JP2006175051A - Overtube for endoscope - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an overtube for an endoscope capable of guiding the insertion of an endoscope with the shape of a subject retained. <P>SOLUTION: This overtube for the endoscope is provided with: a flexible tube part 11 having a conduit for inserting the endoscope and passively deformed in response to the deformation of the inserted endoscope; a plurality of piece members 15 incorporated and arranged along the conduit of the flexible tube part axially overlapping mutually and coming into slide contact with one another; and abutment faces 32a of step parts 33 provided in respective sliding ends of the plurality of piece members 15 as the abutment parts provided in the sliding ends of the piece members 15 for retaining the positions of the piece members, when the plurality of piece members 15 come into slide contact with one another, slide a predetermined angle or more and abut on one another. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an endoscope overtube which is an endoscope insertion aid used when an insertion portion of an endoscope is inserted.

  In general, an endoscope that is inserted into a body cavity to be inspected and treated has an elongated insertion section that is inserted into the body cavity and an operation section provided on the proximal side of the proximal end of the insertion section. Are connected and formed. The insertion portion is configured by sequentially connecting a distal end portion, a bending portion, and a flexible flexible portion from the distal end side.

  The operation of inserting the endoscope into the body cavity will be described with reference to FIGS. 10 and 11 by taking colonoscopy as an example. FIG. 10 is an explanatory view showing the state of the endoscope at the time of colonoscopy, and FIG. 11 is a conventional endoscope over assisting insertion of this endoscope with respect to the endoscope of FIG. It is explanatory drawing which shows the mode of a tube. 10 and 11, reference numeral 90 is an anus, reference numeral 91 is a rectum, reference numeral 92 is a sigmoid colon, reference numeral 93 is a descending colon, reference numeral 94 is a splenic curved portion 94, Reference numeral 95 is the transverse colon, reference numeral 96 is the liver curvature, reference numeral 97 is the ascending colon, and reference numeral 98 is the cecum.

The surgeon inserts the distal end portion 52 of the endoscope insertion portion 51 from the anus 90 and flexibly moves from the rectum 91 to the sigmoid colon 92, the descending colon 93, and the splenic bending portion 94 while operating the bending portion 53 to bend. The hand 54 side is inserted while being pushed in. The surgeon inserts the distal end portion 52 of the endoscope insertion portion 51 that has passed through the sigmoid colon 92 into the splenic curved portion 94 as shown in FIG. The flexible part 54 curved in a letter shape is pushed in from the hand side.
Then, the insertion force of the endoscope insertion portion 51 is not transmitted to the distal end portion 52, and the portion curved in an S shape is further curved in an S shape, and the flexible portion 54 is formed on the wall surface of the sigmoid colon 92. A so-called sticking phenomenon occurs that pushes the lens into the deep part of the large intestine.

Therefore, in general, a sliding tube or an overtube (hereinafter simply referred to as an overtube) 100 as an insertion aid is attached to the insertion portion 51 in advance, and insertion into the large intestine is performed. As shown in FIG. 11, when the flexible portion 54 of the endoscope insertion portion 51 is inserted from the rectum 91 through the sigmoid colon 92 to the vicinity of the descending colon 93, the overtube 100 moves the flexible portion 54. Straighten and straighten the sigmoid colon 92 (shorten the sigmoid colon 92 to fold).
Then, the surgeon inserts the overtube 100 from the anus 90 through the rectum 91 into the sigmoid colon 92 along the linearized flexible portion 54 so that the linear state of the sigmoid colon 92 is achieved. I try to keep it. Thereby, the overtube 100 facilitates an insertion operation into the deep part of the large intestine after the descending colon 93.

  As described above, the overtube 100 is relatively flexible, and is used when the endoscope insertion portion 51 is inserted into a subject site having a complicated curved shape. It is formed to be harder than the portion 54. That is, the overtube 100 has a rigidity for maintaining the sigmoid colon 92 in a straight state so that the pushing force of the endoscope insertion portion 51 is sufficiently transmitted to the distal end portion 52. For this reason, the subject may feel pain when the overtube 100 is inserted.

On the other hand, for such an overtube 100, for example, Patent Document 1 proposes an overtube that avoids pain that may be given to a subject during insertion. The overtube proposed in Patent Document 1 is configured to be relatively soft when inserted into a subject and to be rigid after being inserted into the sigmoid colon 92 and straightening the sigmoid colon 92. ing.
The overtube described in Patent Document 1 includes an auxiliary tool flexible tube portion and an auxiliary tool operation portion provided at the base of the flexible tube portion. The flexible tube portion includes an inner tube and an outer tube. The inner side of the inner tube is a hollow part through which the endoscope insertion part is inserted.

