Tube sheath and endoscope system

Abstract

The invention relates to the technical field of endoscopes, and particularly discloses a tube sheath and an endoscope system.The tube sheath comprises a tube sheath body, the tube sheath body is provided with an axially-through first channel, and the far end of the tube sheath body is provided with a second channel communicating with the first channel and penetrating through the tube sheath body in the radial direction; according to the scheme, in the insertion stage of the pipe sheath body, an endoscope can clearly see the tissue structure and obstacles in front through the first channel, the visibility of the insertion process is improved, the risk of blind insertion is reduced, after the pipe sheath body reaches the target position, the endoscope can be retreated to enable the front end of the endoscope to be located at the communicating position of the first channel and the second channel, and therefore the endoscope can be conveniently inserted into the pipe sheath body. The endoscope is operated to enable the front end of the endoscope to be bent and extend into the second channel, based on the guiding effect of the second channel on the front end of the endoscope, it is ensured that the endoscope can accurately enter the common bile duct from the side direction of the duct sheath body, and therefore the situation that the endoscope depends on a duodenoscope when extending into the common bile duct is avoided, and cost is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of endoscopes, and in particular to a sheath and an endoscope system. Background Art

[0002] Diseases of the bile duct and pancreatic system, such as bile duct stones, stenosis and tumors, are common clinical diseases. With the development of endoscopic technology, the combined use of duodenoscopes and choledochoscopes has become the core solution for minimally invasive treatment. After the duodenoscope is intubated, its position in the ampulla is kept stable, and the choledochoscope is slowly sent into the common bile duct through the working channel of the duodenoscope until it reaches the target position (such as the intrahepatic bile duct branches) for surgical operations such as laser lithotripsy and biopsy sampling.

[0003] However, although the current clinical solution of using a duodenoscope in combination with a choledochoscope can achieve minimally invasive biliary diagnosis and treatment, it still faces the significant disadvantage of high equipment and operating costs. Therefore, providing a solution that can be used in conjunction with a choledochoscope and significantly reduce the cost of diagnosis and treatment is a technical problem that needs to be urgently solved by technical personnel in this field. Summary of the invention

[0004] The invention discloses a tube sheath and an endoscope system to solve the above technical problems existing in the related technology.

[0005] In order to solve the above problems, the present invention adopts the following technical solutions: In a first aspect, the present application provides a sheath, which includes a sheath body, the sheath body having a first channel extending axially therethrough, the sheath body also being provided with a second channel, the second channel being distributed at the distal end of the sheath body, one end of the second channel being connected to the first channel, and the other end of the second channel radially extending through the sheath body.

[0006] Further, the second channel extends linearly, and the extension direction of the second channel has a first angle with the first direction, the first angle is less than or equal to 90°, and the first direction is the extension direction of the sheath body from its proximal end to its distal end; or, the second channel extends in an arc shape, and the tangent direction at the distal end of the second channel has a second angle with the first direction, the second angle is less than 90°, and the first direction is the extension direction of the sheath body from its proximal end to its distal end.

[0007] Furthermore, the sheath body has an arc-shaped transition at the connection between the first channel and the second channel.

[0008] Furthermore, along the radial direction of the sheath body, the sheath body has a first part and a second part distributed on both sides of the first channel, the second channel is arranged in the second part, and at the connection point between the first channel and the second channel, the thickness of the second part is greater than the thickness of the first part.

[0009] Further, the thickness of the second portion at the connection point between the first channel and the second channel is greater than the thickness of the second portion distributed at a proximal end of the connection point.

[0010] Furthermore, the sheath also includes a guide tube, and the distal end of the guide tube has a curved section.

[0011] Optionally, the curved section is pre-bent, and when the curved section is located at a connecting point between the first channel and the second channel, the curved section bends toward the second channel to penetrate into the second channel.

[0012] Optionally, the curved section is connected to a traction member, and the traction member is configured to pull the curved section to bend, so that the curved section is located in the first channel or extends into the second channel.

[0013] Furthermore, along the first direction, the diameter of the guide tube gradually decreases, and the first direction is the extension direction of the sheath body from its proximal end to its distal end.

