JP7137933B2 - filter device - Google Patents

Description

The present invention relates to a filter device that is inserted into a biological lumen.

For example, a blood clot in part of a vein can cause pain and swelling. For this treatment, there is a method of physically removing the thrombus by percutaneously inserting a device into the body lumen. During such treatment, pulmonary embolism may occur if a thrombus that has completely or partially detached from the vessel wall enters the blood stream and reaches the lungs. Therefore, when performing such treatment, a thrombolytic agent is used before, during and/or after the treatment, and as much exfoliated thrombus as possible is aspirated and removed during the treatment. However, even with such treatment, a clinically undesirable sized exfoliated thrombus may reach the lungs and the like.

In order to avoid such pulmonary embolism, a method is known in which a filter is placed in the blood vessel to collect thrombi flowing through the blood vessel. For example, Patent Document 1 describes a device in which a mesh-like filter centered on the wire is fixed to the distal portion of an elongated wire. The wire in this device can be used as a guidewire. Thus, the wire can lead to the filter, for example, a catheter for aspiration of collected thrombus or the like.

US Patent Application Publication No. 2004-0102807

As the catheter moves along the wires of the filter device, the wires tend to move with them under the influence of frictional resistance and the like. As a result, the filter fixed to the wire may move from its indwelling position. If the filter moves from the indwelling position, there is a possibility that collected matter may be washed away or the living tissue in which the filter is indwelled may be damaged.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and aims to provide a filter device capable of suppressing outflow of collected matter collected in the filter and damage to living tissue in which the filter is placed. aim.

A filter device for achieving the above object is a filter device for collecting objects in a biological lumen, comprising a long wire and a shaft portion having a locking portion fixed to a distal portion of the wire; an expandable filter comprising a distal opening and a proximal opening, the wire being passable through the distal opening and the proximal opening; a portion positionable between the distal opening and the proximal opening and passable through either one of the distal opening and the proximal opening; The opening and the locking portion are connectable, and the portion of the filter that is connected to the proximal opening is formed in a net shape so as to be able to collect the object. At least one of the position side openings can be flared radially outward to increase the inner diameter .
Another aspect of a filter device for achieving the above object is a filter device for collecting objects within a biological lumen, comprising a long wire and a locking portion fixed to a distal portion of the wire. and an expandable filter with distal and proximal openings, the wire being passable through the distal and proximal openings. , the locking portion can be positioned between the distal opening and the proximal opening and can pass through either one of the distal opening and the proximal opening; The proximal side opening and the locking portion are connectable, and the portion of the filter connected to the proximal side opening is formed in a net shape so as to be able to collect the object, and the distal side At least one of the opening and the proximal opening has an inner guiding portion, which is an axially extending concave portion or a convex portion, on the inner peripheral surface, and the locking portion is an axially extending convex portion or concave portion. An outer guide portion is provided on the outer peripheral surface, the outer guide portion being axially passable through at least one of the distal opening and the proximal opening along the inner guide portion.

In the filter device configured as described above, the locking portion can pass through at least one of the distal side opening and the proximal side opening, so the shaft portion can move long with respect to the filter. Therefore, even if the shaft receives force from the medical device and moves in the axial direction when another medical device is moved along the wire, the force is less likely to act on the filter. Therefore, the filter placed in the biological lumen can be properly maintained. Therefore, it is possible to suppress the outflow of collected matter from the filter and damage to the biological tissue in which the filter is placed.

It is a top view showing a filter device concerning a 1st embodiment. Fig. 3 is an enlarged cross-sectional view of the distal portion of the filter device; 3A is a cross-sectional view taken along line AA of FIG. 2, and FIG. 4B is a cross-sectional view taken along line BB of FIG. 2, showing the distal portion of the filter device. FIG. 3 is a cross-sectional view showing the state of the inside of a blood vessel, where (A) is the state when the filter device is inserted into the blood vessel, (B) is the state where the filter is expanded inside the blood vessel, and (C) is the crushing device inside the blood vessel. It shows the state inserted in the . FIG. 10 is a cross-sectional view showing the distal portion of the filter device within a blood vessel; It is a flowchart explaining the procedure using a filter device. FIG. 11 is a cross-sectional view showing a distal portion of a filter device according to a second embodiment; FIG. 8 is a view showing the distal portion of the filter device, (A) is a cross-sectional view along line CC in FIG. 7, and (B) is a distal opening and a locking portion passing through the distal opening. It is a cross-sectional view showing the. FIG. 10 is a cross-sectional view explaining the action of the filter device according to the second embodiment; FIG. 11 is a plan view showing a distal portion of a filter device according to a third embodiment; 11A is a cross-sectional view taken along line DD of FIG. 10, and FIG. 11B is a cross-sectional view showing a locking portion passing through the distal opening. FIG. FIG. 11 is a cross-sectional view showing a distal portion of a filter device according to a fourth embodiment; FIG. 10 is a cross-sectional view showing a modification of the filter device; FIG. 11 is a cross-sectional view showing another modification of the filter device;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the dimensional ratios in the drawings may be exaggerated for convenience of explanation and may differ from the actual ratios.
<First embodiment>

