JP2024167451A - Medical Devices and Delivery Systems - Google Patents

Abstract

To provide a medical appliance that allows an operator to easily determine when a tip of an embolus is pushed out of a tip of a catheter.SOLUTION: A medical appliance is a delivery pusher 40 which is inserted into a delivery catheter assembly having an embolus-loaded catheter 20M that can be loaded with an embolus 10 and a delivery catheter 30, and pushes the embolus 10 into an organism via the delivery catheter, with a long pusher body 41 and a handle 42 provided. The pusher body includes a sensing part 44 configured to allow an operator to sense the timing when a tip of the embolus is pushed out of a tip of the catheter. The sensing part is configured to allow the embolus-loaded catheter to pass through a hemostatic valve, and has a sliding resistance change structure on an outer peripheral surface of the pusher body, the sliding resistance change structure changing the sliding resistance against the hemostatic valve when the operator inserts the delivery pusher into the catheter and advances it.SELECTED DRAWING: Figure 1

Description

The present invention relates to medical devices and delivery systems.

There is no medical treatment for aneurysms (aortic aneurysms) that develop in a patient's aorta to prevent the aneurysm from growing larger or rupturing, and surgical treatment (operation) is generally performed for aneurysms large enough to rupture. In addition, surgery for aortic aneurysms has traditionally been dominated by artificial vascular replacement surgery, in which an artificial blood vessel is implanted via laparotomy or thoracic opening, but in recent years, the use of the less invasive stent graft insertion procedure (Endovascular Aneurysm Repair; EVAR) has been rapidly expanding.

As an example, in stent graft insertion surgery for abdominal aortic aneurysm (AAA), a catheter with a stent graft at its tip is inserted through the patient's peripheral blood vessels, and the stent graft is deployed and placed at the site of the aneurysm, blocking blood flow to the aneurysm and preventing the aneurysm from rupturing.

Generally, stent grafts used in stent graft insertion have a structure that can be assembled from two types of components: a "main body" with a branching section that branches into an approximately Y shape, and "legs" that are attached to the branching section and are attached to the right iliac artery and left iliac artery, respectively.

Therefore, during stent graft insertion surgery, blood may leak from around the stent graft due to insufficient adhesion of the inserted stent graft, or blood may flow back from small blood vessels (branch vessels) that branch off from the aneurysm, resulting in a so-called "end leak," in which blood remains flowing inside the aneurysm. In this case, the blood flow that has entered the aneurysm puts pressure on the aneurysm wall, creating a potential risk of the aneurysm rupturing.

The following Patent Document 1 discloses a device that includes a catheter capable of holding a compressed, relatively elongated sponge (embolus) in its lumen, and a plunger that pushes the embolus held in the catheter into the blood-filled aneurysm, in order to block the remaining blood flow into an aortic aneurysm caused by an end leak. The sponge used in this device expands immediately when exposed to blood, so when it is pushed into the aneurysm and absorbs the blood inside the aneurysm, it expands (swells), and is left in that state inside the aneurysm to block the blood flow and prevent rupture.

U.S. Pat. No. 9,561,096

The plunger disclosed in Patent Document 1 can push the embolus held in the catheter into the aneurysm by being inserted from the base end side of the catheter. When the embolus is pushed out from the tip of the catheter and comes into contact with the inside of the aneurysm (lesion), it immediately expands. In addition, there is a risk that the embolus pushed into the aneurysm may come into contact with the blood vessel wall and damage the lesion. Therefore, the surgeon needs to closely watch the timing when the tip of the embolus is pushed out from the tip of the catheter through the angiogram. However, if the contrast of the embolus is weak, if the contrast of the embolus is similar to that of the pusher, or if a highly contrast-rich member is placed near the lesion, it may be difficult for the surgeon to judge the timing when the embolus is pushed out from the tip of the catheter through the angiogram.

At least one embodiment of the present invention has been made in consideration of the above problems, and aims to provide a medical device and delivery system that can easily determine the timing at which the tip of an embolus loaded in a catheter will be pushed out from the tip of the catheter.

The medical device according to this embodiment is a delivery pusher that is inserted into a delivery catheter assembly including an embolus-loaded catheter configured to be loaded with an embolus to be inserted and placed in a living body, and a delivery catheter that is connected to the embolus-loaded catheter while placed in a living body lumen, and that pushes the embolus loaded in the embolus-loaded catheter into the living body via the delivery catheter. The medical device includes an elongated pusher body that can be inserted into a delivery lumen defined by the delivery catheter assembly and has an outer circumferential surface facing the delivery lumen, and a handle portion that extends from the base end of the pusher body and has an outer circumferential surface that is gripped by the surgeon when delivering the embolus into the living body, and the pusher body includes a first insertion portion that extends from the tip of the pusher body and can be inserted into the delivery lumen, and a handle portion that is disposed at the base end of the first insertion portion and allows the surgeon to sense the timing when the tip of the embolus is pushed out from the tip of the delivery lumen into the living body. and a second insertion part extending from the base end of the sensing part toward the base end of the pusher body and configured to push the base end of the embolus from the tip of the delivery lumen into the living body by being inserted into the delivery lumen. The sensing part is configured to be able to pass through a hemostatic valve provided at the base end of the embolus-loaded catheter, and has a sliding resistance changing structure on the outer circumferential surface of the pusher body that changes the sliding resistance against the hemostatic valve when the surgeon inserts the delivery pusher into the delivery catheter assembly and advances it.

In addition, the medical device according to one embodiment of the present invention is a delivery pusher that connects an embolus-loaded catheter configured to be capable of being loaded with an embolus to be inserted and placed in a living body to a delivery catheter placed in a living body lumen, moves the embolus loaded in the loading lumen of the embolus-loaded catheter to the delivery lumen of the delivery catheter, and then inserts into the delivery catheter in a state in which the embolus-loaded catheter has been removed, to push out the embolus stored in the delivery catheter into the living body. The medical instrument includes a long pusher body that can be inserted into the delivery lumen of the delivery catheter and has an outer circumferential surface facing the delivery lumen, and a handle portion that extends from a base end of the pusher body and has an outer circumferential surface that is gripped by an operator when delivering the embolus into a living body, and the pusher body includes a first insertion portion that extends from a tip of the pusher body and can be inserted into the delivery lumen of the delivery catheter, and a handle portion that is disposed at the base end of the insertion portion and allows the operator to sense the timing at which the tip of the embolus is pushed out from the tip of the delivery lumen into the living body. and a second insertion part extending from the base end of the sensing part to the base end of the pusher body and configured to push the base end of the embolus from the tip of the delivery lumen into the living body by being inserted into the delivery lumen. The sensing part is configured to be able to pass through a hemostatic valve provided at the base end of the catheter loaded with the embolus, and has a sliding resistance changing structure on the outer circumferential surface of the pusher body that changes the sliding resistance against the hemostatic valve when the surgeon inserts the delivery pusher into the delivery catheter and advances it.

The delivery system according to this embodiment also includes the delivery pusher described above, a loading catheter configured to be capable of loading the embolus, and a delivery catheter to which the loading catheter is attached and detached.

According to at least one embodiment of the present invention, the sliding resistance of the delivery pusher against the hemostatic valve of the catheter changes when the tip of the embolus is pushed out from the tip of the catheter. This allows the surgeon to easily determine the timing when the embolus is pushed out from the tip of the catheter.

1A to 1C are diagrams showing the configuration of a delivery system including a delivery pusher according to a first embodiment of the present invention and a delivery catheter assembly into which the delivery pusher can be inserted. 1 is a diagram showing a configuration of an embolus delivery medical system according to a first embodiment of the present invention. 1A to 1C are diagrams showing a configuration of a delivery catheter assembly according to a first embodiment of the present invention. 2 is a diagram showing a sensing unit according to the first embodiment of the present invention; FIG. FIG. 13 is a partially enlarged view showing the insertion state of the delivery pusher. FIG. 5B is a partially enlarged view of FIG. 5A and is a partial cross-sectional view along the axial direction. FIG. 13 is a diagram showing a modified example of the sensing unit. FIG. 13 is a diagram showing a modified example of the sensing unit. FIG. 13 is a diagram showing a modified example of the sensing unit. FIG. 2 is a diagram showing a recognition unit according to the first embodiment of the present invention. FIG. 13 is a diagram showing a modified example of the recognition unit. FIG. 13 is a diagram showing a modified example of the recognition unit. FIG. 13 is a diagram showing a modified example of the recognition unit. FIG. 13 is a diagram showing an example of the operation of an embolic material delivery medical system according to one embodiment of the present invention, illustrating a state in which a delivery catheter has been delivered into a lump (inside a living body). FIG. 13 is a diagram showing an example of operation of the embolus delivery medical system according to one embodiment of the present invention, illustrating a state in which a stent graft is deployed within a lump (inside a living body). FIG. 2 is a diagram showing an example of the operation of an embolic material delivery medical system according to one embodiment of the present invention, illustrating a state before an embolic material-loaded catheter is attached to a delivery catheter. FIG. 13 is a diagram showing an example of the operation of an embolic material delivery medical system according to one embodiment of the present invention, illustrating a state in which a catheter loaded with an embolic material is attached to a delivery catheter. 1A and 1B are diagrams illustrating an example of the operation of an embolic material delivery medical system according to one embodiment of the present invention, showing a state in which a delivery pusher is being inserted into an embolic material-loaded catheter. FIG. 13 is a diagram showing an example of operation of the embolic material delivery medical system according to one embodiment of the present invention, illustrating a state in which the embolic material has been pushed out into the aneurysm (inside the living body) by the delivery pusher. FIG. 13 is a diagram showing an example of the operation of an embolic material delivery medical system according to one embodiment of the present invention, illustrating a state in which an embolic material-loaded catheter is detached from a delivery catheter. 13A to 13C are diagrams showing the configuration of a delivery pusher and a delivery catheter assembly according to a modified example of the first embodiment of the present invention. 11A and 11B are diagrams showing the configurations of a delivery pusher and a delivery catheter according to a second embodiment of the present invention. FIG. 11 is a diagram showing an example of operation of the embolus delivery medical system according to the second embodiment of the present invention, illustrating a state in which a delivery pusher is being inserted into a delivery catheter.