[0014] Furthermore, the sheath also includes a sheath seat, which includes a base and a movable part slidably arranged on the base, the proximal end of the sheath body is connected to the base, and the guide tube is connected to the movable part.

[0015] Furthermore, a knob is provided on the movable portion, and the knob is transmission-connected to the bending section through the traction member to control the bending of the bending section.

[0016] In a second aspect, the present application further provides an endoscope system, comprising an endoscope and the aforementioned sheath, wherein an insertion portion of the endoscope is inserted into the first channel or the second channel.

[0017] The technical solution adopted by the present invention can achieve the following beneficial effects: In the sheath and endoscope system of the present application, the endoscope can be pre-placed in the first channel, and the front end of the endoscope exceeds the connection point between the first channel and the second channel. When the sheath body is inserted into the human body cavity, the bending posture of the endoscope is consistent with the bending posture of the sheath body. The endoscope can use the first channel to clearly see the tissue structure and obstacles in front of the human body cavity, thereby improving the visibility of the sheath body during the insertion process and reducing the risk of blind insertion. After the sheath body reaches the target position, the endoscope can be retracted so that its front end is located at the connection point between the first channel and the second channel, and then the endoscope is operated to make its front end probe into the second channel. Based on the guiding effect of the second channel on the front end of the endoscope, it is ensured that the endoscope can accurately enter the common bile duct from the side of the sheath body. At the same time, the sheath body can also provide stable support performance for the endoscope, which can effectively avoid the influence of frequent peristalsis of the intestinal cavity on the endoscope. This method avoids the dependence of the endoscope on the duodenoscope when probing into the common bile duct, while ensuring the safety and accuracy of operation, greatly reducing the application cost of the endoscope system. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. 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 creative work.

[0019] Figure 1 is a schematic diagram of the structure of the sheath of an embodiment of the present application; Figure 2 It is one of the cross-sectional schematic diagrams of the sheath of the embodiment of the present application; Figure 3 This is the second schematic cross-sectional view of the sheath of the embodiment of the present application; Figure 4 yes Figure 3 A local enlarged schematic diagram of the middle A; Figure 5 This is the third schematic cross-sectional view of the sheath of the embodiment of the present application; Figure 6 yes Figure 5 A partial enlarged schematic diagram of point B in the middle; Figure 7 This is the fourth schematic cross-sectional view of the sheath of the embodiment of the present application; Figure 8 yes Figure 7 A partial enlarged schematic diagram of point C in the middle; Fig. 9 It is a schematic diagram of the structure of the endoscope system of an embodiment of the present application.

[0020] In the figure: 100, sheath body; 101, first part; 102, second part; 110, first channel; 120, second channel; 200, guide tube; 210, bending section; 300, sheath seat; 310, base; 320, movable part; 330, knob; 400, choledochoscope. DETAILED DESCRIPTION

[0021] To make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described in detail below. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other implementation methods obtained by ordinary technicians in this field without creative work belong to the scope of protection of the present invention.

[0022] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0023] During the diagnosis and treatment of bile and pancreatic diseases, the choledochal sub-scope is usually used in conjunction with the duodenoscope to form a mother-and-daughter scope system. After the duodenoscope completes the intubation, it maintains its stability in the ampulla position and slowly inserts the choledochal sub-scope into the common bile duct through the working channel of the duodenoscope until it reaches the target position. In other words, the duodenoscope is a "portal tool" for the treatment of bile and pancreatic diseases. It can locate the ampulla and interventional operations of the main bile duct. At the same time, the duodenoscope can also provide stable channel support for the choledochal sub-scope, avoiding the choledochal sub-scope from falling out due to frequent peristalsis of the duodenoscope, and eliminating the influence of intestinal movement on the operation of the choledochal sub-scope.

[0024] However, since the duodenoscope integrates a side-view optical system, a forceps elevator mechanical structure, and a multi-channel design, the equipment cost is relatively high. In addition, the complex internal structure of the duodenoscope (including the forceps elevator cavity, biopsy channel, etc.) further increases the maintenance and application cost of the duodenoscope. Repeated high-temperature and high-pressure disinfection during use causes the sealing of the duodenoscope to decrease, which has a serious impact on the service life of the duodenoscope.

