Bending-adjustable and pressure-measurable reducing ureter guiding sheath

By designing an adjustable-bend ureteral guide sheath, the problem of stone blockage during lithotripsy was solved, achieving efficient and safe stone removal and simplifying the surgical procedure.

CN224070930UActive Publication Date: 2026-04-03ZHEJIANG YIGAO MEDICAL TECH CO LTD
View PDF 0 Cites 0 Cited by

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Utility models(China)
Current Assignee / Owner
Filing Date
2024-12-03
Publication Date
2026-04-03

AI Technical Summary

Technical Problem

Existing ureteral guiding sheaths are prone to clogging during lithotripsy due to the small gap between the endoscope and the sheath, requiring frequent adjustments to the endoscope position and making the procedure cumbersome.

Method used

Design an adjustable-bend variable-diameter ureteral guide sheath comprising a large-diameter segment and a small-diameter segment, combining rigid and flexible tubing segments. The bending of the flexible tubing segment is controlled by a pull wire to increase the suction channel. Combined with a pressure measurement channel and pressure sensor, the cavity pressure is monitored in real time to optimize surgical procedures.

Benefits of technology

It improves the efficiency of lithotripsy removal, reduces the risk of lithotripsy blockage, simplifies the surgical procedure, and enhances the safety and efficiency of the surgery.

✦ Generated by Eureka AI based on patent content.

Smart Images

  • Figure CN224070930U_ABST
    Figure CN224070930U_ABST
Patent Text Reader

Abstract

The utility model provides a variable-diameter ureter guiding sheath capable of adjusting bending and measuring pressure, the variable-diameter ureter guiding sheath comprises an operation part and an intubation tube suitable for being inserted into a ureter, the intubation tube comprises a large-diameter section and a small-diameter section, the large-diameter section is connected to the near end of the small-diameter section, a large channel is defined in the large-diameter section, and the small-diameter section is connected to the near end of the small-diameter section. A small channel is defined in the small-diameter section, the diameter of the large channel is larger than that of the small channel so as to accelerate fluid passing, and at least part of the small-diameter section is a flexible pipe section. The ureter guiding sheath further comprises at least one pull wire, the pull wire extends in the longitudinal direction and is arranged in the wall of the cannula, the far end of the pull wire is fixedly connected to the head end of the small-diameter section, and the pull wire moves in the longitudinal direction to drive the flexible section to deflect. A pressure measuring channel longitudinally extending from the near side to the far side is defined on the inner side of the cannula wall, a pressure measuring opening for sensing cavity pressure is formed in the far end of the pressure measuring channel, and a pressure sensor is arranged on the pressure measuring channel or any path communicated with the pressure measuring channel.
Need to check novelty before this filing date? Find Prior Art

Description

Technical Field

[0001] This utility model relates to a ureter sheath, specifically a variable diameter ureter guiding sheath. Background Technology

[0002] Currently, natural orifice pyelolithotomy primarily utilizes a ureteral guiding sheath and a flexible ureteroscope. The ureteral guiding sheath is inserted into the urinary tract through the patient's urethra to establish an effective channel for the smooth entry and exit of surgical instruments such as the flexible ureteroscope for the lithotomy procedure. During the procedure, current techniques involve introducing water into the working channel of the endoscope and draining it from the gap between the endoscope and the sheath, creating a negative pressure suction to promptly remove the laser-dislodged stone fragments. However, due to the small gap between the endoscope and the sheath, stone fragments can easily become lodged between them. Therefore, the endoscope needs to be withdrawn from the sheath to remove the fragments promptly. This requires repeated insertion and withdrawal of the endoscope during the procedure, making the entire process quite cumbersome. Utility Model Content