The following describes in detail the embodiments of the present invention with reference to the drawings. The embodiments shown here are merely illustrative in order to embody the technical ideas of the present invention, and do not limit the present invention. Furthermore, all other possible embodiments, examples, and operational techniques that can be conceived by those skilled in the art without departing from the gist of the present invention are included in the scope and gist of the present invention, and are included in the scope of the inventions described in the claims and their equivalents.

In addition, the drawings attached to this specification may be depicted diagrammatically and with appropriate changes in scale, aspect ratio, shape, etc. from the actual product for the convenience of illustration and ease of understanding, but these are merely examples and do not limit the interpretation of the present invention.

In addition, in this specification, the operation direction of each part constituting the embolus delivery medical system 300 capable of delivering the embolus 10 into the aneurysm (inside the living body) is, for example, a direction along the axial direction of the delivery catheter 30 for delivering the embolus-loaded catheter 20M into the aneurysm (inside the living body), and the side where the embolus 10 is transported into the aneurysm (inside the living body) is referred to as the "distal side (or distal end)", and the side located axially opposite the distal side and operated by the surgeon (the side where the delivery catheter 30 is removed) is referred to as the "proximal side (or proximal end)". Note that "distal" refers to a certain range in the axial direction including the most distal end, and "proximal" refers to a certain range in the axial direction including the most proximal end.

In the following explanation, when ordinal numbers such as "first" and "second" are used, they are used for convenience and do not dictate any particular order, unless otherwise specified.

[composition]
A delivery pusher 40 (corresponding to a "medical instrument") according to this embodiment, a delivery system 200 using the delivery pusher 40, and an embolus delivery medical system 300 will be described.

The delivery system 200 and embolic material delivery medical system 300 according to this embodiment can be applied to, for example, endoleak embolization for stent graft insertion of abdominal aortic aneurysm (AAA), which is a treatment method for preventing the rupture of aneurysms (e.g., aneurysms) occurring in blood vessels. In addition, the treatment methods to which the delivery catheter assembly 100, delivery system 200, and embolic material delivery medical system 300 according to this embodiment can be applied are not limited to the above-mentioned endoleak embolization, but can also be applied to other interventional treatment methods for preventing the rupture of aneurysms occurring in blood vessels.

The delivery system 200 and the embolus delivery medical system 300 according to this embodiment can also be applied to vascular embolization, which embolizes the blood vessel itself. Examples of vascular embolization include (1) placing an embolizer in the blood vessel before or after an aneurysm to block blood flow to an iliac artery aneurysm or visceral artery aneurysm (renal artery aneurysm, splenic artery aneurysm, hepatic artery aneurysm, etc.), (2) placing an embolizer in a blood vessel to block blood flow to an arteriovenous malformation or arteriovenous fistula, (3) placing an embolizer in the subclavian artery to suppress type II endoleak in stent graft insertion for a thoracic aortic aneurysm, (4) placing an embolizer in a vein to stop blood backflow in pelvic congestion syndrome, (5) placing an embolizer in a blood vessel before a varicose vein to stop blood flow into the varicose vein in a varicocele, and (6) placing an embolizer in a blood vessel just before the varicose vein to block blood flow to a cancer lesion.

Figure 1 shows the configuration of a delivery system 200 including a delivery pusher 40 according to a first embodiment of the present invention, and a delivery catheter assembly 100 into which the delivery pusher 40 can be inserted, including an embolic material-loaded catheter 20M and a delivery catheter 30. Figure 2 shows the configuration of an embolic material delivery medical system 300, and Figure 3 shows the configuration of the delivery catheter assembly 100. Figures 4 to 8C show the configuration of the delivery pusher 40. Note that Figures 1, 2, and 5A show a simplified view of the delivery pusher 40, and Figure 5B shows only the catheter 20 in cross section.

The arrow X in the drawing indicates the "axial direction (longitudinal direction)" of the catheter body 21 of the embolus-loaded catheter 20M into which the delivery pusher 40 is inserted, the arrow Y indicates the "width direction (depth direction)" of the catheter body 21, and the arrow Z indicates the "height direction" of the catheter body 21.

Delivery Pusher
As shown in Figures 1 to 3, the delivery pusher 40 is a rod-shaped member that can be inserted into a delivery catheter assembly 100 (described later) that is composed of an embolus-loaded catheter 20M and a delivery catheter 30 attached to the tip of the embolus-loaded catheter 20M.

When the delivery pusher 40 is inserted from the base end hub 23 side of the embolus-loaded catheter 20M with the embolus-loaded catheter 20M attached to the delivery catheter 30 and pushed out along the axial direction of the delivery catheter assembly 100, the embolus 10 loaded in the embolus-loaded catheter 20M can be pushed out to the outside (inside the aneurysm (inside the living body)) through the sheath lumen 32 of the delivery catheter 30.

As shown in Figures 1 and 5A, the delivery pusher 40 includes a rod-shaped pusher body 41 and a handle portion 42 that is provided at the base end of the pusher body 41 and is held by the surgeon when delivering the embolus 10 into the aneurysm (inside the living body).

The pusher body 41 is configured to be insertable into the delivery lumen (lumen extending from the base end of the loading lumen 22 of the embolus-loaded catheter 20M to the tip of the sheath lumen 32 of the delivery catheter 30) defined by the delivery catheter assembly 100 shown in FIG. 3, and has an outer circumferential surface 41C (see FIG. 4) that faces the delivery lumen.

As shown in FIG. 1, the pusher body 41 includes a first insertion portion 43 extending from the tip 41a of the pusher body 41, a sensing portion 44 disposed at the base end of the first insertion portion 43, and a second insertion portion 45 extending from the base end of the sensing portion 44 toward the base end 41b of the pusher body 41.

The first insertion section 43, the sensing section 44, and the second insertion section 45 are configured to be able to pass through the hemostatic valve 27 (see FIG. 5B) provided at the base end of the embolus-loaded catheter 20M (catheter 20), but the sensing section 44 has a sliding resistance change structure that changes the sliding resistance against the hemostatic valve 27 when the surgeon inserts the delivery pusher 40 into the delivery catheter assembly 100 and advances it forward.

As shown in FIG. 4, the sliding resistance change structure of the sensing unit 44 is composed of a plurality of recesses 44k (corresponding to "first recesses") provided in the pusher body 41, and each of the recesses 44k is provided in the outer peripheral surface 41C of the pusher body 41 and recessed from the outer peripheral surface 41C.

Each of the recesses 44k is provided along the circumferential direction of the pusher body 41 to form a sliding resistance change structure. The sliding resistance change structure 44A is disposed at a preset position between a first position L1 (see FIG. 1) that is a distance from the base end 41b of the pusher body 41 toward the tip 41a of the pusher body 41 by the length X1 of the embolus 10 (the length of the embolus 10 when placed in the loading lumen 22 of the catheter 20, which is a part of the delivery lumen, or the sheath lumen 32 of the delivery catheter 30), and a second position L2 (see FIG. 1) that is a predetermined distance from the first position L1 toward the tip 41a of the pusher body 41.

As shown in FIG. 4, the sensing unit 44 is configured with a plurality of sliding resistance change structures 44A-44D, each of which is provided along the axial direction of the pusher body 41. Each of the sliding resistance change structures 44A-44D is provided toward the base end 41b of the pusher body 41, with the sliding resistance change structure 44A, which is located between the first position L1 and the second position L2, as a reference.