[0025] Based on the above situation, the present application embodiment discloses a sheath and an endoscope system. Figures 1 to 9, the sheath and endoscope system provided in the embodiments of the present application are described in detail through specific embodiments and their application scenarios.

[0026] See also Figure 1 and Figure 2 The embodiment of the present application discloses a sheath, which can be used in combination with an endoscope (such as a choledochoscope) for the diagnosis and treatment of diseases of the biliary and pancreatic system. Specifically, in the embodiment of the present application, the disclosed sheath includes a sheath body 100, which is a tubular structure having a first channel 110 extending axially therethrough, and the sheath body 100 is further provided with a second channel 120 at its distal end, one end of the second channel 120 being connected to the first channel 110, and the other end of the second channel 120 radially passes through the annular wall of the sheath body 100.

[0027] Based on this technical solution, when the sheath of the embodiment of the present application is used in conjunction with an endoscope (such as a choledochoscope) to diagnose and treat diseases of the biliary and pancreatic system, the insertion portion of the choledochoscope can be pre-placed in the first channel 110, and the distal end of the insertion portion exceeds the connection between the first channel 110 and the second channel 120. During the process of inserting the sheath body 100 into the human body cavity, the choledochoscope can use the first channel 110 to clearly see the tissue structure and obstacles in front of the human body cavity, thereby improving the visibility of the sheath body 100 during the insertion process, assisting the operator in pushing the sheath body 100 to the target position, and reducing The risk of blind insertion is reduced; after the sheath body 100 reaches the target position, the endoscope can be retracted so that the distal end of the insertion part is retracted to the connecting point of the first channel 110 and the second channel 120, and then the choledochoscope is operated to make the distal end of the insertion part probe into the second channel 120. Based on the guiding effect of the second channel 120 on the distal end of the choledochoscope, it is ensured that the insertion part of the choledochoscope can accurately enter the common bile duct from the side of the sheath body 100, and the sheath body 100 can also provide stable support performance for the choledochoscope, which can effectively avoid the risk of the choledochoscope falling out due to frequent peristalsis of the intestinal cavity. That is to say, the embodiment of the present application provides a first channel 110 and a second channel 120 that are connected on the sheath body 100, so that the biliary sub-scope can switch between forward view and side view, and when the biliary sub-scope probes into the common bile duct through the second channel 120 with side view, the sheath body 100 can provide stable support performance for the biliary sub-scope. This method avoids the reliance of the biliary sub-scope on the duodenoscope when probing into the common bile duct, that is, avoids the use of the duodenoscope, and greatly reduces the diagnosis and treatment costs of biliary and pancreatic diseases while ensuring operational safety and accuracy.

[0028] It can be understood that in the embodiment of the present application, when the choledochoscope is inserted into the common bile duct through the second channel 120, the sheath body 100 can provide stable support for the choledochoscope, and therefore, it is necessary to keep the sheath body 100 relatively fixed after reaching the target position. Exemplarily, the operator can hold the rear end of the sheath to keep the sheath body 100 relatively fixed after reaching the target position; or, before the choledochoscope is withdrawn, the distal end of the sheath body 100 can be bent to form a C-shaped or J-shaped structure through the bending action of the choledochoscope, thereby forming a geometric bite with the inner wall of the intestine, so that the sheath body 100 remains relatively fixed after reaching the target position, thereby providing stable support for the choledochoscope.

[0029] In some embodiments of the present application, the sheath body 100 is further provided with a transparent glass slide at the distal end of the first channel 110. When the distal end of the choledochal sub-scope is located in the first channel 110, the choledochal sub-scope can achieve forward vision through the transparent glass slide, and the transparent glass slide can ensure the sealing of the first channel 110, thereby preventing bile or blood from flowing back into the interior of the sheath, thereby effectively avoiding the risk of cross infection.

[0030] As can be seen from the above, the choledochoscope needs to pass through the second channel 120 to probe into the common bile duct. Therefore, in the present application, the second channel 120 is non-closed. In a preferred embodiment, the sheath body 100 is provided with a valve valve in the second channel 120. The valve valve can play a certain physical shielding role to prevent bile and other tissue fluids or blood from flowing into the interior of the sheath body 100. When the bile duct itself probes into the second channel 120, it can pass through the valve valve and smoothly enter the common bile duct.

