Medical Clips

Abstract

To provide a medical clip being usable in an endoscope clip device and usable in both of hemostasis and marking, allowing an operator to redo opening and closing the clip until the clip is fully closed.SOLUTION: A leaf spring-like medical clip 1A comprising a first arm 10 and a second arm 20 facing each other, and a continuous part 30 between one end of the first arm 10 and one end of the second arm 20, comprises a pair of hook-like protrusions 12a and 12b that can latch both sides of the second arm 20, at a central part in the longitudinal direction of the first arm 10. When the first arm 10 and the second arm 20 come close to each other to a prescribed distance, the pair of hook-like protrusions 12a and 12b latch both sides of the second arm 20 to hold a proximity state of the first arm 10 and the second arm 20.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a medical clip. [Background technology]

[0002] Conventionally, medical clips have been used by attaching them to endoscopic clip devices as hemostatic clips or as marker clips for identifying the location of affected areas during surgery. For example, there are known clips that consist of a clip body made by bending a metal leaf spring such as stainless steel into a roughly ">" shape and a crimping ring that fits over the clip body to close it (Patent Document 1), and clips that are made of resin by forming the clip body into a specific shape (Patent Document 2).

[0003] In addition, there is a hemostatic clip that is made of an elastic material and has a hook at the tip thereof and a structure that fits onto the hook, so that the clip can be closed without using a crimping ring (Patent Document 3). This hemostatic clip is opened and closed using a forceps-type instrument. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6572229 [Patent Document 2] Patent No. 6675674 [Patent Document 3] Japanese Patent Application Publication No. 56-3048 Summary of the Invention [Problem to be solved by the invention]

[0005] Conventional clips using the crimping ring described in Patent Documents 1 and 2 are attached to the clip sheath of an endoscopic clip device and are opened and closed by the operation of the clip device. For example, as shown in FIG. 16A of the present application, this clip 1X is attached to the inner sheath 41 of the clip sheath 40, and the operation wire 43 is connected by a connecting portion 44. By pulling the operation wire 43 near the affected area as shown in FIG. 16B, it is pulled into the inner sheath 41, and the crimping ring 2 moves accordingly, narrowing the opening of the clip 1X. When the operation wire 43 is further pulled, the crimping ring 2 moves toward the tip of the clip 1X, and the clip 1X closes and clamps the affected area. However, once the opening of the clip 1X is narrowed by the crimping ring 2, it is not possible to return the clip to its original opening even if one wishes to return it to its original position in order to correct the clamping position of the affected area. That is, even if the inner sheath 41 is pulled back as shown in FIG. 16C, the position of the crimping ring 2 in the clip 1X does not return to its original position, so the opening of the clip 1X remains narrow.

[0006] On the other hand, the clip described in Patent Document 3 and the like can be opened and closed again even after it has been closed once, so that the position of the affected area to be clamped by the clip can be corrected. However, a forceps-type instrument must be used to open and close this clip, and this clip cannot be opened and closed with an endoscopic clip device. In addition, this clip clamps a blood vessel or the like between the tip end and hinge of a pair of arms (legs), and maintains this state by engaging the hooks at the tips. However, when the affected area is clamped by the tips, the hooks at the tips cannot be engaged, so the clamped state of the affected area cannot be maintained. For this reason, this clip cannot be used for marking.

[0007] In contrast, the present invention aims to provide a medical clip that can be used with an endoscopic clipping device and can be used for both hemostasis and marking, and that allows the clip to be opened and closed again until it is completely closed. [Means for solving the problem]

[0008] The inventor discovered that for a leaf spring-like clip having opposing arms, if a hook-shaped protrusion is provided in the longitudinal center of one of the clip's arms and the other arm is latched by this hook-shaped protrusion, the tip of the clip can be used for both hemostasis and marking, and that crimping is no longer necessary, and the clip can be repeatedly opened and closed until the hook-shaped protrusion of one arm completely latches the other arm, and thus arrived at the present invention.

[0009] That is, the present invention provides a leaf spring-like medical clip having a first arm and a second arm opposed to each other, and a continuous portion where one end of the first arm is continuous with one end of the second arm, the first arm has a pair of hook-shaped projections at a center portion in a longitudinal direction thereof for latching the second arm from both sides; A medical clip is provided in which, when the first arm and the second arm approach each other to a predetermined distance, a pair of hook-shaped protrusions latch onto both sides of the second arm, thereby maintaining the first arm and the second arm in a close proximity. Effect of the Invention

[0010] According to the medical clip of the present invention, the tip of the clip is kept completely closed by the latch between the pair of hook-shaped projections at the longitudinal center of the first arm and the second arm, so that the tip of the clip can be used for both hemostasis and marking.

