JP2015019938A - Stent delivery system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stent delivery system capable of discharging and indwelling a stent inside an organic lumen without lengthening the full length of a grip even when using a stent having a fairly long full length or a plurality of stents.SOLUTION: A movement mechanism 52 of a stent delivery system 10 has: a rack member 54 connected to an outer tube 16, being able to move in the axial direction, and extending in the axial direction; and a plurality of pinions 56 disposed in the extension direction of the rack member 54 at intervals from each other, and moving the rack member 54 according to rotation.

Description

  The present invention relates to a stent delivery system for delivering and placing a stent in a biological lumen such as a blood vessel.

  Conventionally, a stent is used to improve a stenosis or occlusion occurring in a body lumen such as a blood vessel, a bile duct, a trachea, an esophagus, or a urethra. The stent is formed into a cylindrical shape as a whole by a metal wire or the like, and is configured to have a large number of side wall openings, and is expandable in a living body lumen.

  One type of stent is a balloon expandable stent that is placed on the balloon of a balloon catheter and is placed in the living body lumen by being expanded from the inside by the balloon. As another type of stent, there is a self-expanding stent that has a self-expanding function by an elastic force, is released from a sheath or the like in the living body lumen, and is self-expanded to be placed in the living body lumen. A stent delivery system is used to deliver and place such a balloon-expandable stent or self-expandable stent at a desired position in a living body lumen.

  In general, a conventional stent delivery system for a self-expanding stent has a long inner tube, a stent placed on the outer side near the distal end of the inner tube, and an axially displaceable outer side of the inner tube. An outer tube that houses the contracted stent, and a grip connected to the proximal end of the outer tube. In the procedure using the stent delivery system, the stent is delivered to the living body lumen while being compressed and stored in the gap between the inner tube and the outer tube, and the outer tube is moved in the proximal direction with respect to the inner tube. Thus, the stent is released and placed in the living body lumen.

  In the stent delivery system, the grip is further provided with a moving mechanism for moving the outer tube relative to the inner tube in the axial direction. The moving mechanism includes a rotatable operation wheel and a rack member provided with a rack that meshes with a pinion provided on the operation wheel. The proximal end portion of the outer tube is connected to the rack member. When the operation wheel of such a moving mechanism is rotated in a predetermined direction, the rack member moves backward, and accordingly, the outer tube moves backward with respect to the inner tube, and the stent moves from the outer tube into the living body lumen. Released. In addition, as a document disclosing the conventional stent delivery system, there exists patent document 1, for example.

Special table 2007-504897 gazette

  By the way, some stents have a considerably long overall length (for example, 20 cm or more) depending on a treatment site. In some cases, a plurality of stents are arranged in the axial direction of the inner tube, and the plurality of stents are released and placed in the body lumen. In order to release a stent having a considerably long overall length or a plurality of stents into the living body lumen, it is necessary to increase the movement distance of the rack member in the proximal direction from the initial position. In the conventional stent delivery system, the rack member is moved by one pinion. Therefore, in order to move the rack member backward by the necessary moving distance, the total length of the rack member corresponding to the required moving distance is required. is there. Since the rack member is arranged so as to extend from the pinion side toward the distal end at the initial position, the grip must be extended toward the distal end according to the length of the rack member. As a result, there is a problem that the overall length of the grip becomes long and the handling ease during the procedure is reduced.

  In view of such problems, the present invention can release and place a stent in a living body lumen without increasing the overall length of the grip even when a stent having a considerably long overall length or a plurality of stents is used. An object of the present invention is to provide a stent delivery system that can be used.

  In order to achieve the above object, the present invention includes a long inner member, a sheath disposed on the outer side of the inner member so as to be axially movable with respect to the inner member, the inner member and the sheath. And a grip including a moving mechanism for moving the sheath in the axial direction with respect to the inner member, and the stent is accommodated in the sheath in an initial state. A stent delivery system that releases the stent into a living body lumen as the sheath moves in the proximal direction with respect to the inner member, wherein the moving mechanism is connected to the sheath and is connected to the sheath. A displacement member that is movable in the axial direction and extends in the axial direction, and is disposed at a distance from each other in the extending direction of the displacement member. And having a plurality of drive rotor is moved in the extending direction.

  According to the above-described stent delivery system, the displacement members are sequentially sent in the proximal direction by the plurality of drive rotators provided at intervals from each other along the extending direction of the displacement member. With this configuration, the total length of the displacement member can be shortened compared to a configuration in which the displacement member is moved by one drive rotator. Therefore, even in the case of a configuration in which a long stent or a plurality of stents arranged in the axial direction are released, the movement distance necessary for the displacement member can be ensured without increasing the total length of the displacement member. For this reason, since the length of the displacement member can be shortened, the length of the grip can be saved, and the handleability of the grip during the procedure can be improved.

  In the above stent delivery system, the plurality of stents are arranged side by side along the axial direction of the inner member, and the number of the drive rotating bodies is the same as the number of the stents, and the drive is sequentially performed from the distal end side. Each time the rotating body is rotated, the stent may be released from the sheath in order from the distal end side.

  According to the above configuration, when a plurality of stents are provided, the stent is released from the sheath in order from the distal end side by rotating the drive rotating body in order from the distal end side. That is, since a plurality of drive rotating bodies are provided corresponding to the arrangement of a plurality of stents, only the stent to be released can be reliably released by a simple operation at each stage of releasing the plurality of stents.

  In the above stent delivery system, the moving distance of the displacement member per unit rotation angle of the drive rotator may be different between at least one of the drive rotators and the other drive rotators.

  According to said structure, the moving speed at the time of moving a displacement member is not constant, and changes with drive rotary bodies. For this reason, it is possible to control the release speed at each stage of releasing the stent from the sheath by the arrangement of the driving rotating body, and it is possible to perform the procedure appropriately and efficiently.

  In the above stent delivery system, the plurality of drive rotators include a plurality of first drive rotators and a plurality of second drive rotators, and at least one of the first drive rotators is always within a movable range of the displacement member. A drive rotator and at least one second drive rotator can drive the displacement member, and the displacement distance of the displacement member per unit rotation angle of the plurality of first drive rotators, The moving distance of the displacement member per unit rotation angle of the second drive rotor may be different.