  Between the inner tube and the outer tube, a cylindrical coil formed by winding a steel wire is provided in the longitudinal direction of the flexible tube portion. This coil has a straight cylindrical shape that is substantially concentric with the flexible tube portion in a free state. The tips of four coil pulling wires arranged at equal intervals in the circumferential direction are fixed to the tips of the coils. This coil pulling wire is extended to the operation part along the outer peripheral surface of the coil, and the base end is connected to the flexible adjustment dial provided in the operation part. This flexible adjustment dial pulls or relaxes the coil puller wire.

That is, the overtube proposed in Patent Document 1 is such that when the coil puller wire is relaxed by the flexibility adjustment dial, the coil becomes free, the flexible tube portion becomes soft, and the coil puller wire is pulled. The coil is compressed to increase the bending rigidity and become difficult to bend, and the flexible tube portion is cured. As a result, the overtube proposed in Patent Document 1 is inserted into the subject along the endoscope insertion portion by loosening the coil puller wire and inserting the flexible tube portion into a flexible state. After the insertion to a predetermined site, the coil puller wire is pulled to harden the flexible tube portion, thereby maintaining the subject site in a straight line.
JP 2002-369971 A (refer to pages 3 to 5 of the specification, FIGS. 1 to 4).

  The overtube, which is an endoscope insertion aid proposed in Patent Document 1, relaxes the coil puller wire when inserted into the subject along the endoscope insertion portion inserted into the subject. In addition, since the coil built in the flexible tube portion is in a free state and the flexible tube portion is in a soft state, the possibility of causing pain to the subject is reduced. Furthermore, the overtube described in the above-mentioned Patent Document 1 is formed by pulling a coil pulling wire after being inserted into a predetermined part of a subject to compress the coil and curing the flexible tube portion to make it linear. The insertion force of the endoscope insertion portion can be sufficiently transmitted to the distal end portion, and subsequent insertion operations are facilitated.

  However, the overtube described in Patent Document 1 is inserted into a desired position of the subject and deformed into a shape different from the original shape of the subject. For example, the overtube described in Patent Document 1 is operated in a flexible state when inserted into the sigmoid colon, and is cured linearly after insertion into the sigmoid colon to deform the sigmoid colon. At this time, the relatively soft sigmoid colon is less painful. In addition, the overtube described in Patent Document 1 has no pain caused by deforming the original shape of the subject, and there is a possibility that the shape may be adversely affected by changing the shape.

Therefore, there is a need for an overtube for an endoscope that can insert and guide the insertion portion of the endoscope without changing the shape of the examination site of the subject.
The present invention has been made in view of such circumstances, and an object thereof is to provide an endoscope overtube capable of guiding and inserting an endoscope insertion portion while maintaining the shape of a subject. .

  An endoscope overtube according to the present invention includes a flexible tubular portion having a conduit through which an endoscope can be inserted and passively deforming in response to a shape change of the inserted endoscope. A plurality of coma members arranged in a sliding contact with each other in the axial direction along the conduit of the flexible tubular part, and the plurality of coma members are in sliding contact with each other to be at a predetermined angle or more When sliding, the top members are abutted against each other, and have a butting portion provided at the sliding end of the top member for holding the position.

  The endoscope overtube of the present invention has an effect that the endoscope insertion portion can be guided and inserted while maintaining the shape of the subject.

  Embodiments of the present invention will be described below with reference to the drawings.

  1 to 6 relate to Embodiment 1 of the present invention, FIG. 1 is an overall configuration diagram showing an endoscope overtube of Embodiment 1, and FIG. 2 is a cross-sectional view of the endoscope overtube of FIG. 3 is an explanatory view showing a state in which generally assumed top members are in sliding contact with each other, FIG. 4 is a perspective view showing the top member of the present invention, and FIG. 5 is a view in which the top members in FIG. FIG. 6 is a perspective view of a piece member showing a modification of FIG. 4.

  As shown in FIGS. 1 and 2, the endoscope overtube 10 according to the first embodiment of the present invention has a flexible tubular portion 11 having a tubular shape as a whole and a proximal end of the flexible tubular portion 11. And an operation unit 12 provided in the configuration. In the axial direction of the flexible tubular portion 11 and the operation portion 12, a conduit 13a that is a hollow portion through which an endoscope insertion portion (not shown) is inserted is provided.

