JPH06225942A - Catheter for embolectomy - Google Patents

Abstract

PURPOSE:To achieve embolectomy of aneurysm safely and accurately by providing a pinning means for forming a liquid material as a filamentous embolus at the tip part of a catheter having a path for introducing the liquid material. CONSTITUTION:A catheter 1 for emboletomy is made up of a catheter body part 10, the tip part 20 thereof and the base part 30 thereof. In operation, a liquid material introduction port 32 has a container for storing a liquid material connected thereto as opening of a base end part and a pressure is applied to the liquid material by a pressure loading means to discharge a continuous fine- diameter material from the tip end part 20. The catheter body part 10 has a path 50 to introduce the liquid material and a path 60 to insert a guide wire, an observation scope or the like. The tip part 20 of the catheter is provided with a discharge nozzle 54 as spinning means having a discharge port 52 which communicates from the path 50 for introducing the liquid material to spin the liquid material introduced by discharging it and an opening 62 of a path 60 through which is inserted a guide wire, an observation scope or the like.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an embolization catheter used for vascular embolization.

[0002]

2. Description of the Related Art As a general treatment for cerebral aneurysms, there is a method of surgically performing craniotomy and clipping of the aneurysm, but this cannot be denied the risk of great surgical invasion and complications. Therefore, in order to improve the treatment results of inoperable or difficult cerebrovascular lesions such as large aneurysms, and to reduce the physical and psychological and financial burden of patients, surgical operation is not applied and vascular catheter is used. Endovascular surgery has become popular in recent years (Katsuya Goto, Neurosurgeons 9, 2
29-239, 1990).

For example, in the treatment of cerebrovascular accidents, a micro catheter is superselectively inserted into an affected part of a cerebral artery, and an embolus substance introduced by the catheter occludes a cerebral aneurysm or the like for treatment. It is an object.

Since the cerebral blood vessel has a thinner blood vessel wall than other portions, the resistance to lateral pressure of the blood flow is weak, and the blood vessel travels intricately in the skull, especially due to the stress applied to the bifurcation. Especially in patients with high blood pressure, disorders are likely to occur. A cerebral aneurysm is an aneurysm that one in 100 adults has in the arterial vascular system according to autopsy statistics, has a wide shape distribution from a diameter of about 1 mm to a huge size of 20 mm or more, and the site of occurrence is the Willis artery ring ring) and spans multiple branches of the cerebral artery. When it ruptures, it causes serious cerebrovascular disorders such as subarachnoid hemorrhage and intracerebral hemorrhage, and when it becomes huge, it causes cranial nerve compression symptoms. Arteriovenous malformations are the most common cerebrovascular malformations,
It is also well known and consists of a collection of vessels with tortuous, dilated inflow and outflow vessels and arteriovenous anastomosis in between. It is clinically important as a cause of intracerebral hemorrhage, subarachnoid hemorrhage, epilepsy, and progressive loss of neurological function, which occurs at a relatively young age.

[0005] Embolization is a treatment in which such a cerebral artery lesion is occluded with an embolizing substance, blood flow in the lesion is stopped to solidify the affected area, and if necessary, the solidified affected area is removed. To do.

Embolization plays a central role in the treatment of cerebral arteriovenous malformations (Goto K. et al. Neuro.
radiology 33 [Suppl] 193-194 1991), and it is expected that a similar situation will occur for cerebral aneurysms in the near future (Katsuya Goto, History of Medicine 153 : 635 1990). Therefore, various embolic materials have been studied.

[0007] Conventionally, a cyanoacrylate-based material has been often used as a liquid for occluding a vascular lesion site (J. Biomed, Mater. Res., 17 , 167-177 (1983) MC Har.
pers and others).

[0008] In recent years, ethylene - dimethyl sulfoxide (D vinyl alcohol copolymer (Eval ^R)
DMSO in blood using MSO) solution as a material for embolization
It has been proposed to diffuse SO and deposit EVAL ^R to occlude blood vessels (medical tribune, 1
October 26, 989, pp. 46-47).

[0009] On the other hand, a method of inflating a balloon (separable balloon) that can be separated inside an aneurysm using a catheter to close the aneurysm and leaving the balloon in the aneurysm is also known (Journal of Neurosurgery, 41 , 125-14
5 (1974), FASerbinenko).