[0011] In addition, the first arm and the second arm can repeatedly open and close unless the hook-shaped protrusion of the first arm latches the second arm, which makes it easy to adjust the position where the clip clamps the affected area even after the clip is almost closed.

[0012] Moreover, this medical clip can be used by being attached to the inner sheath of an endoscopic clipping device. [Brief description of the drawings]

[0013] [Figure 1A]FIG. 1A is a perspective view of a clip 1A according to an embodiment in an open state, as viewed from its tip end side. [Figure 1B] FIG. 1B is a perspective view of the clip 1A of the embodiment in an open state, as viewed from its connecting portion side. [Figure 1C] FIG. 1C is a top view of the clip 1A of the embodiment in an open state. [Figure 1D] FIG. 1D is a side view of the clip 1A of the embodiment in an open state. [Diagram 2] FIG. 2 is a perspective view of the clip 1A of the embodiment in a latched state. [Figure 3A] FIG. 3A is a cross-sectional view illustrating a method of using the clip 1A of the embodiment. [Figure 3B] FIG. 3B is a cross-sectional view illustrating a method of using the clip 1A of the embodiment. [Figure 3C] FIG. 3C is a cross-sectional view illustrating a method of using the clip 1A of the embodiment. [Figure 3D] FIG. 3D is a cross-sectional view illustrating a method of using the clip 1A of the embodiment. [Figure 3E] FIG. 3E is a cross-sectional view illustrating a method of using the clip 1A of the embodiment. [Figure 4A] FIG. 4A is a cross-sectional view illustrating a method for clamping a mucous membrane with the clip 1A of the embodiment. [Figure 4B] FIG. 4B is a cross-sectional view illustrating a method of clamping a mucous membrane with the clip 1A of the embodiment. [Figure 4C] FIG. 4C is a cross-sectional view illustrating a method of clamping a mucous membrane with the clip 1A of the embodiment. [Figure 4D] FIG. 4D is a cross-sectional view illustrating a method for clamping a mucous membrane with the clip 1A of the embodiment. [Figure 5A] FIG. 5A is a perspective view of a clip 1B of the embodiment in an open state, as viewed from its tip end side. [Figure 5B] FIG. 5B is a perspective view of the clip 1B of the embodiment in an open state, as viewed from its connecting portion side. [Figure 6]FIG. 6 is a perspective view of the clip 1B of the embodiment in a latched state. [Figure 7A] FIG. 7A is a cross-sectional view illustrating a method of clamping a mucous membrane with a clip 1B of the embodiment. [Figure 7B] FIG. 7B is a cross-sectional view illustrating a method of clamping a mucous membrane with the clip 1B of the embodiment. [Figure 8A] FIG. 8A is a cross-sectional view illustrating a method of using the clip 1C of the embodiment. [Figure 8B] FIG. 8B is a cross-sectional view illustrating a method of using the clip 1C of the embodiment. [Figure 9] FIG. 9 is a side view of a modified embodiment of the clip 1A of the embodiment. [Figure 10] FIG. 10 is a side view of a clip 1A of the embodiment with a compression piece attached. [Figure 11] FIG. 11 is a top view of a clip 1A according to an embodiment to which a compression piece is attached. [Figure 12] FIG. 12 is a cross-sectional view of a state in which a mucous membrane is clamped by a clip 1A of the embodiment to which a compression piece is attached. [Figure 13] FIG. 13 is a perspective view of a clip 1D according to the embodiment. [Figure 14A] FIG. 14A is a perspective view of a clip 1D of the embodiment to which a compression piece is attached, as viewed from the tip end side. [Figure 14B] FIG. 14B is a perspective view of the clip 1D of the embodiment to which the compression pieces are attached, as viewed from the connecting portion side. [Figure 15] FIG. 15 is a cross-sectional view of a state in which a mucous membrane is clamped by a clip 1D of the embodiment to which a compression piece is attached. [Figure 16A] FIG. 16A is a cross-sectional view of a conventional medical clip 1X attached to an inner sheath. [Figure 16B] FIG. 16B is a cross-sectional view of the conventional medical clip 1X when it is slightly retracted into the inner sheath, resulting in a narrower opening of the clip. [Figure 16C]FIG. 16C is a cross-sectional view showing a state in which the conventional medical clip 1X is slightly pulled into the inner sheath and then the inner sheath is pulled back. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] The present invention will now be described in detail with reference to the drawings, in which the same reference numerals denote the same or equivalent components.