  According to said structure, the speed which moves a displacement member differs with a 1st drive rotary body and a 2nd drive rotary body. For this reason, the discharge speed from the sheath of the stent can be easily controlled by rotating the first drive rotor or the second drive rotor according to the speed at which the stent is desired to be released.

  In the above stent delivery system, the displacement member has first and second driven parts on opposite sides, and the plurality of first drive rotators are in contact with the first driven part and are displaced. The member may be driven, and the plurality of second drive rotators may be in contact with the second driven portion to drive the displacement member.

  According to said structure, since a 1st drive rotary body and a 2nd drive rotary body are arrange | positioned on the opposite side mutually on the basis of the movement path | route of a displacement member, two or more 1st drive rotary bodies and 2nd drive provided The rotating body can be efficiently arranged in the grip.

  In the above-described stent delivery system, each of the plurality of first rotation operation units rotatably supported by the grip is provided with the first drive rotating body, and a plurality of second rotation units rotatably supported by the grip. Each of the rotation operation units is provided with the second drive rotator, and the plurality of first rotation operation units and the plurality of second rotation operation units are exposed on opposite outer sides of the grip. May be.

  According to said structure, since a 1st rotation operation part and a 2nd rotation operation part are exposed from a grip on the mutually different side, it is easy for a user to distinguish a 1st rotation operation part and a 2nd rotation operation part. Yes, easy to use properly.

  In the above stent delivery system, the movement distance of the displacement member per unit angle of the drive rotator provided on the most proximal side is the displacement per unit angle of the drive rotator provided on the most distal side. It may be larger than the moving distance of the member.

  According to the above configuration, positioning can be facilitated by slowly releasing the stent at the initial stage of release of the stent, and the procedure can be quickly completed by releasing quickly at the end of the release of the stent.

  In the above stent delivery system, the driving rotating body provided at the most distal end side is provided at a first rotation operation unit rotatably supported by the grip, and the driving rotating body provided at the most proximal end side. Is provided in a second rotation operation unit rotatably supported by the grip, and the first rotation operation unit and the second rotation operation unit are exposed on outer surfaces of the grip opposite to each other. Also good.

  According to said structure, since a 1st operation wheel and a 2nd operation wheel are exposed from a grip on the mutually different side, it is easy for a user to distinguish between a 1st operation wheel and a 2nd operation wheel. Easy to do.

  In the above stent delivery system, the position of the displacement member may be visible from the outside of the grip.

  According to the above configuration, since the position of the displacement member can be seen during the procedure, it is possible to easily know the timing for changing the drive rotating body to be rotated, and the stent release procedure can be performed with an efficient operation. .

  According to the stent delivery system of the present invention, even when a stent having a considerably long overall length or a plurality of stents are used, the stent can be released and placed in a living body lumen without increasing the overall length of the grip.

1 is a partially omitted side view of a stent delivery system according to a first embodiment of the present invention. FIG. 3 is a partially omitted longitudinal sectional view of an inner tube and an outer tube in the stent delivery system shown in FIG. 1. It is a perspective view of the moving mechanism in the stent delivery system shown in FIG. 4A is a first diagram for explaining the operation of the stent delivery system shown in FIG. 1, and FIG. 4B is a second diagram for explaining the operation of the stent delivery system shown in FIG. FIG. 4 is a third diagram for explaining the operation of the stent delivery system shown in FIG. 1. FIG. 5A is a first diagram illustrating the operation of the modified example of the stent delivery system, FIG. 5B is a second diagram illustrating the operation of the modified example of the stent delivery system, and FIG. 5C is a diagram illustrating the stent delivery. It is a 3rd figure explaining operation | movement of the modification of a system. It is a partially omitted side view of a stent delivery system according to a second embodiment of the present invention. It is a partially omitted side view of a stent delivery system according to a third embodiment of the present invention.

  Hereinafter, preferred embodiments of the stent delivery system according to the present invention will be described with reference to the accompanying drawings.

[First Embodiment]
FIG. 1 is a partially omitted side view of a stent delivery system 10 according to a first embodiment of the present invention. In FIG. 1, for convenience of illustration, illustration of an intermediate portion in the axial direction of the stent delivery system 10 is omitted, and the distal end side (stent 12 side) is made larger than the proximal end side (grip 18 side) of the stent delivery system 10. I'm drawing. This also applies to FIGS. 6 and 7 showing the second and third embodiments.

  The stent delivery system 10 is a medical instrument for delivering and placing the stent 12 at a desired position in a biological lumen such as a blood vessel, a bile duct, a trachea, an esophagus, or a urethra. The stent delivery system 10 is disposed between a long inner tube 14 (inner member), an outer tube 16 (sheath) disposed outside the inner tube 14, and the inner tube 14 and the outer tube 16. A self-expandable stent 12 and a grip 18 provided on the proximal side of the outer tube 16 are provided.

  With respect to the stent delivery system 10 in FIG. 1, the side or direction in which the grip 18 is provided is referred to as “proximal side” or “proximal direction”, and the opposite side or opposite direction is referred to as “distal side” or “distal direction”. The same applies to the other figures.

  As shown in FIG. 2, the inner tube 14 is connected to an inner distal tube 24 in which a guide wire lumen 22 for inserting the guide wire 20 is formed, and a proximal end side of the inner distal tube 24 via a connecting member 26. And an inner proximal tube 28 formed. The distal end of the inner tube 14, that is, the distal end of the inner distal tube 24 protrudes further toward the distal end side than the distal end of the outer tube 16.

  A tip opening 24 a that opens in the tip direction is formed at the tip of the inner tip tube 24. The proximal end of the inner distal tube 24 is curved toward the radially outer side of the inner distal tube 24 to form a proximal opening 24b that opens radially outward. In the initial state of the stent delivery system 10 (the state shown in FIG. 2), the proximal end opening 24b communicates with a guide wire outlet hole 44 described later. The guide wire 20 is used, for example, for guiding the stent delivery system 10 to a lesion in a living body lumen.

  A stopper portion 32 that bulges outward in the radial direction and restricts the movement of the outer tube 16 in the distal direction is formed at the distal end of the inner distal tube 24. The stopper portion 32 restricts the movement of the outer tube 16 in the distal direction, thereby preventing the outer tube 16 from protruding in the distal direction with respect to the distal end of the inner tube 14.

