CN219516511U - Sheath structure and resectoscope - Google Patents

Abstract

The utility model relates to a sheath structure and an electrotome. The sheath body structure comprises an elliptical outer sheath tube and an inner sheath tube penetrating through the outer sheath tube. The gap is arranged between the inner sheath tube and the outer sheath channel of the outer sheath tube, so that after the injection flows into the inner sheath channel from the liquid inlet, the injection can flow into the outer sheath channel from the gap and flow out from the liquid outlet, and the turbid injection is discharged. Because the outer sheath tube and the inner sheath tube are oval, the gap between the tube wall of the sheath tube and the urethral cavity wall is larger, the liquid inlet or the liquid outlet is not easy to be blocked by human tissues, the flowing effect of the injection is better, the timely inflow of clean injection and the timely discharge of turbid injection are facilitated, the definition of the operation visual field is improved, the operation efficiency is further improved, and the operation risk is reduced. Meanwhile, as the gap between the tube wall of the sheath tube and the urethral cavity wall is larger, the contact area between the tube wall of the sheath tube and the urethral cavity wall is smaller, so that discomfort brought to a human body in the sheath tube inserting process can be reduced, and the use convenience is improved.

Description

Sheath structure and resectoscope

Technical Field

The utility model relates to the technical field of medical instruments, in particular to a sheath structure and an electrotome.

Background

The resectoscope is widely applied to the treatment of pathological tissues such as prostatic hyperplasia, bladder tumor, hysteromyoma, polyp and the like clinically, mainly enters the human body cavity through the human urethra to perform operation treatment on target tissues, and belongs to the minimally invasive operation of underwater electrosurgery.

During operation, injection liquid such as physiological saline is injected through the inner sheath and the outer sheath to expand and flush the cavity, and the injection liquid is used as an operation working medium; meanwhile, turbid water in the cavity naturally flows out by utilizing the special structure of the inner sheath and the outer sheath, and forms continuous convection with the liquid inlet, thereby being beneficial to clear surgical field and convenient for doctors to diagnose target tissues.

Because human tissue has certain elasticity, the drain hole contacted with the human tissue is blocked, and turbid injection in the cavity cannot be discharged in time, so that the operation visual field is unclear, the operation efficiency is affected, the operation risk is increased, and the problem of inconvenient use exists.

Disclosure of Invention

Accordingly, it is necessary to provide a sheath structure which solves the problem of inconvenience in use of the conventional sheath structure.

A sheath structure for use with an resectoscope, the sheath structure comprising:

an outer sheath mechanism comprising an elliptical outer sheath; the outer sheath tube is provided with an outer sheath channel and a liquid outlet communicated with the outer sheath channel;

an inner sheath mechanism comprising an elliptical inner sheath; the inner sheath tube is provided with an inner sheath channel and a liquid inlet communicated with the inner sheath channel; the inner sheath tube penetrates through the outer sheath channel, and a gap is formed between the inner sheath tube and the outer sheath channel, so that an injection liquid can sequentially pass through the liquid inlet, the inner sheath channel, the outer sheath channel and the liquid outlet.

In one embodiment, the sheath mechanism further comprises a sheath lock coupled to the sheath, the sheath lock configured to operably move to snap-fit with the inner sheath.

In one embodiment, the sheath mechanism further comprises a limiting member connected to the sheath tube, wherein the limiting member is used for abutting against human tissue so as to limit the movement of the sheath tube along the axial direction of the sheath tube.

In one embodiment, the sheath mechanism further comprises a water outlet valve and a sheath seat connected to the sheath tube, and the water outlet is arranged on the sheath seat; the water outlet valve is connected with the liquid outlet; and/or

The inner sheath mechanism further comprises a water inlet valve and an inner sheath seat connected with the inner sheath pipe, and the liquid inlet is arranged on the inner sheath seat; the water inlet valve is connected with the liquid inlet.

In one embodiment, the inner sheath mechanism further comprises an inner sheath connector connected to the inner sheath tube; the inner sheath connecting piece is provided with a clamping part which is used for being connected with an external instrument;

the inner sheath connector is configured to operably rotate in a circumferential direction of the inner sheath to change a position of the clip portion in the circumferential direction.

In one embodiment, the sheath structure further comprises a obturator comprising an oval plunger tube disposed through the inner sheath channel.

In one embodiment, the obturator is configured with an obturator lock member coupled to the plunger tube, the obturator lock member being configured to operably move to engage the engagement portion.