A filter device 10 according to a first embodiment of the present invention is used to collect objects flowing through blood vessels. For example, the filter device 10 collects objects such as thrombi, plaques, and calcified lesions that have detached from the vessel wall inside the vessel. In this specification, the side of the device that is inserted into a blood vessel is called the "distal side", and the hand side of the device that is operated is called the "proximal side". In addition, objects to be collected are not necessarily limited to thrombi, plaques, and calcified lesions, and all objects that can exist within a living body lumen can be applicable. In addition, in this specification, the source side of blood flow in a blood vessel is referred to as "upstream side", and the side to which blood flow is directed is referred to as "downstream side".

1 to 3, the filter device 10 according to the first embodiment includes a filter 20, which is a net-like tubular body, and an elongated shaft portion 30 connected to the filter 20. As shown in FIGS.

Shaft portion 30 includes wire 31 , locking portion 32 and distal end portion 33 . The wire 31 is a long wire extending from the hand to the filter 20 . The locking portion 32 is a tubular member fixed to the outer peripheral surface of the distal portion of the wire 31 . The locking portion 32 has an outer diameter larger than that of the wire 31 . Note that the shape of the locking portion 32 is not particularly limited. Distal end 33 has a larger outer diameter than wire 31 . Therefore, the distal end 33 can safely come into contact with living tissue.

The constituent material of the wire 31 is preferably a flexible material, such as a shape memory alloy, stainless steel, tantalum (Ta), titanium (Ti), and platinum, to which a shape memory effect or superelasticity is imparted by heat treatment. (Pt), gold (Au), tungsten (W), polyolefins such as polyethylene and polypropylene, polyesters such as polyamide and polyethylene terephthalate, fluorine-based polymers such as ETFE (tetrafluoroethylene-ethylene copolymer), PEEK (polyether ether ketone), polyimide, and the like can be preferably used. As the shape memory alloy, a Ni--Ti system, a Cu--Al--Ni system, a Cu--Zn--Al system, or a combination thereof is preferably used. Examples of structures that combine a plurality of materials include a structure in which a core wire made of Pt is coated with a Ni—Ti alloy to provide contrast, and a structure in which a core wire made of a Ni—Ti alloy is plated with gold. .

The constituent materials of the locking portion 32 and the distal end portion 33 are not particularly limited. For example, stainless steel can be suitably used.

The filter 20 includes an expansion part 40 that is a net-like tubular body, a distal opening 50 and a proximal opening 60 . The extension part 40 has a plurality of filamentous bodies 41 that are braided in a net shape so as to form a cylindrical body. Each linear body 41 is elastically deformable. The extension part 40 has a gap 42 between the braided linear bodies 41 .

Distal opening 50 is a tubular body to which the distal end of extension 40 is fixed. The distal opening 50 holds the ends of the plurality of braided flexible linear bodies 41 in a tubular shape. As shown in FIGS. 2 and 3A, the wire 31 is movably passed through the lumen of the distal opening 50 . The inner diameter of distal opening 50 is larger than the outer diameter of wire 31 and the outer diameter of locking portion 32 . Therefore, the locking portion 32 can pass through the lumen of the distal opening 50 in the axial direction.

The proximal opening 60 is a tubular body to which the proximal end of the extension 40 is fixed. The proximal side opening 60 holds the ends of the plurality of braided flexible linear bodies 41 in a tubular shape. As shown in FIGS. 2 and 3B, the wire 31 is movably passed through the lumen of the proximal opening 60 . The proximal opening 60 is positioned closer to the proximal side than the locking portion 32 . The inner diameter of the proximal opening 60 is larger than the outer diameter of the wire 31 and smaller than the outer diameter of the locking portion 32 . Therefore, the locking portion 32 cannot pass through the lumen of the distal opening 50 to the proximal side along the axial direction.