[0015] <Basic structure of medical clips> 1A and 1B are perspective views of a medical clip 1A according to an embodiment of the present invention in an open state, FIG. 1C is a top view thereof, and FIG. 1D is a side view thereof. Also, FIG. 2 is a perspective view of the medical clip 1A in a latched state.

[0016] This clip 1A is made of an elastic material such as a leaf spring, and has a first arm 10 and a second arm 20 facing each other, and a continuous portion 30 where one end of the first arm 10 and one end of the second arm 20 are curved and connected. The other ends of the first arm 10 and the second arm 20 are separated from each other, and the entirety is bent into a roughly "<" shape. In the present invention, the continuous portion 30 is not necessarily limited to a curved or bent portion that connects the first arm and the second arm, which is obtained by bending a strip of metal material. For example, as shown in Figures 4 and 7 of Japanese Patent No. 6694893, when the first arm and the second arm are formed from two leaf springs whose rear ends are bent into an L shape, the vicinity of their rear ends can be a portion that is connected by a reinforcing member.

[0017] In clip 1A of this embodiment, tip 11 of first arm 10 is bent towards second arm 20, and tip 21 of second arm 20 is bent towards first arm 10, with these tips having a triangular wave shape that fits together. Note that in the clip of the present invention, the shape of tips 11, 21 is not limited to this and may be trapezoidal, rectangular or the like, or may be unbent and formed so that these tips 11, 21 overlap each other when first arm 10 and second arm 20 are closed.

[0018] The clamping portion 15 adjacent to the tip 11 of the first arm 10 and the clamping portion 25 adjacent to the tip 21 of the second arm 20 each have an arm width wider than that of the continuous portion 30. Both side portions of the clamping portions 15, 25 stand inward, making it easier for the clamping portions 15, 25 to clamp biological tissue. Note that in the present invention, the shapes of the clamping portions 15, 25 can be appropriately changed depending on the application of the clip, etc.

[0019] (uncinate process) The first arm 10 has a pair of hook-shaped projections 12a, 12b at the center in the longitudinal direction, which can latch the second arm 20 from both sides of the second arm 20. More specifically, between the tip 11 of the first arm 10 and the continuous portion 30, the pair of hook-shaped projections 12a, 12b stand in the direction of the second arm portion 20 along both sides of the first arm 10, and the tips of the pair of hook-shaped projections 12a, 12b are bent in the direction facing each other. In the clip 1A of this embodiment, the hook-shaped projections 12a, 12b stand along both sides of the first arm 10, which makes it possible to easily manufacture the clip 1A by bending a metal plate. On the other hand, when the clip 1A is molded from resin, the hook-shaped projections 12a, 12b may stand from the inside of the first arm 10 rather than the side of the arm.

[0020] In this clip 1A, when the first arm 10 and the second arm 20 are pressed and brought into close proximity to each other by a predetermined distance, the pair of hook-shaped projections 12a, 12b latch the latched portion 22 of the second arm 20, as shown in Fig. 2. This latched portion 22 is flat, and once the hook-shaped projections 12a, 12b of the first arm 10 latch the latched portion 22 of the second arm 20, because the clip 1A is made of an elastic material, the second arm 20 is biased in a direction that increases the opening between the first arm 10 and the second arm 20, so that the latched state is stabilized and the close proximity state of the first arm 10 and the second arm 20 is maintained.

[0021] (Slope-shaped protrusion) Meanwhile, a sloped projection 23 extending in the longitudinal direction of the second arm 20 is provided on the outer surface 20o of the second arm 20 opposite the first arm 10, closer to the tip 21 than the latched portion 22 of the second arm 20. As shown in Fig. 1D, the height Hs of the sloped projection 23 relative to the outer surface 20o of the second arm 20 gradually increases toward the tip 21 of the second arm 20. For this reason, in a side view of the clip 1A, the sloped projection 23 has a triangular plate shape.

[0022] As described later, when clipping the clip 1A to the affected area using the clip sheath 40, the clip 1A is pulled toward the inner sheath 41, and the inner wall of the inner sheath 41 presses the first arm 10 and the second arm 20 closer to each other. If the sloped projection 23 is inclined as described above, the second arm 20 can be pressed efficiently. After the hook-shaped projections 12a, 12b of the first arm 10 latch the latched portion 22 of the second arm 20, the inner sheath 41 is pulled back to place the clip 1A on the affected area. If the sloped projection 23 is inclined as described above, the contact area between the clip 1A and the inner wall of the inner sheath 41 is reduced, and the frictional resistance between them is reduced. This makes it easy to pull back the inner sheath 41 while leaving the clip 1A on the affected area.