  The connecting member 26 is connected to the proximal end of the inner distal end tube 24 and the distal end of the inner proximal end tube 28. The inner proximal tube 28 has a lumen 34 that extends from the distal end to the proximal end. As shown in FIG. 1, the inner proximal tube 28 projects in the proximal direction from the proximal end of the outer tube 16 in the grip 18, and extends linearly in the grip 18.

  The proximal end portion of the inner proximal tube 28 is connected to a connector 36 provided at the proximal end portion of the grip 18. The connector 36 can be connected to a liquid injector for supplying a liquid such as physiological saline to the stent delivery system 10. The proximal end portion of the inner proximal tube 28 and the connector 36 are fixed, whereby the inner tube 14 is fixed so as not to move in the axial direction with respect to the grip 18.

  Such an inner tube 14 can be made of a resin material, a metal material, or the like. The inner distal tube 24 may be made of a material that is more flexible than the inner proximal tube 28.

  The outer tube 16 is provided so as to be movable in the axial direction with respect to the inner tube 14 and the grip 18. In the illustrated example, the outer tube 16 includes an outer distal tube 38 and an outer proximal tube 40 connected to the proximal end of the outer distal tube 38. Inside the outer tip tube 38, the inner tip tube 24 of the inner tube 14 is disposed.

  Inside the outer proximal tube 40, the inner proximal tube 28 of the inner tube 14 is disposed. The proximal end portion of the outer tube 16, that is, the proximal end portion of the outer proximal tube 40 is inserted into the grip 18.

  The distal end of the outer distal tube 38 functions as a release port of the stent 12 when the stent 12 is placed in a lesioned part in the living body lumen, and is stored when the released stent 12 is collected (re-stored). It also functions as a mouth.

  In the vicinity of the proximal end of the outer distal tube 38, a guide wire outlet hole 44 that communicates the inside and outside of the outer distal tube 38 is formed. As shown in FIG. 2, in the initial state of the stent delivery system 10, the proximal end opening 24 b of the inner distal tube 24 and the guide wire outlet hole 44 communicate with each other. Therefore, the guide wire 20 is inserted into the guide wire lumen 22 through the distal end opening 24 a of the inner distal end tube 24, and the guide wire 20 is moved to the outside of the outer tube 16 through the proximal end opening 24 b and the guide wire outlet hole 44. Can be derived.

  As shown in FIG. 2, a contrast marker 42 made of an X-ray (radiation) opaque material may be provided on the outer peripheral surface of the distal end portion of the outer distal tube 38.

  The stent 12 is formed in a substantially cylindrical shape and self-expandable. Specifically, the stent 12 is disposed in a contracted state between the inner tube 14 and the outer tube 16 in the initial state of the stent delivery system 10. That is, the stent 12 is housed in the outer tube 16 in a state in which expansion is restricted by the outer tube 16 and compressed in the radially inward direction. In addition, the stent 12 is released from the outer tube 16 as the outer tube 16 moves in the proximal direction with respect to the inner tube 14, and thereby expands radially outward by its own elastic restoring force. The length Ls of the stent 12 varies depending on the site to be treated, and is, for example, about 10 to 300 mm, preferably about 40 to 250 mm.

  The stent 12 may be configured, for example, as a mesh-like configuration having a large number of side holes, a configuration in which a large number of circular annular bodies are connected in the axial direction, or an annular body extending in a zigzag manner in the circumferential direction. Examples include a configuration in which a large number of units are connected in the direction. As a material constituting the stent 12, for example, a superelastic alloy such as a Ni-Ti alloy is suitable. For example, a contrast marker made of a radiopaque material may be provided at the distal end and the proximal end of the stent 12.

  As shown in FIG. 2, a stent holding mechanism 46 that restricts the movement of the stent 12 in the axial direction is provided on the outer peripheral portion of the inner tube 14 (specifically, the inner distal end tube 24). The stent holding mechanism 46 includes a receding prevention stopper 47 that prevents the movement of the stent 12 in the proximal direction, and an advance prevention stopper 48 that prevents the movement of the stent 12 in the distal direction.

  Specifically, the receding prevention stopper 47 is engaged with the reduced proximal end of the stent 12 when the outer tube 16 is moved proximally relative to the inner tube 14 to release the stent 12. Thus, the backward movement of the stent 12 is prevented. The advance prevention stopper 48 is used to reduce the proximal end of the stent 12 when the outer tube 16 is moved in the distal direction with respect to the inner tube 14 in order to re-store the stent 12 released halfway in the outer tube 16. Is engaged to prevent forward movement of the stent 12.

  In FIG. 1, a grip 18 constituting a proximal end portion of the stent delivery system 10 is a portion that functions as a handle for a user to hold and operate with a hand. The grip 18 has a hollow housing 50 and is configured to be slightly longer in the axial direction (front-rear direction) of the stent delivery system 10. A movement mechanism 52 for moving the outer tube 16 in the axial direction with respect to the inner tube 14 is provided in the housing 50.

  As shown in FIGS. 1 and 3, the moving mechanism 52 is connected to the outer tube 16 and is movable in the axial direction of the stent delivery system 10 and extends in the axial direction, and a rack member 54 (displacement member), A plurality (three in the illustrated example) of pinions 56 (drive rotating bodies) that are arranged at intervals in the extending direction of the rack member 54 and move the rack member 54 in the extending direction with rotation, and each pinion And a plurality (three in the illustrated example) of operation wheels 58 provided with 56. Two or four or more pinions 56 may be provided. In this case, two or four or more operation wheels 58 may be provided.

  The rack member 54 is supported by a guide portion (not shown) provided in the housing 50 so as to be slidable in the axial direction of the stent delivery system 10 (the longitudinal direction of the grip 18). Since the rack member 54 is fixed to the base end portion of the outer tube 16, the outer tube 16 also moves in conjunction with the rack member 54. A rack 55 made up of a plurality of teeth along the axial direction of the rack member 54 is provided on the rack member 54 (the lower surface of the rack member 54 in the illustrated example).

  As a position confirmation means of the rack member 54, a part or all of the housing 50 is made of a material having transparency, or an opening for exposing the rack member 54 is provided in a part of the housing 50, and the inside of the housing 50 The position of the rack member 54 may be visible from the outside of the housing 50. Alternatively, as another configuration of the position confirmation means, a projection is provided on the rack member 54, the projection is projected from the housing 50 through a slit provided in the housing 50, and the position of the rack member 54 is known by the position of the projection. Also good.