The constituent materials of the proximal side opening 60 and the distal side opening 50 are not particularly limited. For example, stainless steel can be suitably used.

The outer diameter of the locking portion 32 is not particularly limited. For example, it is 0.1 to 2.0 mm. The outer diameters of the proximal opening 60 and the distal opening 50 are not particularly limited. For example, it is 0.3 to 3.0 mm. The inner diameter of the proximal opening 60 is not particularly limited. For example, it is 0.1 to 2.5 mm. The inner diameter of the distal opening 50 is not particularly limited. For example, it is 0.1 to 2.5 mm.

As shown in FIGS. 1 and 2, the expanded portion 40 expands in diameter by the elastic force (restoring force) of the linear body 41 itself in a natural state where no external force acts, and is folded back in the axial direction. Become. Extension 40 includes an outer portion 43 connected to distal opening 50 and an inner portion 44 connected to proximal opening 60 . In the folded state, the inner portion 44 is recessed inside the outer portion 43 . That is, the extension 40 is pre-shaped to have such a shape. Shaping can be performed, for example, by holding a predetermined shape, housing it in a mold, and heating it. The inside of the extension portion 40 is a region surrounded by the inner surface of the extension portion 40 and the central axis. The inner surface of the extension part 40 means the inner surface of a cylindrical body formed by braiding the linear body 41 . A linear body 41 positioned at the distal portion of the extension 40 forms a concave outer portion 43 that opens proximally. The filamentous body 41 located at the proximal portion of the extension portion 40 forms a concave inner portion 44 that opens proximally on the inner surface side of the outer portion 43 . The outer portion 43 and the inner portion 44 are connected by an annular folded portion 45 protruding proximally of the extension portion 40 . As a result, the proximal inner portion 44 of the expanded portion 40 is positioned inside the distal outer portion 43, and the expanded portion 40 is folded back in the axial direction. The inner portion 44 has a concave shape that opens to the proximal side, so that an object such as a thrombus flowing along with the blood can be well collected. The extension 40 need not be axially folded or shaped.

As shown in FIG. 4A, the expansion part 40 is elastically deformed to be in a contracted state with a small outer diameter by being accommodated in the sheath 70 (another medical device). The proximal opening 60 and the distal opening 50 move apart when the extension 40 is in its contracted state. By varying the distance between proximal opening 60 and distal opening 50, the outer diameter of braided extension 40 can be varied. In the contracted state, the inner section 44 is located proximal to the outer section 43, rather than inside.

When the expanded portion 40 changes from the contracted state to the folded state, the proximal side opening 60 and the distal side opening 50 approach each other as shown in FIG. 4(B). By varying the distance between proximal opening 60 and distal opening 50, the outer diameter of braided extension 40 can be varied.

The expansion part 40 is indwelled in a blood vessel in a shape close to its natural state. In practice, the expansion part 40 is left in the blood vessel wall in a radially contracted state to some extent from the natural state so as to generate a pressing force against the blood vessel wall by its own expansion force.

The number of linear bodies 41 is not particularly limited, but is, for example, 4-72. Further, the braiding conditions of the linear body 41 are not particularly limited. The outer diameter of the linear body 41 can be appropriately selected depending on the material of the linear body 41 and the application of the filter 20, and is, for example, 20 to 300 μm.

The constituent material of the linear body 41 is preferably a flexible material, and the material applicable to the wire 31 described above can be preferably used.

The maximum outer diameter of the expanded portion 40 in the folded state can be appropriately selected according to the inner diameter of the applied blood vessel. For example, 1 to 40 mm. The outer diameter of the expanded portion 40 in the contracted state can be appropriately selected according to the inner diameter of the applied blood vessel. For example, 0.3 to 4.0 mm. The length of the filter 20 in the folded state in the axial direction can be appropriately selected according to the blood vessel to which it is applied. For example, 20-150 mm.

Next, an example of how to use the filter device 10 according to this embodiment will be described with reference to the flowchart shown in FIG. Here, a case of crushing and collecting a thrombus (object) in a blood vessel (biological lumen) will be described as an example.

First, as shown in FIG. 4(A), the filter device 10 is inserted into a blood vessel while being accommodated in the sheath 70 . Extension 40 is contracted inside sheath 70 . The insertion position into the blood vessel is on the upstream side (proximal side) of the lesion where the thrombus of the blood vessel is provided. Next, the filter device 10 is made to reach the downstream side (distal side) of the thrombus (step S10).