[0003] This invention provides an adjustable-diameter ureteral guide sheath, comprising an operating part and a cannula suitable for insertion into the ureter. The operating part is connected to the proximal end of the cannula, and the cannula defines a central channel extending from the proximal end to the distal end. The operating part defines an inlet communicating with the central channel of the cannula, and the inlet is provided with a sealing valve to allow instruments to pass through the central channel in a sealed manner. The operating part has a negative pressure connector communicating with the central channel. The cannula includes a large-diameter section and a small-diameter section, with the large-diameter section connected to the proximal end of the small-diameter section. The large-diameter section defines a large channel, and the small-diameter section defines a small channel. The inner portion of the ureteral guide sheath defines a small channel, the diameter of which is larger than that of the small channel to accelerate fluid flow. At least a portion of the small-diameter section is a flexible tube segment. The ureteral guide sheath also includes at least one pull wire, which extends longitudinally and is located within the cannula wall. The distal end of the pull wire is fixedly connected to the head end of the small-diameter section. When the pull wire moves longitudinally relative to the main body section, it causes the flexible tube segment to deflect. The inner side of the cannula wall defines a pressure measuring channel extending longitudinally from the proximal side to the distal side. The distal end of the pressure measuring channel has a pressure measuring port for sensing cavity pressure. A pressure sensor is provided on the pressure measuring channel or any path connected to it.

[0004] In some embodiments, a pressure sensor suitable for sensing cavity pressure is provided at the distal end of the pressure measuring channel, and the sensor outputs a signal through a signal line penetrating the pipe wall.

[0005] In some embodiments, the operating unit is provided with a pressure measuring cavity communicating with the pressure measuring channel, and the pressure sensor is disposed in the operating unit to sense the pressure in the pressure measuring cavity.

[0006] In some embodiments, the large-diameter section of the cannula is a rigid section, and the flexible section is flexible enough to bend compared to the rigid section.

[0007] In some embodiments, a pull wire outer tube is fixed inside the wall of the cannula, the pull wire extends longitudinally inside the pull wire outer tube, and the proximal end of the pull wire is controlled by an operating unit.

[0008] In some embodiments, the outer diameter of the larger diameter segment is greater than the outer diameter of the smaller diameter segment, and the larger diameter segment is configured to support the curved passage within the ureter so that it deforms from a curved shape to a straight shape.

[0009] In some implementations, the large-diameter section is connected to or integrally formed with the small-diameter section.

[0010] In some embodiments, the large-diameter section is a rigid pipe section, and the small-diameter section includes a flexible pipe section and a transition section, with the transition section connecting the rigid pipe section and the flexible pipe section in the middle.

[0011] In some embodiments, the large-diameter section is a rigid pipe section, the small-diameter section includes a flexible pipe section and a head end, the head end has a higher rigidity than the flexible pipe section, and the distal end of the pull wire is fixed to the head end.

[0012] In some embodiments, the cannula is at least a multi-layered tube in its small diameter section, and the tube wall of the multi-layered tube includes an inner tube, a support layer and an outer tube from the inside to the outside, with the support layer disposed between the inner tube and the outer tube; preferably, the support layer is an elastic layer, preferably a spring tube.

[0013] In some embodiments, a fixing member is provided at the head end, and the pull tube is located inside the wall of the insertion tube.

[0014] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0015] Figure 1 A schematic diagram of the structure of a variable-diameter ureteral guide sheath (with dilator) provided for an embodiment;

[0016] Figure 2 A cross-sectional view of the structure of the variable-diameter ureteral guide sheath provided in the embodiment;

[0017] Figure 3 A schematic diagram of the structure of the variable-diameter ureteral guide sheath and endoscope assembly provided in the embodiment;

[0018] Figure 4 for Figure 3A magnified view of a portion of the image;

[0019] Figure 5 A schematic diagram of the structure of the variable-diameter ureteral guide sheath provided in the embodiment;

[0020] Figure 6 A schematic diagram of a flexible variable-diameter ureteral guide sheath provided for an embodiment;

[0021] Figure 7 for Figure 2 A magnified view of a portion of the image;

[0022] Figure 8 This is a schematic diagram of the urethra.