In one embodiment, the outer sheath is configured with a plurality of drain holes, each of which communicates with the outer sheath channel.

In one embodiment, a plurality of the drain holes are arranged at intervals in the circumferential direction and/or the axial direction of the outer sheath tube.

An resectoscope comprising an endoscope and a sheath structure as described above, the endoscope being connected to the sheath structure.

The sheath structure applied to the resectoscope comprises an outer sheath mechanism and an inner sheath mechanism. The sheath mechanism comprises an elliptical sheath tube, and the sheath tube is provided with a sheath channel and a liquid outlet. The inner sheath mechanism comprises an elliptical inner sheath tube, and the inner sheath tube is provided with an inner sheath channel and a liquid inlet. Because the gap is arranged between the inner sheath tube and the outer sheath channel, namely, the gap is arranged between the outer wall of the inner sheath tube and the inner wall of the outer sheath tube, the gap forms a flow channel, so that injection can flow from the gap to the outer sheath channel after flowing into the inner sheath channel from the liquid inlet, and flow out from the liquid outlet, and the turbid injection is discharged. Because the outer sheath tube and the inner sheath tube are oval, compared with the round design, the gap between the tube wall of the sheath tube and the wall of the urethral cavity is larger, and the liquid inlet or the liquid outlet is not easy to be blocked by human tissues, so that the flowing effect of the injection is better, the timely inflow of clean injection and the timely discharge of turbid injection are facilitated, the definition of the operation visual field is improved, the operation efficiency is further improved, and the operation risk is reduced. Meanwhile, as the gap between the tube wall of the sheath tube and the urethral cavity wall is larger, the contact area between the tube wall of the sheath tube and the urethral cavity wall is smaller, so that discomfort brought to a human body in the sheath tube inserting process can be reduced, and the use convenience is improved.

Drawings

FIG. 1 is a schematic view of a sheath structure according to an embodiment of the present utility model;

FIG. 2 is a cross-sectional view of the sheath structure shown in FIG. 1;

FIG. 3 is a schematic view of the outer sheath mechanism of the sheath structure of FIG. 1 in another view;

FIG. 4 is a cross-sectional view of the outer sheath mechanism in the sheath configuration shown in FIG. 3;

FIG. 5 is a cross-sectional view of the inner sheath mechanism in the sheath configuration shown in FIG. 2;

fig. 6 is a cross-sectional view of the obturator in the sheath configuration shown in fig. 2.

Reference numerals: 10-sheath structure; 100-an outer sheath mechanism; 110-an outer sheath; 111-drainage holes; 112-an outer sheath channel; 120-outer sheath locking member; 130-a limiting piece; 140-an outer sheath seat; 150-a water outlet valve; 160-an outer sheath handle; 200-an inner sheath mechanism; 210-an inner sheath; 211-inner sheath channel; 220-inner sheath connector; 221-a clamping part; 230-inlet valve; 240-inner sheath seat; 250-sealing rings; 260-inner sheath lock; 270-blocking ring; 280-inner sheath liner; 300-obturator; 310-plunger tube; 320-closed cell locking member; 330-closed cell handle; 340-a closed cell liner; 350-closed cell handle.

Detailed Description

In order that the above objects, features and advantages of the utility model will be readily understood, a more particular description of the utility model will be rendered by reference to the appended drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present utility model. The present utility model may be embodied in many other forms than described herein and similarly modified by those skilled in the art without departing from the spirit of the utility model, whereby the utility model is not limited to the specific embodiments disclosed below.

In the description of the present utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present utility model and simplifying the description, and do not indicate or imply that the device or element being referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present utility model.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In the description of the present utility model, the meaning of "plurality" means at least two, for example, two, three, etc., unless specifically defined otherwise.

In the present utility model, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. The specific meaning of the above terms in the present utility model can be understood by those of ordinary skill in the art according to the specific circumstances.

In the present utility model, unless expressly stated or limited otherwise, a first feature "up" or "down" a second feature may be the first and second features in direct contact, or the first and second features in indirect contact via an intervening medium. Moreover, a first feature being "above," "over" and "on" a second feature may be a first feature being directly above or obliquely above the second feature, or simply indicating that the first feature is level higher than the second feature. The first feature being "under", "below" and "beneath" the second feature may be the first feature being directly under or obliquely below the second feature, or simply indicating that the first feature is less level than the second feature.

It will be understood that when an element is referred to as being "fixed" or "disposed" on another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like are used herein for illustrative purposes only and are not meant to be the only embodiment.