[0023] It is more preferable that the inclination angle α of the sloping projection 23 with respect to the outer surface 20o of the second arm 20 gradually increases toward the tip 21 of the second arm 20, that is, that the inclined surface of the sloping projection 23 has an R. Also, for the same reason, it is preferable that the width Ws of the sloping projection 23 in the short direction of the second arm 20 is narrow (FIG. 1C), and when the clip 1A is formed by bending a metal plate, it is preferable that the thickness of the sloping projection 23 is approximately the same as the thickness of the metal plate.

[0024] In this embodiment, two sloping protrusions 23 are formed along both the left and right sides of the second arm 20, but the manner in which the sloping protrusions 23 are formed is not limited to this. For example, one sloping protrusion may be formed on the center line A of the width of the second arm 20 in the short side direction.

[0025] (Inner sheath stopper) A protrusion 13 is provided as an inner sheath stopper on the outer surface 10o of the first arm 10 opposite the second arm 20, closer to the tip 11 of the first arm than the pair of hook-shaped projections 12a, 12b. As will be described later, when clip 1A attached to clip sheath 40 is pulled toward the inner sheath 41 by the operating wire 43 to bring the first arm 10 and the second arm 20 closer to each other, it is preferable that the inner sheath stopper 13 is provided because the open end face of the inner sheath 41 abuts against the inner sheath stopper 13 and the clip 1A is not unnecessarily pulled into the inner sheath 41.

[0026] 2, in a state in which the hook-shaped projections 12a, 12b of the first arm 10 latch the second arm 20, the position of the continuous portion side end 13a of the inner sheath stopper 13 in the clip longitudinal direction is preferably within the range in which the slope-shaped projection 23 in the clip longitudinal direction is formed in the same state. This makes it possible to keep the length by which the clip 1A is retracted into the inner sheath 41 to a necessary minimum when the clip 1A attached to the clip sheath 40 is retracted toward the inner sheath 41 to bring the first arm 10 and the second arm 20 closer to each other.

[0027] (Bending part of the first arm and bending part of the second arm) The first arm 10 has a first arm curved portion 14 curved convexly toward the second arm 20 between the hook-shaped projections 12a, 12b and the continuous portion 30. On the other hand, the second arm 20 has a second arm curved portion 24 curved convexly toward the first arm 10 between the latched portion 22 and the continuous portion 30.

[0028] The first arm curved portion 14 and the second arm curved portion 24 come into contact with each other when the clip 1A is retracted into the inner sheath 41 to close the clip 1A, and serve as a fulcrum for opening and closing the first arm 10 and the second arm 20. As the amount of retraction of the clip 1A in the inner sheath 41 increases and the opening between the first arm 10 and the second arm 20 decreases, the abutting point between the first arm curved portion 14 and the second arm curved portion 24 moves toward the tip 11 of the first arm and the tip 21 of the second arm. This increases the force with which the clip 1A is closed to clamp the biological tissue with the clamping portions 15 and 25, and also disperses the stress applied to the clip 1A when the clip 1A is closed. Therefore, even if the clip 1A is made of resin, it is possible to prevent the arms 10 and 20 from breaking when the clip 1A is opened and closed.

[0029] (Width of first and second arms) The width W2 (length in a direction perpendicular to the longitudinal direction of the second arm 20) of the second arm 20 in the top view of the clip 1A (FIG. 1C) is narrowest at the continuous portion 30 and the second arm curved portion 24, and is wider at the latched portion 22 and the portion where the slope-shaped projection 23 is formed. The tip portion 21 and the clamping portion 25 that directly clip the affected area are even wider, and only need to be accommodated in the outer sheath 42 of the clip sheath 40. Similarly, the width W1 of the first arm 10 is wider at the portion where the hook-shaped projections 12a, 12b are formed than the continuous portion 30 and the first arm curved portion 14, and further the tip portion 11 and the clamping portion 15 are wider than the portion where the hook-shaped projections 12a, 12b are formed.