Next, the sheath 70 is moved to the proximal side while restraining the movement of the tubular pressing shaft 71 arranged inside the sheath 70 by hand. At this time, the distal end of the pressing shaft 71 contacts the proximal opening 60 . As a result, movement of the filter 20 is suppressed, and the filter 20 is released from the sheath 70 as shown in FIG. 4(B). As a result, the filter 20 is left in the blood vessel (step S11). The push shaft 71 may not be used. As filter 20 is released from sheath 70 , proximal opening 60 moves closer to distal opening 50 . Then, the expanding portion 40 expands due to its own restoring force and comes into contact with the inner wall surface of the blood vessel. As a result, the extended portion 40 is folded back at the folded portion 45 . Since the expanded portion 40 is formed in a mesh shape, it bites into the inner wall surface of the blood vessel and is firmly fixed. The maximum expandable diameter of the filter 20 used is larger than the vessel diameter into which it is inserted. Therefore, the expansion portion 40 is not completely expanded within the blood vessel, and is effectively fixed to the blood vessel wall by generating expansion force. It should be noted that the extended portion 40 does not need to be folded back just by being released from the sheath 70 . In this case, pushing shaft 71 or sheath 70 is moved distally, and the distal end of pushing shaft 71 or sheath 70 pushes proximal opening 60 or extension 40 distally. As a result, the inner portion 44 moves inside the outer portion 43, and the extension portion 40 is folded back. The locking portion 32 is preferably located between the proximal opening 60 and the distal opening 50, but is not limited to this.

Next, the pressing shaft 71 is withdrawn from the living body, leaving the sheath 70 in place. Next, as shown in FIG. 4(C), a crushing device 80 (medical device) for crushing the thrombus is caused to reach the distal side of the thrombus along the wire 31 . The crushing device 80 includes a crushing part 81 made of a wire capable of crushing a thrombus. When the crushing device 80 is moved along the wire 31, the wire 31 receives force from the crushing device 80 due to frictional resistance or the like. As a result, shaft portion 30 may move distally. However, as shaft portion 30 moves distally, locking portion 32 can move distally through the lumen of distal opening 50 . Therefore, the distance that the shaft portion 30 can move in the axial direction without interfering with the filter 20 is long. Therefore, the distal opening 50 can be prevented from moving due to force from the locking portion 32, and the filter 20 can be maintained in an appropriate state. Therefore, it is possible to suppress the movement of the filter 20 with respect to the indwelling living tissue, thereby suppressing damage to the living tissue.

Next, the crushing device 80 crushes the thrombus. First, the locking portion 32 is arranged on the distal side of the distal opening 50 (step S12). When locking portion 32 is inside extension 40, ie between distal opening 50 and proximal opening 60, wire 31 is manipulated to move shaft portion 30 distally. As a result, the locking portion 32 provided on the shaft portion 30 passes through the lumen of the distal side opening 50 and moves to the distal side of the distal side opening 50 . Note that the locking portion 32 may be positioned between the distal opening 50 and the proximal opening 60 during crushing.

Next, while rotating the crushing part 81, the crushing device 80 is moved proximally. The crushing unit 81 contacts the thrombus while rotating and crushes the thrombus (step S13). As shown in FIG. 5, the crushed thrombus 200 flows with the blood flow and is collected by the expansion part 40 (step S14). At this time, the locking portion 32 is located on the distal side of the distal opening 50 . When crushing device 80 is moved proximally, wire 31 receives force from crushing device 80 due to frictional resistance or the like. Therefore, the shaft portion 30 may move proximally. However, as shaft portion 30 moves proximally, locking portion 32 passes through the lumen of distal opening 50 and extends proximally of distal opening 50 , i.e., inside extension 40 . can move to Therefore, the distance that the shaft portion 30 can move in the axial direction without interfering with the filter 20 is long. Therefore, the distal opening 50 can be prevented from moving due to force from the locking portion 32, and the filter 20 can be maintained in an appropriate state. Therefore, it is possible to suppress the outflow of the thrombus 200 that is collected by the filter 20 and damage to the living tissue in which the filter 20 is placed. Moreover, even for a lesion with a length of about 200 mm, such as deep vein thrombosis, the crushing device 80 can be operated without affecting the filter 20 .