In addition, metal coils (minicoils), polyvinyl alcohol (PVA) sponges, alcohols, sutures and the like have been used as the conventional ones according to the therapeutic purpose.

In the conventional materials of cyanoacrylate type,
It rapidly solidifies and polymerizes in blood vessels, making it difficult to inject embolic substances, and this agent, which has a strong adhesive action, prevents catheters from being glued into cerebral blood vessels. It has to be removed all at once, is difficult to handle, and cannot be re-injected even if the occlusion condition is insufficient. In addition, there is a problem that the irritation to the blood vessel wall is large and causes a strong inflammatory reaction.

[0012] EVAL ^R system used in dissolved in DMSO solvent, in the center of EVAL ^R precipitated touching the bloody,
When the solvent remains forever or when it is used for embolization of an aneurysm, there is a problem that the portion protruding from the aneurysm outlet into the blood vessel adheres along the flow of the bifurcation.

The safety of DMSO as a solvent has not been established (11th Annual Meeting of the Japan Society for Biomaterials (1989) 68, II-22 Hiroo Iwata et al.) In the case of the method of directly injecting into the aneurysm through the catheter as described above, it is not always the best solvent.

A detachable balloon is often used for embolization of an aneurysm. However, when a balloon is used, the reaction between the balloon and the inner wall of the aneurysm is weak, so the inner cavity of the aneurysm cannot be sufficiently filled. There is a high risk of recurrence if any lumen remains. If the balloon is inflated as much as possible to fill the lumen of the aneurysm, the internal pressure of the balloon increases and the shape of the aneurysm is changed, which may cause the aneurysm to rupture. Also, traction must be applied when disconnecting the balloon from the catheter, again increasing the risk of aneurysm rupture.

At present, it is difficult to completely block the neck of the aneurysm even with a method using a detachable balloon, a mini-coil, etc., and a proximal occlusion method for obstructing a part of the parent artery is often performed (medical history 154. (7) .432. (199
0) Akira Takahashi), but this method requires sacrificing the parent artery, which puts the brain at risk of impaired blood flow.
There is also a method of using a detachable balloon and a mini coil for embolization of a giant aneurysm (Katsuya Goto, Abstracts of the Japanese Angiographic IVR Research Group, 1991), but it requires a lot of expensive mini coils and takes a long time. The depressurizing effect is poor, that is, the packing density is low, and it is difficult to reduce the pressure inside the aneurysm immediately after placement.

In addition, materials such as PVA granules, alcohol, and sutures are difficult to handle and have many therapeutic problems such as insufficient therapeutic effect.

[0017]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to propose an embolization catheter capable of safely and reliably performing embolization of an aneurysm. A further object of the present invention is to propose an embolization catheter capable of forming an embolization material capable of suppressing scattering of small pieces into blood vessels. A further object of the present invention is to propose an embolization catheter capable of forming a filamentous embolus. Another object of the present invention is to provide an embolization catheter capable of forming a vascular lesion embolization material in which side effects of solvents are suppressed as much as possible. Further, an object of the present invention is to provide an embolization catheter that has a high packing density and can reduce the pressure inside the aneurysm immediately after placement.

[0018]

These objects are met by the embolization catheter of the present invention. That is, the above-mentioned object is achieved by an embolization catheter having a passage for introducing a liquid substance, which has a spinning means at its distal end for forming the liquid substance as a thread-like embolic material. The passage for introducing the liquid substance preferably has openings at the distal end and the proximal end of the catheter.

The catheter for embolization according to the present invention preferably has at least one other passage separated from the passage for introducing the liquid substance. Further, it is desirable that the passage for introducing the liquid substance be opened at the distal end portion and the proximal end portion of the catheter. Further, it is desirable to further have at least one other passage separated from the passage for introducing the liquid substance.

Further, it is desirable that the spinning means has a discharging means. The liquid substance is composed of a reactive liquid substance and another liquid substance that cures and cures the reactive liquid substance, and is introduced to the tip through passages for introducing independent liquid substances, and the spinning means is a reactive liquid substance. It is desirable to form a thread-like embolic substance by mixing with the other liquid substance that reacts and cures the reactive liquid substance.