  Each pinion 56 (56a to 56c) can mesh with the rack 55 of the rack member 54. The rotational axes of the three pinions 56 are parallel to each other. The rotational axes of the three pinions 56 exist on a single straight line parallel to the movable direction (extending direction) of the rack member 54.

  In FIG. 1, the distance L2 between the centers of two adjacent pinions 56 in the three pinions 56a to 56c is all equal. The length L1 of the rack member 54 (the length of the rack 55) is larger than the center distance L2 of the pinion 56. For this reason, the rack 55 can be engaged with at least two adjacent pinions 56. In the three pinions 56a to 56c, the number of teeth and the modules are all the same. The module (m) is a value obtained by dividing the pitch circle diameter (d) by the number of teeth (z).

  The plurality of pinions 56 are respectively provided at the central portions of the plurality of operation wheels 58 (58a to 58c). The operation wheels 58 a to 58 c are arranged at intervals in the front-rear direction of the grip 18. As shown in FIG. 3, an anti-slip shape in which grooves 60 and protrusions 61 are alternately arranged in the circumferential direction is provided on the outer peripheral portion of each operation wheel 58. Each operation wheel 58 has a shaft portion 62 protruding in the axial direction. Each shaft portion 62 is supported by a bearing portion provided inside the housing 50. Thereby, each operation wheel 58 is rotatably supported by the housing 50.

  In FIG. 1, the housing 50 is provided with a plurality of openings 64 for partially exposing each operation wheel 58. The user can rotate the operation wheel 58 by touching a portion of the operation wheel 58 exposed from the opening 64. In the illustrated example, all the openings 64 are provided on the same side (upper side) of the housing 50.

  The grip 18 is provided with a lock mechanism 66 capable of restricting the movement operation of the rack member 54 by restricting the rotation operation of the operation wheel 58a disposed on the most distal side among the plurality of operation wheels 58. The lock mechanism 66 includes a slide member 68 that is slidably provided on the side surface of the housing 50. The slide member 68 is movable between a lock position where the rotation operation of the operation wheel 58 is prevented and a release position where the rotation operation of the operation wheel 58 is allowed. The slide member 68 is provided with a lock pin (not shown) that protrudes inward of the housing 50.

  On the other hand, the operation wheel 58a is provided with an engagement portion (for example, a groove portion) (not shown) that can be engaged with the lock pin. When the slide member 68 is in the locked position, the lock pin engages with the engaging portion, thereby preventing the operation wheel 58a from rotating. On the other hand, when the slide member 68 is in the release position, the lock pin is disengaged from the engaging portion, thereby allowing the operation wheel 58a to rotate.

  The stent delivery system 10 according to the present embodiment is basically configured as described above, and the operation and effect thereof will be described below.

  In a procedure for treating a lesion occurring in a living body lumen (for example, in a blood vessel) using the stent delivery system 10, the guide wire 20 is inserted into the living body tube prior to insertion of the stent delivery system 10 into the living body lumen. Insert into the cavity. And let the front-end | tip of the guide wire 20 be the state reached to the lesioned part (stenosis part) in a biological lumen.

  In such a state, flushing is performed to fill the inside tube 14 and the outside tube 16 in the stent delivery system 10 outside the living body with a predetermined liquid (for example, physiological saline or the like). In the flush, first, the operator connects a liquid injection tool (not shown) to the connector 36 provided at the proximal end of the grip 18, and supplies a liquid such as physiological saline from the liquid injection tool to the connector 36. inject. As a result, the liquid flows toward the distal ends of the inner tube 14 and the outer tube 16 and flows out from the distal ends of the inner tube 14 and the outer tube 16. Thereby, the flushing of the inside of the inner tube 14 and the outer tube 16 outside the living body is completed.

  Next, as shown in FIG. 2, the proximal end of the guide wire 20 exposed to the outside of the living body is inserted from the distal end of the inner tube 14 to the guide wire lumen 22, and the outer tube 16 is passed through the guide wire outlet hole 44. To the outside. Then, the inner tube 14 and the outer tube 16 are advanced into the living body lumen along the guide wire 20.

  Then, after confirming with the contrast marker 42 that the distal end of the outer tube 16 has reached the lesioned part, the slide member 68 provided on the grip 18 is moved to the distal end side, whereby the rotation restriction state of the operation wheel 58a is changed. To release. At this time, as shown in FIG. 4A, the rack member 54 is located at the most distal end side of the movable range. In FIG. 4A, the position of the rack member 54 when the stent 12 is completely released from the distal end of the outer tube 16 is indicated by a dotted line. Reference symbol L3 is a necessary moving distance of the rack member 54 for completely releasing the stent 12 from the distal end of the outer tube 16.

  When the rotation restriction state of the operation wheel 58a is released, a part of the operation wheel 58a exposed from the housing 50 through the opening 64 is touched to rotate the operation wheel 58a in a predetermined direction (arrow A direction). As a result, the rack member 54 moves to the proximal side in the housing 50 with the rotation of the pinion 56a provided on the operation wheel 58a, whereby the outer tube 16 connected to the rack member 54 is also gripped. 18 moves toward the proximal direction.

  As a result, as the outer tube 16 moves in the proximal direction with respect to the inner tube 14, the stent 12 (see FIG. 1) accommodated in the outer tube 16 begins to be gradually exposed from the distal end side. At the same time, it begins to expand radially outward. That is, as the outer tube 16 moves in the proximal direction, the stent 12 is released. Note that when the position of the stent 12 in the living body lumen is to be adjusted after the stent 12 has been released halfway, the operation wheel 58a may be rotated in the reverse direction (arrow B direction). Thereby, the outer tube 16 moves in the distal direction, and the stent 12 can be re-stored in the outer tube 16.

  When the rack member 54 moves in the proximal direction along with the rotation operation of the operation wheel 58a, the rack 55 of the rack member 54 eventually becomes one pinion 56b provided on the proximal end side as shown in FIG. 4B. Mesh with. At this time, the stent 12 is in a state of being released halfway (about one third of the total length). When the rack 55 of the rack member 54 meshes with the pinion 56b, the outer tube 16 is moved in the proximal direction by rotating the operation wheel 58b provided with the pinion 56b in a predetermined direction (direction A), The stent 12 is further released.