[0023] Figure 9 The existing design provides a schematic diagram of the ureteral guide sheath entering the renal pelvis;

[0024] Figure 10 A schematic diagram showing the state of the variable-diameter ureteral guide sheath entering the renal pelvis as provided in the embodiment;

[0025] Figure 11 and Figure 12 A schematic diagram of the structure of an adjustable-bend ureteral guide sheath provided in one embodiment;

[0026] Figure 13 and Figure 14 A schematic diagram of the adjustable-bend-diameter ureteral guide sheath provided for another embodiment;

[0027] Figure 15 A cross-sectional view of a pressure-measurable variable-diameter ureteral guide sheath structure provided for another embodiment;

[0028] Figure 16 for Figure 15 A partial schematic diagram; Detailed Implementation

[0029] The present invention or its technical solutions will be further described in detail below through specific embodiments and in conjunction with the accompanying drawings;

[0030] In the description of this invention, "proximal" and "proximal side" refer to the end of the medical device that is closer to the doctor during normal operation, while "distal" and "distal side" usually refer to the end that first enters the patient's body.

[0031] In the description of this invention, it should be noted that, unless otherwise specified and limited, the terms "installation" and "connection" should be interpreted broadly. For example, they can refer to mechanical or electrical connections, or internal connections between two components. They can be direct connections or indirect connections through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0032] Please see Figures 1-4 The existing design of the ureteral guide sheath includes an operating part 1 and a cannula 2 suitable for insertion into the ureter. The operating part 1 is connected to the proximal end of the cannula 2. The cannula 2 defines a central channel 100 extending from the proximal end to the distal end. The operating part 1 defines an inlet 12 communicating with the central channel 100 of the cannula 2 for instrument entry. A sealing valve 121 is provided at the inlet 12 for instruments such as an endoscope 3 to pass through in a sealed manner. The operating part 1 has a negative pressure connector 11 communicating with the central channel. During pyelonephrosis, the guide sheath is inserted into the ureter through a dilator 5, and external instruments such as an endoscope 3 pass through the cannula 2. The central channel reaches the target position. The negative pressure connector 11 is connected to the negative pressure suction device. The laser or other instruments enter the cavity through the endoscope 3 to perform lithotripsy or cutting of stones or other tissues in the cavity. The irrigation device injects physiological saline into the cavity through the endoscope channel. The gap between the endoscope 3 and the central channel 100 forms a suction channel. The negative pressure suction device draws the liquid containing the stones out of the body through the suction channel. In this way, the lithotripsy and stone removal work is completed. The distal end of the cannula needs to be able to reach the renal pelvis and bend freely to be aligned with the target (stone fragments or tissues). Therefore, there are strict requirements on its size.

[0033] This embodiment provides a variable-diameter ureteral guiding sheath. The cannula includes a large-diameter segment 22 and a small-diameter segment 21, which are connected. The large-diameter segment 22 is connected to the proximal end of the small-diameter segment 21. The interior of the large-diameter segment 22 defines a large channel 220, and the interior of the small-diameter segment 21 defines a small channel 210. The diameter of the large channel 220 is larger than the diameter of the small channel 210 to accelerate fluid passage. Thus, the small-diameter segment 21 is suitable for entering the target position of the renal pelvis and can move freely, while the large channel defined by the large-diameter segment 22 increases the radial dimension of the suction channel, facilitating the rapid passage of stones or other tissues, accelerating their dislodgement and outflow, and greatly improving efficiency.

[0034] In a further embodiment of this utility model, the distal segment 211 of the small-diameter section is a flexible pipe segment; see below. Figure 6 After the endoscope 3 (flexible endoscope) enters the central channel, its flexible tube segment 211 bends flexibly with the curved part of the flexible endoscope, bending straight to the renal calyx. This design is crucial for lithotripsy and stone removal in the lower calyx and for improving the efficiency of flexible endoscope stone removal.

[0035] Furthermore, the large-diameter section 22 of the cannula is a rigid segment, while the distal section of the small-diameter section 21 is a flexible segment, allowing it to bend. This flexible segment can be actively controlled by the user, the physician. For example, a pull wire can be placed on the wall of the cannula 2 to actively control the bending of the flexible segment relative to the rigid segment. The movement of the pull wire can also be controlled manually or intelligently to control the bending angle or repositioning of the flexible segment. In addition, the proximal side of the cannula uses a rigid component to facilitate the physician's insertion of the guide sheath into the cavity, while protecting the sheath from deformation.