The body length X3 (see FIG. 1) of the pusher body 41 is longer than the length X2 from the base end of the insertion passage 23a of the base end hub 23 to the tip opening 31a (the tip opening communicating with the sheath lumen 32) of the sheath 31 of the delivery catheter 30 in the attached state (see FIG. 3) in which the delivery catheter 30 is attached to the tip of the embolus-loaded catheter 20M. Therefore, if the delivery pusher 40 is inserted from the base end hub 23 in the state in which the embolus-loaded catheter 20M and the delivery catheter 30 are attached, the embolus 10 loaded in the loading lumen 22 can be pushed out into the aneurysm (inside the living body) by passing through the tip connection part 28 → the sheath hub 33 → the sheath lumen 32 in that order with a single pushing operation. The body length X3 of the pusher body 41 is not particularly limited, but is preferably about 0.2 to 20 mm longer than the length X2.

With this configuration, when the surgeon inserts the distal end of the first insertion portion 43 into the delivery lumen and advances the delivery pusher 40 until the base end of the first insertion portion 43 is located proximal to the hemostasis valve 27 of the catheter 20, the distal end of the embolus 10 can be protruded from the distal end opening of the delivery catheter assembly 100 (the distal end opening 31a of the delivery catheter 30). When the sliding resistance change structure 44A constituting the sensing unit 44 passes through the hemostasis valve 27 of the catheter 20 (see Figures 5A and 5B), the sliding resistance of the delivery pusher 40 against the hemostasis valve 27 changes. The sliding resistance of the delivery pusher 40 against the hemostasis valve 27 continues to occur until the sliding resistance change structure portions 44A to 44D pass through the hemostasis valve 27. Therefore, the surgeon can easily determine the timing at which the embolus 10 is pushed out from the distal end of the delivery catheter 30. In addition, when the surgeon advances the delivery pusher 40 until the base end of the second insertion section 45 passes through the hemostatic valve 27, the pusher body 41 can protrude the entire embolus 10 from the tip opening 31a of the delivery catheter 30.

The configuration of the sensing unit 44 can be changed as appropriate, as described below.

For example, the shape of the sensing portion 44 is not particularly limited. As in the sensing portion 44P of the delivery pusher 40P shown in FIG. 6A, the pusher body 41P may have a plurality of protrusions 44l (corresponding to "first protrusions") protruding from the outer circumferential surface of the pusher body 41P as a sliding resistance changing structure. By configuring the pusher body 41P in this manner, when the surgeon passes the sensing portion 44P through the hemostasis valve 27, the sliding resistance of the delivery pusher 40P against the hemostasis valve 27 changes (the sliding resistance increases), allowing the surgeon to sense the timing when the tip of the embolus 10 is pushed out from the tip of the delivery lumen (the tip opening 31a of the delivery catheter 30) into the aneurysm (inside the living body).

The protrusion constituting the sensing part may also be tapered. As shown in FIG. 6B, the protrusion 44m constituting the sensing part 44Q of the delivery pusher 40Q may be configured so that the protruding length X4 from the outer circumferential surface of the pusher body 41Q gradually increases from the base end 44mb of the protrusion 44m to the tip 44ma of the protrusion 44m. By configuring in this manner, the sensing part 44Q can suppress the amount of change in the sliding resistance against the hemostasis valve 27 that occurs when the operator retracts the delivery pusher 40Q, while ensuring the amount of change in the sliding resistance against the hemostasis valve 27 that occurs when the operator advances the delivery pusher 40Q. Therefore, the operator can sense the timing when the tip of the embolus 10 is pushed out from the tip of the delivery lumen into the aneurysm (inside the living body) by the delivery pusher 40Q, and can easily pull out the delivery pusher 40Q from the delivery catheter assembly 100.

As shown in FIG. 6C, the sensing part 44R of the delivery pusher 40R may have a high sliding resistance structure having a higher sliding resistance against the hemostasis valve 27 than the insertion part (first insertion part 43R or second insertion part 45R) as a sliding resistance change structure. The high sliding resistance structure can allow the surgeon to recognize the difference in sliding performance of the delivery pusher 40R by the presence or absence of a lubricating coating or silicone coating applied to the outer circumferential surface of the pusher body 41 of the delivery pusher 40R, or the difference in sliding performance. The high sliding resistance structure may also be provided in the second insertion part 45R. By configuring in this way, the surgeon who senses the change in sliding resistance by the sensing part 44R can carefully (slowly) push the embolus 10 from the delivery lumen into the aneurysm (inside the living body) when continuing to push the delivery pusher 40R.

The sensing unit may also be a structure that combines the various sliding resistance change structures described above. For example, the sensing unit of the delivery pusher may have a sliding resistance change structure formed by embossing the outer circumferential surface of the pusher body.

The material of the pusher body 41 is not particularly limited as long as it has the appropriate hardness and flexibility to transport the embolus 10. Examples of suitable materials for the pusher body 41 include polyolefins (e.g., polyethylene, polypropylene, polybutene, ethylene-propylene copolymers, ethylene-vinyl acetate copolymers, ionomers, or mixtures of two or more of these), polyolefin elastomers, crosslinked polyolefins, polyvinyl chloride, polyamides, polyamide elastomers, polyesters, polyester elastomers, polyurethanes, polyurethane elastomers, fluororesins such as ETFE, polymeric materials such as polycarbonates, polystyrenes, polyacetals, polyimides, polyetherimides, and aromatic polyether ketones, or mixtures of these polymeric materials, and metal materials such as shape memory alloys, stainless steels, tantalum, titanium, platinum, gold, and tungsten.

As shown in Figures 1 and 7, the handle portion 42 has a recognition portion 46 provided adjacent to the base end of the second insertion portion 45.

As shown in FIG. 7, the recognition section 46 has an extremely high sliding resistance structure in which the sliding resistance against the hemostasis valve 27 increases significantly when the surgeon inserts the delivery pusher 40 into the delivery catheter assembly 100 and advances it forward, and the extremely high sliding resistance structure of the recognition section 46 is constituted by an inclined section 46k (corresponding to a "second recess") provided in the handle section 42. The inclined section 46k is provided on the outer peripheral surface 42C of the handle section 42, recessed from the outer peripheral surface 42C, and has a tapered shape configured such that its outer diameter gradually increases from the base end of the second insertion section 45.

By configuring the handle portion 42 in this manner, when the surgeon inserts the tip side of the first insertion portion 43 into the delivery lumen and advances the delivery pusher 40 until the tip of the recognition portion 46 passes through the hemostatic valve 27, the sliding resistance of the delivery pusher 40 against the hemostatic valve 27 changes suddenly (the sliding resistance becomes very high), allowing the surgeon to easily recognize that the tip 41a of the pusher body 41 is approaching the tip of the delivery lumen. In addition, the surgeon can push the tapered recognition portion 46 into the hemostatic valve 27 as necessary, and can fine-tune the position of the embolus 10 by pushing the embolus 10 inside the aneurysm (inside the living body) with the tip of the delivery pusher 40.

The configuration of the recognition unit 46 can be appropriately changed as described below.
There are.

For example, the recognition portion 46 may be configured to be able to pass through the hemostasis valve 27. As in the recognition portion 46S of the delivery pusher 40S shown in FIG. 8A, the recognition portion 46S may have a plurality of protrusions 46l (corresponding to the "second protrusions") provided to protrude from the outer circumferential surface of the handle portion 42S as an extremely high sliding resistance structure. The protrusions 46l have a tapered shape configured such that the protrusion length from the outer circumferential surface of the handle portion 42S gradually increases from the base end of the protrusions 46l to the tip end of the protrusions 46l. Each of the protrusions 46l is provided along the circumferential direction of the handle portion 42S to form an extremely high sliding resistance structure portion, and the extremely high sliding resistance structure portions are provided along the axial direction of the handle portion 42S to form a plurality of extremely high sliding resistance structure portions 46A to 46C. The handle portion 42S is configured so that when the surgeon inserts the distal end side of the first insertion portion 43 into the delivery lumen and advances the delivery pusher 40S until the base end of the recognition portion 46 passes through the hemostasis valve 27, the distal end of the pusher body reaches the distal end of the delivery lumen. Therefore, each of the multiple extremely high sliding resistance structural portions 46A to 46C is provided toward the distal end of the handle portion 42S with the extremely high sliding resistance structural portion 46C as a reference. By configuring the handle portion 42S in this manner, the sliding resistance of the delivery pusher 40S against the hemostasis valve 27 changes suddenly (the sliding resistance increases suddenly) every time the surgeon passes the convex portion 461 through the hemostasis valve 27. Even if the surgeon is unable to recognize the timing when the distal end of the pusher body 41S reaches the distal end of the delivery lumen with the first extremely high sliding resistance structural portion 46A, the remaining extremely high sliding resistance structural portions 46B and 46C can make the surgeon recognize the timing.