  When the pinion 56b provided on one base end side operation wheel 58b is engaged with the rack member 54 during the rotation operation of the operation wheel 58a, the operation wheel 58b is rotated in conjunction with the rack member 54. Thereby, the user can recognize that the rack 55 of the rack member 54 is engaged with the pinion 56b. Further, when the rack member 54 moves in the proximal direction along with the rotation operation of the operation wheel 58a, the pinion 56a and the rack 55 are eventually disengaged, and the operation wheel 58a is idled. For this reason, the user can recognize that the rack member 54 is engaged with the next pinion 56b, and can recognize that the next operation wheel 58b should be operated. In addition, when the grip 18 is provided with a position confirmation unit that can visually recognize the position of the rack member 54, the user recognizes that the rack member 54 is engaged with the next pinion 56b by looking at the position of the rack member 54. Then, it can be recognized that the next operation wheel 58b should be operated.

  When the rack member 54 moves in the proximal direction in accordance with the rotation operation of the operation wheel 58b, the rack 55 of the rack member 54 eventually has a pinion provided on one proximal end side as shown in FIG. 4C. Meshes with 56c. At this time, the stent 12 is still released halfway (about two-thirds of the total length). When the rack 55 of the rack member 54 meshes with the pinion 56c, the outer tube 16 is moved in the proximal direction by rotating the operation wheel 58c provided with the pinion 56c in a predetermined direction (direction A), The stent 12 is further released.

  And the stent 12 will be in the state completely exposed with respect to the outer side tube 16 (state which the full length of the stent 12 was discharge | released). As a result, the stent 12 is indwelled in the lesioned part in a state of being expanded in a cylindrical shape.

  Thereafter, by pulling the inner tube 14 and the outer tube 16 constituting the stent delivery system 10 toward the proximal end side, only the stent 12 is left in the living body lumen, and the inner tube 14 and the outer tube 16 are moved out of the living body. Remove.

  As described above, according to the stent delivery system 10 according to the first embodiment of the present invention, the plurality of pinions 56 (56a to 56c) provided at intervals from each other along the extending direction of the rack member 54. Thus, the rack members 54 are sequentially sent in the proximal direction. For this reason, the length L1 of the rack member 54 is considerably shorter than the required moving distance L3 of the rack member 54 (see FIG. 4A). On the other hand, in the case of the conventional configuration in which the rack member is moved by one pinion, the length of the rack member needs to be set to at least the necessary movement distance, and therefore the length of the rack member is considerably long. Therefore, the grip in which the rack member is accommodated must be long.

  As described above, according to the stent delivery system 10, even when the long stent 12 is released, the required moving distance L3 of the rack member 54 can be ensured without increasing the total length of the rack member 54. For this reason, since the length of the rack member 54 can be shortened, the length of the grip 18 can be saved, and the handleability of the grip 18 during the procedure can be improved.

  The rack member 54 is provided in the grip 18. However, as described above, the stent delivery system 10 may be configured such that the position of the rack member 54 is visible from the outside of the grip 18. Good. When configured in this manner, the timing of changing the pinion 56 to be rotated, that is, the operation wheel 58 can be easily known, and the stent 12 can be released by an efficient operation.

  In the above-described embodiment, the rack member 54 is illustrated as the displacement member that moves in the axial direction of the grip 18, and the plurality of pinions 56 are illustrated as the plurality of drive rotators, but the displacement member and the drive rotator are illustrated. Is not limited to a configuration in which power is transmitted by meshing between the rack 55 and the pinion 56. For example, it may be configured to transmit power by frictional resistance caused by contact between the outer surface of the displacement member and the outer peripheral surface of the drive rotating body. This point is the modification described later in the second and third embodiments. Is the same.

  5A to 5C are schematic views showing a stent delivery system 10a according to a modification. 5A to 5C show the grip 18 in a simplified manner. However, like the grip 18 shown in FIG. 1, the grip 18 has a shape suitable for gripping, and a plurality of operation wheels 58 (58d, 58e). ) Is partially exposed from the grip 18.

  In the stent delivery system 10a according to this modification, a plurality (two in the illustrated example) of the stents 12 (12a, 12b) are arranged along the axial direction of the inner tube 14 and the outer tube 16.

  The stent delivery system 10a also includes a moving mechanism 52a for moving the outer tube 16 in the proximal direction with respect to the inner tube 14. In the moving mechanism 52a, the same number of operation wheels 58 as the stent 12 are provided, that is, two in the present modification. Each operation wheel 58 is provided with a pinion 56 (56d, 56e) that can mesh with the rack member 54. In the stent delivery system 10a, every time the pinion 56 is rotated sequentially from the distal end side, the stent 12 is released from the outer tube 16 sequentially from the distal end side.

  Specifically, as shown in FIG. 5A, when the rack member 54 is in the initial position (the most advanced position of the movable range), all the stents 12 are housed in the outer tube 16 in a contracted state. When the first operation wheel 58d is rotated to rotate the pinion 56d and the outer tube 16 is moved together with the rack member 54 in the proximal direction with respect to the inner tube 14, the first stent 12a is moved to the outer tube 16. Will be released from. Then, as shown in FIG. 5B, when the rack member 54 is retracted to a predetermined position, the first stent 12a is completely released from the outer tube 16. At this time, since the rack 55 of the rack member 54 does not mesh with the pinion 56d provided on the first operation wheel 58d, even if the operation wheel 58d is further rotated, the operation wheel 58d rotates idly.

  At the stage where the first stent 12a is released, the rack 55 of the rack member 54 meshes with a pinion 56e provided on the second operation wheel 58e. Therefore, by rotating the second operation wheel 58e, the outer tube 16 is moved in the proximal direction with respect to the inner tube 14 together with the rack member 54 as the pinion 56e rotates. As a result, the second stent 12b is released from the outer tube 16 as shown in FIG. 5C.

  The two stents 12a and 12b may be continuously released without changing the position of the stent delivery system 10a (the tip of the inner tube 14). Alternatively, after the first stent 12a is released, the position of the stent delivery system 10a (the tip of the inner tube 14) is moved, and the second stent 12b is released at another location in the living body lumen. Good.