[0030] (forming material) The clip 1A can be easily and inexpensively manufactured by bending a metal plate that will serve as a leaf spring, such as stainless steel. The clip 1A may be made of a resin such as polycarbonate or ABS that exhibits high rigidity similar to the resin described in Patent Document 2, or a heat-resistant thermoplastic resin such as PEEK (polyether ether ketone) may be used. The material is appropriately selected depending on the application of the clip.

[0031] The resin preferably has a flexural modulus (JIS K 7171) of 2000 MPa or more and a flexural strength (JIS K 7171) of 90 MPa or more. Polycarbonate, ABS, etc. are preferred because of their excellent resistance to acid and alkali against digestive fluids.

[0032] When clip 1A is made of resin, it is preferable to increase the amount of resin in continuous portion 30 in order to increase the elasticity of clip 1A having a "<" shape.

[0033] In addition, when the clip 1A is used as a marker, it is preferable that the resin forming the clip 1A contains a fluorescent dye. The fluorescent dye is preferably one that emits fluorescence in the wavelength range of red light to near-infrared light of 600 to 1400 nm, preferably in the wavelength range of red light to near-infrared light of 700 to 1100 nm. Light in such a wavelength range is highly permeable to human tissues such as skin, fat, and muscle, and can easily reach, for example, the mucous membrane to the serosal surface of tubular human tissues such as the rectum.

[0034] Examples of fluorescent dyes that emit fluorescence in the above-mentioned wavelength ranges include riboflavin, thiamine, NADH (nicotinamide adenine dinucleotide), indocyanine green (ICG), an azo-boron complex compound described in JP 2011-162445 A, a dye having a condensed ring structure described in WO 2016 / 132596 A, a dye having a boron dipyrromethene skeleton described in JP 5177427 A, a dye that chemically bonds to silica particles described in JP 2020-74905 A, and a phthalocyanine dye described in JP 2020-105170 A.

[0035] A preferred concentration of the fluorescent dye in the resin can be set depending on the type of the fluorescent dye and the resin, and is usually preferably 0.001 to 1% by mass.

[0036] In order to make the resin contain the fluorescent dye, for example, a twin-screw kneader is used to knead the fluorescent dye into the resin, and then the clip body is formed by injection molding.

[0037] (How to use) When the clip 1A is used as an endoscopic clip, the clip 1A is attached to a clip sheath 40 of an endoscopic clip device, as shown in FIG. 3A. The clip sheath 40 may be one having an inner sheath 41, an outer sheath 42, and an operating wire 43, as described in Japanese Patent No. 4388324, Japanese Patent No. 5045484, etc., or a commercially available one. The clip 1A may be attached to the clip sheath 40 by, for example, hooking a connecting portion 44 of the operating wire 43 to an end of the continuous portion 30 of the clip 1A. Alternatively, a connecting hook may be used as described in Japanese Patent No. 5781347, etc.

[0038] When the clip 1A is pulled into the outer sheath 42 by the operating wire 43 by operating the endoscopic clipping device, the clip 1A closes as shown in Fig. 3B, and when the clip 1A is protruded from the outer sheath 42, the tip portions 11, 21 of the clip 1A open again as shown in Fig. 3A. When the clip 1A is pulled into the inner sheath 41 as shown in Fig. 3C, the tip portions 11, 21 of the clip 1A gradually close, and when the inner sheath 41 hits the continuous portion side end portion 13a of the inner sheath stopper 13 and hits the slope of the slope-shaped projection 23 as shown in Fig. 3D, the hook-shaped projections 12a, 12b of the first arm 10 latch the second arm 20. The clip 1A cannot be pulled further into the inner sheath 41. Next, by pulling back the inner sheath 41, the clip 1A in a state in which the first arm 10 and the second arm 20 are latched by the hook-shaped projections 12a, 12b can be removed from the clip sheath 40 as shown in FIG. 3E.

[0039] To explain the case where clip 1A is used to clamp, for example, an affected area of ​​the mucosa of a hollow organ, clip 1A is attached to operating wire 43, and clip 1A is retracted into outer sheath 42 by operating wire 43 as shown in Fig. 3B, and in this state clip sheath 40 is inserted into the inside of the hollow organ. The endoscopic clipping device is operated to project clip 1A from outer sheath 42 as shown in Fig. 4A, and tip portions 11, 21 of clip 1A are opened near the affected area of ​​mucosa X. Then, clip 1A is brought into contact with mucosa X as shown in Fig. 4B, and clip 1A is retracted into inner sheath 41, thereby closing tip portions 11, 21 of clip 1A. As shown in FIG. 4B, even if the tip portions 11, 21 of clip 1A begin to grasp mucosa X, as long as the hook-shaped protrusions 12a, 12b of the first arm 10 have not latched the second arm 20, the tip portions 11, 21 of clip 1A can be opened again by pulling back the inner sheath 41, so that the position of the mucosa clipped by the tip portions 11, 21 of clip 1A can be corrected as necessary.