In the catheter for embolization according to the present invention, the liquid substance is a photoreactive liquid substance which is cured by irradiation with light.
It is preferable that the spinning means has a light irradiation means for reacting and curing the photoreactive substance. It is preferable that the liquid substance forms a filamentous embolic substance by shear stress, and the spinning means has a shear stress applying mechanism that applies shear stress to the liquid substance. The thickness of the spun yarn is preferably 1 to 100 denier.

The catheter for embolization according to the present invention comprises a reservoir portion inside the catheter, a pressure load means for applying a pressure to the reservoir portion, and a passage for communicating the outside of the catheter with the reservoir portion.
And a means for changing the movable liquid substance stored in the storage portion into a filamentous continuous body. Furthermore, the embolization catheter of the present invention has a main body that is relatively hard and a distal end that is relatively flexible, and forms a filamentous embolus from the distal end.

The catheter for embolization of the present invention preferably has a coating layer having biocompatibility and lubricity on the surface of the catheter. Furthermore, it is desirable to have a coating layer having antithrombogenicity and hydrophilicity on the surface of the catheter. It is desirable that the tip of the liquid substance passage has a reduced diameter.

The catheter for embolization according to the present invention comprises a forming portion for forming a filamentous embolic substance from the tip of the catheter, guiding the catheter to a desired site, and using the filamentous embolic substance formed by the forming portion. It is made by solidifying blood.

The filamentous embolic material formed by the catheter for embolization of the present invention can be appropriately used as long as it is a continuous thin substance as long as it does not defeat the purpose of the present invention.

The embolization catheter of the present invention can be used not only for embolization of cerebral aneurysms but also for aneurysms other than cerebral blood vessels such as aortic aneurysms and varices such as esophageal varices. In addition, it can be used as a catheter for embolization and filling of a lumen or a body cavity, such as for filling a defective portion after excision of a tissue such as cancer tumor by endoscopic surgery.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embolization catheter of the present invention will be described below with reference to preferred embodiments.

The embolization catheter 1 shown in FIG. 1 (a) of the present invention comprises a catheter body 10 and a catheter tip 2.
0 and a catheter base (operation part) 30.
The base 30 comprises a hub 36 composed of a liquid substance introduction port 32 and a guide wire port 34. At the time of use, the liquid substance introduction port 32 is connected to a container in which the liquid substance is stored as a base end opening, and a continuous small diameter product is discharged from the tip portion 20 by applying pressure to the liquid substance by a pressure load means as described later. To do.

FIG. 1B is a sectional view of the catheter body 10. As shown in this figure, the catheter body 10 has a passage 50 for introducing a liquid substance, that is, a passage (lumen) for introducing a liquid substance from the introduction port 32 of the catheter base 30 and supplying it from the tip of the catheter 1 to the outside.
50 and a passage (lumen) 60 through which a guide wire or an observation mirror is inserted. The catheter 1
Has a coating layer having biocompatibility and lubricity (not shown) on its surface. The coating layer having biocompatibility and lubricity enables prevention of thrombus formation on the surface of the catheter, prevention of damage to the intima of the blood vessel by the catheter, and smooth running in the blood vessel by reducing friction with the inner wall of the blood vessel.

FIG. 2 is a sectional view showing a boundary portion between the main body portion 10 and the distal end portion 20 of the embolization catheter 1 of the present invention.
In FIG. 2A, the left side of the drawing is the tip portion 20 of the catheter 1, and the right side is the body portion 10. The main body 10 is
The inner layer portion 22 is provided inside and the outer layer portion 12 is provided outside in the radial direction of the cross section. In the body portion 10, the outer layer portion 12
The outer diameter and the thickness of the are substantially the same in the axial direction. The outer diameter of the inner layer portion 22 is also substantially the same in the axial direction. The tip portion 20 is the main body portion 10.
The inner layer portion 22 extends to form the outer surface of the tip portion 20, and the outer layer portion 12 has the tip located at the base end of the tip portion 20 and does not cover the tip portion 20. The outer layer portion 12 is formed of a hard material having a relatively high rigidity, and the inner layer portion 22 is formed of a relatively flexible material. A passage 50 for introducing a liquid substance is formed in the inner layer portion 22. further,
The inner layer portion 22 is provided with a passage 60 for inserting a guide wire or an observation mirror as another passage separated from the passage 50 for introducing the liquid substance.