  In the stent delivery system 10a, three or more stents 12 may be arranged side by side along the axial direction. In this case, three or more pinions 56 and operation wheels 58 are provided in the same number as the number of stents 12, and the stent 12 is sequentially released from the outer tube 16 for each rotation operation of the operation wheel 58.

  According to the stent delivery system 10a according to the modified example, the rack members 54 are sequentially sent in the proximal direction by a plurality of pinions 56 that are spaced from each other along the extending direction of the rack member 54. Yes. With this configuration, the overall length of the rack member 54 can be shortened compared to the conventional configuration in which the rack member is moved by one pinion. Therefore, even in the case of a configuration in which the plurality of stents 12 arranged in the axial direction are released, the necessary moving distance L3 of the rack member 54 can be ensured without increasing the total length of the rack member 54. For this reason, since the length of the rack member 54 can be shortened, the length of the grip 18 can be saved, and the handleability of the grip 18 during the procedure can be improved.

[Second Embodiment]
FIG. 6 is a partially omitted side view of the stent delivery system 70 according to the second embodiment of the present invention. In FIG. 6, the proximal end portion of the inner tube 14 and the grip 72 (housing 50) are indicated by phantom lines. In the stent delivery system 70 according to the second embodiment, elements having the same or similar functions and effects as those of the stent delivery system 10 according to the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. To do.

  The stent delivery system 70 includes a grip 72 having a moving mechanism 52 b for moving the outer tube 16 in the proximal direction relative to the inner tube 14. The moving mechanism 52b includes a rack member 54, a plurality of pinions 84, and a plurality of operation wheels 78 and 80 (rotation operation units). The rack member 54 is provided with a first rack 74 (first driven portion) and a second rack 76 (second driven portion) on opposite sides (upper and lower sides in the illustrated example).

  The plurality of operation wheels 78 and 80 are arranged at intervals in the extending direction (axial direction) of the rack member 54 and are rotatable (two in the illustrated example) first operation wheels 78 (first rotation operation). Part) and a plurality of (three in the illustrated example) second operation wheels 80 (second rotation operation parts) that are arranged at intervals in the extending direction (axial direction) of the rack member 54 and are rotatable. .

  The plurality of first operation wheels 78 (78a, 78b) and the plurality of second operation wheels 80 (80a to 80c) are exposed on opposite outer surfaces (upper and lower surfaces in FIG. 6) of the grip 72. . Specifically, a plurality of openings 64 are provided on the upper surface of the grip 72 corresponding to the plurality of first operation wheels 78, and each first operation wheel 78 is partially exposed through the openings 64. Further, a plurality of openings 64 are provided on the lower surface of the grip 72 corresponding to the plurality of second operation wheels 80, and each second operation wheel 80 is partially exposed through the openings 64.

  The first operation wheel 78 is provided with a first pinion 82 (drive rotator) that can mesh with the first rack 74. The length L1 of the rack member 54 (the length of the first rack 74 and the second rack 76) L1 is greater than the center distance L4 between the first pinions 82. The second operation wheel 80 is provided with a second pinion 84 (drive rotary body) that can mesh with the second rack 76. The length L1 of the rack member 54 is greater than the center-to-center distance L5 between the second pinions 84. Within the movable range of the rack member 54, the rack member 54 meshes with at least one first pinion 82 and meshes with at least one second pinion 84.

  In the present embodiment, the product of the number of teeth of the second pinion 84 and the module is larger than the product of the number of teeth of the first pinion 82 and the module. For this reason, the movement distance of the rack member 54 per unit rotation angle of the second pinion 84 is larger than the movement distance of the rack member 54 per unit rotation angle of the first pinion 82. That is, when the rotation angles are the same, the movement distance of the rack member 54 by driving the second pinion 84 is larger than the movement distance of the rack member 54 by driving the first pinion 82.

  Therefore, when the rotational operation speed for the first operation wheel 78 and the rotational operation speed for the second operation wheel 80 are the same, the outer tube that moves together with the rack member 54 when the first operation wheel 78 is rotationally operated. The moving speed of the outer tube 16 that moves together with the rack member 54 is relatively fast when the second operation wheel 80 is rotated.

  In the plurality of first pinions 82 (82a, 82b), the number of teeth and the module are the same, and in the plurality of second pinions 84 (84a to 84c), the number of teeth and the module are the same. The modules of the first pinion 82 and the second pinion 84 may be the same, but in this case, the number of teeth of the second pinion 84 is larger than the number of teeth of the first pinion 82 as shown in FIG. Alternatively, the number of teeth of the first pinion 82 and the number of teeth of the second pinion 84 may be the same, and the module of the second pinion 84 may be larger than the module of the first pinion 82. Alternatively, the number of teeth and the module of the second pinion 84 may be larger than the number of teeth and the module of the first pinion 82, respectively.

  According to the stent delivery system 70 configured in this manner, the plurality of pinions 82 and 84 are rotated by rotating the first operation wheel 78 or the second operation wheel 80 in order from the distal end side, so that the rack member 54 is moved. Sequentially, the outer tube 16 can be moved in the proximal direction relative to the inner tube 14 in the proximal direction. As the outer tube 16 moves in the proximal direction, the stent 12 is gradually released from the distal end side thereof, and when the rack member 54 moves to the position depicted by the dotted line in FIG. 16 is completely discharged from the tip.

  In this case, the speed at which the rack member 54 is moved is different between the first pinion 82 and the second pinion 84. Therefore, by rotating the first operation wheel 78 or the second operation wheel 80 and rotating the first pinion 82 or the second pinion 84 according to the speed at which the stent 12 is desired to be released, The release rate of the stent 12 can be easily controlled.

  For example, when it is desired to release the stent 12 slowly, the outer tube 16 is driven at a low speed in the proximal direction by rotating the first operation wheel 78 and driving the rack member 54 with the first pinion 82 having a small number of teeth. Move to. On the other hand, when it is desired to release the stent 12 quickly, the outer tube 16 is driven at a high speed in the proximal direction by rotating the second operation wheel 80 and driving the rack member 54 with the second pinion 84 having a large number of teeth. Move to.

  Further, for example, in the case of a long stent 12, at the initial stage of the release of the stent 12, the outer tube 16 is proximally driven by rotating the first operation wheel 78a on the distal end side and driving the rack member 54 by the first pinion 82a. Move in the direction. Then, the stent 12 is released slowly and is easy to position. On the other hand, at the end of the release of the stent 12, the outer tube 16 is moved in the proximal direction by rotating the second operation wheel 80c on the proximal end side and driving the rack member 54 by the second pinion 84c. Then, the stent 12 is released quickly, and the procedure can be completed quickly.