[0040] When the distal end 11, 21 of the clip 1A grasps the mucosa X at the desired position, the hook-shaped projections 12a, 12b of the first arm 10 latch the second arm 20, and the distal end 11, 21 of the clip 1A clamps the mucosa X, as shown in FIG. 4C. At this time, the inner sheath 41 abuts on the end 13a of the inner sheath stopper 13 at the continuous part side and on the slope of the slope-shaped projection 23. Therefore, the sliding resistance between the inner sheath 41 and the clip 1A is low when the inner sheath 41 is pulled back. Therefore, as shown in FIG. 4D, the connecting portion 44 of the operating wire 43 is removed from the continuous part 30 of the clip 1A, and the inner sheath 41 and the outer sheath 42 are pulled back, so that the clip 1A clamping the mucosa X can be placed on the mucosa of the tubular organ.

[0041] (Transformation mode) The medical clip of the present invention can take various forms. For example, in the above-mentioned clip 1A, the inner sheath stopper 13 is formed on the first arm 10 having the hook-shaped projections 12a and 12b, and the sloped projection 23 is formed on the second arm 20 having the latched portion 22. However, the sloped projection 23 may be formed on the first arm 10 having the hook-shaped projections 12a and 12b, and the inner sheath stopper 13 may be formed on the second arm 20 having the latched portion 22.

[0042] In addition, in the present invention, the slope-shaped projection 23 and the inner sheath stopper 13 may be omitted. For example, the clip 1B shown in Fig. 5A, Fig. 5B, and Fig. 6 is common to the above-mentioned clip 1A in that the first arm 10 has hook-shaped projections 12a and 12b, and the hook-shaped projections 12a and 12b latch the second arm 20 to hold the tip 11 of the first arm 10 and the tip 21 of the second arm 20 in a closed state. However, in this clip 1B, the latched portion 22 is recessed toward the first arm 10 in a well-shaped manner. By recessing the latched portion 22 of the second arm 20 toward the first arm 10 in this manner, when the clip 1B is attached to the clip sheath 40 of the endoscopic clip device and the clip 1B is pulled into the inner sheath 41 by the operating wire 43, the hook-shaped projections 12a and 12b of the first arm 10 can be latched to the second arm 20 with a smaller amount of pulling.

[0043] In addition, in this clip 1B, the second arm 20 is not formed with a slope-shaped projection, and the first arm 10 is not formed with an inner sheath stopper 13.

[0044] For this reason, when clip 1B is attached to clip sheath 40 of an endoscopic clipping device as shown in FIG. 7A and clip 1B is pulled into inner sheath 41 with operating wire 43, convex portion 26 adjacent to the recess in latched portion 22 on the continuous portion 30 side of the recess comes into contact with the inner wall of inner sheath 41 as shown in FIG. 7B, causing tip portions 11, 21 of clip 1B to close.

[0045] After the clip 1B is closed in this manner, when the clip 1B is to be removed from the clip sheath 40, the inner sheath 41 is pulled back in the same manner as the above-described clip 1A, and the operating wire 43 is removed from the clip 1B.

[0046] When inner sheath 41 of clip 1B is pulled back, convex portion 26 of second arm 20 and outer surface 10o of first arm 10 slide against the inner wall of inner sheath 41. For this reason, the surface of clip 1B preferably has low sliding resistance.

[0047] 8A and 8B , in order to reduce the area of ​​contact between the clip and the inner wall of the inner sheath 41 and thereby lower the sliding resistance, hemispherical protrusions 17, 27 may be provided at a portion adjacent to protrusion 26 on the continuous portion 30 side of protrusion 26 of second arm 20 and at a corresponding portion of first arm 10. Hemispherical protrusions 17, 27 come into point contact with the inner wall of the inner sheath 41, and therefore the sliding resistance between clip 1C and the inner wall of the inner sheath 41 can be reduced.

[0048] In addition, in each of the above-mentioned clips, when using a connecting portion 45 of the operating wire 43 having a tip bent into a hook shape as shown in Figure 9, and the hook-shaped portion is hooked onto the continuous portion 30 of the clip, a protrusion 31 may be provided on the continuous portion 30 to prevent the tip of the operating wire 43 from moving unnecessarily toward the tip portions 11 and 21 of the clips 1A, 1B and 1C.