[0031] In some embodiments of the present application, the second channel 120 can extend linearly, and there is a first angle between the extension direction of the second channel 120 and the first direction, the first angle is less than 90°, and the first angle is preferably within the range of 30° to 60°. If the first angle is too large, the bile duct sub-scope needs to be bent at a large angle in the process of probing the bile duct sub-scope into the second channel 120, and there is a problem of large resistance in the process of pushing the bile duct sub-scope, which is not conducive to smoothly pushing the bile duct sub-scope into the common bile duct; and if the first angle is small, due to the radial size and wall thickness of the sheath body 100, it is difficult for the distal end of the bile duct sub-scope to reach a bending amplitude that matches the entrance of the common bile duct, which also increases the difficulty of probing the bile duct sub-scope.

[0032] In the examples of this application, see Figure 2The second channel 120 is curved and extended in an arc shape. In this way, when the insertion portion of the choledochoscope is controlled to bend and pushed into the second channel 120, the shape of the insertion portion in the bent state is consistent with the second channel 120. The arc-shaped design enables the choledochoscope to move more smoothly along the curved shape of the second channel 120 during the pushing process, thereby reducing the friction resistance generated during the pushing process, helping the operator to operate the choledochoscope more easily during the operation and improving work efficiency.

[0033] For further technical solutions, see Figure 2 , Figure 3 and Figure 4 The second channel 120 with an arc-shaped curved design has a second angle between the tangent direction at the distal end and the first direction, and the second angle is less than or equal to 90°. In this way, the choledochoscope can face forward or sideways when it just extends out of the second channel 120, and the choledochoscope can be controlled to make the insertion portion further bent when extending out of the second channel 120, and the distal end of the choledochoscope can face backward, thereby allowing the distal end of the choledochoscope to have a larger angle adjustment range after passing through the second channel 120, so that the choledochoscope can more accurately find the entrance position of the common bile duct within a larger angle adjustment range, thereby improving the convenience of the choledochoscope in extending into the common bile duct.

[0034] For further technical solutions, see Figure 4 The sheath body 100 has an arc-shaped transition at the connection point between the first channel 110 and the second channel 120. When the operator controls the choledochoscope to bend and probe into the second channel 120, the choledochoscope will be subjected to friction and extrusion by the inner wall of the sheath body 100. The arc-shaped transition design can disperse these friction and extrusion forces, reduce the impact and wear of the inner wall of the sheath body 100 on the choledochoscope, thereby protecting the choledochoscope from damage and extending its service life.

[0035] In some embodiments of the present application, the wall thickness of the sheath body 100 can be kept consistent along the circumferential direction of the sheath body 100 , thereby improving the convenience of manufacturing the sheath body 100 and effectively reducing the production cost of the sheath body 100 .

[0036] In some other embodiments of the present application, the wall thickness of the sheath body 100 may also be different along the circumferential direction of the sheath body 100. For details, see Figure 2 , Figure 3 and Figure 4Along the radial direction of the sheath body 100, the sheath body 100 has a first part 101 and a second part 102 distributed on both sides of the first channel 110, that is, the first part 101 and the second part 102 are radially opposite to each other, and the second channel 120 is arranged in the second part 102. At the position where the first channel 110 and the second channel 120 are connected, the thickness of the second part 102 is greater than the thickness of the first part 101. Under such a setting, when the biliary sub-scope is operated to bend and probe into the second channel 120, the biliary sub-scope will generate obvious squeezing force on the sheath body 100. Through the thickening design of the second part 102, the structural strength of the sheath body 100 at the connection point between the first channel 110 and the second channel 120 can be increased, thereby avoiding forcing the sheath body 100 to bend and collapse when the biliary sub-scope is bent and probed into the second channel 120 or the common bile duct, thereby ensuring the stability of the sheath body 100 in providing support for the biliary sub-scope.