After that, the crushing device 80 is withdrawn from the living body. Sheath 70 is then moved distally along wire 31 . At this time, the wire 31 receives force from the sheath 70 due to frictional resistance or the like. This may cause shaft portion 30 to move distally. However, as shaft portion 30 moves distally, locking portion 32 can move distally through the lumen of distal opening 50 . Therefore, the distal opening 50 can be prevented from moving due to force from the locking portion 32, and the filter 20 can be maintained in an appropriate state. Therefore, it is possible to suppress the outflow of the thrombus 200 that is collected by the filter 20 and damage to the living tissue in which the filter 20 is placed.

Thereafter, a syringe or the like is connected to the hub on the proximal side of the sheath 70, and the inside of the sheath 70 is brought into a negative pressure state. As a result, the destroyed thrombus 200 can be aspirated from the distal opening of the sheath 70 and discharged into the syringe (step S15).

After the sheath 70 completes aspiration of the thrombus 200, the sheath 70 is pushed distally. At this time, the shaft portion 30 may be pulled proximally. This brings the locking portion 32 into contact with the distal portion of the proximal opening 60 . Since the locking portion 32 cannot pass through the lumen of the proximal opening 60, it is possible to prevent the proximal opening 60 from escaping to the distal side. Therefore, the extension 40 is housed inside the sheath 70 from the proximal opening 60 . At this time, the extension portion 40 changes from the folded state to the contracted state. After that, the filter device 10 is removed from the blood vessel together with the sheath 70, and the treatment is completed (step S16).

As described above, the filter device 10 according to the present embodiment is a filter device 10 for collecting a thrombus 200 (object) in a blood vessel (biological lumen), and includes the long wire 31 and the wire 31 and an expandable filter 20 with a distal opening 50 and a proximal opening 60, wherein the wire 31 extends distally. Passable through distal opening 50 and proximal opening 60, lock 32 is positionable between distal opening 50 and proximal opening 60 and through distal opening 50 and proximal opening 60. It can pass through part 50 .

In the filter device 10 configured as described above, the locking portion 32 can pass through the distal opening 50 , so the shaft portion 30 can move long with respect to the filter 20 . Therefore, when other medical devices (the sheath 70, the crushing device 80, etc.) are moved along the wire 31, even if the shaft portion 30 receives force from the medical device and moves in the axial direction, the filter 20 does not receive the force. is difficult to work. Therefore, the filter 20 placed in the blood vessel can be properly maintained. Therefore, it is possible to suppress outflow of collected matter from the filter 20 and damage to the living tissue in which the filter 20 is placed.

The locking portion 32 is also axially passable through the distal opening 50 . This allows shaft portion 30 to move axially through distal opening 50 under force from other medical devices moving along shaft portion 30 . Therefore, the filter 20 placed in the biological lumen can be properly maintained.

Also, the inner diameter of the distal opening 50 is larger than the outer diameter of the locking portion 32 . This allows the locking portion 32 to pass through the distal opening 50 well.

The present invention also provides a mesh-like shaft portion 30 comprising an elongated wire 31 and a locking portion 32 fixed to the distal portion of the wire 31, and a distal opening 50 and a proximal opening 60. thrombus in a blood vessel (biological lumen) using the filter device 10 having a filter 20 having a tubular body of which the shaft portion 30 passes through the distal side opening 50 and the proximal side opening 60 It also has a collection method for collecting 200 (objects). The collection method includes step S11 of placing the filter 20 in the blood vessel, and passing the locking portion 32 positioned between the distal side opening 50 and the proximal side opening 60 through the distal side opening 50. , and steps S13 and S15 of moving other medical devices (sheath 70, crushing device 80, etc.) along the wire 31.

In the collection method configured as described above, the locking portion 32 can pass through the distal opening 50, so the shaft portion 30 can move long with respect to the filter 20. FIG. Therefore, when another medical device is moved along the wire 31 , even if the shaft portion 30 receives force from the medical device and moves in the axial direction, the force is less likely to act on the filter 20 . Therefore, the filter 20 placed in the blood vessel can be properly maintained. Therefore, it is possible to suppress outflow of collected matter from the filter 20 and damage to the living tissue in which the filter 20 is placed.
<Second embodiment>

A filter device 90 according to the second embodiment differs from the first embodiment only in a distal opening 100 and a locking portion 110, as shown in FIGS. 7 and 8A.

The distal opening 100 has an inner guiding portion 101, which is a groove-shaped concave portion extending in the axial direction, on the inner peripheral surface. The locking portion 110 has an outer guide portion 111, which is a convex portion extending in the axial direction, on its outer peripheral surface. The outer guide portion 111 can pass axially through the lumen of the distal opening 100 along with the inner guide portion 101 . It should be noted that the locking portion 110 cannot pass through the lumen of the proximal opening 60 in the axial direction.

