JP4548801B2 - Medical treatment tool for filter recovery - Google Patents

Description

The present invention relates to a filter treatment medical treatment tool for collecting a filter placed in a blood vessel.

Conventionally, a filter placed in the inferior vena cava has been known in order to prevent thrombus, blood clot substance and the like from entering the pulmonary artery. As shown in FIG. 9, the filter 100 has a substantially triangular pyramid shape in which a plurality of support columns 101 are opened in an umbrella shape on the upstream side in the blood flow direction, and at the downstream end (the apex of the triangular pyramid). Is provided with a hook 102.

By the way, the filter 100 needs to be recovered after being left in the body for a certain period. A medical treatment instrument 105 that performs this recovery is known in which a wire having a loop 107 at the tip is inserted into a flexible tube 106. Then, using this medical treatment instrument 105, the loop 107 is engaged with the hook 102 (see FIG. 9A), and the filter 100 is drawn into the flexible tube 106 together with the loop 107. In general, the flexible tube 106 is taken out of the body and collected while being held (see Patent Documents 1 and 2).

However, since the filter 100 is left in the body for a certain period of time, as shown in FIG. 9B, the strut 101 and the hook 102 are buried in the blood vessel wall due to the proliferation of the endothelial cells and the like when collecting. There may be. Therefore, the conventional medical treatment instrument 105 has a problem that when the hook 102 is buried in this manner, the loop 107 cannot be engaged and the recovery is difficult.
Further, the vein is more susceptible to the pulsation caused by the heartbeat than the artery, and the blood vessel repeatedly contracts and deforms toward the inner diameter side in accordance with the pulsation. At the same time, there is a problem that it becomes difficult to form a uniform circular loop and the recovery becomes impossible.
Japanese translation of PCT publication No. 2003-503085 Japanese Patent Laid-Open No. 11-318910

The present invention has been made to solve the above-described problems, and the object thereof is obstructed by the contraction and deformation motion of the blood vessel due to the pulsation even when a part of the filter is buried in the blood vessel wall. Therefore, the filter can be reliably recovered.

[Means of Claim 1]
The medical treatment tool for filter recovery according to claim 1 has a flexible tube and a locking means for locking the filter placed in the blood vessel at the tip, and can be moved forward and backward in the flexible tube. The core material to be inserted and the filter inserted into the flexible tube through the core material and separated from the core material outside the flexible tube and locked by the locking means can be collected. And a capturing tool that is inserted into the flexible tube so as to be able to move forward and backward.

According to this, even when a part of the filter is buried in the blood vessel wall, the filter is locked by the locking means of the core material, and the posture of the filter is controlled by operating the core material. The detention ideal form can be restored. And since the core material is inserted into the loop, the posture of the filter is corrected with the core material, and then the loop is transferred to the core material in a state where the filter is locked and moved forward (moves toward the tip side). Thus, the filter can be reliably captured by the loop, and is not obstructed by the contraction and deformation motion of the blood vessel due to pulsation.

[Means of claim 2]
The medical treatment tool for filter recovery according to claim 2 is the medical treatment tool for filter recovery according to claim 1, further comprising a resin tube between the core material and the loop portion. . Thereby, the resin tube is provided between the core member and the capturing tool including the loop. For this reason, when operating a core material and a capture tool, it does not rub against each other, and advancement / retraction operation of a core material and a capture tool becomes easy.

[Means of claim 3]
The medical device for recovering a filter according to claim 3 is the medical device for recovering a filter according to claim 1 or 2, wherein the core is constituted by a single coil spring body, The locking means is constituted by a gap provided between the strands of the single coil spring body.

[Means of claim 4]
The medical device for recovering a filter according to claim 4 is the medical device for recovering a filter according to claim 1 or 2, wherein the core material is composed of a multi-row coil spring body, The locking means is constituted by a gap provided between the strands of the multi-row coil spring body.