[0037] For further technical solutions, see Figure 7 and Figure 8 The thickness of the second portion 102 at the connection point between the first channel 110 and the second channel 120 is greater than the thickness of the second portion 102 at the proximal portion of the connection point. That is to say, along the aforementioned first direction, the first channel 110 is not of equal caliber, and the caliber of the first channel 110 at the proximal portion is smaller than the caliber at the connection point. When the biliary sub-scope is pushed or withdrawn in the first channel 110 and / or the second channel 120, the friction contact area between the biliary sub-scope and the sheath body 100 can be reduced, thereby ensuring the smoothness of pushing or withdrawing the biliary sub-scope.

[0038] In a preferred embodiment, the caliber of the first channel 110 at the connection point matches the diameter of the choledioscope. In this way, when the choledioscope is inserted into the common bile duct, this matching characteristic can reduce the shaking of the distal end of the choledioscope, which is conducive to more precise operation of the choledioscope, thereby ensuring the certainty of the sheath body 100 supporting the choledioscope.

[0039] It should be noted that, in the embodiment of the present application, the caliber of the first channel 110 at the proximal end of the connection is smaller than the caliber of the first channel 110 at the connection, and this caliber change in the first direction can be gradual or segmental, and the present application does not impose specific restrictions on this. In a preferred embodiment, the caliber change of the first channel 110 in the first direction is gradual. Under such a setting, compared with the segmental caliber change, the gradual caliber change can avoid the formation of a step surface, thereby ensuring the smoothness of the insertion of the choledochoscope.

[0040] See also Figure 3 , Figure 4 , Figure 5 and Figure 6The sheath may further include a guide tube 200, which is movably arranged in the sheath body 100. A curved section 210 is provided at the distal end of the guide tube 200, and the curved section 210 can be inserted into the second channel 120, thereby guiding the choledochoscope to be laterally extended from the second channel 120.

[0041] In some embodiments of the present application, the bending section 210 may be pre-bent. For example, the bending section of the guide tube 200 may be made of a shape memory alloy, and in a natural state, the bending section 210 is in a bent posture relative to the entire guide tube 200 . In the initial state, when the guide tube 200 is inserted into the first channel 110, and the distal end of the guide tube 200 exceeds the connection between the first channel 110 and the second channel 120, the biliary sub-scope is in the guide tube 200 and observes the front of the sheath body 100. When the biliary sub-scope needs to be inserted into the common bile duct from the side, the operator can retract the guide tube 200. When the head end of the guide tube 200 is located at the connection between the first channel 110 and the second channel 120, the curved section 210 of the guide tube 200 can automatically bend and press into the second channel 120. The operator then pushes the guide tube 200. At this time, the biliary sub-scope in the guide tube 200 can naturally insert into the second channel 120 and can be further pushed out.

[0042] It can be understood that, in the case where the curved section 210 of the guide tube 200 is pre-curved, when the distal end of the guide tube 200 is preset beyond the connecting point in the first channel 110, human assistance is required to constrain the curved section 210 to prevent the curved section 210 from automatically entering the second channel 120 during the insertion of the guide tube 200.

[0043] In some other embodiments of the present application, the bending section 210 can also be actively bent by manual operation. For example, the bending section 210 is connected to a traction member, which may be a traction rope. The distal end of the traction rope is connected to the side of the bending section 210 facing the second channel 120. The operator can pull the traction member to make the bending section 210 probe into the second channel 120, thereby guiding the choledochoscope. It will not be repeated here.

[0044] As can be seen from the foregoing, along the first direction, the caliber of the first channel 110 can be gradual. Based on this, in some embodiments of the present application, the caliber of the guide tube 200 along the first direction is gradual, which can improve the convenience of inserting the guide tube 200 into the first channel 110. After the operator performs the backing and pushing actions in sequence, the guide tube 200 at this time can have a better fit with the gradual first channel 110, which can prevent the guide tube 200 from jumping to the distal end, thereby ensuring the accuracy and stability when operating the choledochoscope.

[0045] See also Figure 1 and Fig. 9 The sheath of the embodiment of the present application may further include a sheath seat 300, which includes a base 310 and a movable portion 320 slidably disposed on the base 310. When the sheath includes a guide tube 200, the proximal end of the sheath body 100 is connected to the base 310, and the proximal end of the guide tube 200 is connected to the movable portion 320. By sliding the movable portion 320 to move it relative to the base 310, the guide tube 200 can be pushed and retracted in the sheath body 100.