  Similar to the first embodiment, also in the second embodiment, the rack member 54 is driven by a plurality of pinions 82 and 84 arranged at intervals in the extending direction of the rack member 54. For this reason, the length L1 of the rack member 54 can be considerably shortened with respect to the required moving distance L3 of the rack member 54. Therefore, it is not necessary to lengthen the rack member 54 even when the long stent 12 or the plurality of stents 12a and 12b (see FIG. 5) arranged in the axial direction are discharged. As a result, the length of the grip 72 can be saved, and the handleability of the grip 72 during the procedure can be improved.

  Further, according to the present embodiment, the speed at which the rack member 54 is moved is different between the first pinion 82 and the second pinion 84. Therefore, by rotating the first pinion 82 or the second pinion 84 according to the speed at which the stent 12 is desired to be released, the release speed of the stent 12 from the outer tube 16 can be easily controlled.

  Further, according to the present embodiment, since the first pinion 82 and the second pinion 84 are arranged on the opposite sides with respect to the rack member 54, the first pinion 82 and the second pinion 84 that are provided in plurality are provided. It can be efficiently arranged in the grip 72.

  Furthermore, according to this embodiment, since the first operation wheel 78 and the second operation wheel 80 are exposed from the grip 72 on different sides, the user can distinguish the first operation wheel 78 and the second operation wheel 80 from each other. Is easy to use.

  In addition, in the second embodiment, for each component common to the first embodiment, it is possible to obtain the same or similar operation and effect as the operation and effect brought about by each common component in the first embodiment. Of course.

  In the configuration shown in FIG. 6, the product of the number of teeth of the second pinion 84 and the module is larger than the product of the number of teeth of the first pinion 82 and the module. The product of the number of teeth and the module may be larger than the product of the number of teeth of the second pinion 84 and the module. In this case, when the first operation wheel 78 provided with the first pinion 82 is rotated, the stent 12 is quickly released, and when the second operation wheel 80 provided with the second pinion 84 is rotated, the stent 12 slowly moves. Released.

  In the configuration shown in FIG. 6, the rack member 54 is provided with a first rack 74 and a second rack 76, and a plurality of first pinions 82 and a plurality of second pinions 84 are arranged on opposite sides of the rack member 54, respectively. However, it may be configured as follows. That is, the rack member 54 may be provided with only one rack, and the plurality of first pinions 82 and the plurality of second pinions 84 may be provided on the same side with respect to the rack member 54. In this case, the plurality of first pinions 82 and the plurality of second pinions 84 are alternately arranged along the axial direction of the rack member 54.

[Third Embodiment]
FIG. 7 is a partially omitted side view of a stent delivery system 90 according to a third embodiment of the present invention. In FIG. 7, the proximal end portion of the inner tube 14 and the grip 92 (housing 50) are indicated by phantom lines. In the stent delivery system 90 according to the third embodiment, elements having the same or similar functions and effects as those of the stent delivery system 10 according to the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. To do.

  The stent delivery system 90 includes a grip 92 having a moving mechanism 52 c for moving the outer tube 16 in the proximal direction with respect to the inner tube 14. The moving mechanism 52 c includes a rack member 54, a plurality (three in the illustrated example) pinions 99, and a plurality (three in the illustrated example) operation wheels 94. The rack member 54 is provided with first and second racks 74 and 76 on opposite sides (upper and lower sides in the illustrated example).

  The plurality of operation wheels 94 are disposed so as to be rotatable at intervals in the extending direction (axial direction) of the rack member 54. The plurality of operation wheels 94 include a first operation wheel 96 that drives the rack member 54 via the first rack 74 and a second operation wheel 98 that drives the rack member 54 via the second rack 76. In the illustrated example, two first operation wheels 96 are provided, and one second operation wheel 98 is provided.

  The first operation wheel 96 and the second operation wheel 98 are exposed on the opposite outer surfaces of the grip 92 (upper surface and lower surface in FIG. 7). Specifically, a plurality of openings 64 are provided on the upper surface of the grip 92 corresponding to the plurality of first operation wheels 96, and the first operation wheels 96 are partially exposed through the openings 64. Further, an opening 64 is provided on the lower surface of the grip 92 corresponding to the second operation wheel 98, and the second operation wheel 98 is partially exposed through the opening 64.

  The first operation wheel 96 is provided with a first pinion 100 that can mesh with the first rack 74. The second operation wheel 98 is provided with a second pinion 102 that can mesh with the second rack 76. The product of the number of teeth of the second pinion 102 and the module is larger than the product of the number of teeth of the first pinion 100 and the module. For this reason, the moving distance of the rack member 54 per unit rotation angle of the second pinion 102 is larger than the moving distance of the rack member 54 per unit rotation angle of the first pinion 100. That is, when the rotation angles are the same, the moving distance of the rack member 54 by driving the second pinion 102 is larger than the moving distance of the rack member 54 by driving the first pinion 100.

  Therefore, when the rotational operation speed for the first operation wheel 96 and the rotational operation speed for the second operation wheel 98 are the same, the outer tube that moves with the rack member 54 when the first operation wheel 96 is rotationally operated. The moving speed of the outer tube 16 that moves together with the rack member 54 is relatively fast when the second operation wheel 98 is rotated.

  In the plurality of first pinions 100, the number of teeth and the module are the same. Although the modules of the first pinion 100 and the second pinion 102 may be the same, in this case, the number of teeth of the second pinion 102 is larger than the number of teeth of the first pinion 100 as shown in FIG. Alternatively, the number of teeth of the first pinion 100 and the number of teeth of the second pinion 102 may be the same, and the module of the second pinion 102 may be larger than the module of the first pinion 100. Alternatively, the number of teeth and the module of the second pinion 102 may be larger than the number of teeth and the module of the first pinion 100, respectively.