8B, the pusher body 41T may be configured to be unable to pass through the hemostasis valve 27 of the catheter 20 into which it is inserted, and may have a protrusion 46m (corresponding to the "third protrusion") provided to protrude from the outer circumferential surface of the handle portion 42T. The handle portion 42T has a large-diameter umbrella portion 42Ta constituting the recognition portion 46T at the tip side, and a small-diameter handle portion 42Tb extending to the base end side of the large-diameter umbrella portion 42Ta, and has a generally mushroom-shaped shape. The outer diameter of the large-diameter umbrella portion 42Ta, which is the maximum outer diameter of the handle portion 42T, is designed to be larger than the inner diameter of the insertion passage 23a of the base end hub 23. As a result, when the delivery pusher 40T is inserted into the catheter 20, the large-diameter umbrella portion 42Ta is not inserted into the insertion passage 23a of the base end hub 23, so that the insertion length of the delivery pusher 40 can be limited. In addition, because the large-diameter umbrella portion 42Ta prevents the handle portion 42T from entering the base-end hub 23, when the delivery pusher 40T has finished pushing out the embolus 10, the catheter 20M loaded with the embolus can be easily removed while still inserted, simplifying the removal operation.

In addition, like the recognition portion 46U of the delivery pusher 40U shown in FIG. 8C, the pusher body 41U may have a marker portion 46n of a different color from the second insertion portion 45U. By visually checking the marker portion 46n, the surgeon can easily recognize that the tip of the pusher body 41U is approaching the tip of the delivery lumen.

The recognition unit may also be a combination of the various extremely high sliding resistance structures and marker units described above.

The recognition unit may also be configured with an extremely high sliding resistance structure formed by a non-slip treatment such as polyurethane coating. The extremely high sliding resistance structure of the recognition unit may be configured to have a higher sliding resistance against the hemostasis valve 27 than the high sliding resistance structure of the sensing unit, and the sudden change in the sliding resistance of the delivery pusher against the hemostasis valve 27 (sudden increase in sliding resistance) allows the surgeon to recognize the timing when the tip of the pusher body reaches the tip of the delivery lumen. The extremely high sliding resistance structure formed by a non-slip treatment may be provided on the entire handle unit, allowing the surgeon to more securely grip the handle unit with his or her hand. In this case, the recognition unit is configured from the tip of the high sliding resistance structure.

Delivery Catheter Assembly
As shown in FIG. 3, the delivery catheter assembly 100 includes an embolus-loaded catheter 20M loaded with an embolus 10, and a delivery catheter 30 that is connected to the embolus-loaded catheter 20M while being placed in a biological lumen.

(embolus)
The embolus 10 is placed in a stenosis, such as an aneurysm, that occurs in a blood vessel, and expands by absorbing liquid, including blood, that flows into the stenosis. The embolus 10 is loaded into a catheter 20 (corresponding to a "loading catheter"), and in a state in which the catheter 20M loaded with the embolus is attached to a delivery catheter 30, the embolus 10 is pushed out by a delivery pusher 40 and placed in the stenosis.

The embolus 10 is a long, thin, fibrous filament (linear body) made of an expandable material (such as a polymeric material (water-absorbing gel material)) that expands upon contact with aqueous liquids, including blood, under physiological conditions.

Here, "physiological conditions" refers to conditions having at least one environmental characteristic within or on the surface of a mammal (e.g., human). Such characteristics include an isotonic environment, a pH buffer environment, an aqueous environment, a pH near neutral (about 7), or a combination thereof. In addition, "aqueous liquid" includes, for example, isotonic liquid, water; and mammalian (e.g., human) body fluids such as blood, cerebrospinal fluid, plasma, serum, vitreous humor, and urine. The outer diameter of the embolus 10 may be accommodated within the inner diameter of the embolus-loaded catheter 20M and the delivery catheter 30, and may be, for example, approximately equal to the inner diameter of these catheters. In addition, the total length of the embolus 10 is not particularly limited, but may be appropriately determined depending on the size of the aneurysm to be placed, taking into consideration the ease of loading and the shortening of the procedure time.

The material of the embolus 10 is not particularly limited, so long as it expands by absorbing at least a liquid such as blood, and is not (or is extremely low in) harmful to the human body when placed in the aneurysm (inside the living body). The embolus 10 may also contain a visualization material that allows the location of the embolus 10 within the aneurysm (inside the living body) to be confirmed by a method such as X-rays, fluorescent X-rays, ultrasound, fluorescence, infrared rays, or ultraviolet rays.

<Embolus-loaded catheter>
As shown in FIG. 1, the embolus-loaded catheter 20M comprises a long catheter body 21, a base-end hub 23 provided on the base-end side of the catheter body 21, and a flexible tube 24 having one end connected to the base-end side of the base-end hub 23 and the other end connected to a port 26 of a stopcock 25.

The catheter body 21 is a tubular member with a hole formed therein that communicates from the tip opening to the base opening along the axial direction, and has a loading lumen 22 configured to be able to load the embolus 10, and a tip portion including a tip opening 21a that communicates with the tip of the loading lumen 22. The length of the catheter body 21 in the extension direction is determined as appropriate, but it is sufficient that the catheter body 21 is at least long enough to accommodate the embolus 10.

The inner diameter of the loading lumen 22 is designed to be approximately equal to the inner diameter of the sheath lumen 32 of the delivery catheter 30. This allows the outer diameter of the embolus 10 to be approximately equal to the inner diameters of the embolus-loaded catheter 20M and the delivery catheter 30.

The catheter 20 is generally provided with the embolus 10 already loaded, but the embolus 10 loaded into the catheter body 21 may be grasped by an operator and loaded into the catheter body 21. The embolus 10 may be loaded by an operator grasping the embolus 10 and inserting it from the tip connection part 28 side or the base hub 23 side of the catheter 20.

The material of the catheter body 21 is not particularly limited as long as it has a suitable hardness to prevent damage to the embolus 10 loaded during packaging, etc. Examples of materials that can be used for the catheter body 21 include polymeric materials such as polyolefin (e.g., polyethylene, polypropylene, polybutene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ionomer, or a mixture of two or more of these), polyether block amide copolymer, polyolefin elastomer, crosslinked polyolefin, polyvinyl chloride, polyamide, polyamide elastomer, polyester, polyester elastomer, polyurethane, polyurethane elastomer, fluorine-based resin, polycarbonate, polystyrene, polyacetal, polyimide, polyetherimide, aromatic polyether ketone, or a resin material such as a mixture of these, shape memory alloy, stainless steel, tantalum, titanium, platinum, gold, and metal materials such as tungsten.

In order to prevent damage to the embolus 10, the catheter body 21 may be made of a hard material, or when the same material as the sheath 31 is used, the catheter body 21 may be made thicker to prevent kinking. In the case of a variable thickness catheter body 21, the outer diameter of the catheter body 21 is larger than the outer diameter of the sheath 31, but this does not pose a problem because the catheter 20M loaded with the embolus is attached to the delivery catheter 30 via an engagement portion (not shown).

The base end hub 23 is an intermediate member that has an insertion passage 23a (lumen) that communicates the loading lumen 22 of the catheter body 21 with the tube 24, and allows the fluid (priming liquid such as saline) flowing in from the stopcock 25 to flow through the catheter body 21 via the tube 24. The base end hub 23 functions as an injection hub that can inject priming liquid into the loading lumen 22 of the catheter 20M loaded with an embolus. The embolus 10 loaded in the loading lumen 22 is pushed out toward the delivery catheter 30 by inserting the delivery pusher 40 into the loading lumen 22 via the insertion passage 23a of the base end hub 23.

The material of the base end hub 23 is not particularly limited as long as it is a hard material such as a hard resin. Examples of materials that can be used to form the base end hub 23 include polyolefins such as polyethylene and polypropylene, polyamides, polycarbonates, and polystyrene.

A hemostasis valve 27 is attached to the inside of the base end side of the base end hub 23. The hemostasis valve 27 may be a substantially elliptical membrane-shaped (disk-shaped) valve body made of, for example, an elastic material such as silicone rubber, latex rubber, butyl rubber, or isoprene rubber.

One end of the tube 24 is connected to the base end side of the base end hub 23, and the other end is connected to the port 26 of the stopcock 25. The tube 24 is a conduit through which liquid such as saline flows out of a priming syringe (not shown) connected to the port 26.

The tube 24 is not particularly limited as long as it is made of a resin material that is flexible and allows for ease of use. Examples of suitable materials for the tube 24 include polyolefins such as polyethylene, polypropylene, and ethylene-propylene copolymers, polyesters such as polyethylene terephthalate, polystyrene, and polyvinyl chloride.

The stopcock 25 communicates with the insertion passage 23a of the base end hub 23 and the loading lumen 22 of the catheter body 21 via the tube 24. The base end side of the tube 24 can be connected to the port 26 of the stopcock 25, and a priming syringe for priming the loading lumen 22 of the catheter body 21 can also be connected. In this embodiment, the stopcock 25 is a three-way stopcock. However, the stopcock 25 is not limited to a three-way stopcock, and other forms (such as a two-way stopcock or a multi-way stopcock with four or more ports) may also be used.

