming a weak link where stress concentration occurs. This can be particularly prone to material fatigue and even microcrack propagation, especially with repeated bending or prolonged use. This embodiment utilizes a rounded surface 310 at the corner of the cladding 300, resulting in a more uniform stress distribution in this area. This helps reduce local stress peaks and improves the structural stability of the guide tube 100 in dynamic environments.

[0053] In addition, the thickness of the cladding body 300 in the area of the rounded corners 310 is set to be greater than or equal to the thickness of the corresponding part of the surface of the spiral tube 200, which further enhances the mechanical strength of this area. Under the action of external force, this area can provide better support, reduce deformation caused by the force on the outer layer, and improve the smoothness of the ureteral sheath during insertion. At the same time, since the radius of the rounded corners 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. Overall, this optimized design can improve the durability of the guide structure while reducing the impact of stress concentration on the integrity of the outer layer structure, thereby improving the stability and reliability of the ureteral guide sheath in clinical use.

[0054] In some optional embodiments, combined with Figure 2 、 Figure 6The outer corner wall surface 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 always maintains a contact state with the spiral groove 120. Through this design, the cladding body 300 is limited in the radial direction, allowing it to be more stably embedded in the spiral groove 120.

[0055] Specifically, the provision of the first bevel 320 enables the cladding body 300 to closely conform to the spiral groove 120 of the guide tube 100 in the radial direction after being inserted into the spiral groove 120. This conforming relationship reduces the possibility of axial or radial displacement of the cladding body 300 during use, thereby improving the stability between the cladding body 300 and the spiral tube 200. Furthermore, compared to a right-angle transition structure, the bevel design of the first bevel 320 helps reduce local stress concentration, making the cladding body 300 less likely to deform or peel under stress, thereby improving the durability and reliability of the guide structure.

[0056] In some other optional embodiments, combined with Figure 2 、 Figure 7 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. 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 always maintains a contact state with the spiral groove 120. This design limits the radial position of the cladding body 300, allowing it to be more stably embedded in the spiral groove 120.

[0057] Specifically, the design of the second bevel 330 provides additional positioning, allowing the cladding body 300 to better axially conform to the spiral groove 120, thereby further enhancing the stability of the cladding body 300 on the surface of the spiral tube 200. Because the second bevel 330 is inclined away from the first right-angled portion 210 or the second right-angled portion 220, this structure can optimize the interlocking relationship between the spiral tube 200 and the guide tube 100 to a certain extent, reducing the micro-displacement of the cladding body 300 caused by stress during long-term use. At the same time, because the second bevel 330 always maintains contact with the spiral groove 120, this contact relationship can provide more stable mechanical support, allowing the cladding body 300 to remain stable even under large bending deformations.

[0058] In some embodiments, Figure 2 、 Figure 8As shown, the outer corner wall surface of the cladding body 300 corresponding to a first right angle portion 210 near the proximal side is configured with a third bevel 340. In the axial direction from the proximal end to the distal end of the guide lumen 110, the angle formed by the extension line of the third bevel 340 toward the guide lumen 110 and the central axis of the guide lumen 110 is an acute angle. For example, the third bevel 340 and the inner wall of the spiral groove 120 always keep in contact. This structural design can effectively improve the impact of the misalignment of the joint surface of the cladding body 300 and the spiral groove 120 on the insertion of the instrument when the guide tube 100 is bent. It is worth noting that in Figure 8 The arrow below indicates the insertion direction of the instrument from the proximal end to the distal end in the guide lumen 110 .

[0059] Specifically, when the guide tube 100 is bent in the human body cavity, the third inclined surface 340 of the cladding body 300 may be slightly deformed due to the local stress concentration of the spiral tube 200. In particular, during the bending process, a slight misalignment may occur between the third inclined surface 340 and the spiral groove 120, thereby forming a protrusion on the inner surface of the guide cavity 110. If these protrusions are directed toward the inside of the guide cavity 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 guide cavity 110 and forms an acute angle with the central axis of the guide cavity 110, when the protrusion is formed, its surface is still smoothly transitioned and roughly consistent with the direction of instrument insertion.