FIG. 1 is a schematic view showing a sheath structure according to an embodiment of the present utility model, and FIG. 2 is a cross-sectional view showing the sheath structure shown in FIG. 1; FIG. 3 is a schematic view of the outer sheath mechanism of the sheath structure of FIG. 1 in another view; FIG. 4 is a cross-sectional view of the outer sheath mechanism in the sheath configuration shown in FIG. 3; fig. 5 is a cross-sectional view of the inner sheath mechanism in the sheath configuration shown in fig. 2.

Referring to fig. 1 to 5, a sheath structure 10 according to an embodiment of the present utility model is applied to an resectoscope, where the sheath structure 10 includes an outer sheath mechanism 100 and an inner sheath mechanism 200. The sheath mechanism 100 includes an oval-shaped sheath tube 110; the outer sheath 110 is configured with an outer sheath channel 112 and a liquid outlet communicating with the outer sheath channel 112. The inner sheath mechanism 200 includes an elliptical inner sheath 210; the inner sheath 210 is configured with an inner sheath channel 211 and a liquid inlet communicating with the inner sheath channel 211; the inner sheath 210 is disposed through the outer sheath channel 112 with a gap therebetween, so as to form a flow path through which the injection liquid can sequentially pass through the liquid inlet, the inner sheath channel 211, the outer sheath channel 112 and the liquid outlet.

Since there is a gap between the inner sheath 210 and the outer sheath channel 112, that is, a gap between the outer wall of the inner sheath 210 and the inner wall of the outer sheath 110, the gap forms a flow channel. Therefore, after the injection liquid flows into the inner sheath channel 211 from the liquid inlet, the injection liquid can flow into the outer sheath channel 112 from the gap and flow out from the liquid outlet, so that the turbid injection liquid can be discharged. Because outer sheath 110 and inner sheath 210 are oval, compare in circular design, the clearance between sheath's pipe wall and the urethra chamber wall is great, and inlet or liquid outlet are difficult for being blocked by human tissue for the flow effect of injection is better, is favorable to the timely inflow of clean injection and the timely discharge of turbid injection, promotes the definition of operation field, and then promotes operation efficiency, reduces the operation risk. Meanwhile, as the gap between the tube wall of the sheath tube and the urethral cavity wall is larger, the contact area between the tube wall of the sheath tube and the urethral cavity wall is smaller, so that discomfort brought to a human body in the sheath tube inserting process can be reduced, and the use convenience is improved.

As shown in fig. 1 to 4, in an embodiment, the outer sheath 110 and the inner sheath 210 are hollow structures with both ends open. The long axis of the outer sheath 110 is 1.1 times to 1.5 times the short axis in the radial direction. The length of the outer sheath 110 is about 170mm to 190mm in the axial direction. The outer sheath 110 is generally made of a soft material such as resin, plastic or silica gel. Therefore, the outer sheath 110 can be elastically deformed to some extent, facilitating the entry of the outer sheath 110 into human tissue. The end of the inner sheath 210 is a high temperature resistant insulating ceramic head, and the size of the inner sheath 210 can be designed by referring to the outer sheath 110, which will not be described herein.

In yet another embodiment, the outer sheath includes a flexible segment and a rigid segment in communication with one another. The flexible section and the rigid section may be of different materials. The flexible section can be formed by rubber and silica gel, and the hard section can be formed by hard plastic, and the flexible section and the hard section are connected by gluing after being formed respectively. The flexible section can be bent into any angle, and the hard section is convenient for an operator to grasp. The two are matched, so that the outer sheath tube can smoothly extend into human tissues.

As shown in fig. 1, in one embodiment, the outer sheath tube 110 is configured with a plurality of drain holes 111, each drain hole 111 communicating with the outer sheath channel 112. By providing a plurality of drain holes 111, the waste liquid in the sheath channel 112, i.e., turbid injection liquid, is conveniently guided to a liquid outlet and discharged. Wherein, the drain hole 111 and the liquid outlet are respectively located at two ends of the outer sheath tube 110 along the axial direction.

As shown in fig. 1, in one embodiment, a plurality of drain holes 111 are arranged at intervals along the circumferential direction of the outer sheath 110. Through this kind of setting for waste liquid is comparatively even along circumference derivation, increases the flow space of waste liquid, promotes the flow effect of waste liquid.