[0049] As shown in Fig. 10, for example, a compression piece 50 made of flexible resin and holding a fluorescent dye may be attached to the clamping portion 15, 25 of each clip described above, and the compression piece 50 may be made to protrude from the distal end portion 11, 21 of the arm. Fig. 11 is a top view of a clip 1A having a compression piece 50. Fig. 12 is a cross-sectional view of the state in which the mucosa is clamped by the clip 1A with the compression piece 50.

[0050] The flexible resin forming the compression piece 50 is preferably one that does not denature even if left in the digestive tract for a long period of time and has acid resistance to stomach acid. Examples of such flexible resins include resins used in medical devices, such as soft polyvinyl chloride, thermoplastic polyurethane, silicone, and ethylene-vinyl acetate copolymer.

[0051] In addition, it is preferable that the compression piece 50 has a suitable hardness and elasticity so that when the clip 1A is clamping the biological tissue, the compression piece 50 bends and the protruding portion 51 can effectively compress the biological tissue.

[0052] The hardness of the compression piece 50 is preferably in the range of A10 to A90 as Shore A (JIS K 6253) or D40 to D70 as Shore D (JIS K 6253) measured with a durometer. The hardness of the compression piece 50 is preferably selected appropriately depending on the shape, size, etc. of the compression piece 50.

[0053] The elasticity of the compression piece 50 is preferably in the range of 4 to 200 MPa in bending elasticity (ASTM D 790), and more preferably in the range of 10 to 100 MPa.

[0054] The fluorescent dye to be retained in the compression piece 50 is preferably one that emits fluorescence in the red light to near-infrared light wavelength range of 600 to 1400 nm, preferably in the red light to near-infrared light wavelength range of 700 to 1100 nm, and the above-mentioned ones can be used.

[0055] As a specific embodiment for retaining the fluorescent dye in the compression piece 50, the fluorescent dye may be contained in the flexible resin forming the compression piece 50, or a coating film containing the fluorescent dye may be formed on the surface of the compression piece formed of a flexible resin. When the fluorescent dye is contained in the flexible resin forming the compression piece 50, a preferable concentration of the fluorescent dye can be set according to the type of the fluorescent dye and the resin, and is usually preferably 0.001 to 1% by mass.

[0056] On the other hand, the shape of the compression piece 50 is roughly rectangular, and in each of the first arm 10 and the second arm 20, the compression piece 50 protrudes from the clamping portion 15, 25 in the longitudinal direction of the arm. The compression piece 50 can be provided with constrictions 52, 53 on the inner and outer sides in the longitudinal direction of the arm near the tip end 11, 21 of each arm. This makes it easier for the protruding portion 51 of the compression piece 50 to bend as shown by the dashed line in Fig. 10. Depending on the size, shape, and presence or absence of the constrictions 52, 53, the force with which the compression piece 50 presses the biological tissue when the biological tissue is clamped by the clip 1A with the compression piece 50 can be adjusted.

[0057] As shown in FIG. 12, when the biological tissue X is clamped by the clip 1A with the compression piece 50, the compression piece 50 is bent, and the bent part strongly presses the biological tissue X in the thickness direction of the biological tissue, and blood in the vascular network Y of the submucosa is expelled. In this state, when the compression piece 50 is irradiated with excitation light in the red to near-infrared wavelength range as excitation light from the serosal membrane side, the excitation light is absorbed by the fluorescent dye held by the compression piece 50 without being absorbed and inhibited by hemoglobin, and the fluorescent dye emits fluorescence in the red to near-infrared wavelength range. This fluorescence is emitted to the outside of the tubular organ without being absorbed and inhibited by hemoglobin. Therefore, this fluorescence can be observed well from the outside of the tubular organ, and the position of the biological compression clip clamped inside the tubular organ can be known, and the position of the affected area can be specified.

[0058] When providing a compression piece 50 to a clip, the area from the tip 11, 21 of each arm 10, 20 to the clamping portion 15, 25 may be formed in a comb shape as in clip 1D shown in Fig. 13. Figs. 14A and 14B are perspective views of clip 1D in which compression pieces 50 are provided by insert molding in clamping portions 15, 25.