If the circumferential position of the outer guiding portion 111 of the locking portion 110 does not match the circumferential position of the inner guiding portion 101 of the distal opening 100 , the locking portion 110 may be positioned at the distal opening 100 . It is not axially passable through the lumen. As shown in FIG. 8(B), only when the position of the outer guiding portion 111 of the locking portion 110 in the circumferential direction matches the position of the inner guiding portion 101 of the distal opening 100 in the circumferential direction, the locking is performed. Portion 110 can pass axially through the lumen of distal opening 100 . Therefore, by manually adjusting the rotational position of the shaft portion 30 with respect to the filter 20 , it is possible to arbitrarily control whether or not the locking portion 32 can pass through the distal opening portion 100 .

Therefore, until the filter 20 is indwelled in the blood vessel, for example, as shown in FIGS. It can be positioned between the distal opening 100 and the proximal opening 60 . As a result, the filter 20 and the shaft portion 30 are not separated from each other during transportation, and the operation is easy. After the filter 20 is indwelled in the blood vessel, the locking portion 110 is put into a state in which it can pass through the lumen of the distal opening 100, as shown in FIG. 8(B). This allows shaft portion 30 to move distally relative to filter 20 . Therefore, even if the shaft portion 30 receives force from another medical device such as the crushing device 80 and moves distally, the locking portion 110 can pass through the distal side opening 100 in the axial direction. Therefore, it is possible to prevent the distal opening 100 from moving due to the force from the locking portion 110 . Therefore, the filter 20 placed in the blood vessel can be maintained in an appropriate state. Also, when crushing while moving the crushing device 80 to the proximal side, as shown in FIG. The lumen of the portion 100 is made impassable. As a result, when the shaft portion 30 moves proximally due to frictional resistance received from the crushing device 80 or the like, the locking portion 110 hits the distal side opening portion 100 . Since locking portion 110 cannot pass through distal opening 100, distal opening 100 moves proximally. At this time, the distal portion of the expansion portion 40 is braided so that its diameter decreases toward the distal side. Therefore, when the distal opening 100 moves proximally, the distal portion of the expansion portion 40 expands in diameter. Therefore, the holding force of the expanded portion 40 on the blood vessel is increased. Therefore, it is possible to prevent the filter 20 from receiving force from the shaft portion 30 and moving to the proximal side.

In addition, the inner guiding portion 101 may be a convex portion instead of a concave portion, and the outer guiding portion 111 may be a convex portion instead of a concave portion.
<Third Embodiment>

A filter device 120 according to the third embodiment, as shown in FIGS. 10 and 11(A), differs from the first embodiment only in a distal opening 130 and an extension part 140 .

The distal opening 130 has a plurality (four in this embodiment) of divisions 131 arranged in the circumferential direction. As shown in FIG. 11(B), the plurality of divided portions 131 are arranged in a ring in contact with each other to form one tubular body. The inner diameter of the distal opening 130 when one tubular body is constructed is smaller than the outer diameter of the locking portion 32 . In the natural state where no external force acts on the extension part 140, the split parts 131 fixed to the distal end are spaced apart in the circumferential direction as shown in FIG. 11(A). The space between the plurality of divisions 131 in the natural state has a size through which the engaging portion 32 can pass.

When the filter device 120 is accommodated in the sheath 70, the plurality of divided portions 131 are brought into contact as shown in FIG. 11(B). At this time, the locking portion 32 cannot pass through the lumen of the distal opening 130 . When the filter device 120 is released from the sheath 70, as shown in FIGS. 10 and 11(A), the elastic force (restoring force) of the expanded portion 140 causes the divided portion 131 to move radially outward. Leave. This allows the locking portion 32 to pass through the lumen of the distal opening 130 . Thus, when filter device 120 is within sheath 70 , locking portion 32 can be better positioned between distal opening 130 and proximal opening 60 . By ejecting the filter 20 from the tubular body such as the sheath 70 , the locking portion 32 can pass through the distal opening 130 .

In addition, the distal portion of the expansion portion 140 is open to the outer diameter in the radial direction in the natural state because the divided portions 131 arranged at intervals in the circumferential direction are fixed. Therefore, the extended portion 140 can be set to have a longer axial length L in contact with the living tissue than in the case where an undivided tubular distal opening is fixed. Therefore, it is possible to improve the holding force of the extended portion 140 on the living tissue.