[Means of claim 5]
The medical device for recovering a filter according to claim 5 is the medical device for recovering a filter according to claim 3 or 4, wherein the tip of the core member is formed in a spiral shape or a wave shape. It is characterized by.
Thereby, in addition to the locking of the filter by the locking means, the filter can be entangled with the tip by rotating the tip, and the posture of the filter can be controlled by operating the core member. .

The medical treatment instrument for collecting a filter of the best mode 1 is inserted into a flexible tube so as to be able to advance and retract, and a capturing tool having a loop at the tip, and inserted into the flexible tube so as to be able to advance and retract, and penetrate into the loop. And a core member having a locking means at the tip. The core material locks the filter by the locking means, the capturing tool captures the filter locked by the locking means by the loop, and the flexible tube is moved to the distal end side to loop. The filter captured by is drawn into the tube.
The locking means is a notch that is inclined and opened toward the proximal side in the axial direction on the outer periphery of the tip.

In addition, the flexible tube has a Y-shaped connector at the proximal end, a trapping tool is inserted into one branch pipe divided into two branches of the Y-shaped connector, and a core material is inserted into the other branch pipe. The branch pipe is provided with a locking mechanism for locking the core material.
In addition, an outer-layer flexible tube is provided on the outer periphery of the flexible tube, which is shorter than the flexible tube and is provided so as to be movable forward and backward with respect to the flexible tube. The outer layer flexible tube has a Y-shaped connector at the proximal end, and the flexible tube penetrates into one of the two branched tubes of the outer layer flexible tube. Can inject fluid between the flexible tube and the outer layer flexible tube. Then, when the flexible tube or the outer layer flexible tube is moved to the distal end side, the filter captured by the loop is drawn into the tube.

The medical treatment tool for filter recovery of the best mode 2 includes a flexible resin tube that surrounds the outer periphery of the core and is inserted into the loop.
In the medical treatment tool for filter recovery according to the best mode 3, the tip portion is constituted by a single or multiple coil spring body, and the locking means is a gap provided between the strands of the coil spring body.
The medical treatment tool for filter recovery of the best mode 4 has a distal end formed into a spiral shape or a wave shape.

[Configuration of Example 1]
A configuration of the filter-recovery medical treatment tool 1 (hereinafter referred to as a medical treatment tool 1) according to the first embodiment will be described with reference to FIGS.
The medical treatment instrument 1 includes a flexible flexible tube 2 (hereinafter referred to as a tube body 2), a capture device 3 that is inserted into the tube body 2 so as to be movable back and forth, and a core member 4.

The capturing tool 3 has a loop 31 at the tip, and can capture a filter 5 described later in the loop 31. The loop 31 can be reduced in diameter by a hand operation.
The core material 4 is provided so as to penetrate the loop 31 and is formed of a stainless steel hollow tube. The leading edge 41 is hemispherically welded or brazed. In addition, on the outer periphery of the tip portion 42, two notches 61 and 62 that are inclined toward the axial direction and open toward the hand side are provided as locking means 6 that locks the filter 5.

Specifically, in the present embodiment, one notch 61 is inclined with respect to the axial direction at one end side in the radial direction of the tip end portion 42 and is open to the hand side, and the other notch 62 is A predetermined interval is provided in the axial direction with the notch 61, and the second end side in the radial direction of the tip end portion 42 is inclined with respect to the axial direction and opens toward the proximal side. Further, in order to facilitate the engagement of the filter 5 with the notches 61 and 62, inclined surfaces 61a and 62a are provided on the outer periphery of the distal end portion 42 on the proximal side of the openings of the notches 61 and 62, respectively.
Note that three or more notches may be provided, and the notches may be provided radially at predetermined angular intervals on the outer periphery of the distal end portion 42.

The tubular body 2 has a Y-shaped connector 21 fixed to the proximal end, the trapping tool 3 is inserted into one branch pipe 22 divided into two branches of the Y-shaped connector 21, and a core material is inserted into the other branch pipe 23. 4 is penetrating.
The branch pipe 23 is provided with a lock mechanism 25 that locks the core material 4. The lock mechanism 25 has a cylindrical member 25b with a split groove 25a, and the core member 4 is inserted into the cylindrical member 25b and screwed and tightened from the outer periphery, whereby the split groove 25a of the cylindrical member 25b is closed. The core material 4 and the branch pipe 23 are fixed. That is, the core material 4 and the tube body 2 are fixed.