[0036] In some examples, please refer to Figure 5 The large-diameter section is a rigid pipe section, and the small-diameter section includes a flexible pipe section 211 and a transition section 212. The transition section 212 connects the rigid pipe section and the flexible pipe section, and its rigidity is between that of the rigid pipe section and the flexible pipe section. In other examples, the large-diameter section is a rigid pipe section, and the entire small-diameter section is a flexible pipe section.

[0037] Optionally, both the large-diameter section 22 and the small-diameter section 21 can be multi-layer pipes; please refer to [link / reference]. Figure 7 The multi-layer tube, from its inner to outer side, comprises an inner tube 201, a support layer 202, and an outer tube 203. The support layer 202 is disposed between the inner tube 201 and the outer tube 203, thus facilitating the bending of the small-diameter section. For example, the inner tube 201 is often an externally etched PTFE tube, ensuring both effective connection between the inner tube 201 and the outer tube 203 and a smooth inner wall for easy instrument passage. For instance, both the large-diameter section 22 and the small-diameter section 21 are multi-layer tubes, forming an integrated structure. In this way, the support layer 202 increases in size synchronously with the increase in the outer diameter of the large-diameter section 22, resulting in a stable, reliable, and aesthetically pleasing integrated structure. In other examples, the large-diameter section 22 and the small-diameter section 21 are separate structures. The multi-layered tube ends at the diameter change point. The large-diameter section 22 adopts an independent structure, such as a pure plastic tube or a metal tube (stainless steel tube, nickel-titanium tube), and is connected by rheological bonding or adhesive bonding. The small-diameter section 21 is generally made of Pebax material, while the large-diameter section 22 can be made of Pebax material or other materials, or the same material or different materials. The large-diameter section can be distinguished by different colors or transparency, making it easier for doctors to identify the positions of the large-diameter section and the small-diameter section without having to retract the endoscope.

[0038] In this embodiment, the outer diameter of the large-diameter segment 22 is larger than that of the small-diameter segment 21, meaning that both the inner and outer diameters of the large-diameter segment 22 are larger. The large-diameter segment 22 is configured to support the curved channel within the ureter, allowing it to straighten from a curved shape. Specifically, the outer diameter and rigidity of the large-diameter segment 22 are designed to support the cavity, thus strengthening the curvature and allowing for straightening deformation. Its length is also longer than the curved cavity to achieve straightening deformation. Compared to existing ureteral sheaths, where stones need to bypass the curved cavity to be expelled, the inherent size limitations of the suction channel make it easy for stones to become stuck at the bend. This invention deforms the curved cavity during surgery and, in conjunction with the enlargement of the suction channel, accelerates stone expulsion efficiency and eliminates the risk of stones easily becoming stuck at the bend. For example, please refer to [link to relevant documentation]. Figure 8 The bladder (a) is bordered by the urethra (b) posterior to it and the ureter (d) anterior to it. The renal pelvis (e) is located anterior to the ureter. The urethra has two curves: the prepubic curve (b1) and the subpubic curve (b2). Please refer to [link / reference]. Figure 9 Existing ureteral guiding sheaths, after entering the ureter, have a gap-like design, making it extremely easy for stones or other tissues to become lodged at the bend, causing suction blockage. Please refer to... Figure 10 The large-diameter section 22 of the variable-diameter ureteral guiding sheath provided in this embodiment is a rigid tube section. It does not deform in the two physiological bends of the male urethra, and directly straightens the two physiological bends. In this way, the flow process of the target object, such as gravel, which originally had to go through two large bend angles to flow out can now be reduced by reducing the flow process of two bend angles, and the occurrence of gravel getting stuck at the bend is eliminated.