Note that the structure including the dividing portion 131 may be provided at the proximal opening. Also, the structure comprising split 131 may be provided at both the distal and proximal openings.
<Fourth Embodiment>

A filter device 150 according to the fourth embodiment, as shown in FIG. 12, differs from the first embodiment only in a proximal side opening 160 and a locking portion 170 .

The locking portion 170 has a tapered fitting convex portion 171 whose outer diameter decreases toward the proximal side on the outer peripheral surface on the proximal side. The proximal opening 160 has a fitting recess 161 on its distal inner peripheral surface, the inner diameter of which tapers down toward the proximal side. The fitting protrusion 171 fits into the fitting recess 161 by entering the fitting recess 161 from the distal side. When the shaft portion 30 is strongly pushed distally while the fitting protrusion 171 is fitted in the fitting recess 161 , the fitting protrusion 171 is disengaged from the fitting recess 161 to the distal side. Either one of the fitting convex portion 171 and the fitting concave portion 161 is preferably made of a flexible material such as a resin material. As a result, the flexible fitting protrusion 171 or fitting recess 161 is deformed, so that the locking portion 170 can be properly fitted into the fitting recess 161 . At least one of the fitting protrusion 171 and the fitting recess 161 may not be tapered as long as the fitting protrusion 171 can be fitted into the fitting recess 161 .

Until the filter device 150 is placed in the blood vessel, the locking portion 170 can be fitted and connected to the proximal opening 160 . As a result, when the filter device 150 is transported, the filter 20 and the shaft portion 30 are not separated, and the operation is easy. The fitting force can then be used to push the shaft portion 30 distally with respect to the sheath 70 to push the filter 20 out of the sheath 70 . After the filter device 150 is placed in the blood vessel, the shaft portion 30 is pushed distally to disengage the locking portion 170 from the proximal side opening 160 . In this state, the sheath 70 and crushing device 80 are carried along the wire 31 . At this time, locking portion 170 can pass through the lumen of distal opening 50 . Therefore, it is possible to prevent the distal opening 50 from moving due to force from the locking portion 170 . Therefore, the filter 20 placed in the blood vessel can be maintained in an appropriate state.

Also, when the thrombus 200 collected by the filter 20 is to be aspirated with another medical device such as the sheath 70 , the locking portion 170 is fitted into the proximal side opening 160 . Then, the wire 31 is operated at hand to reciprocate the shaft portion 30 in the axial direction. This allows the filter 20 (especially the inner portion 44 containing the thrombus 200) in proximity to the proximal opening 160 connected to the locking portion 170 to rock. As a result, an object such as a thrombus 200 adhering to the filter 20 can be floated from the filter 20 and easily removed by suction from the engaging portion 170 .

The form of the engaging portion and the proximal opening is not particularly limited as long as they can be detachably connected. For example, as in the modification shown in FIG. 13, the locking portion 110 of the filter device 180 has an axially extending outer guiding portion 111, like the locking portion 110 in the second embodiment. The proximal opening 190 includes a movement restricting portion 191 , an accommodating portion 193 communicating with the movement restricting portion 191 , and a through hole 194 communicating with the accommodating portion 193 . The movement restricting part 191 is located at the distal part of the proximal opening 190 . The movement restricting portion 191 has a groove portion 192 extending in the axial direction. The accommodating portion 193 is located on the proximal side of the movement restricting portion 191 . The accommodating portion 193 rotatably accommodates the locking portion 110 . The through hole 194 is located on the proximal side of the housing portion 193 . The through hole 194 has an inner diameter larger than the outer diameter of the wire 31 . Furthermore, the through hole 194 has an inner diameter that cannot pass through the engaging portion 11 in the axial direction.