Delivery Catheter
The delivery catheter 30 may be, for example, an existing catheter that can be placed in a body lumen.

The delivery catheter 30 is provided with a sheath 31 made of a long tubular member having a hole (sheath lumen 32) that is connected from the tip opening to the base opening along the axial direction, and is placed in a living lumen to function as an introduction path for delivering the embolus 10 to the aneurysm (inside the living body). The main body 51 of the insertion assisting member 50 described below can be inserted through the entire length of the sheath 31. Therefore, the axial length of the sheath 31 is set to be at least shorter than the main body 51 of the insertion assisting member 50.

The inner diameter of the sheath lumen 32 is designed to be approximately equal to the inner diameter of the loading lumen 22. This allows the embolus 10 to be moved smoothly from the loading lumen 22 to the sheath lumen 32 when the embolus-loaded catheter 20M and the delivery catheter 30 are connected by the tip connection part 28.

The material of the sheath 31 is not particularly limited as long as it has flexibility and rigidity to a degree that allows it to follow the curved shape of the biological lumen, such as meandering or curvature. Examples of materials that can be suitably used for the sheath 31 include polymer materials such as polyolefin (e.g., polyethylene, polypropylene, polybutene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ionomer, or a mixture of two or more of these), polyolefin elastomer, crosslinked polyolefin, polyvinyl chloride, polyamide, polyamide elastomer, polyester, polyester elastomer, polyurethane, polyurethane elastomer, fluorine-based resin, polycarbonate, polystyrene, polyacetal, polyimide, polyetherimide, aromatic polyether ketone, or resin materials such as mixtures of these.

The delivery catheter 30 also includes a sheath hub 33 that is connected to the base end of the sheath 31, and a flexible tube 34 that is connected at one end to the base end of the sheath hub 33 and at the other end to a stopcock 35.

The sheath hub 33 is provided with a communication passage 33a that connects the sheath lumen 32 and the tube 34, and the loading lumen 22 and the sheath lumen 32, and is an intermediate member that allows the fluid (priming solution, etc.) flowing in from the stopcock 35 to flow through the tube 34 to the sheath 31, and also guides the embolus 10 pushed out of the embolus-loaded catheter 20M into the sheath lumen 32. The insertion assist member 50 is inserted into the sheath hub 33 when the delivery catheter 30 is placed in the biological lumen.

The constituent material of the sheath hub 33 can be the same as the materials exemplified as the constituent material of the base end hub 23 described above.

The sheath hub 33 is connected to the tip connection part 28 of the catheter 20M loaded with an embolus. When the sheath hub 33 and the tip connection part 28 are connected, the loading lumen 22 and the sheath lumen 32 are aligned in the axial direction. This prevents the embolus 10 pushed out of the catheter body 21 from colliding with the inner wall surface of the sheath hub 33 and being damaged (bending or crushing of the tip side).

One end of the tube 34 is connected to the base end side of the sheath hub 33, and the other end is connected to the port 36 of the stopcock 35. The tube 34 is a conduit through which a liquid such as physiological saline flows out of a priming syringe (not shown) connected to the port 36. The material of the tube 34 may be the same as the material exemplified as the material of the tube 24 described above.

The stopcock 35 communicates with the communication passage 33a of the sheath hub 33 and the sheath lumen 32 of the sheath 31 via the tube 34. The port 36 of the stopcock 35 can be connected to the base end side of the tube 34, as well as to a priming syringe for priming the sheath lumen 32 of the sheath 31 and a liquid injection syringe for injecting a contrast agent or a drug. In this embodiment, the stopcock 35 is a three-way stopcock. However, the stopcock 35 is not limited to a three-way stopcock, and other forms (such as a two-way stopcock or a multi-way stopcock with four or more ports) may be used.

A hemostatic valve (not shown) is attached to the inside of the base end of the sheath hub 33. The hemostatic valve may be a substantially elliptical membrane (disk-shaped) valve body made of an elastic material such as silicone rubber, latex rubber, butyl rubber, or isoprene rubber.

Here, we will explain example dimensions of each device that constitutes the delivery catheter assembly 100 according to this embodiment. Note that the values shown below are examples and are not limited to these.

In the delivery catheter assembly 100 according to this embodiment, when the delivery catheter 30 is a catheter with an outer diameter of 5 Fr (inner diameter 1.19 mm) and the procedure to be applied is endoleak embolization for stent graft insertion of abdominal aortic aneurysm (AAA), the outer diameter of the embolus 10 can be 0.4 to 1.1 mm (preferably about 1.0 mm), and the inner diameter of the embolus-loaded catheter 20M can be 1.0 to 1.5 mm (preferably about 1.2 mm) equivalent to the inner diameter of the delivery catheter 30. In addition, the body length of the catheter body 21 of the embolus-loaded catheter 20M can be 30 to 105 cm (preferably about 42 cm), the body length of the sheath 31 of the delivery catheter 30 can be 39 to 90 cm (preferably about 70 cm), and the body length of the pusher body 41 of the delivery pusher 40 can be 79 to 205 cm (preferably about 119 cm). The total length of the embolus 10 is determined appropriately depending on the size of the aneurysm, but can be in the range of 10 to 100 cm (preferably about 40 cm) from the standpoint of ease of loading into the embolus-loaded catheter 20M and shortening the procedure time.

<Delivery system>
Next, a description will be given of a delivery system 200 according to this embodiment. As shown in Fig. 1, the delivery system 200 according to this embodiment includes a delivery pusher 40 in addition to a delivery catheter assembly 100.

The delivery catheter assembly 100 and the delivery pusher 40 can be sold as a set and supplied to the market as the delivery system 200, but even if the embolus-loaded catheter 20M and the delivery pusher 40 are sold as a medical device set and supplied to the market, an existing catheter can be used as the delivery catheter 30 to function as the delivery system 200.

<Embolization delivery medical system>
Next, a description will be given of the configuration of the embolic object delivery medical system 300 according to this embodiment. As shown in Fig. 2, the embolic object delivery medical system 300 according to this embodiment includes, in addition to the delivery system 200, an insertion assist member 50 for delivering the delivery catheter 30 into a biological lumen.

<Insertion aid>
The insertion assistance member 50 is an auxiliary tool that has a guidewire lumen 52 that passes from the tip end to the base end along the axial direction of the main body 51, and that assists in the insertion of the delivery catheter 30 into the aneurysm (inside the living body) along a guidewire that has been inserted into the biological lumen in advance.

The insertion assistance member 50 is inserted into and assembled with the delivery catheter 30 to prevent bending or the like when the delivery catheter 30 is inserted into the body lumen. The guidewire lumen 52 has a smaller inner diameter than the sheath lumen 32 of the delivery catheter 30. This reduces the axial misalignment of the delivery catheter 30 with respect to the guidewire when delivering the delivery catheter 30 into the aneurysm (inside the body), making delivery easier.

The material of the insertion assist member 50 is not particularly limited as long as it is harder and more flexible than the delivery catheter 30. Examples of suitable materials for the insertion assist member 50 include polyolefins such as polyethylene and polypropylene, polyesters such as polyamide and polyethylene terephthalate, fluororesins such as ETFE, PEEK (polyether ether ketone), and resin materials such as polyimide, and metal materials such as shape memory alloys, stainless steel, tantalum, titanium, platinum, gold, and tungsten.

[Action]
Next, the operation of the embolic material delivery medical system 300 according to this embodiment will be described with reference to FIGS. 9A to 9G as appropriate.

The following explanation is an example of the operation of the embolic material delivery medical system 300 when applied to endoleak embolization for stent graft insertion of abdominal aortic aneurysm (AAA), and the embolic material 10 used has a substantially circular cross-sectional shape as shown in FIG. 5A. In addition, in FIG. 9C to FIG. 9G, the inside of the aneurysm is designated as "A", the inside of the blood vessel is designated as "V", and the outside of the body is designated as "O", to allow the placement position of each device of the embolic material delivery medical system 300 to be systematically understood.

First, as a preoperative preparation step, as shown in FIG. 9A, the surgeon inserts the sheath 31 of the delivery catheter 30, into which the insertion assisting member 50 has been inserted, percutaneously into the biological lumen from the patient's limb that will be the puncture site via an introducer (for example, a member shown by a two-dot chain line in FIG. 9C), and delivers the distal end opening 31a of the delivery catheter 30 to the abdominal aortic aneurysm (hereinafter simply referred to as the "aneurysm"). Then, when the distal end opening 31a is delivered into the aneurysm, the surgeon removes the insertion assisting member 50. Note that the surgeon may deliver the delivery catheter 30 to the aneurysmal site by using a guide wire that has been inserted into the aneurysm beforehand, without using the insertion assisting member 50. In addition, the surgeon performs a priming operation on the delivery catheter 30 before introducing the delivery catheter 30 into the biological lumen.