In addition, the capturing tool 3 pulled out from the branch tube 22 to the proximal side and the core material 4 pulled out from the branch tube 23 to the proximal side have gripping tools 35 and 45 for the operator to grip and operate, respectively. Is provided.
Each of the gripping tools 35 and 45 has a lock mechanism having the same configuration as the lock mechanism 25 described above, and is fixed at an arbitrary position on the capturing tool 3 and the core material 4 by the lock mechanism.

Further, the medical treatment instrument 1 has an outer-layer flexible tube 7 (hereinafter referred to as an outer-layer tube) that is provided on the outer periphery of the tube body 2 so as to be axially shorter than the tube body 2 and to be movable back and forth with respect to the tube body 2. (Referred to as body 7).
The outer tube 7 has a Y-shaped connector 71 at the proximal end, the tube 2 is inserted into one branch pipe 72 divided into two branches of the Y-shaped connector 71, and the tube 2 is inserted into the other branch pipe 73. A syringe 74 for injecting a fluid is connected between the outer tube 7 and the outer layer tube 7. A sealing mechanism for preventing leakage of fluid injected from the syringe 74 is provided between the branch pipe 72 and the pipe body 2.

In this embodiment, for example, the tube 2 has an outer diameter of 3.6 mm and an inner diameter of 2.8 mm, and the outer layer tube 7 has an outer diameter of 4.4 mm and an inner diameter of 3.7 mm. The core 4 is a hollow tube having an outer diameter of 0.6 mm and an inner diameter of 0.4 m, and the notches 61 and 62 each have a notch width of 0.4 mm and an inclination angle α with respect to the axial direction. Is about 15 °, and the interval between the notch 61 and the notch 62 is 4 mm. The inclined surfaces 61a and 62a are provided such that the inclination angle β with respect to the axial direction is about 9 °.

Moreover, it is preferable that the material of the tubular body 2 and the outer layer tubular body 7 is polyamide, polyethylene, fluororesin, or the like. In particular, the outer layer tube body 7 is provided so as to be movable back and forth with respect to the tube body 2, and the tube body 2 and the outer layer tube body 7 slide relative to each other, so that the same kind of resin material is applied to the tube body 2 and the outer layer tube body 7. It is desirable to avoid using it, but as an exception, a combination of polyethylene or PTFE having excellent slidability even with the same material is more desirable and most desirable from the viewpoint of obtaining high slidability. Is a combination of PTFE.

The material of the Y-shaped connectors 21 and 71 is preferably a highly transparent material such as polycarbonate or nylon. In addition, the Y-shaped connectors 21 and 71 may be provided integrally with the proximal ends of the tube body 2 and the outer layer tubular body 7, respectively, and are separate bodies and the proximal ends of the tubular body 2 and the outer layer tubular body 7. It may be screwed and fastened.

[Operation Method of Example 1]
The operation method of the medical treatment tool 1 of Example 1 is demonstrated using FIG.
The medical treatment instrument 1 is used to collect the filter 5 placed in the blood vessel in the inferior vena cava in order to prevent thrombus, blood clot substance and the like from entering the pulmonary artery. The filter 5 has a substantially triangular pyramid shape in which a plurality of support columns 51 are opened in an umbrella shape on the upstream side in the blood flow direction. Here, the state before recovery is indicated by a two-dot chain line in FIG. As shown, the support column 51 and the downstream end 52 (the apex of the triangular pyramid) are buried in the blood vessel wall due to the proliferation of the endothelial cells, and are inclined with respect to the axial direction.