The flexible tubular portion 11 includes an inner tube 13 having a predetermined length in the longitudinal direction, and an outer tube 14 provided on the outer periphery of the inner tube 13. The outer peripheral surface of the distal end of the inner tube 13 and the inner peripheral surface of the distal end of the outer tube 14 are firmly fixed.
The inner tube 13 and the outer tube 14 on the proximal end side from the distal end positions that are closely fixed to each other are provided with a predetermined interval, and the proximal end side is held and fixed to the operation unit 12 at a predetermined interval. .

  The inner periphery of the inner tube 13 is a conduit 13a through which an endoscope insertion portion (not shown) is inserted. The inner tube 13 having the pipe line 13 a is fixed in a through-hole having the same diameter formed in the operation unit 12. A plurality of top members 15 are arranged between the inner tube 13 and the outer tube 14 in the axial direction of the flexible tubular portion 11. A mesh tube 16 formed in a cylindrical shape by a mesh member is disposed in the axial direction of the flexible tubular portion 11 on the outer peripheral side of the plurality of top members 15 and the inside of the outer tube 14.

  The top member 15 is slidable with the outer periphery of the inner tube 13, and is normally slidable between the front and back top members 15. The mesh tube 16 freely slides and contacts the outer peripheral surface of the top member 15 to form a straight tube shape substantially concentric with the flexible tubular portion 11. Further, the tip of the mesh tube 16 is attached and fixed to the most distal piece of the plurality of piece members 15 by a fixture 16 a. Note that a puller wire (not shown) may be used instead of the mesh tube 16.

  The operation portion 12 is formed in a substantially cylindrical shape, and has a large-diameter gripping portion 17 that the operator grips when using the overtube 10, and an outer periphery on the proximal end side of the inner tube 13 that extends from the gripping portion 17. Is fixed to the interior, and the frame fixing cylinder portion 18 to which the frame member 15 on the most proximal side among the plurality of frame members 15 is attached and fixed, and the outer tube 14 provided on the outer peripheral side of the frame fixing cylinder portion 18. And an outer tube fixing cylinder portion 23 to which the base end is attached and fixed.

The frame fixing cylinder 18 has an inner diameter that allows the outer diameter of the inner tube 13 to be fixed tightly. The outer tube fixing cylinder portion 23 is formed to have a larger diameter than the frame fixing cylinder portion 18 and holds the space 20 between the inner tube 13 and the outer tube 14.
In the space 20 between the frame fixing cylinder portion 18 and the outer tube fixing cylinder portion 23, a ring-shaped fixing ring 22 to which the proximal end of the mesh tube 16 is attached and fixed is slidably provided. The fixed ring 22 slides in the longitudinal direction of the operation portion 12 to pull or loosen the mesh tube 16, thereby applying a pressing force to each of the top members 15 to maintain the sliding contact state before and after the top member 15. It is made to slide by the shape holding part 19 mentioned later.

  This shape holding part 19 is provided in the longitudinal direction of the pin 25 and the outer tube fixing cylinder part 23 which are planted at a predetermined interval in a ring-shaped fixing ring 22 to which the proximal end of the mesh tube 16 is fixed. A guide groove 24 into which a pin 25 is fitted and slidably guided, and a pin 25 which is rotatably provided on the outer periphery of the outer tube fixing cylinder portion 23 and protrudes from the guide groove 24 of the outer tube fixing cylinder portion 23 is provided. And a cam member 26 having a cam groove 27 that is slidably driven in the longitudinal direction.

  Next, the shape of the piece member 15 will be described. Here, the piece member 15 is considered as shown in FIG. As shown in FIG. 3, the top member 15 includes a cylindrical body 30 that is hollow by a relatively long thickness by a relatively thick member, a convex spherical surface 15 b that is formed on the thick portion of the front end surface of the cylindrical body 30, and a cylindrical body. 30 and a concave spherical surface 15c formed in the thick part of the rear end face.

The convex spherical surface 15 b is formed in a convex shape having a radius R in the axial direction from the outer periphery to the inner periphery of the thick member of the cylindrical body 30. On the other hand, the concave spherical surface 15 c is formed in a concave shape having a radius R in the axial direction from the outer periphery to the inner periphery of the thick member of the cylindrical body 30. The convex spherical surface 15b and the concave spherical surface 15c are formed with the same curvature.
The top member 15 having such a shape is inserted into the hollow of the cylindrical body 30 on the outer peripheral side of the inner tube 13 from the convex spherical surface 15b on the front end surface to the concave spherical surface 15c on the rear end surface, and is inserted first. The convex spherical surface 15b of the front end surface of the next piece member 15 is inserted in a contact state into the concave spherical surface 15c of the rear end surface.