[0039] In this embodiment, the cannula 2 is positioned at the junction of the large diameter section 22 and the small diameter section 21 to enter the bladder without contacting the ureteral orifice. Thus, the variable diameter design satisfies the requirement for the small diameter section to enter the bladder while also allowing for the expulsion of stones.

[0040] The cannula 2 has a proximal end and a distal end. In some embodiments of this invention, the tip 2111 of the ureteral guide sheath is adjustable. As mentioned earlier, this adjustment can be achieved by the bending portion of the endoscope causing the tip 2111 to deflect, or by the deflectability of the ureteral sheath itself. In some embodiments, please refer to... Figures 11-12 A pull wire 30 is installed inside the wall of the insertion tube 2. The pull wire 30 is slidably pulled inside the outer tube 31. The far end of the pull wire 30 is fixed to the head end of the small diameter section 21. The operating unit 1 controls and drives the pull wire 30 to move longitudinally relative to the main body section, thereby causing the head end to deflect by the flexible tube section.

[0041] In other embodiments, please refer to Figures 13-14Two pull wires 30 are symmetrically arranged inside the cannula wall. Pulling the pull wires 30 causes the flexible tube section to deflect upward or downward.

[0042] Understandably, it is also possible to install more than two guy wires.

[0043] Please refer to it again. Figure 13 To achieve the deflection of the pull wire 30, the distal end of the pull wire 30 is fixed to the head end 2111 of the small-diameter section. The head end 2111 is equipped with a fixing member 6 to facilitate the bending and deflection of the flexible tube section. It can be understood that the flexible tube section, as a bending section, has a lower stiffness than the tube section and the head end nearby. The bending of the flexible tube section causes the head end 2111 to deflect. Furthermore, the pull wire tube 31 is disposed between the inner tube 201 and the support layer 202, or it can be disposed in other layers.

[0044] Optionally, the proximal end of the pull wire 30 can be pulled manually or mechanically. In some examples, the operating part 1 is provided with a power transmission component, and the proximal end of the pull wire 30 is located on the power transmission component. The power transmission component is adapted to be connected to a motor, and each pull wire is driven by the power transmission machine to slide longitudinally. Exemplarily, the power transmission component is a turntable, and the proximal end of the pull wire 30 is wound on the turntable. The counterclockwise or clockwise rotation of the turntable drives the pull wire to move longitudinally to the proximal or distal side. The turntable is connected to a corresponding mating part on the equipment, and the power of the motor on the equipment is transmitted to the turntable, and then transmitted to the flexible pipe section through the pull wire 30.

[0045] Furthermore, such as Figure 15 and Figure 16 As shown, the inner side of the cannula 2 defines a pressure measuring channel 61 extending longitudinally from the proximal side to the distal side. The distal end of the pressure measuring channel has a pressure measuring port for sensing the pressure of the cavity. The pressure measuring channel is equipped with a pressure sensor 62 to detect the pressure inside the cavity. The operating part 1 is equipped with a pressure measuring interface 60 that communicates with the pressure measuring channel 61 to facilitate signal transmission.

[0046] In this embodiment, the pressure sensor 62 is an optical fiber sensor, which is installed through the pressure measurement channel and connected to the pressure measurement device through the pressure measurement interface. In other embodiments, please refer to... Figure 15 and Figure 16 The pressure sensor 65 can be installed inside the operating part 1 and can detect the pressure of the pressure measuring channel 61; more preferably, the operating part is also provided with a control button 66 to control the infusion and aspiration states, and the negative pressure connector is installed at the lower part of the operating part and is perpendicular to the suction channel to facilitate drainage.

[0047] In this embodiment, the entire cannula is a multi-layered tube structure, and the pressure measurement channel is composed of a sensor outer tube, which can be made of PI or PTFE material. The sensor is installed between the support layer and the outer tube, ensuring a stable and reliable structure. Correspondingly, a pressure measurement port 63 corresponding to the pressure measurement channel is provided on the outer wall of the cannula 2. This embodiment innovatively combines a variable-diameter ureteral guiding sheath with pressure measurement functionality, increasing stone outflow efficiency without affecting the performance of the original sheath, while simultaneously monitoring the intrarenal pelvis pressure in real time, thus achieving safe and reliable surgical procedures.