In still another embodiment, as shown in fig. 1, a plurality of drain holes 111 are arranged at intervals along the axial direction of the outer sheath tube 110. With this arrangement, the speed of discharging the waste liquid from the drain hole 111 is increased. By providing the plurality of sets of drain holes 111, the discharge speed and the discharge effect of the waste liquid are improved, and the influence on the definition of the endoscope field of view is avoided.

As shown in fig. 2 and 4, in one embodiment, the sheath mechanism 100 further includes a water outlet valve 150 and a sheath seat 140 connected to the sheath tube 110, and the water outlet is disposed on the sheath seat 140; the outlet valve 150 is connected to the outlet. By providing the water outlet valve 150, the discharge of the waste liquid is conveniently controlled. The outer sheath holder 140 is provided with a through hole for the outer sheath 110 to pass through. The connection manner between the outer sheath 110 and the outer sheath 140 may be a fitting, bonding or welding, and the connection manner between the outer sheath 110 and the outer sheath 140 may be an integral structural design, which is not described herein.

In one embodiment, as shown in fig. 2 and 4, one end of the outer sheath 110 is of a diverging design, i.e., the tube diameter increases gradually. So, can improve the liquid flow, and then improved the convection current effect between liquid outlet and the inner sheath inlet. Meanwhile, compared with the arrangement that the outer sheath 110 is of a single pipe diameter, when the unstable connection such as the desoldering of the outer sheath 110 of the single pipe diameter occurs, the outer sheath 110 is easy to separate from the outer sheath seat 140 to cause medical accidents, and the end part of the outer sheath 110 is arranged into a gradually expanding section which can be clamped in the through hole of the outer sheath seat 140, so that the connection stability between the outer sheath 110 and the outer sheath seat 140 is improved.

As shown in fig. 2 and 4, in one embodiment, the sheath mechanism 100 further includes a sheath lock 120 coupled to the sheath tube 110, the sheath lock 120 being configured to operably move to snap-fit with the inner sheath tube 210.

The sheath locking member 120 may specifically be a sheath knob, where the sheath holder 140 is provided with threads, and the sheath knob is screwed on the sheath holder 140. Wherein the sheath locking member 120 is of an L-shaped design such that its ends form hooks. The inner sheath mechanism 200 is provided with a clamping groove, and the hook is clamped with the clamping groove by rotating the outer sheath locking piece 120, so that the outer sheath mechanism 100 and the inner sheath mechanism 200 are connected. Further, the sheath mechanism 100 further includes a sheath handle 160 coupled to the sheath lock 120, and by providing the sheath handle 160, rotation of the sheath lock 120 is facilitated.

As shown in fig. 2 and 4, in one embodiment, the sheath mechanism 100 further includes a limiting member 130 connected to the outer sheath 110, and the limiting member 130 is configured to abut against human tissue during implantation to limit the movement of the outer sheath 110 along its own axis, so as to avoid the sheath structure 10 from being implanted too deeply and damaging the urethral tissue.

As shown in fig. 2 and 5, in one embodiment, the inner sheath mechanism 200 further includes a water inlet valve 230 and an inner sheath base 240 connected to the inner sheath 210, and the liquid inlet is disposed on the inner sheath base 240; the inlet valve 230 is connected to the inlet.

By providing the water inlet valve 230, the introduction of the injection is conveniently controlled. The inner sheath holder 240 is provided with a through hole for the inner sheath 210 to pass therethrough. The connection between the inner sheath 210 and the inner sheath 240 may be a fitting, bonding or welding, and the inner sheath 210 and the inner sheath 240 may be an integral structure.

In one embodiment, as shown in fig. 2 and 5, one end of the inner sheath 210 is of a diverging design, i.e., the tube diameter increases gradually. By setting the end of the inner sheath 210 as a divergent section, the divergent section can be clamped in the through hole of the inner sheath seat 240, so that the connection stability between the inner sheath 210 and the inner sheath seat 240 is improved.

As shown in fig. 2 and 5, in one embodiment, the inner sheath mechanism 200 further includes an inner sheath connector 220 coupled to the inner sheath 210; the inner sheath connector 220 is configured with a clamping portion 221, the clamping portion 221 being for connection with an external instrument. The inner sheath connector 220 is configured to operably rotate in the circumferential direction of the inner sheath 210 to change the position of the clip portion 221 in the circumferential direction. Through this kind of setting for inner sheath connecting piece 220 can be along circumference rotation to arbitrary direction, the joint portion 221 of being convenient for and external instrument or obturator 300 joint, convenient installation and use. The engagement portion 221 may be a recessed locking groove.