If the circumferential position of the outer guide portion 111 of the locking portion 110 does not match the circumferential position of the groove portion 192 of the movement restricting portion 191, the locking portion 110 moves through the inner cavity of the movement restricting portion 191 in the axial direction. Impassable. Only when the circumferential position of the outer guide portion 111 of the locking portion 110 coincides with the circumferential position of the groove portion 192 of the movement restricting portion 191 , the locking portion 110 is aligned with the inner cavity of the movement restricting portion 191 as an axis. direction can pass. Therefore, for example, the locking portion 110 is arranged in the housing portion 193 so that the circumferential position of the outer guide portion 111 does not coincide with the circumferential position of the groove portion 192 . As a result, the engaging portion 110 cannot pass through the movement restricting portion 191 and is held in the accommodating portion 193 . As a result, the locking portion 110 is connected to the proximal opening 190 . Next, the wire 31 is manually operated and rotated. As a result, the circumferential position of the outer guiding portion 111 is aligned with the circumferential position of the groove portion 192 . This allows the outer guiding portion 111 to pass through the groove portion 192 . Therefore, the locking portion 110 can pass through the movement restricting portion 191 to the distal side. Therefore, by manually adjusting the rotational position of the shaft portion 30 relative to the filter 20 , the locking portion 110 can be connected to and disconnected from the proximal opening 190 .

The present invention is not limited to the above-described embodiments, and various modifications can be made by those skilled in the art within the technical concept of the present invention. For example, the biological lumen into which the filter device is inserted is not limited to blood vessels, and may be, for example, vessels, ureters, bile ducts, fallopian tubes, hepatic ducts, and the like.

Also, the opening through which the locking portion can pass may be the proximal opening 60 instead of the distal opening 50 as in another modification shown in FIG. This allows the locking portion 32 of the shaft portion 30 to push the filter 20 distally. Therefore, the shaft portion 30 facilitates pushing out the filter 20 from the sheath 70 or the like.

At least one of the distal side opening and the proximal side opening may be configured by part of the mesh filamentous body. Also, the distal opening or the proximal opening may widen in the radial direction in the natural state.

In the above-described embodiments, the locking portion that can pass through the distal opening and/or the proximal opening can pass from both the distal side and the proximal side. However, the locking portion may be passable only from one side, distal or proximal, and not passable from the other side.

In addition, the extended portion does not have to be in a folded state in the natural state. Moreover, the medical device to be moved along the wire is not limited to a crushing device for crushing thrombus or a device for aspirating thrombus. A flexible membrane may also be secured to a portion of the filter to restrict blood flow.

10, 90, 120, 150, 180 filter device 20 filter 30 shaft portion 31 wire 32, 110, 170 locking portion 40, 140 extension portion 50, 100, 130 distal opening 60, 160, 190 proximal opening Part 70 Sheath (medical device)
80 crushing device (medical device)
101 inner guide part 111 outer guide part 200 thrombus (object)

Claims (6)

A filter device for collecting matter within a biological lumen, comprising:
a shaft portion comprising an elongated wire and a locking portion secured to a distal portion of the wire;
an expandable filter comprising a distal opening and a proximal opening;
the wire is passable through the distal opening and the proximal opening;
the locking portion is positionable between the distal opening and the proximal opening and can pass through either one of the distal opening and the proximal opening;
the proximal opening and the locking portion are connectable;
The portion connected to the proximal opening of the filter is formed in a net shape so as to be able to collect the object ,
At least one of the distal opening and the proximal opening can be flared radially outward to increase an inner diameter . A filter device for collecting matter within a biological lumen, comprising:
a shaft portion comprising an elongated wire and a locking portion secured to a distal portion of the wire;
an expandable filter comprising a distal opening and a proximal opening;
the wire is passable through the distal opening and the proximal opening;
the locking portion is positionable between the distal opening and the proximal opening and can pass through either one of the distal opening and the proximal opening;
the proximal opening and the locking portion are connectable;
The portion connected to the proximal opening of the filter is formed in a net shape so as to be able to collect the object,
at least one of the distal side opening and the proximal side opening has an inner guide portion, which is a concave portion or convex portion extending in the axial direction, on an inner peripheral surface;
The locking portion has an outer guide portion, which is a convex portion or concave portion extending in the axial direction, on the outer peripheral surface,
The outer guide is axially passable through at least one of the distal opening and the proximal opening along the inner guide . 3. The filter device of claim 1 or 2 , wherein the locking portion is axially passable through the distal opening. The filter device according to any one of claims 1 to 3 , wherein the inner diameter of at least one of the distal opening and the proximal opening is larger than the outer diameter of the locking portion. The filter has, in a natural state, a concave outer portion that opens proximally and a concave inner portion that opens proximally on the inner surface side of the outer portion,
The filter device according to any one of claims 1 to 4 , wherein the inner portion is formed in a net shape so as to be able to collect the object. 6. The method of claims 1 to 5 , wherein the proximal opening and the locking portion are connectable to limit axial movement of the wire and rotational movement about the axis of the wire. A filter device according to any one of the preceding claims.

Images