Next, as shown in FIG. 9B, the surgeon inserts a catheter (stent graft device) with the stent graft SG compressed and inserted via an introducer into the biological lumen, and moves it to the aneurysmal affected area using a guide wire previously inserted into the aneurysm. The stent graft SG is then deployed and placed from the catheter at the affected area. As a result, as shown in FIG. 9B, the delivery catheter 30 is placed in the biological lumen with the tip of the delivery catheter 30 inserted between the legs of the stent graft SG and the vascular wall of the aneurysm, i.e., into the aneurysm, through the gap between the legs of the stent graft SG and the vascular wall, and the tip opening 31a is positioned within the aneurysm.

Next, as shown in FIG. 9C, an embolic material-loaded catheter 20M loaded with an embolic material 10 is prepared. FIG. 9C shows the state of the embolic material-loaded catheter 20M before it is attached to the delivery catheter 30.

Before attaching the embolus-loaded catheter 20M to the delivery catheter 30, the surgeon performs a priming operation on the embolus-loaded catheter 20M. Then, as shown in FIG. 9D, the surgeon attaches the tip connection part 27 of the embolus-loaded catheter 20M to the base end of the sheath hub 33 of the delivery catheter 30. At this time, the axial center of the loading lumen 22 is aligned with the axial center of the sheath lumen 32.

Next, as shown in FIG. 9E, the surgeon inserts the tip of the pusher body 41 from the base end side of the base end hub 23 while holding the handle portion 42. The tip of the delivery pusher 40 inserted from the base end hub 23 abuts against the base end of the embolus 10 loaded in the embolus-loaded catheter 20M, and the surgeon's pushing operation pushes out and moves the embolus 10 into the sheath lumen 32 of the delivery catheter 30.

Then, as shown in FIG. 9F, the surgeon pushes out the delivery pusher 40 inserted from the base hub 23 to push the embolus 10 from the sheath lumen 32 into the aneurysm. At this time, when the sensing portion 44 of the pusher body 41 passes through the hemostasis valve 27, the sliding resistance of the delivery pusher 40 against the hemostasis valve 27 changes, so the surgeon can easily sense the timing when the tip of the embolus 10 is pushed out from the tip of the delivery lumen into the aneurysm. In addition, when the recognition portion 46 of the handle portion 42 passes through the hemostasis valve 27 of the embolus-loaded catheter 20M that serves as the hemostasis valve of the delivery catheter assembly, or abuts against the base hub 23 of the embolus-loaded catheter 20M that serves as the base end of the delivery catheter assembly, the sliding resistance of the delivery pusher 40 against the hemostasis valve 27 increases, so the surgeon can easily recognize the timing when the tip 41a of the pusher body 41 reaches the tip of the delivery lumen.

Next, as shown in FIG. 9G, the surgeon removes the now empty embolus-loaded catheter 20M together with the delivery pusher 40 from the delivery catheter 30. The delivery pusher 40 can be removed from the delivery catheter 30 while still inserted into the embolus-loaded catheter 20M. This completes the first insertion of the embolus 10 into the aneurysm. Note that during the insertion operation, the delivery pusher 40 may be pulled out of the embolus-loaded catheter 20M before the embolus-loaded catheter 20M is removed.

In endoleak embolization, the series of embolic material placement operations shown in Figures 9C to 9G are repeated until the required amount of embolic material 10 is loaded into the aneurysm. The required amount of embolic material 10 is calculated by calculating the volume of the aneurysm based on the patient's CT data, and subtracting from that value the volume of the stent graft SG when deployed in the aneurysm.

When the placement of the required amount of embolus 10 in the aneurysm is completed, the surgeon withdraws the delivery catheter 30 from the aneurysm and the biological lumen. At this time, the delivery catheter 30 may be withdrawn from the aneurysm and the biological lumen with the embolus-loaded catheter 20M attached to the delivery catheter 30 and the delivery pusher 40 inserted into the delivery catheter 30. Alternatively, before withdrawing the delivery catheter 30 from the aneurysm and the biological lumen, the delivery pusher 40 may be withdrawn from the delivery catheter 30 while detaching the embolus-loaded catheter 20M from the delivery catheter 30. Alternatively, before withdrawing the delivery catheter 30 from the aneurysm and the biological lumen, the delivery pusher 40 may be withdrawn from the delivery catheter 30 after withdrawing the embolus-loaded catheter 20M from the delivery catheter 30. In either case, the introducer is left in place within the biological lumen for the purpose of further expanding the stent graft SG with a balloon after placement of the embolus 10, contrast manipulation, etc.

Then, the embolus 10 placed in the aneurysm gradually swells as it comes into contact with the blood and other liquids in the aneurysm, and when it is fully expanded, the embolus 10 fills the space between the inner surface of the aneurysm and the outer surface of the stent graft, occluding the aneurysm. This prevents the aneurysm from rupturing.

The above-described embodiment can be modified as follows:

The following modified examples (or embodiments) can also be combined in any way without departing from the spirit of the present invention. In the modified examples (or embodiments) described below, the same reference numerals are used for components having the same functions as the above-described embodiments, and detailed descriptions are omitted. Configurations, members, etc. that are not specifically mentioned may be the same as those of the above-described embodiments.

(Modification of the first embodiment)
FIG. 10 is a diagram showing the configuration of a delivery pusher 400 and a delivery catheter assembly 100A according to a modification of the first embodiment.

The delivery catheter assembly 100A according to the modified example of the first embodiment differs from the first embodiment in the method of connecting the embolus-loaded catheter and the delivery catheter.

As shown in FIG. 10, the delivery catheter assembly 100A is composed of an embolic material-loaded catheter 20MA and a delivery catheter 30 capable of housing the catheter body 21A of the embolic material-loaded catheter 20MA in a sheath 31.

The delivery lumen into which the delivery pusher 400 is inserted is constituted by the loading lumen 22A of the embolus-loaded catheter 20MA, so the length of the pusher body 441 of the delivery pusher 400 is shorter than that of the first embodiment. Specifically, the length from the tip of the first insertion part of the delivery pusher 400 to the base end of the second insertion part is set to be equal to or greater than the length X5 from the base end (not shown) of the insertion passage of the base-end hub of the embolus-loaded catheter 20MA to the tip opening 21a of the catheter body 21A.

Therefore, at the timing when the tip of the embolus 10 is pushed out from the tip of the delivery catheter assembly 100A, the base end of the first insertion section 43 is located on the base end side of the hemostatic valve 27 of the catheter 20 (the sliding resistance changing structure that constitutes the sensing section 44 passes through the hemostatic valve 27), and the sliding resistance of the delivery pusher 400 against the hemostatic valve 27 of the catheter 20M loaded with the embolus changes. Therefore, the surgeon can easily determine the timing when the embolus 10 is pushed out from the tip of the delivery catheter assembly 100A.

Second Embodiment
In the first embodiment, the delivery pusher (medical instrument) has been described as a rod-shaped member that can be inserted into the delivery catheter assembly, but it can also be configured as follows: Fig. 11 is a diagram showing the configuration of a delivery pusher 500 according to a second embodiment, a delivery catheter 30 from which the embolus 10 has been moved from the embolus-loaded catheter 20M, and a catheter 20M loaded with embolus material from which the embolus 10 has been removed.

As shown in FIG. 12, the delivery pusher 500 according to the second embodiment is inserted only into the delivery catheter 30.

The delivery catheter 30 placed in the body lumen is connected to the embolus-loaded catheter 20M, and after the embolus 10 loaded in the loading lumen 22 of the embolus-loaded catheter 20M moves to the sheath lumen 32 of the delivery catheter 30, the embolus-loaded catheter 20M is removed.

The delivery lumen into which the delivery pusher 500 is inserted is constituted by the sheath lumen 32 of the delivery catheter 30, so the length of the pusher body 541 of the delivery pusher 500 is shorter than that of the first embodiment. Specifically, the length from the tip of the first insertion part of the delivery pusher 500 to the base end of the second insertion part is set to be equal to or greater than the length X6 from the base end (not shown) of the insertion passage of the base end hub of the delivery catheter 30 to the tip opening 31a of the delivery catheter 30.

Therefore, at the timing when the tip of the embolus 10 is pushed out from the tip of the delivery catheter 30, the sliding resistance changing structure that constitutes the sensing unit 44 passes through the hemostatic valve of the delivery catheter 30, and the sliding resistance of the delivery pusher 500 against the hemostatic valve of the delivery catheter 30 changes. Therefore, the surgeon can easily determine the timing when the embolus 10 is pushed out from the tip of the delivery catheter 30.