  In this manner, the top member 15 is sequentially inserted and disposed on the outer periphery of the inner tube 13 in such a manner that the concave spherical surface 15c on the rear end surface of the one top member 15 and the convex spherical surface 15b on the front end surface of the other top member 15 are in contact. . In the overtube 10, a plurality of piece members 15 are arranged in a straight tube shape on the outer periphery of the inner tube 13, and a mesh tube 16 is arranged on the outer periphery of the piece member 15.

  In the configuration of the top member 15 as described above, when the overtube 10 is inserted along the body cavity duct, the flexible tubular portion 11 becomes soft when the mesh tube 16 is in a relaxed state, and the flexible tubular portion 11 becomes flexible. The portion 11 is curved and deformed. Then, in the top member 15, the convex spherical surface 15ba and the concave spherical surface 15c freely slide according to the curved deformation of the flexible tubular portion 11. That is, when the inner tube 13 is bent and deformed, the convex spherical surface 15b and the concave spherical surface 15c of each piece member 15 slide, and the sliding contact positions of the front and rear piece members 15 can be displaced.

  In this sliding contact state, the top members 15 are pulled by the mesh tube 16, whereby the frictional resistance between the convex spherical surface 15b and the concave spherical surface 15c of each piece member 15 is increased, and the frictional force in the axial direction ( (The pressing force) is sequentially transmitted to the top members 15, the top members 15 are compressed, and the sliding contact positions of the top members 15 are maintained.

  That is, the flexible tubular portion 11 of the overtube 10 that is passively deformed and inserted by the endoscope insertion portion that is inserted according to the shape of the subject while the mesh tube 16 is relaxed is flexible. The compressive force (pressing force) is applied to the sliding surfaces one after another by increasing the sliding frictional resistance between the top members 15 by applying an axial traction force to the top members 15 built in the tubular member 11. The deformed shape of the flexible tubular portion 11 can be maintained by the transmission and compression of the top members 15. That is, the convex surface 15b and the concave spherical surface 15c of each piece member 15 constitute a pressing force transmission surface.

  The above-mentioned piece member 15 maintains the desired shape maintaining function by dropping the piece and preventing the spherical contact with the entire circumference when the piece members 15 slide over a predetermined angle due to the bending of the flexible tubular portion 11. It may be difficult to do so. Therefore, it is necessary to configure the top member 15 so that a desired shape maintaining function can be maintained.

In the present embodiment, when the piece members 15 slide over a predetermined angle, the pressing force transmitted from the shape holding part 19 while holding the position without dropping the piece is applied to the convex spherical surface of one cylindrical body 31. 15 b can be transmitted to the concave spherical surface 15 c of the other cylindrical body 31.
That is, as shown in FIGS. 4 and 5, the top member 15 of the present embodiment is provided with a stepped portion 32 over the entire circumference at the sliding end of the convex spherical surface 15 b of the cylindrical body 31, and the stepped portion 32 abuts. The surface 32a is used as the butting portion.

As a result, when the concave spherical surface 15c of the other cylindrical body 31 slides by a predetermined angle with respect to the convex spherical surface 15b of the one cylindrical body 31, the top spherical surface 15c of the other cylindrical body 31 is moved to the one cylinder. It strikes against the step 32 provided on the convex spherical surface 15b of the body 31 and is held in that position.
Therefore, the top member 15 does not drop the top when the top members 15 slide by a predetermined angle or more, and the pressing force transmitted from the shape holding portion 19 is transmitted from the convex spherical surface 15b of one cylindrical body 31 to the other. Can be transmitted to the concave spherical surface 15 c of the cylindrical body 31.

  It is assumed that the overtube 10 of this embodiment is used for an endoscope for large intestine. Here, when the large intestine is stretched, the rectum 91 is about 200 mm, the sigmoid colon 92 is about 450 mm, the descending colon 93 is about 250 mm, the transverse colon 95 is about 500 mm, the ascending colon 97 is about 200 mm, and the cecum 98 Is about 50 mm (see FIG. 10). In the state where the rectum 91, the sigmoid colon 92, and the descending colon 93 are folded, the combined length of the large intestine is about 400 mm (see FIG. 11).