The outer layer portion 12 has a substantially uniform thickness near the tip 121 thereof, and is thin so that the outer diameter becomes smaller toward the tip, and compared with the main body portion 10 having the outer layer portion 12 having relatively high rigidity. The physical flexibility (rigidity) of only the physically flexible inner layer portion 22 with the tip portion 20 is buffered from being extremely changed. The tip portion 20 is flexible, the main body portion 10 has high rigidity, and since the tip portion 20 has a boundary portion where flexibility increases in the tip direction, bending of the boundary portion can be prevented. In addition, near the tip of the outer layer portion 1
The inner surface of 21 is provided with spiral or ring-shaped cuts to the extent that they do not penetrate to the outside, so that kink can be further prevented. Furthermore, it becomes difficult to come off when the outer surface of the inner layer portion 22 and the inner surface near the tip 121 are fusion-bonded by a spiral or annular cut or roughening of the inner surface. The inner layer portion 22 of the tip portion 20 is configured such that the outer diameter thereof is substantially the same or becomes smaller toward the tip.

In FIG. 2B, as in FIG. 2A, the left side of the drawing is the tip 20 of the catheter 1, and the right side is the main body 1.
0, and the same configurations are given the same numbers. Body 1
0 has an inner layer portion 22 on the inner side and an outer layer portion 12 on the outer side in the radial direction of the cross section. In the body portion 10, the outer diameter and the thickness of the outer layer portion 12 are substantially the same in the axial direction. Inner layer 22
The outer diameter of is also substantially the same in the axial direction. The tip portion 20 is formed by the outer layer portion 12 of the main body portion 10 extending from the tip side of the inner layer portion 22, and the inner layer portion 12 has its tip 220 as a terminal end. The outer layer portion 12 is made of a relatively flexible material, and the inner layer portion 22 is made of a material having a relatively high rigidity. A passage 50 for introducing a liquid substance and a passage 60 for inserting a guide wire or an observation mirror are continuously provided in the outer layer portion 12 of the tip portion 20 of the inner layer portion 22 of the main body portion 10 in the axial direction.

A portion 222 near the tip of the inner layer portion 22 of the main body portion has an outer diameter that decreases toward the tip, so that the main body portion 20 having the inner layer portion 22 having a relatively high rigidity and the outer layer portion 1 that is relatively flexible.
Kink is prevented by buffering the extreme change in the physical properties (rigidity) with the tip portion 10 of only 2. Further, the outer surface near the tip 222 of the inner layer portion 22 is provided with a spiral or ring-shaped notch so as not to penetrate the passages 50 and 60, thereby increasing the flexibility in the tip direction and further increasing the kink. It can be prevented. It becomes difficult for the inner surface of the outer layer portion 12 and the outer surface near the tip 222 to come off when they are fused by a spiral or annular cut or roughening of the inner surface. The inner layer portion 22 of the tip portion 20 is configured such that the outer diameter thereof is substantially the same or becomes smaller toward the tip.

FIG. 3 shows the distal end portion 20 of the embolization catheter 1 of the present invention. At the tip 20 of the catheter,
Lumen (passage) for introducing liquid substance as spinning means
A discharge nozzle 54 having a discharge port 52 that communicates with 50 to discharge and form the introduced liquid substance and spins it, and a lumen (passage) 60 through which a guide wire or an observation mirror is inserted.
An opening 62 is provided. Catheter tip 20
Has an outer diameter of about 1 mm.

The discharge nozzle 54 is formed so as to become smaller from the inner diameter of the lumen 50 for introducing the liquid substance to the inner diameter of the discharge port 52. This is to form a filamentous plug having a desired outer diameter and to increase the speed at which the introduced liquid substance is pressed and discharged from the discharge port 52 to the outside. By providing the discharge nozzle 54 as the spinning means, it is possible to form a continuous solid material having a small diameter. As the discharge nozzle, lumen 50
If the opening is substantially smaller than the inner diameter of the above, it can be used even if it is not tapered and has a thread-like shape.