[0048] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0049] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. An adjustable and pressure-measuring variable-diameter ureteral guide sheath, comprising an operating part and a cannula adapted for insertion into the ureter, the operating part being connected to the proximal end of the cannula, the cannula defining a central channel extending from the proximal end to the distal end, the operating part defining an inlet communicating with the central channel of the cannula, the inlet being provided with a sealing valve for instruments to pass through and enter the central channel in a sealed manner, the operating part having a negative pressure connector communicating with the central channel, characterized in that... The cannula includes a large diameter section and a small diameter section, the large diameter section is connected to the proximal end of the small diameter section, the interior of the large diameter section defines a large channel, the interior of the small diameter section defines a small channel, the diameter of the large channel is larger than the diameter of the small channel to accelerate fluid passing, the small diameter section is at least partially a flexible tube section; the ureter guide sheath further includes at least one pull wire, the pull wire extends longitudinally and is arranged in the wall of the cannula, the distal end of the pull wire is fixedly connected to the head end of the small diameter section, the longitudinal movement of the pull wire drives the flexible tube section to deflect; the interior of the wall of the cannula defines a pressure measuring channel extending longitudinally from the proximal side to the distal side, the distal end of the pressure measuring channel has a pressure measuring port for sensing the pressure of the cavity, a pressure sensor is arranged on the pressure measuring channel or any path in communication therewith.

2. The variable diameter ureteral guide sheath of claim 1, wherein, The distal end of the pressure measuring channel is provided with a pressure sensor suitable for sensing the pressure of the cavity, the sensor outputs a signal through a signal line penetrating the wall of the tube.

3. The variable diameter ureteral guide sheath of claim 1, wherein, The operating part is provided with a pressure measuring tube cavity in communication with the pressure measuring channel, and the pressure sensor is arranged in the operating part for sensing the pressure of the pressure measuring tube cavity.

4. The variable diameter ureteral guide sheath of claim 1, wherein, The large diameter section of the cannula is a hard tube section, and the flexible tube section is such that the flexible tube section is bendable compared to the hard tube section.

5. The variable diameter ureteral guide sheath of claim 1, wherein, A pull wire outer tube is fixedly arranged in the interior of the wall of the cannula, the pull wire longitudinally extends in the pull wire outer tube, and the proximal end of the pull wire is controlled by the operating part.

6. The variable diameter ureteral guide sheath of claim 3, wherein, The outer diameter of the large diameter section is larger than the outer diameter of the small diameter section, and the large diameter section is configured to support the curved channel in the ureter to deform from a curved shape to a straight shape.

7. The variable diameter ureteral guide sheath of claim 2, wherein, The large diameter section and the small diameter section are connected or integrally formed.

8. The variable diameter ureteral guide sheath of claim 1, wherein, The large diameter section is a hard tube section, the small diameter section includes a flexible tube section and a transition section, and the transition section is connected between the hard tube section and the flexible tube section.

9. The variable diameter ureteral guide sheath of claim 1, wherein, The large diameter section is a hard tube section, the small diameter section includes a flexible tube section and a head end, the hardness of the head end is greater than the hardness of the flexible tube section, and the distal end of the pull wire is fixed to the head end.

10. The variable diameter ureteral guide sheath of claim 9, wherein, The head end is provided with a fixing member, and the pull wire tube is arranged in the wall of the cannula.

11. The variable diameter ureteral guide sheath of claim 1, wherein, At least the small diameter section of the cannula is a multilayer tube, the wall of the multilayer tube includes an inner layer tube, a support layer and an outer layer tube from the inside to the outside in sequence, and the support layer is arranged between the inner layer tube and the outer layer tube.

12. The variable diameter ureteral guide sheath of claim 11, wherein, The support layer is an elastic layer.

13. The variable diameter ureteral guide sheath of claim 11, wherein, The support layer is a spring tube.