As described above, the medical device of the first embodiment is a delivery pusher 40 that is inserted into a delivery catheter assembly 100 including an embolus-loaded catheter 20M configured to be capable of being loaded with an embolus 10 to be inserted and placed in a living body, and a delivery catheter 30 that is connected to the embolus-loaded catheter 20M while placed in a living body lumen, and is used to push out the embolus 10 loaded in the embolus-loaded catheter 20M into the living body via the delivery catheter 30. The delivery pusher 40 has an elongated pusher body 41 that can be inserted into a delivery lumen defined by the delivery catheter assembly 100 and has an outer circumferential surface 41C that faces the delivery lumen, and a handle portion 42 that extends from a base end 41b of the pusher body 41 and has an outer circumferential surface 42C that is gripped by the surgeon when delivering the embolus 10 into a living body. The pusher body 41 has a first insertion portion 43 that extends from a tip 41a of the pusher body 41 and can be inserted into the delivery lumen, and a handle portion 42 that is disposed at the base end of the first insertion portion 43 and allows the surgeon to determine the timing at which the tip of the embolus 10 is pushed out from the tip of the delivery lumen into the living body. and a second insertion part 45 that extends from the base end of the sensing part 44 toward the base end 41b of the pusher body 41 and is configured to push the base end of the embolus 10 from the tip of the delivery lumen into the living body by being inserted into the delivery lumen. The sensing part 44 is configured to be able to pass through the hemostatic valve 27 provided at the base end of the embolus-loaded catheter 20M, and has a sliding resistance changing structure on the outer circumferential surface 41C of the pusher body 41 that changes the sliding resistance against the hemostatic valve 27 when the surgeon inserts the delivery pusher 40 into the delivery catheter assembly 100 and advances it.

With this configuration, at the timing when the tip of the embolus 10 is pushed out from the tip of the delivery catheter assembly 100, the base end of the first insertion section 43 is located on the base end side of the hemostasis valve 27 of the embolus-loaded catheter 20M (catheter 20) (the sliding resistance changing structure that constitutes the sensing section 44 passes through the hemostasis valve 27), and the sliding resistance of the delivery pusher 40 against the hemostasis valve 27 of the catheter 20 changes. Therefore, the surgeon can easily determine the timing when the embolus 10 is pushed out from the tip of the delivery catheter assembly 100.

The medical device according to the second embodiment is a delivery pusher 500 that connects an embolus-loaded catheter 20M configured to be capable of loading an embolus 10 to be inserted and placed in a living body to a delivery catheter 30 placed in a living body lumen, moves the embolus 10 loaded in the loading lumen 22 of the embolus-loaded catheter 20M to the delivery lumen (sheath lumen 32) of the delivery catheter 30, and then inserts the embolus-loaded catheter 20M into the delivery catheter 30 from which it has been removed, and pushes out the embolus 10 stored in the delivery catheter 30 into the living body. The delivery pusher 500 has an elongated pusher body 541 that can be inserted into the sheath lumen 32 of the delivery catheter 30 and has an outer circumferential surface facing the sheath lumen 32, and a handle portion 42 that extends from a base end of the pusher body 541 and has an outer circumferential surface that is gripped by an operator when delivering the embolus 10 into a living body. The pusher body 541 has a first insertion portion 43 that extends from a tip of the pusher body 541 and can be inserted into the sheath lumen 32 of the delivery catheter 30, and a handle portion 42 that is disposed at the base end of the first insertion portion 43 and has a timing at which the tip of the embolus 10 is pushed out from the tip of the sheath lumen 32 into the living body. and a second insertion part 45 that extends from the base end of the sensing part 44 to the base end of the pusher body 541 and is configured to push the base end of the embolus 10 from the tip of the sheath lumen 32 into the living body by being inserted into the sheath lumen 32. The sensing part 44 is configured to be able to pass through a hemostatic valve 27 provided at the base end of the embolus-loaded catheter 20M, and has a sliding resistance changing structure on the outer circumferential surface of the pusher body 541 that changes the sliding resistance against the hemostatic valve 27 when the surgeon inserts the delivery pusher 500 into the delivery catheter 30 and advances it.

With this configuration, at the timing when the tip of the embolus 10 is pushed out from the tip of the delivery catheter 30, the sliding resistance changing structure that constitutes the sensing unit 44 passes through the hemostatic valve of the delivery catheter 30, and the sliding resistance of the delivery pusher 500 against the hemostatic valve of the delivery catheter 30 changes. Therefore, the surgeon can easily determine the timing when the embolus 10 is pushed out from the tip of the delivery catheter 30.

The sensing unit 44 is also characterized by being disposed at a preset position between a first position L1, which is a length X1 of the embolus 10 when it is disposed in the delivery lumen from the base end 41b of the pusher body 41 toward the tip 41a of the pusher body 41, and a second position L2, which is a predetermined distance from the first position L1 toward the tip 41a of the pusher body 41.

According to this configuration, when the surgeon inserts the tip side of the first insertion part 43 into the delivery lumen and advances the delivery pusher 40 until the base end of the first insertion part 43 is located on the base end side of the hemostasis valve 27 of the catheter 20 (or the delivery catheter 30) (the sliding resistance change structure part constituting the sensing part 44 passes through the hemostasis valve 27), the tip of the embolus 10 can be protruded from the tip opening of the delivery catheter assembly 100 (the tip opening 31a of the delivery catheter 30). Also, when the surgeon advances the delivery pusher 40 until the base end of the second insertion part 45 passes through the hemostasis valve 27, the entire embolus 10 can be protruded from the tip opening of the delivery catheter assembly 100.

The sliding resistance change structure of the sensing unit 44 is provided along the circumferential direction of the pusher body 41.

This configuration makes it possible to increase the change in sliding resistance against the hemostasis valve 27 when the sensing unit 44 (sliding resistance change structure unit) is passed through the hemostasis valve 27 of the catheter 20.

The sliding resistance change structure of the sensing unit 44 has a plurality of sliding resistance change structure parts arranged along the axial direction of the pusher body 41, and each of the plurality of sliding resistance change structure parts (sliding resistance change structure parts 44A to 44D) is arranged toward the base end 41b of the pusher body 41, with one of the plurality of sliding resistance change structure parts (sliding resistance change structure part 44A) located between the first position L1 and the second position L2 as a reference.

With this configuration, at the timing when the tip of the embolus 10 is pushed out from the tip of the delivery catheter assembly 100, the sliding resistance changing structure 44A constituting the sensing unit 44 passes through the hemostasis valve 27 of the catheter 20, and the sliding resistance of the delivery pusher 40 against the hemostasis valve 27 changes. The sliding resistance of the delivery pusher 40 against the hemostasis valve 27 continues to occur until the sliding resistance changing structure parts 44A to 44D pass through the hemostasis valve 27. Therefore, the surgeon can easily determine the timing when the embolus 10 is pushed out from the tip of the delivery catheter assembly 100.

In addition, the sensing portion 44 has a recess 44k (first recess) that is recessed from the outer peripheral surface 41C of the pusher body 41 as a sliding resistance change structure.

With this configuration, when the tip of the embolus 10 is pushed out from the tip of the delivery catheter assembly 100, the sliding resistance changing structure that constitutes the sensing unit 44 passes through the hemostasis valve 27 of the catheter 20, and the sliding resistance of the delivery pusher 40 against the hemostasis valve 27 decreases.

In addition, the sensing portion 44P of the delivery pusher 40P has a protrusion 44l (first protrusion) that protrudes from the outer circumferential surface of the pusher body 41P as a sliding resistance changing structure.

With this configuration, when the tip of the embolus 10 is pushed out from the tip of the delivery catheter assembly 100, the sliding resistance changing structure constituting the sensing unit 44P passes through the hemostasis valve 27 of the catheter 20, and the sliding resistance of the delivery pusher 40P against the hemostasis valve 27 increases.

The protrusion 44m of the sensing unit 44Q according to the modified example of the protrusion 44l has a tapered shape configured such that the protruding length X4 from the outer peripheral surface of the pusher body 41Q gradually increases from the base end 44mb of the protrusion 44m to the tip 44ma of the protrusion 44m.

This configuration ensures that the amount of change in sliding resistance against the hemostasis valve 27 that occurs when the surgeon advances the delivery pusher 40Q is maintained, while suppressing the amount of change in sliding resistance against the hemostasis valve 27 that occurs when the surgeon retracts the delivery pusher 40Q. This allows the surgeon to sense the timing at which the tip of the embolus 10 is pushed out from the tip of the delivery catheter assembly 100 by the delivery pusher 40Q, and allows the surgeon to easily pull out the delivery pusher 40Q from the delivery catheter assembly 100.

In addition, the sensing portion 44R of the delivery pusher 40R has a high sliding resistance structure portion that has a sliding resistance change structure in which the sliding resistance against the hemostasis valve 27 is higher than that of the insertion portion.

This configuration allows the surgeon to recognize the difference in slipperiness of the delivery pusher 40R.

The handle portion 42 also includes a recognition portion 46 adjacent to the base end of the second insertion portion 45 and configured to allow the surgeon to recognize the timing when the tip 41a of the pusher body 41 reaches the tip of the delivery lumen.