FIG. 4 shows a first modification of the distal end portion 20 of the catheter 1 of the present invention shown in FIG. At the distal end portion 20, the lumen 60 through which a guide wire or an observation mirror is inserted and the opening portion 62 are the same as in the embodiment of FIG. 3, but the discharge nozzle 54 is different. That is, the discharge nozzle 54 of FIG. 4 has a portion 54a whose diameter gradually decreases from the inner diameter of the lumen (passage) 50 for introducing the liquid substance in the distal direction, and the tip has a substantially constant inner diameter. Also, it is composed of a discharge passage 54b having a small inner diameter and a discharge port 52 at the tip thereof to form a spinning means. By providing the discharge passage 54 with a predetermined length, it has an effect of keeping the outer diameter of the embolic substance discharged from the discharge port 52 and formed into a filament shape close to a constant value. By providing the discharge nozzle 54, a continuous solid material having a small diameter can be formed.

FIG. 5 shows a second modification of the distal end portion 20 of the catheter 1 of the present invention shown in FIG. In the discharge nozzle 54 as the spinning means in FIG. 5A, a portion 54a where the diameter gradually decreases from the inner diameter of the lumen (passage) 50 for introducing the liquid substance in the distal direction and the pressure increases from the lumen 50 side. In addition, due to the elasticity of the material (resin) formed by the distal end portion 20 of the catheter, a passage is formed and a closed passage 54c is formed in which the embolic substance is formed in a filament form from the discharge port 52.

FIG. 5 (b) is a sectional view of the tip portion 20 of FIG. 5 (a). The discharge port 52 and the closed passage 54c are normally closed, and the lumen 50 is filled with a liquid substance that is a raw material of the embolization substance, and when the internal pressure increases, the inner wall of the portion 54a whose diameter gradually decreases in the distal direction is formed. A force is applied to form the closed passage 54c as shown by the broken line in the figure. Similarly, the closed discharge port 52 is also expanded, and the liquid substance is spun into a filamentous substance which is a solid yarn through the passage formed by the closed passage 54c and the discharge port 52. If the liquid substance is one that comes into contact with blood and forms a thread-like shape,
It is preferable that the liquid substance and the blood in the aneurysm are not in contact with each other until spinning. In particular, when a solution in which a solute is dissolved in a solvent is used as a liquid substance, the solvent is dispersed and the solute is deposited to form an embolus, so that contact with blood leads to dispersion of the solvent. If the solute is not soluble in blood, the solute is deposited and forms. Therefore, it is preferable that the blood-insoluble solute is not in contact with blood before the start of spinning. When the internal pressure is reduced, the occlusion passage 54c is closed, so that the embolization operation can be restarted at any time.

FIG. 6 is a distal end perspective view showing another embodiment of the embolization catheter 1 of the present invention. In this embodiment, the basic structure of the catheter body, the catheter tip and the catheter base is the same as the catheter of FIG. 1 (a). Further, any of the structures shown in FIG. 2 can be adopted for the boundary portion between the tip portion and the main body portion. Further, a passage (lumen) 60 through which a guide wire or an observation mirror is inserted,
A catheter 70 for forming a thread-like embolic substance is inserted into a passage (lumen) 56 that extends from the catheter base portion to the main body portion and the distal end portion. The thread-shaped embolus substance forming catheter 70 is configured such that the distal end portion 72 can be freely drawn into the lumen 56 and can be made to project from the lumen 56 by a desired length. The tip portion 72 is tapered and tapered. The catheter 70 has a lumen 74 that communicates in the axial direction from a base end (not shown) to a tip 72. The lumen 74 is a passage for introducing a liquid substance and forming a filamentous embolic material from the tip portion 72. The inner diameter on the tip side of the lumen 74 is gradually reduced, and serves as a nozzle for forming a filamentous embolic material as a spinning means. The tip portion 72 is opened, and the liquid substance having the increased pressure in the lumen 74 is continuously discharged from the opening portion.

In order to make it easy to confirm the position of the tip portion 72, it is desirable to provide an X-ray contrast member made of gold or platinum. By providing the filamentous embolus substance forming catheter 70 slidably with the catheter 1, the position of the distal end 72 of the filamentous embolus substance forming catheter can be changed even in the aneurysm in which the catheter 1 is placed. The thread ball can be densely filled from the inside of the aneurysm to the aneurysm opening, and the position can be easily confirmed by providing the contrast member at the tip portion 72.