As shown in fig. 2 and 5, in one embodiment, the inner sheath mechanism 200 further includes an inner sheath lock 260, the inner sheath lock 260 being threadably coupled to the inner sheath mount 240. The inner sheath lock 260 may be specifically an inner sheath knob, and the inner sheath connector 220 is compressed by tightening the inner sheath knob to the left. Further, the inner sheath mechanism 200 further includes a blocking ring 270, the blocking ring 270 is disposed between the inner sheath seat 240 and the inner sheath lock 260, so as to avoid a gap between the inner sheath seat 240 and the inner sheath lock 260 due to connection, and improve the sealing effect of the inner sheath mechanism 200. Further, an inner sheath bushing 280 is provided between the inner sheath connector 220 and the inner sheath holder 240 to reduce contact wear therebetween.

As shown in fig. 2 and 5, in one embodiment, the inner sheath mechanism 200 further includes a sealing ring 250, where the sealing ring 250 is disposed between the inner sheath connector 220 and the inner sheath lock 260, so as to prevent the injection injected from leaking out of the injection inlet, and perform a sealing and waterproof function. Specifically, sealing ring 250 is the rubber material for sealing ring 250 has certain elasticity, compares current structure and uses the metal contact surface to carry out the liquid seal effect better, and is more convenient to the change of sealing ring 250 in the future moreover, has solved later stage maintenance and has dismantled the time and labor-consuming scheduling problem, has reduced cost of maintenance.

In one embodiment, the inner sheath mechanism is rotatable within the outer sheath channel about an axis of the outer sheath; so that the inner sheath mechanism can rotate within the outer sheath channel. Therefore, when the target tissues in different directions are treated, only the inner sheath mechanism is required to be rotated without rotating the outer sheath mechanism, so that the rotating contact damage of the sheath structure to the urethra is reduced; when the inner sheath mechanism rotates relative to the outer sheath mechanism, the inner sheath mechanism is still in sealing connection with the outer sheath mechanism, so that liquid leakage in the treatment process is avoided. The inner sheath mechanism and the outer sheath mechanism may be rotatably mounted by a rotation mechanism, which may be a mechanism for sealing rotation of a sealing cylinder or the like, and is not specifically shown here.

Fig. 6 is a cross-sectional view of the obturator 300 in the sheath structure 10 shown in fig. 2. As shown in fig. 1, 2 and 6, in one embodiment, the sheath structure 10 further includes a obturator 300, the obturator 300 including an oval plunger tube 310, the plunger tube 310 passing through the inner sheath channel 211. The obturator 300 is used to occlude the inner sheath 210 during insertion into the urethra to avoid scratching the urethra. By providing plunger tube 310 with an oval shape to fit within inner sheath 210.

As shown in fig. 2, 5 and 6, in one embodiment, obturator 300 is configured with obturator lock 320 attached to plunger tube 310, obturator lock 320 being configured to operably move to snap into engagement with snap 221 as previously described. Specifically, the end of the closed hole locking member 320 is designed as a hook, and the clamping portion 221 on the inner sheath connecting member 220 is designed as a groove, and the two parts are clamped and matched.

As shown in fig. 2 and 6, in one embodiment, the obturator 300 includes an obturator handle 350, and the obturator handle 350 is configured to facilitate an operator to grasp the obturator 300 to achieve a stable grip. Further, the obturator 300 further includes an obturator handle 330, and by providing the obturator handle 330, the obturator lock 320 is conveniently rotated, thereby reducing the difficulty of operation. Further, the obturator 300 further includes an obturator bushing 340 disposed between the obturator handle 350 and obturator lock 320 to reduce contact wear and increase service life

In the above-mentioned sheath structure 10, during use, the inner sheath tube 210 may be inserted into the outer sheath tube 110, and the outer sheath locking member 120 is operated to connect the outer sheath locking member 120 with the clamping groove on the inner sheath seat 240. And then the plunger tube 310 is inserted into the inner sheath tube 210, and the closed hole locking member 320 is clamped with the locking groove on the inner sheath connector 220 by operating the closed hole locking member 320. The assembled sheath structure 10 is implanted into the urethra to reach the prostatic lesion. Next, the obturator lock 320 on the obturator 300 is twisted to disengage the obturator 300 from the inner sheath connector 220. An electrotome electrode or applicator is placed into the sheath structure 10 and connected to the inner sheath connector 220 via a locking portion (the shape of the locking portion being similar to the shape of the obturator 320) on the bridge or applicator. Further, the endoscope is connected to the connection bridge or the use instrument is connected by an endoscope lock. Finally, the inflow valve 230 and the outflow valve 150 are opened, and water flows through the inner sheath 210 into the urethra and out the drainage hole 111 at the end of the outer sheath 110 to perform surgical operations of electrotomy and other instruments in the endoscopic view.