  Since the overtube 10 of the present embodiment is for a large intestine endoscope, it is assumed that the large intestine endoscope is inserted into the descending colon 93 without folding the large intestine, and the shape retention and the retention release are repeated. There is a need to assist passage through the sigmoid colon 92. Further, the overtube 10 of this embodiment is inserted into the descending colon 93, and then the shape of the rectum 91, the sigmoid colon 92, and the descending colon 93 up to the descending colon is maintained in a folded state, and the transverse colon 95 → the ascending colon is maintained. 97 → Need to be inserted into the cecum 98.

Therefore, as shown in FIG. 2, the overtube 10 of this embodiment is formed so that the effective length of the flexible tubular portion 11 is about 400 mm.
As a result, the overtube 10 of this embodiment can assist the colonoscopy to pass through the sigmoid colon 92 without folding the large intestine, and the rectum 91, the sigmoid colon 92, and the descending colon 93 are folded. The shape is maintained and can be inserted from the transverse colon 95 to the ascending colon 97 to the cecum 98.

  Further, as described above, in the overtube 10 of the present embodiment, the flexible tubular portion 11 has an effective length of about 400 mm. Therefore, it is difficult to compress the piece members 15 arranged for the length without any difficulty. There is a possibility that sufficient shape holding force cannot be obtained.

Here, in the large intestine, it is known that the rectum 91 closest to the anus is substantially straight in terms of anatomy, and its length is about 200 mm in a fully extended state. Conversely, the large intestine has a straight portion of at least 50 mm even when the rectum 91 is completely folded.
Therefore, the flexible tubular portion 11 is formed with a flexible portion 11b capable of transmitting an operation force amount to the shape holding portion 11a that can be deformed to a length of about 50 to 200 mm, particularly 150 mm from the base end side. ing.

As a result, the flexible tubular portion 11 is configured such that, for example, the flexible portion 11b is surely contained in a rectum 91 (see FIG. 11) that is linearized by a push-pull operation by an operator.
Therefore, the flexible tubular portion 11 can be reduced in weight by reducing the number of pieces of the required piece member 15 and the loss of transmission force by the piece member 15 is reduced. The holding force is small and the operability is improved.

  Further, in order to reduce the weight, the top member 15 is made of a relatively light metal such as aluminum, or a lighter plastic resin such as PEI (polyetherimide) or PEEK (polyetheretherketone). Thereby, since the top member 15 can be reduced in weight, the holding force amount by the shape holding part 19 is small, and the operability is improved.

Next, the operation of the overtube 10 configured as described above will be described.
The overtube 10 is used when inserting the endoscope insertion portion into the body cavity of the subject. Here, in the same way as described with reference to FIGS. 10 and 11, a colonoscopy will be described as an example.

  First, an endoscope insertion portion (not shown) is inserted through the conduit 13a of the overtube 10, and the endoscope insertion portion is protruded. Next, the surgeon inserts the projected distal end portion of the endoscope insertion portion into the large intestine from the anus 90 (see FIG. 10) of the patient lying on the bed or the like.

  Subsequently, the operator inserts the flexible portion 54 while pushing the proximal side of the flexible portion 54 from the sigmoid colon 92 to the descending colon 93 and the spleen curved portion 94 while bending the bending portion 53 of the endoscope insertion portion 51. When the flexible portion 54 of the endoscope insertion portion 51 is inserted from the sigmoid colon 92 to the vicinity of the descending colon 93, the operator linearizes the flexible portion 54 of the endoscope insertion portion 51 to form an S shape. The colon 92 is linearized (the sigmoid colon 92 is shortened to fold).

Along the straightened flexible portion 54, the operator inserts the overtube 10 from the anus 90 into the sigmoid colon 92 so that the straight state of the sigmoid colon 92 is maintained.
Here, as described above, when the mesh tube 16 is in a relaxed state, the flexible tubular portion 11 of the overtube 10 is soft. When the flexible tubular portion 11 is curved and deformed, the coma member 15 is configured such that the convex spherical surface 15b and the concave spherical surface 15c freely slide in accordance with the curved deformation of the flexible tubular portion 11 and the front and rear coma members. 15 sliding contact positions are displaced.

  At this time, as described above, when the concave spherical surface 15c of the other cylindrical body 31 slides by a predetermined angle with respect to the convex spherical surface 15b of the one cylindrical body 31, the top member 15 has a concave spherical surface 15c of the other cylindrical body 31. Will hit the stepped portion 32 provided on the convex spherical surface 15b of one cylindrical body 31, and will be held in that position without dropping frames.