According to the medical treatment instrument 1 of the first embodiment, the filter 5 in which the support column 51 is buried in the blood vessel wall can be collected by the following procedure.
(A) First, the core member 4 is made to reach the vicinity of the filter 5, and the locking means 6 (for example, the notch 61) is engaged with the support column 51 and the end portion 52. Thereafter, the core material 4 is pulled toward the proximal side, the orientation of the filter 5 is directed in the axial direction, the core material 4 is put in a tension state, the core material 4 is locked by the lock mechanism 25, and the tubular body 2, the core material 4, Is fixed (see FIG. 3A).

(B) Next, the capturing tool 3 is advanced to push out the loop 31 from the tip of the tube body 2, and the loop 31 is advanced by using the core material 4 inserted into the loop 31 as a guide, and the outer periphery of the filter 5. (See FIG. 3B).
(C) Next, the lock mechanism 25 is released, the loop body 31 is moved forward, the loop 31 is pulled toward the hand side, and the column 51 of the filter 5 is contracted while the filter 5 is moved together with the loop 31 in the tubular body 2. It clamps in the drawing tube 2 (refer FIG.3 (c)).
(D) Finally, the tube body 2 is taken out of the body, and the recovery of the filter 5 is completed.

In the operation of (c), if the filter 5 is enlarged in diameter and cannot be accommodated in the tube body 2, the outer layer tube body 7 is moved forward to move the filter 5 to the tube body 2 and the outer layer tube body 7. You may store in both (refer FIG.3 (c) two-dot chain line).

[Effects of Example 1]
According to the medical treatment instrument 1 of the first embodiment, even when a part of the column 51 of the filter 5 or the end 52 of the filter 5 is buried in the blood vessel wall, the filter 5 is locked by the locking means 6 of the core member 4. Is locked and in a tensioned state, the posture of the filter 5 can be returned to the original indwelling ideal form (the posture in which the end portion 52 is approximately located at the blood vessel diameter center).

In addition, since the core material 4 is inserted into the loop 31, the posture of the filter 5 is corrected by the core material 4, and then the loop 31 is transmitted to the core material 4 and moved forward while the filter 5 is locked. Thus, the filter 5 can be captured by the loop 31. That is, the loop 31 can be automatically moved to the filter 5 whose posture is already controlled by the core material 4 using the core material 4 as a guide. As a result, the filter 5 can be reliably captured by the loop 31 without being obstructed by the contraction deformation motion of the blood vessel due to pulsation.

In addition, since the lock mechanism 25 that locks the core material 4 is provided on the branch pipe 23 of the Y-shaped connector 21 at the proximal end, the tension state of the core material 4 can be created by the hand operation. In the state where the filter 5 is locked, the loop 31 is transmitted to the core member 4 and moved forward to easily capture the filter 5. In the first embodiment, the lock mechanism 25 includes a cylindrical member 25b with a split groove 25a, and the core member 4 is inserted into the cylindrical member 25b and locked by being screwed and tightened from the outer periphery. Since it is a structure, the tension | tensile_strength state of the core material 4 can be created easily by screwing and fastening by hand.

In addition, by providing the outer layer tubular body 7, when the filter 5 is captured and the tubular body 2 is advanced and retracted, even when the diameter of the filter 5 is increased, the outer layer tubular body 7 can be retracted by being advanced. Become.
Furthermore, since fluid can be injected between the tube body 2 and the outer layer tube body 7, for example, by injecting physiological saline between the tube body 2 and the outer layer tube body 7, the tube body 2. It is possible to prevent clots from accumulating between the outer tube 7 and the outer tube 7 and to smoothly move the tube 2 and the outer tube 7 back and forth.

The configuration of the medical treatment tool 1 according to the second embodiment will be described with reference to FIG. 4 with a focus on differences from the first embodiment.
The medical treatment instrument 1 of the present embodiment includes a flexible resin tube 8 that surrounds the outer periphery of the core member 4 and is inserted into the loop 31. As a material of the resin tube 8, for example, polyethylene, or a fluororesin such as PTFE or PFA is desirable. The dimensions are, for example, an inner diameter of 1 mm and an outer diameter of 1.6 mm.