  The length of the rack member 54 (the length of the racks 74 and 76) L1 is larger than the center-to-center distance L6 between the first pinions 100. The length L1 of the rack member 54 is greater than the center-to-center distance L7 between the first pinion 100 and the second pinion 102 on the proximal end side. Therefore, within the movable range of the rack member 54, the rack member 54 meshes with at least two pinions adjacent to at least the axial direction of the grip 92 (the extending direction of the rack member 54) among the plurality of pinions 100 and 102. Note that the center-to-center distance L6 between the first pinions 100 and the center-to-center distance L7 between the first pinion 100 and the second pinion 102 on the proximal end side may be the same or different.

  According to the stent delivery system 90 configured in this manner, by rotating the plurality of operation wheels 94 in order from the distal end side, the plurality of pinions 100 and 102 rotate to sequentially move the rack member 54 in the proximal direction. The outer tube 16 can be moved in the proximal direction relative to the inner tube 14. As the outer tube 16 moves in the proximal direction, the stent 12 is gradually released from the distal end side thereof, and at the stage where the rack member 54 moves to the position depicted by the dotted line in FIG. 16 is completely discharged from the tip.

  In this case, since the first operation wheel 96 on the distal end side is rotated and the rack member 54 is moved in the proximal direction at a low speed by the first pinion 100 on the distal end side in the initial release of the stent 12, the stent 12 is released slowly. It is easy to position. As described above, the first pinion 100 on the distal end side functions as an initial release driving rotating body that moves the rack member 54 at the initial release of the stent 12.

  On the other hand, at the end of the release of the stent 12, since the rack member 54 is moved in the proximal direction at a high speed by the second pinion 102 by rotating the second operation wheel 98, the stent 12 is released quickly and the procedure is finished quickly. Can do. As described above, the second pinion 102 functions as an end-release discharge rotor for moving the rack member 54 at the end of the release of the stent 12.

  Similar to the first embodiment, also in the third embodiment, the rack member 54 is driven by a plurality of pinions 100 and 102 arranged at intervals in the extending direction of the rack member 54. For this reason, the length L1 of the rack member 54 can be considerably shortened with respect to the required moving distance L3 of the rack member 54. Therefore, it is not necessary to lengthen the rack member 54 even when the long stent 12 or the plurality of stents 12a and 12b (see FIG. 5) arranged in the axial direction are discharged. As a result, the length of the grip 92 can be saved, and the handleability of the grip 92 during the procedure can be improved.

  Further, according to the present embodiment, since the first operation wheel 96 and the second operation wheel 98 are exposed from the grip 92 on different sides, the user can distinguish the first operation wheel 96 and the second operation wheel 98 from each other. Is easy to use.

  In addition, in the third embodiment, for each component common to the first embodiment, it is possible to obtain the same or similar operation and effect as those provided by the respective common component in the first embodiment. Of course.

  In the configuration shown in FIG. 7, the rack member 54 is provided with a first rack 74 and a second rack 76, and the first pinion 100 and the second pinion 102 are disposed on the opposite sides of the rack member 54. It may be configured as follows. That is, the rack member 54 may be provided with only one rack, and the first pinion 100 and the second pinion 102 may be provided on the same side with respect to the rack member 54.

  In the above description, the present invention has been described with reference to preferred embodiments. However, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention. Yes.

10, 10a, 70, 90 ... stent delivery system 12, 12a, 12b ... stent 14 ... inner tube 16 ... outer tube 18, 72, 92 ... grips 52, 52a-52c ... moving mechanism

Claims (9)

A long inner member;
A sheath disposed on the outer side of the inner member so as to be movable in the axial direction with respect to the inner member;
A self-expandable stent disposed between the inner member and the sheath;
A grip including a moving mechanism for moving the sheath in the axial direction with respect to the inner member,
A stent delivery system that accommodates the stent in the sheath in an initial state and releases the stent into a living body lumen as the sheath moves in the proximal direction relative to the inner member,
The moving mechanism is
A displacement member connected to the sheath and movable in the axial direction of the stent delivery system and extending in the axial direction;
A plurality of drive rotators that are arranged at intervals in the extending direction of the displacement member and move the displacement member in the extending direction as it rotates.
A stent delivery system characterized by the above. The stent delivery system according to claim 1, wherein
A plurality of the stents are arranged side by side along the axial direction of the inner member,
The number of the drive rotating bodies is the same as the number of the stents,
Each time the drive rotator is rotated in order from the distal end side, the stent is released from the sheath in order from the distal end side.
A stent delivery system characterized by the above. The stent delivery system according to claim 1, wherein
The moving distance of the displacement member per unit rotation angle of the drive rotator is different between at least one of the drive rotators and the other drive rotators.
A stent delivery system characterized by the above. The stent delivery system according to claim 1, wherein
The plurality of drive rotators include a plurality of first drive rotators and a plurality of second drive rotators,
At least in the movable range of the displacement member, at least one of the first drive rotator and at least one second drive rotator can drive the displacement member,
The movement distance of the displacement member per unit rotation angle of the plurality of first drive rotators is different from the movement distance of the displacement member per unit rotation angle of the plurality of second drive rotators.
A stent delivery system characterized by the above. The stent delivery system according to claim 4,
The displacement member has first and second driven parts on opposite sides,
The plurality of first drive rotators are in contact with the first driven portion to drive the displacement member,
The plurality of second drive rotators are in contact with the second driven portion to drive the displacement member,
A stent delivery system characterized by the above. The stent delivery system according to claim 5,
Each of the plurality of first rotation operation units rotatably supported by the grip is provided with the first drive rotating body,
Each of the plurality of second rotation operation units rotatably supported by the grip is provided with the second drive rotator.
The plurality of first rotation operation portions and the plurality of second rotation operation portions are exposed on opposite outer surfaces of the grip.
A stent delivery system characterized by the above. The stent delivery system according to claim 1, wherein
The moving distance of the displacement member per unit angle of the driving rotator provided on the most proximal side is larger than the moving distance of the displacement member per unit angle of the driving rotator provided on the most distal side. ,
A stent delivery system characterized by the above. The stent delivery system according to claim 7,
The drive rotator provided on the most distal side is provided in a first rotation operation unit supported rotatably on the grip,
The drive rotator provided on the most proximal side is provided in a second rotation operation unit rotatably supported by the grip,
The first rotation operation unit and the second rotation operation unit are exposed on opposite outer surfaces of the grip.
A stent delivery system characterized by the above. The stent delivery system according to any one of claims 1 to 8,
The position of the displacement member is visible from the outside of the grip.
A stent delivery system characterized by the above.

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