[0046] In a further technical solution, when the sheath includes the guide tube 200 and the curved section 210 of the guide tube 200 needs to be manually controlled to be actively bent, a knob 330 is further provided on the movable portion 320, the distal end of the aforementioned traction member is connected to the curved section 210, and the proximal end of the traction member is transmission-connected to the knob 330, and the bending of the curved section 210 can be achieved by turning the knob 330. Exemplarily, a traction wheel coaxially connected to the knob 330 is provided in the movable portion 320, and the proximal end of the traction member is fixedly connected to the traction wheel.

[0047] The embodiment of the present application further discloses an endoscope system, which includes an endoscope and the aforementioned sheath, and an insertion portion of the endoscope is inserted into the first channel 110 or the second channel 120 .

[0048] It should be noted that, in this article, the terms "comprise", "include" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise one..." do not exclude the presence of other identical elements in the process, method, article or device including the element. 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 reverse order according to the functions involved, for example, the described method may be performed in an order different from that described, and various steps may also be added, omitted, or combined. In addition, the features described with reference to certain examples may be combined in other examples.

[0049] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A sheath, characterized in that: The invention comprises a sheath body (100), wherein the sheath body (100) has a first channel (110) which runs through the sheath body along its axial direction, and the sheath body (100) is also provided with a second channel (120), wherein the second channel (120) is distributed at the distal end of the sheath body (100), one end of the second channel (120) is connected to the first channel (110), and the other end of the second channel (120) radially passes through the sheath body (100).

2. The sheath according to claim 1, characterized in that: The second channel (120) extends linearly, and there is a first angle between the extension direction of the second channel (120) and the first direction, the first angle is less than 90°, and the first direction is the extension direction of the sheath body (100) from its proximal end to its distal end; Alternatively, the second channel (120) extends in an arc shape, and a second angle is formed between a tangent direction at a distal end of the second channel (120) and the first direction, the second angle is less than or equal to 90°, and the first direction is an extension direction of the sheath body (100) from its proximal end to its distal end.

3. The sheath according to claim 2, characterized in that: The sheath body (100) has an arc-shaped transition at the connection point between the first channel (110) and the second channel (120).

4. The sheath according to claim 3, characterized in that: Along the radial direction of the sheath body (100), the sheath body (100) comprises a first portion (101) and a second portion (102) distributed on both sides of the first channel (110); the second channel (120) is arranged in the second portion (102); and at the connection point between the first channel (110) and the second channel (120), the thickness of the second portion (102) is greater than the thickness of the first portion (101).

5. The sheath according to claim 4, characterized in that: The thickness of the second portion (102) at the connection point between the first channel (110) and the second channel (120) is greater than the thickness of the second portion (102) distributed at the proximal end of the connection point.

6. The sheath according to any one of claims 1 to 5, characterized in that: Also included is a guide tube (200), wherein the distal end of the guide tube (200) has a curved section (210); The bending section (210) is pre-bent, and when the bending section (210) is located at the connecting point between the first channel (110) and the second channel (120), the bending section (210) bends toward the second channel (120) to penetrate into the second channel (120); Alternatively, the bending section (210) is connected to a traction member, and the traction member is configured to pull the bending section (210) to bend, so that the bending section (210) is located in the first channel (110) or extends into the second channel (120).

7. The sheath according to claim 6, characterized in that: Along a first direction, the diameter of the guide tube (200) gradually decreases, and the first direction is the extension direction of the sheath body (100) from its proximal end to its distal end.

8. The sheath according to claim 6, characterized in that: It also includes a sheath seat (300), the sheath seat (300) including a base (310) and a movable part (320) slidably arranged on the base (310), the proximal end of the sheath body (100) is connected to the base (310), and the guide tube (200) is connected to the movable part (320).

9. The sheath according to claim 8, characterized in that: The movable portion (320) is also provided with a knob (330), and the knob (330) is transmission-connected to the bending section (210) through the traction member to control the bending of the bending section (210).

10. An endoscope system, characterized in that: It comprises an endoscope and a sheath as claimed in any one of claims 1 to 9, wherein the insertion portion of the endoscope is inserted into the first channel (110) or the second channel (120).

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