According to this, since the resin tube 8 is provided between the core material 4 and the capturing tool 3 including the loop 31, when the core material 4 and the capturing tool 3 are operated, metals that are the same kind of materials are connected to each other. The core material 4 and the capturing tool 3 can be easily moved back and forth without rubbing each other.

The configuration of the medical treatment tool 1 according to the third embodiment will be described with reference to FIG.
In the medical treatment instrument 1 of the present embodiment, the distal end portion 42 is constituted by a single coil spring body, and the locking means 6 is a gap 64 provided between the strands of the coil spring body.

Specifically, the tightly wound portion and the loosely wound portion are provided at the tip portion 42, and a plurality of gaps 64 are continuously provided in the loosely wound portion (see FIG. 5A).
In this embodiment, for example, a wire rod having a wire diameter of 0.2 mm is formed by winding to an outer diameter of 0.6 mm, and the gap 64 is provided by setting the coil pitch of the loosely wound portion to 4 mm. At this time, it is preferable that the inclination angle of the strands is substantially matched with the inclination angle of the column 51 of the filter 5.

In addition, if the coil spring body has a structure having a tightly wound portion and a loosely wound portion as in this embodiment, the coil spring body has a spring constant higher than that of the coil spring body having only tightly wound portions, The elongation of the coil spring body due to the load can be kept low.
Further, as shown in FIG. 5B, the locking means 6 may be formed by providing a gap 65 by partially widening the strands so as to be inclined toward the axial direction and open toward the hand side. .

Thereby, the attitude | position of the filter 5 is controllable by hooking the support | pillar 51 and the edge part 52 of the filter 5 to the clearance gaps 64 and 65, and operating the core material 4. FIG.

The configuration of the medical treatment tool 1 according to the fourth embodiment will be described with reference to FIG.
In the medical treatment instrument 1 of the present embodiment, the distal end portion 42 is constituted by a multi-element coil spring body, and the locking means 6 is a gap 66 provided between the strands of the coil spring body.
In this embodiment, for example, two wires having a wire diameter of 0.2 mm are formed by winding them to an outer diameter of 0.6 mm, and the gap 66 is provided by setting the coil pitch to 6 mm. Moreover, you may form by twisting two wires so that a twist pitch may be 6 mm using a rope twisting machine. That is, seven wires with an outer diameter of 0.2 mm, one of which is a core wire and six of which are twisted as side wires, leaving two adjacent side wires, and other side wires and core wires. It is a missing structure. In addition, it is preferable to make the twist angle substantially coincide with the inclination angle of the column 51 of the filter 5.

Thereby, the attitude | position of the filter 5 is controllable by hooking the support | pillar 51 and the edge part 52 of the filter 5 to the gap | interval 66, and operating the core material 4. FIG.

The configuration of the medical treatment instrument 1 according to the second embodiment will be described with reference to FIG.
In the medical treatment instrument 1 of the present embodiment, the distal end portion 42 is formed in a spiral shape (see FIG. 7A) or a wave shape (see FIG. 7B). Specifically, the tip portion 42 is molded by being heat-treated at about 800 ° C. while being set in a spiral or wave-shaped mold. Moreover, in order to eliminate the discoloration by heat processing, it forms by performing an electropolishing process after heat processing as needed.

Thereby, in addition to the locking of the filter 5 by the locking means 6, the filter 5 can be entangled with the tip 42 by rotating the tip 42, and by operating the core member 4, the filter 5 The attitude can be controlled.

[Modification]
In the medical treatment instrument 1 according to the first embodiment, the core material 4 is formed of a hollow tube body, but only the distal end portion 42 is formed of a hollow tube body. 8 (a) and 8 (c)) or a stranded wire structure 47 (see FIG. 8 (d)).
The single wire 46 is, for example, a stainless steel wire or an Ni—Ti wire having an outer diameter of 0.3 to 0.6 mm.