[0059] That is, in this clip 1D, two comb teeth 11t, 21t are arranged in parallel from the tip 11, 21 of each arm 10, 20 to the clamping portion 15, 25, and a comb tooth space 11s, 21s is formed between the two comb teeth. In addition, in the clamping portion 15, 25 of each arm 10, 20, a hole portion 18, 28 for reliably fixing the compression piece 50 is provided as necessary in a portion closer to the continuous portion 30 than the comb teeth 11t, 21t. In addition, in the clip 1D of this embodiment, two comb teeth 11t, 21t are provided in each arm 10, 20, but in the present invention, the number of teeth of the comb teeth in each arm 10, 20 is not limited to this, and may be two or more, and is preferably two to three.

[0060] In addition, the claws 11a, 21a standing inward at the tips of the comb teeth 11t, 21t are preferably formed so that the claws 11a, 21a are spaced apart from the central axis L of the clip 1D when the clip 1D is closed. Here, in the present invention, the central axis L of the clip is an axis that bisects the width W of the arm in the top view of the clip (FIG. 11) and is equidistant from the pair of arms 10, 20 in the side view of the clip (FIG. 12). When the clip 1D is closed, the claws 11a, 21a of the tips 11, 21 are spaced apart from the central axis L, so that when the clip 1D clamps the mucous membrane of a living tissue as shown in the cross-sectional view of FIG. 15, the fluorescence emitted not only by the protruding part 51 and the outer part 54 of the compression piece 50 but also by the inner part 55 and the part between the comb teeth 56 is emitted toward the serous membrane without being blocked by the metal plates and claws 11a, 21a that constitute the arms 10, 20. Therefore, the intensity of the fluorescent light in the observation direction can be significantly increased.

[0061] In addition, the clip 1D having the compression piece 50 can be easily manufactured by insert molding, and even when a separately molded compression piece is attached to the clamping portions 15, 25 of the arms 10, 20 with adhesive, the compression piece 50 can be easily and firmly attached by fitting the compression piece into the inter-tooth spaces 11s, 21s. The various modifications described above can be combined as appropriate. [Explanation of symbols]

[0062] 1A, 1B, 1C, 1D Clips 1X Clip 2. Crimping 10 First Arm 10o Outer surface of first arm 11 Tip 11a Claw 11t comb teeth 11s Space between teeth 12a, 12b Hook-shaped protrusion (latch portion) 13 Inner sheath stopper, protruding part 13a: End of the inner sheath stopper on the continuous side 14 First arm curved section 15 Clamping part 16 Operation convex part 17 Hemispherical convex part 18 Hole 20 Second Arm 20o Outer surface of second arm 21 Tip 21a Claw 21t comb teeth 21s Teeth Space 22 Latched part 23 Slope-shaped protrusion 24 Second arm curved section 25 Clamping part 26 Convex 27 Hemispherical convex part 28 Hole 30 Continuous section 31 Protrusion 40 Clip sheath 41 Inner sheath 42 Outer sheath 43 Control wire 44 Connecting part 45 Connecting part 50 Compression Pads 51 Protruding part 52 Waist 53 Waist 54 Outer part 55 Inner part 56 Between the comb teeth 57 Reinforcement part A Center line of the width of the second arm in the short direction Hs Height of the sloped protrusion L Clip center axis W, W1, W2 Arm width, 1st arm width, 2nd arm width Ws Width of sloped protrusion X Mucous membrane, living tissue Y vascular network α Slope angle of the slope

Claims

1. A leaf spring-like medical clip having a first arm and a second arm opposed to each other, and a continuous portion between one end of the first arm and one end of the second arm, The first arm has a pair of hook-shaped projections at the longitudinal center thereof for latching both sides of the second arm, the first arm has a first arm curved portion between the hook-shaped projections and the continuous portion, the first arm curved portion being curved in an arc from the flat portion of the first arm toward the second arm, and the second arm has a second arm curved portion between the latched portion and the continuous portion, the second arm curved portion being curved in an arc from the flat portion of the second arm toward the first arm, When the clip is in an open state, the end portion of the first arm curved portion on the side of the continuous portion comes into contact with the end portion of the second arm curved portion on the side of the continuous portion, and the contact point serves as a fulcrum for opening and closing the first arm and the second arm, and as the opening between the first arm and the second arm becomes smaller, the contact point moves toward the tip end of the first arm and the second arm, When the first arm and the second arm approach each other by a predetermined distance, the pair of hook-shaped projections latch both sides of the second arm, thereby maintaining the first arm and the second arm in a state of close proximity. Medical clip.

2. 2. The medical clip according to claim 1, which is made of resin.

3. 2. The medical clip according to claim 1, which is made of metal.

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