With this configuration, when the tip 41a of the pusher body 41 reaches the tip of the delivery lumen, the sliding resistance changing structure that constitutes the recognition unit 46 passes through the hemostasis valve 27, changing the sliding resistance of the delivery pusher 40 against the hemostasis valve 27 of the catheter 20. Therefore, the surgeon can easily determine the timing when the tip 41a of the pusher body 41 reaches the tip of the delivery lumen.

The recognition section 46 (or the recognition section 46S of the delivery pusher 40S) is configured so that the sliding resistance against the hemostasis valve 27 of the catheter 20 into which the pusher body 41 is inserted is higher than that of the second insertion section 45, and has an inclined section 46k (second recess) that is provided so that the outer circumferential surface 42C of the handle section 42 is recessed, and/or a convex section 46l (second convex section) that is provided so that it protrudes from the outer circumferential surface 42C of the handle section 42.

With this configuration, when the tip 41a of the pusher body 41 reaches the tip of the delivery lumen, the sliding resistance changing structure constituting the recognition unit passes through the hemostasis valve 37 of the delivery catheter 30, and the sliding resistance of the delivery pusher 500 against the hemostasis valve 27 of the catheter 20 changes.

The recognition portion 46T of the delivery pusher 40T is configured to be unable to pass through the hemostasis valve 27 of the catheter 20 into which the pusher body 41T is inserted, and has a protrusion 46m (third protrusion, large diameter umbrella portion 42Ta) that protrudes from the outer circumferential surface of the handle portion 42T.

With this configuration, when the delivery pusher 40T is inserted into the delivery catheter assembly 100, the large diameter umbrella portion 42Ta is not inserted into the insertion passage 23a of the base end hub 23, so the insertion length of the delivery pusher 40 can be limited. In addition, since the large diameter umbrella portion 42Ta prevents the handle portion 42T from entering the base end hub 23, when the operation of pushing out the embolus 10 by the delivery pusher 40T is completed, the handle portion 42T can be easily pulled out while still inserted, along with the removal operation of the catheter 20, making the removal operation easier.

In addition, the recognition portion 46U of the delivery pusher 40U has a marker portion 46n that is a different color from the second insertion portion 45U.

With this configuration, the surgeon can easily recognize that the tip of the pusher body 41U is approaching the tip of the delivery catheter assembly 100 by visually checking the marker portion 46n.

The delivery system also includes the delivery pusher described above, a loading catheter configured to be capable of loading the embolus 10, and a delivery catheter to which the loading catheter is attached and detached.

With this configuration, when the tip of the embolus 10 is pushed out from the tip of the catheter into which the delivery catheter 30 is inserted, the sliding resistance changing structure that constitutes the sensing unit 44 passes through the hemostatic valve of the catheter, and the sliding resistance of the delivery pusher against the hemostatic valve of the catheter changes. Therefore, the surgeon can easily determine the timing when the embolus 10 is pushed out from the tip of the catheter.

10 Embolism,
20 Catheter (loading catheter),
20M, 20MA embolic material loaded catheter,
30 delivery catheter,
40, 400, 500 Delivery pusher,
41, 441, 541 Pusher body,
42 Handle portion,
43 first insertion part,
44 sensing unit,
45 second insertion part,
46 Recognition unit,
100, 100A Delivery catheter assembly,
200 Delivery System,
300 Embolic material delivery medical system,
In the X-axis direction,
Y: width direction,
Z Height direction.

Claims (14)

a delivery catheter assembly including an embolus-loaded catheter configured to be capable of being loaded with an embolus to be inserted and placed in a living body, and a delivery catheter connected to the embolus-loaded catheter in a state in which the catheter is placed in a living body lumen;
a delivery pusher for pushing the embolus loaded in the embolus-loaded catheter into the living body through the delivery catheter,
an elongated pusher body insertable into a delivery lumen defined by the delivery catheter assembly and having an outer circumferential surface facing the delivery lumen;
a handle portion extending from a base end of the pusher body and having an outer circumferential surface that is gripped by an operator when delivering the embolus into a living body;
The pusher body includes:
A first insertion portion extending from a tip of the pusher body and insertable into the delivery lumen;
a sensing unit disposed at a base end of the first insertion section and configured to allow an operator to sense a timing when a tip of the embolus is pushed out into the living body from a tip of the delivery lumen;
a second insertion section configured to extend from a proximal end of the sensing section toward a proximal end of the pusher body and to push the proximal end of the embolus from the distal end of the delivery lumen into the living body by being inserted into the delivery lumen;
the sensing unit is configured to be able to pass through a hemostatic valve provided at the base end of the embolus-loaded catheter, and the medical device has a sliding resistance changing structure on the outer surface of the pusher body that changes the sliding resistance against the hemostatic valve when the surgeon inserts the delivery pusher into the delivery catheter assembly and advances it forward. a catheter loaded with an embolus material that is configured to be capable of being loaded with an embolus material to be inserted and placed in a living body is connected to a delivery catheter placed in a living body lumen, and the embolus material loaded in the loading lumen of the catheter loaded with the embolus material is moved to a delivery lumen of the delivery catheter, and then the catheter loaded with the embolus material is inserted into the delivery catheter in a detached state;
A delivery pusher for pushing the embolus housed in the delivery catheter into the living body,
an elongated pusher body that is insertable into the delivery lumen of the delivery catheter and has an outer circumferential surface that faces the delivery lumen;
a handle portion extending from a base end of the pusher body and having an outer circumferential surface that is gripped by an operator when delivering the embolus into a living body;
The pusher body includes:
a first insertion portion extending from a tip of the pusher body and insertable into the delivery lumen of the delivery catheter;
a sensing unit disposed at a base end of the insertion unit and configured to allow an operator to sense a timing when a tip of the embolus is pushed out into the living body from a tip of the delivery lumen;
a second insertion section configured to extend from a proximal end of the sensing section to a proximal end of the pusher body and to push the proximal end of the embolus from the distal end of the delivery lumen into the living body by being inserted into the delivery lumen;
Equipped with
the sensing unit is configured to be able to pass through a hemostatic valve provided at the base end of the embolus-loaded catheter, and the medical device has a sliding resistance changing structure on the outer surface of the pusher body that changes the sliding resistance against the hemostatic valve when an operator inserts the delivery pusher into the delivery catheter and advances it forward. The medical device according to claim 1 or 2, characterized in that the sensing unit is disposed at a preset position between a first position that is a length of the embolus when it is disposed in the delivery lumen from the base end of the pusher body toward the tip of the pusher body, and a second position that is a predetermined distance away from the first position toward the tip of the pusher body. The medical device according to claim 3, wherein the sliding resistance change structure of the sensing unit is provided along the circumferential direction of the pusher body. the sliding resistance change structure of the sensing unit has a plurality of sliding resistance change structure portions provided along the axial direction of the pusher body,
5. The medical instrument according to claim 3, wherein each of the plurality of sliding resistance change structure parts is provided toward the base end of the pusher body with respect to one of the plurality of sliding resistance change structure parts that is disposed between the first position and the second position as a reference. The medical device according to any one of claims 3 to 5, wherein the sensing section has a first recess that is recessed from the outer circumferential surface of the pusher body as the sliding resistance changing structure. The medical device according to any one of claims 3 to 6, wherein the sensing unit has a first protrusion that protrudes from the outer circumferential surface of the pusher body as the sliding resistance changing structure. The medical device according to claim 7, wherein the first protrusion has a tapered shape configured such that the length of the first protrusion protruding from the outer circumferential surface of the pusher body gradually increases from the base end of the first protrusion to the tip of the first protrusion. The medical device according to any one of claims 3 to 5, wherein the sensing section has a high sliding resistance structure section as the sliding resistance changing structure, the sliding resistance of which against the hemostasis valve is higher than that of the insertion section. The medical instrument according to any one of claims 1 to 9, wherein the handle portion is adjacent to the base end of the second insertion portion and includes a recognition portion configured to allow the surgeon to recognize the timing when the tip of the pusher body reaches the tip of the delivery lumen. The medical device according to claim 10, wherein the recognition section is configured so that the sliding resistance against the hemostasis valve when the pusher body passes through the hemostasis valve of the inserted catheter is higher than that of the second insertion section, and the recognition section has a second recess provided so as to recess the outer circumferential surface of the handle section and/or a second protrusion provided so as to protrude from the outer circumferential surface of the handle section. The medical device according to claim 10 or 11, wherein the recognition portion is configured to be unable to pass through the hemostasis valve of the catheter into which the pusher body is inserted, and has a third protrusion provided to protrude from the outer circumferential surface of the handle portion. The medical device according to any one of claims 10 to 12, wherein the recognition section has a marker section of a different color than the second insertion section. A delivery pusher according to any one of claims 1 to 13;
A loading catheter configured to be capable of loading the embolus;
a delivery catheter to which the loading catheter is detached.