Therefore, the top member 15 can transmit the pressing force transmitted from the shape holding portion 19 from the convex spherical surface 15 b of one cylindrical body 31 to the concave spherical surface 15 c of the other cylindrical body 31.
In this state, the surgeon operates the fixed ring 22 of the shape holding unit 19 to pull the mesh tube 16 to operate the shape holding function. When the operator operates the fixed ring 22, the pulling force from the fixed ring 22 is applied to the most advanced piece member 15 located on the distal end side of the flexible tubular portion 11. Then, the most advanced piece member 15 is pulled toward the base end in the axial direction, and the concave spherical surface 15 c is pressed against the convex spherical surface 15 b of the next cylindrical body 31.

At this time, the top member 15 can transmit the pressing force in the axial direction from the convex spherical surface 15 b of one cylindrical body 31 to the concave spherical surface 15 c of the other cylindrical body 31, and is sequentially transmitted to the top member 15. The frictional resistance between the convex spherical surface 15b and the concave spherical surface 15c between the top members 15 is increased, and the sliding contact position between the top members 15 is maintained.
Accordingly, in the overtube 10, since the top member 15 hits the step and the top member 15 does not drop, and the desired contact state can always be maintained stably, the flexible tubular portion 11 does not bend any more, The shape retention function can be demonstrated.

  In the first embodiment, by pulling the mesh tube 16 of the flexible tubular portion 11, an axial pressing force is applied to the top member 15 to fix the sliding position between the top members 15. However, since the mesh tube 16 is formed in a tubular shape by a mesh member, the inner diameter of the mesh tube 16 in a relaxed state is obtained by using a phenomenon in which the diameter is reduced when pulled, and the diameter is increased when pushed backward. Is larger than the outer diameter of the piece member 15, the piece members 15 are in sliding contact with each other freely.

  When the flexible tubular portion 11 is deformed and the mesh tube 16 is pulled in the relaxed state of the mesh tube 16, the mesh tube 16 has a diameter substantially equal to or less than the outer diameter of the top member 15. By tightening the cylindrical body 31 in the circumferential direction, the positional relationship between the convex spherical surface 15b and the concave spherical surface 15c between the top members 15 can be held and fixed.

  When the mesh tube 16 is provided between the inner side of the piece member 15 and the outer peripheral side of the inner tube 13, and the mesh tube 16 is pulled to reduce the diameter, the piece member 15 is brought into a free state and the mesh tube 16 is pushed in. When the diameter is increased, the shape can be maintained by pressing from the inner peripheral direction of the top member 15.

Therefore, the overtube 10 pulls the mesh tube 16 and applies an axial pulling force to the top member 15 when the flexible tubular portion 11 is deformed into a desired shape and the deformed state is maintained. The positional relationship of mutual sliding contact between the top members 15 by pressing the top members 15 with each other or by reducing the diameter of the mesh tube 16 from the circumferential direction of the top members 15 By holding the shape, the shape of the flexible tubular portion 11 can be maintained.
As a result, the overtube 10 of this embodiment can guide and insert the endoscope insertion portion while maintaining the shape of the subject.

In addition, you may comprise a top member, for example, in four places, without providing a level | step-difference part in the sliding end of the convex spherical surface 15b of the cylindrical body 31 over a perimeter.
As shown in FIG. 6, the top member 15 </ b> B is configured by providing four stepped portions 33 at the sliding end of the convex spherical surface 15 b of the cylindrical body 31, and using the butting surface 33 a of the stepped portion 33 as a butted portion. Thereby, the top member 15B can obtain the same effect as the first embodiment.

  FIGS. 7 to 9 relate to the second embodiment of the present invention, FIG. 7 is a perspective view showing a top member constituting the overtube of the second embodiment, and FIG. 8 is a view in which the top members of FIG. FIG. 9 is a perspective view of a top member showing a modification of FIG. 7.

  In the first embodiment, the step portion 32 is provided at the sliding end of the convex spherical surface 15b of the cylindrical body 31 and the abutting surface 32a of the step portion 32 is used as the abutting portion. A step 32 is provided at the sliding end of the concave spherical surface 15c, and the abutment surface 32a of the step 32 is configured as an abutment. Since the other configuration is the same as that of the first embodiment, the description will be omitted, and the same components will be described with the same reference numerals.

  That is, as shown in FIGS. 7 and 8, the top member 15C constituting the overtube of Example 2 is provided with a step 34 over the entire circumference at the sliding end of the concave spherical surface 15c of the cylindrical body 31, The abutting surface 34a of the stepped portion 34 is used as an abutting portion.