[0060] The advantage of this structure is that even if the cladding body 300 is misaligned in a local area, the protrusion formed by it will not form a significant step-like obstacle, but will gradually rise along the axial direction of the guide cavity 110 to form a smoother transition surface. This smooth structure helps to reduce the resistance caused by the protrusion during the insertion of the instrument, allowing the instrument to pass more smoothly. At the same time, when the distal end of the instrument contacts the protrusion, since the surface of the protrusion is consistent with the insertion direction, the instrument can push it flat or push it away through relative sliding, thereby reducing the obstruction and improving the insertion force and smoothness of the instrument in the guide cavity 110. In addition, this structure can also alleviate the deformation problem of the cladding body 300 caused by the uneven local force on the spiral tube 200 to a certain extent, so that the guide tube 100 can still maintain a relatively stable internal structure in a bent state, further improving the reliability and adaptability of the guide structure.

[0061] Therefore, in this embodiment, by providing the third inclined surface 340 , the bonding stability of the cladding body 300 in the spiral groove 120 is optimized, and the instrument insertion resistance is reduced when the guide tube 100 is bent, thereby improving the overall performance.

[0062] In some embodiments, the thermal expansion coefficient of the spiral tube 200 is less than the thermal expansion coefficient of the cladding body 300, which is less than the thermal expansion coefficient of the guide tube 100. The spiral tube 200 is made of metal material, which usually has a low thermal expansion coefficient and can provide stable mechanical support to a certain extent, thereby preventing the guide tube 100 from collapsing when bent or under pressure. The cladding body 300 is made of a material with a thermal expansion coefficient between that of the spiral tube 200 and the guide tube 100, such as polyethylene or PTFE. These materials not only have good biocompatibility and are suitable for contact with medical fluids in medical environments, but also can play a buffering role in terms of thermal expansion coefficient, thereby reducing stress concentration problems caused by expansion mismatch between material layers. The outer layer guide tube 100 can be made of materials such as polyurethane or PEBAX. These materials usually have high elasticity and certain wear resistance, and can provide good flexibility and compliance in clinical operations.

[0063] In a multi-layer structure, because the thermal expansion coefficient of the cladding 300 is between that of the spiral tube 200 and the guide tube 100, the materials of each layer can expand and contract in a relatively balanced manner when the temperature changes, thereby reducing the maximum difference between the thermal expansion coefficients and reducing the stress accumulation that may occur at the interface. This thermal expansion matching method not only helps maintain the mechanical connection between the inner and outer layers, but also effectively reduces the deformation problems that may occur within the guide tube 100 due to thermal expansion and contraction. In addition, the cladding 300 is filled in the spiral groove 120 of the guide tube 100, so that the area with greater thermal expansion is separated into multiple relatively independent areas along the axial direction, thereby limiting the formation of bulging. Even if bulging occurs in a local area due to temperature changes, it is difficult to expand axially.

[0064] At the same time, a biocompatible adhesive can be applied between the cladding body 300 and the guide tube 100 to increase the bonding area on the outer side and the sides at both ends, thereby enhancing the bonding strength between the two and making the overall structure more stable. In addition, since the thermal expansion coefficient of the spiral tube 200 is the smallest and there is a large gap with the polymer material, after the cladding body 300 covers the spiral tube 200, it can, to a certain extent, buffer the stress accumulation caused by the uneven expansion of the material, so that the entire guide structure can still maintain a stable form during temperature changes. Since the spiral tube 200 is made of metal material, its wire structure can provide a limiting effect on the cladding body 300, so that the cladding body 300 will not produce an excessively large bulge after circumferential expansion. At the same time, since the wire of the spiral tube 200 itself is narrow, even if a bulge is formed, it is difficult to expand in the spiral direction. In addition, the cladding body 300 presents a "sleeve" type covering structure to a certain extent, so that it is constrained by the spiral tube 200 and the guide tube 100 when it expands due to heat, thereby improving the overall shape retention ability and reducing the risk of channel shrinkage or structural instability caused by deformation.