Further, an embodiment of the present utility model further provides an resectoscope, which includes an endoscope and the sheath structure 10, and the endoscope is connected to the sheath structure 10. The sheath structure 10 of any embodiment of the electrotome can enable the flowing effect of the injection to be good, is favorable for timely inflow of clean injection and timely discharge of turbid injection, improves the definition of an operation visual field, improves the operation efficiency, and reduces the operation risk. Meanwhile, as the gap between the tube wall of the outer sheath tube and the wall of the urethral cavity is larger, the contact area between the tube wall of the outer sheath tube and the wall of the urethral cavity is smaller, so that discomfort brought to a human body in the insertion process of the outer sheath tube can be reduced, and the use convenience is improved.

The technical features of the above-described embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above-described embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.

The above examples illustrate only a few embodiments of the utility model, which are described in detail and are not to be construed as limiting the scope of the utility model. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the utility model, which are all within the scope of the utility model. Accordingly, the scope of protection of the present utility model is to be determined by the appended claims.

Claims (10)

1. The utility model provides a sheath body structure, is applied to the resectoscope, its characterized in that, sheath body structure includes:

a sheath mechanism (100) comprising an elliptical sheath tube (110); the outer sheath tube (110) is provided with an outer sheath channel (112) and a liquid outlet communicated with the outer sheath channel (112);

an inner sheath mechanism (200) comprising an elliptical inner sheath (210); the inner sheath tube (210) is provided with an inner sheath channel (211) and a liquid inlet communicated with the inner sheath channel (211); the inner sheath tube (210) is arranged in the outer sheath channel (112) in a penetrating manner, and a gap is formed between the inner sheath tube and the outer sheath channel, so that an injection liquid can sequentially pass through the liquid inlet, the inner sheath channel (211), the outer sheath channel (112) and the liquid outlet.

2. The sheath structure according to claim 1, wherein the sheath mechanism (100) further comprises a sheath lock (120) coupled to the sheath tube (110), the sheath lock (120) being configured to operably move to snap-fit with the inner sheath tube (210).

3. The sheath structure according to claim 1, wherein the outer sheath mechanism (100) further comprises a stopper (130) connected to the outer sheath (110), the stopper (130) being adapted to abut against human tissue to limit movement of the outer sheath (110) in its own axial direction.

4. The sheath structure according to claim 1, wherein the sheath mechanism (100) further comprises a water outlet valve (150) and a sheath seat (140) connected to the sheath tube (110), the water outlet being provided in the sheath seat (140); the water outlet valve (150) is connected with the liquid outlet; and/or

The inner sheath mechanism (200) further comprises a water inlet valve (230) and an inner sheath seat (240) connected with the inner sheath tube (210), and the liquid inlet is arranged on the inner sheath seat (240); the inlet valve (230) is connected to the inlet.

5. The sheath structure according to claim 1, wherein the inner sheath mechanism (200) further comprises an inner sheath connector (220) connected to the inner sheath tube (210); the inner sheath connecting piece (220) is provided with a clamping part (221), and the clamping part (221) is used for being connected with an external instrument;

the inner sheath connector (220) is configured to operably rotate in a circumferential direction of the inner sheath tube (210) to change a position of the clip portion (221) in the circumferential direction.

6. The sheath structure according to claim 5, further comprising a obturator (300), the obturator (300) comprising an oval plunger tube (310), the plunger tube (310) being threaded through the inner sheath channel (211).

7. The sheath structure according to claim 6, wherein the obturator (300) is configured with an obturator lock (320) connected to the plunger tube (310), the obturator lock (320) being configured to operably move to engage the engagement portion (221).

8. The sheath structure according to claim 1, wherein the outer sheath tube (110) is configured with a plurality of drain holes (111), each drain hole (111) being in communication with the outer sheath channel (112).

9. The sheath structure according to claim 8, wherein a plurality of the drainage holes (111) are arranged at intervals in the circumferential direction and/or the axial direction of the outer sheath tube (110).

10. An resectoscope comprising an endoscope and a sheath structure (10) as claimed in any one of claims 1 to 9, the endoscope being connected to the sheath structure (10).