Accordingly, when the concave spherical surface 15c of the other cylindrical body 31 slides by a predetermined angle with respect to the convex spherical surface 15b of the one cylindrical body 31, the top member 15C has a stepped portion provided on the concave spherical surface 15c of the other cylindrical body 31. 34, the convex spherical surface 15b of one cylindrical body 31 hits and is held at that position.
Accordingly, the top member 15C can transmit the pressing force transmitted from the shape holding portion 19 from the concave spherical surface 15c of one cylindrical body 31 to the convex spherical surface 15b of the other cylindrical body 31.

Next, the operation of the overtube configured as described above will be described.
The overtube of Example 2 is used for colonoscopy similarly to Example 1 above, and when the sigmoid colon 92 is linearized, along the flexible portion 54 that is linearized, The anus 90 is inserted into the sigmoid colon 92 to maintain the straight state of the sigmoid colon 92.

  Here, in the same manner as described in the first embodiment, in the overtube, when the mesh tube 16 is in a relaxed state, the flexible tubular portion 11 is soft. When the flexible tubular portion 11 is curved and deformed, the top member 15C has the front and back coma members that the convex spherical surface 15b and the concave spherical surface 15c freely slide according to the curved deformation of the flexible tubular portion 11. The sliding contact position of 15C is displaced.

  At this time, as described above, when the top member 15C slides the concave spherical surface 15c of the other cylindrical body 31 with respect to the convex spherical surface 15b of the one cylindrical body 31 by a predetermined angle, the other cylindrical body 31 The convex spherical surface 15b of one cylindrical body 31 hits the stepped portion 34 provided on the concave spherical surface 15c, and is held at that position without dropping frames.

Accordingly, the top member 15C can transmit the pressing force transmitted from the shape holding portion 19 from the convex spherical surface 15b of one cylindrical body 31 to the concave spherical surface 15c of the other cylindrical body 31.
In this state, the surgeon operates the fixed ring 22 of the shape holding unit 19 to pull the mesh tube 16 to operate the shape holding function.

  When the operator operates the fixed ring 22, the pulling force from the fixed ring 22 is applied to the most advanced piece member 15 </ b> C located on the distal end side of the flexible tubular portion 11. Then, the most advanced piece member 15 </ b> C is pulled toward the base end side in the axial direction, and the concave spherical surface 15 c is pressed against the convex spherical surface 15 b of the next cylindrical body 31.

  At this time, the top member 15C can transmit the pressing force in the axial direction from the convex spherical surface 15b of the one cylindrical body 31 to the concave spherical surface 15c of the other cylindrical body 31, and is sequentially transmitted to the top member 15C. Thus, the frictional resistance between the convex spherical surface 15b and the concave spherical surface 15c between the top members 15C is increased, and the sliding contact position between the top members 15C is maintained.

  Therefore, since the top member 15C hits a step and the top members 15C do not drop, the overtube can always maintain a desired contact state stably. The holding function can be demonstrated.

  In addition, the overtube of the second embodiment may hold the mutual sliding positional relationship between the top members 15C by the reduced diameter and the expanded diameter of the mesh tube 16 as in the first embodiment. The mesh tube 16 is provided between the inner side of the top member 15C and the outer peripheral side of the inner tube 13, and the mutual sliding positional relationship between the top member 15C is held by the reduced diameter and the expanded diameter of the mesh tube 16. Also good.

Therefore, in the overtube of the second embodiment, when the flexible tubular portion 11 is deformed into a desired shape and the deformed state is maintained, the mesh tube 16 is pulled, and the top member 15C is pulled in the axial direction. The top members 15C are pressed against each other, or the diameter of the mesh tube 16 is reduced, and the tops are pressed from the circumferential direction of the top members 15C, and the sliding contacts between the top members 15C are made. By maintaining this positional relationship, the shape of the flexible tubular portion 11 can be maintained.
Thereby, the overtube of Example 2 can acquire the effect similar to the said Example 1. FIG.

Note that the top member may be configured by providing the stepped portion at, for example, four locations without providing the stepped portion at the sliding end of the concave spherical surface 15c of the cylindrical body 31 over the entire circumference.
As shown in FIG. 9, the top member 15 </ b> D is configured by providing four step portions 35 at the sliding end of the concave spherical surface 15 c of the cylindrical body 31, and using the abutting surface 35 a of the step portion 35 as an abutting portion. Thereby, the top member 15D can obtain the same effects as those of the second embodiment.