[0065] In summary, this embodiment achieves better structural stability of the guide structure when the temperature changes by rationally selecting materials and optimizing the matching relationship of the thermal expansion coefficients. 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 guide tube 100 are optimized, and the overall clinical applicability is improved.

[0066] In some embodiments, the surface of the wire of the spiral tube 200 has a bonding texture, and the bonding texture is closely attached to the inner wall surface of the cladding body 300. For example, the bonding texture can be obtained by laser etching.

[0067] With such a configuration, the wire surface of the spiral tube 200 is finely processed to form a bonding texture. These bonding textures can be processed by laser etching or sandblasting, etc., so that the surface of the wire produces a certain degree of roughening structure. The setting of the bonding texture can effectively improve the bonding strength between the cladding body 300 and the spiral tube 200, so that the cladding body 300 can be more closely attached to the surface of the spiral tube 200, reduce the relative sliding at the interface, and improve the stability of the overall structure. In particular, when the guide tube 100 is bent or subjected to external force, the cladding body 300 may be displaced due to friction or stress concentration, and the presence of the bonding texture can increase the mechanical bite force between the interfaces to a certain extent, so that the cladding body 300 remains stable in the spiral groove 120.

[0068] Furthermore, the bonding texture can be optimized based on different application requirements, such as by providing micro-grooves, staggered textures, or a grid-like structure to further enhance the bonding effect. This allows for stronger adhesion between the cladding 300 and the spiral tube 200, thereby improving the overall durability and performance of the guide tube 100.

[0069] For example, the wall thickness of the guide tube 100 is 0.3 mm to 0.5 mm, and the outer diameter is 3 mm to 5 mm; the wall thickness of the spiral tube 200 is 0.1 mm to 0.12 mm; and the wall thickness of the cladding body 300 is 0.1 mm to 0.15 mm. Furthermore, the "wall thickness" described above refers to the "single-side wall thickness." For example, the combined wall thickness of the cladding body 300 and the spiral tube 200 is 0.21 mm to 0.23 mm.

[0070] In a second aspect, the present application also provides a ureteral sheath comprising the guiding structure of the first aspect.

[0071] In a third aspect, the present application further provides a ureteral insertion device, comprising the guide structure of the first aspect or the ureteral sheath of the second aspect;

[0072] Alternatively, the guiding structure of the first aspect or the ureteral sheath of the second aspect further includes a lens assembly, wherein the lens assembly is disposed at the distal end of the ureteral sheath.

[0073] It should be noted that, in this document, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or apparatus comprising the element.

[0074] Furthermore, it should be noted that the scope of the methods and apparatuses in the embodiments of the present application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in reverse order depending on the functions involved. For example, the methods described may be performed in an order different from that described, and various steps may be added, omitted, or combined. Furthermore, features described with reference to certain examples may be combined in other examples.

[0075] The above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with this technical field can easily think of changes or replacements within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A guide structure for 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; A spiral tube (200) accommodated in the spiral groove (120); The cladding body (300) spirally extends along the extension path of the wire of the spiral tube (200) and is closed and covered on the outer peripheral wall 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 peripheral wall of the guide cavity (110).

2. The guide structure according to claim 1, characterized in that: A filling limit portion (130) is formed on the guide tube (100) and 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 guide 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), wherein the two first right-angle portions (210) are located on one side of the spiral tube (200) close to the guide cavity (110), and the two second right-angle portions (220) are located on the other side of the spiral tube (200) away from the guide cavity (110).

4. The guide structure according to claim 3, characterized in that: The outer wall surface of the corner 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 chamfered 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 (300) corresponding to the portion of the chamfered surface (310) is greater than or equal to the thickness of the cladding (300) corresponding to the portion of the surface of the spiral tube (200); and / or, the radius of the chamfered surface (310) is less than or equal to the thickness of other portions of the cladding (300).

5. The guide 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 contact 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) always maintain a fit state.

6. The guide 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 guide 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 is less than the thermal expansion coefficient of the guide tube (100).

8. The guide 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 closely fitted to the inner wall surface of the cladding body (300).

9. A ureteral sheath, characterized in that: The invention comprises the guiding structure according to any one of claims 1 to 8.

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

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