The stranded wire structure 47 is formed by, for example, twisting seven wires having an outer diameter of 0.2 mm, one of which is a core wire and six of which are side wires. In addition, the material of the wire which forms the twisted wire structure 47 is a stainless steel wire or a Ni-Ti wire. Further, a stainless steel wire may be used for a part of the seven wires, and a Ni—Ti wire may be used for the rest.
Further, the stranded wire structure 47 may be formed by twisting 12 strands having an outer diameter of 0.15 mm as side strands around the outer periphery of a core wire having an outer diameter of 0.3 mm. According to this, by increasing the outer diameter of the core wire and reducing the outer diameter of the side line, the operability of the push-pull operation can be further improved while maintaining flexibility.

Furthermore, in the medical treatment instrument 1 of Examples 3 and 4, the proximal side of the distal end portion 42 of the core material 4 may be configured with the single wire 46 and the stranded wire structure 47 as described above, and the hollow tube body It may be configured.
In addition, when comprised with a hollow tube body, a hollow tube body is formed with an outer diameter of 0.6 mm and an inner diameter of 0.4 mm, for example with stainless steel or a Ni-Ti wire.

Moreover, although the medical treatment tool 1 of Example 1 was provided with the outer layer tubular body 7, since it is used as needed, it does not necessarily need to be provided with the outer layer tubular body 7.

(A) is the whole block diagram of a medical treatment tool, (b) is sectional drawing perpendicular | vertical to the axial direction of the front-end | tip part of a medical treatment tool, (c) is the axis | shaft of the front-end | tip part of a medical treatment tool. It is sectional drawing parallel to a direction (Example 1). (A) is a top view of the front-end | tip part of a core material, (b) is a side view of the front-end | tip part of a core material (Example 1). (Example 1) which is explanatory drawing of the operation method of a medical treatment tool. (A) is sectional drawing perpendicular | vertical to the axial direction of the front-end | tip part of a medical treatment tool, (b) is sectional drawing parallel to the axial direction of the front-end | tip part of a medical treatment tool (Example 2). (Example 3) which is a side view of the front-end | tip part of a core material. (A) is a side view of the front-end | tip part of a core material, (b) is a cross section perpendicular | vertical to the axial direction of (a) (Example 4). (A) is a perspective view of the front-end | tip part of the core material shape | molded by spiral shape, (b) is a perspective view of the front-end | tip part of the core material shape | molded by the waveform (Example 5). (A) is a side view of a core material, (b) is an AA cross section of (a), (c) is a BB cross section of (a), and (d) is a side surface of the core material. It is a figure (modification). (A) is explanatory drawing of the conventional medical treatment tool, (b) is explanatory drawing of the filter buried in the blood vessel wall (conventional example).

1 Medical treatment tool (medical treatment tool for filter recovery)
2 Tube (Flexible tube)
21 Y-shaped connector 22 Branch pipe 23 Branch pipe 25 Lock mechanism 3 Trapping tool 31 Loop 4 Core material 42 Tip portion 5 Filter 6 Locking means 62, 62 Notches 64-66 Gap 7 Outer layer tube (outer layer flexible tube)
71 Y-shaped connector 72 Branch pipe 73 Branch pipe 8 Resin tube

Claims (5)

A flexible tube;
A core member having a locking means for locking the filter placed in the blood vessel at the tip, and inserted into the flexible tube so as to freely advance and retract;
Inside the flexible tube, there is a loop portion at the tip that can penetrate the core material and collect the filter that is separated from the core material and locked by the locking means outside the flexible tube. A medical device for collecting a filter, comprising: a capture device that is inserted into the flexible tube so as to be able to advance and retreat. The medical treatment tool for filter recovery according to claim 1, further comprising a resin tube between the core material and the loop portion. The core material is composed of a single coil spring body,
3. The filter recovery medical treatment tool according to claim 1, wherein the locking means is constituted by a gap provided between the strands of the single coil spring body. The core material is composed of multiple coil spring bodies,
The medical treatment tool for filter recovery according to claim 1 or 2, wherein the locking means is configured by a gap provided between the strands of the multiple coil spring body. The medical treatment tool for filter recovery according to claim 3 or 4, wherein a distal end portion of the core member is formed in a spiral shape or a wave shape.

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