  The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the invention.

[Appendix]
According to the embodiment of the present invention described in detail above, the following configuration can be obtained.
(Additional item 1)
A flexible tubular portion having a conduit through which the endoscope can be inserted and passively deforming in response to a shape change of the inserted endoscope;
A plurality of coma members arranged in an axially overlapping and sliding manner along the conduit of the flexible tubular portion; and
An abutting portion provided at the sliding end of the top member for holding the top end of the plurality of top members against each other when the plurality of top members are in sliding contact with each other and slide over a predetermined angle; ,
An endoscope overtube characterized by comprising:

(Appendix 2)
The endoscope overtube according to claim 1, wherein the abutting portion is an abutting surface of a stepped portion provided at each sliding end of the plurality of top members.
(Additional Item 3)
Each of the plurality of top members is a cylindrical body having a convex spherical surface at the front end surface and a concave spherical surface at the rear end surface, and the abutting portion is a stepped portion provided on the convex spherical surface of the cylindrical body or the concave spherical surface of the cylindrical body. The overtube for an endoscope according to Additional Item 1, wherein the overtube is an abutting surface.

(Appendix 4)
A flexible tubular portion having a conduit through which the endoscope can be inserted and passively deforming in response to a shape change of the inserted endoscope;
A plurality of coma members arranged in an axially overlapping and sliding manner along the conduit of the flexible tubular portion; and
When the flexible tubular portion deforms in response to the shape change of the endoscope, the overlapping sliding contact state of each of the plurality of top members is maintained, and the shape of the flexible tubular portion A shape holding part for holding
Comprising
The flexible tubular portion has a flexible portion capable of transmitting an operation force amount to a shape-retaining shape-retaining portion, and the flexible portion is approximately about from the proximal end side of the flexible tubular portion. An overtube for an endoscope which is formed to a length of 50 to 200 mm.
(Appendix 5)
The endoscope overfill according to claim 4, wherein the flexible tubular portion is formed such that the flexible portion has a length of about 150 mm from a proximal end side of the flexible tubular portion. tube.

  The endoscope overtube of the present invention is suitable for the medical field because the endoscope insertion portion can be guided and inserted while maintaining the shape of the subject.

1 is an overall configuration diagram showing an endoscope overtube of Example 1. FIG. It is sectional drawing of the overtube for endoscopes of FIG. It is explanatory drawing which shows a mode that the top members generally assumed are in sliding contact with each other. It is a perspective view which shows the top member of this invention. It is explanatory drawing which shows a mode that the piece members of FIG. 4 mutually slide-contact. It is a perspective view of the top member which shows the modification of FIG. It is a perspective view which shows the top member which comprises the overtube of Example 2. FIG. It is explanatory drawing which shows a mode that the top members of FIG. 7 mutually slide-contact. It is a perspective view of the top member which shows the modification of FIG. FIG. 10 is an explanatory diagram showing a state of the endoscope at the time of colonoscopy. It is explanatory drawing which shows the mode of the conventional endoscope overtube which performs the insertion assistance of this endoscope with respect to the endoscope of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 End tube for endoscope 11 Flexible tubular part 11a Shape holding part 11b Flexible part 12 Operation part 13 Inner tube 14 Outer tube 15 Top member 15b Convex spherical surface 15c Concave spherical surface 16 Reticulated tube 17 Grasping part 19 Shape holding part 18 Frame member fixed tube portion 22 Fixed ring 23 Outer tube fixed tube portion 31 Cylindrical body 32 Stepped portion 32a Abutting surface Agent Patent attorney Susumu Ito

Claims (3)

A flexible tubular portion having a duct through which the endoscope can be inserted and passively deforming in response to a shape change of the inserted endoscope;
A plurality of coma members arranged in an axially overlapping and sliding manner along the conduit of the flexible tubular portion; and
An abutting portion provided at the sliding end of the top member for holding the top end of the plurality of top members against each other when the plurality of top members are in sliding contact with each other and slide over a predetermined angle; ,
An endoscope overtube characterized by comprising:   The endoscope overtube according to claim 1, wherein the abutting portion is an abutting surface of a stepped portion provided at each sliding end of the plurality of top members. Each of the plurality of top members is a cylindrical body having a convex spherical surface at the front end surface and a concave spherical surface at the rear end surface, and the abutting portion is a stepped portion provided on the convex spherical surface of the cylindrical body or the concave spherical surface of the cylindrical body. The overtube for an endoscope according to claim 1, wherein the overtube is an abutting surface.

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