FIG. 7 shows the distal end portion of another embodiment of the embolization catheter 1 of the present invention. 7A is a cross-sectional view of the tip portion, and FIG. 7B is a front view of the tip portion. This embodiment has the same basic configuration as the catheter body, the catheter tip and the catheter base, but has a lumen (passage) for introducing a liquid substance.
The tip end side of 50 is closed by an elastic member 80. At the base end portion of the elastic member 80, a so-called conical space 82 is formed coaxially with the elastic member 80 such that the diameter is tapered toward the distal end side. The tip of the apex of the conical space 82 is a closed passage, and a minute passage is formed by increasing the pressure from the side of the conical space 82, and the liquid substance in the lumen 50 is ejected from the ejection opening 84 to form a filament. . The discharge port 84 of this catheter can be guided into the aneurysm using the guide wire and the lumen 50. The elastic member 80 has elasticity to such an extent that the guide wire can be inserted / removed. The difference from the embodiment of FIG. 5 is that the closing member is provided as a separate member. By using a separate member, the elastic force of the elastic member can be selected without being restricted by the material of the catheter. Similar to the embodiment of FIG. 5, the elastic member 80 prevents the contact between the liquid substance before spinning and blood, so that the spinning proceeds smoothly. Elastic member 80
Is closed when the internal pressure of the lumen 50 is below a predetermined value.
By providing a gold or platinum X-ray contrast member at the tip of the catheter, it becomes easy to confirm the position of the catheter tip while performing embolization under fluoroscopy.

As the liquid substance used in this embodiment,
A solute resin insoluble in water (blood) is dissolved in an organic solvent, and the solvent is dispersed in blood to precipitate the solute. As the combination (solute / solvent), ethylene-vinyl alcohol copolymer / dimethyl sulfoxide, cellulose acetate resin (CAP) / ethanol, ethylene-vinyl alcohol copolymer / 50% normal propanol and the like can be used. The concentration of the solute resin is 0.2 to 20%, preferably 1 to 10%
Is. If it is less than 0.2%, the dispersion of the solvent does not proceed well when discharged, and there is a risk that it will not form a thread.
If it exceeds%, the viscosity is too high and there is a possibility that the ink cannot be discharged from the discharge port.

Solvent is dispersed in blood and solute is deposited. A liquid substance having a speed is made into a thin thread to some extent, whereby the solvent is quickly dispersed and the solute is easily deposited,
It is molded as a continuous product without breaking. Neurosurgeons ( 9 , 229-2)
39, 1990). As the photograph is shown in No. 1, it becomes an irregular shape and there are many minute scattered matters. In order to form a continuous product, one method is to expel it so as to synergistically promote the precipitation of the solute and the dispersion of the solvent by discharging in a filament form.

When an X-ray contrast agent is mixed in a liquid substance, even if it is spun into a filamentous plug, its position can be easily confirmed by X-ray.

The method of using the catheter of the present invention will be described. First, the catheter 1 has a lumen 50 for supplying a liquid substance, and an ethylene-vinyl alcohol copolymer / dimethyl sulfoxide (concentration 5 g / 100) is used as the liquid substance.
ml) and guide the catheter tip 20 into the cerebral aneurysm using a guide wire. In that state, when the ethylene-vinyl alcohol copolymer / dimethyl sulfoxide is further injected from the liquid substance introduction port 32 which is the injection port for injecting the liquid substance of the catheter base 30,
Discharge from the discharge port 52 of the catheter tip portion 20. Immediately after the ejection, the solvent dimethyl sulfoxide is dispersed in blood, so that the ethylene-vinyl alcohol copolymer is spun in a filament form. When the injection is stopped, the liquid substance is not discharged, the spinning is completed, and the yarn is interrupted. The discharge port is as small as 10 to 100 μm. Therefore, the yarn to be spun is also very thin, flexible and supple, and it forms a lump in the aneurysm, which prevents the occurrence of thrombus. Provoked and the aneurysm is occluded.

As a specific example, a tube (inner diameter 0.8 mm, outer diameter 0.
99mm), and then having a total length of 1250mm, connecting a connector (hub) to the base, and thermoforming the tip to form a nozzle having an outer diameter of 0.2mm, an inner diameter of 0.1mm, and a length of 2.5mm. An embolization catheter of the present invention was obtained.

Further, 5 g of an ethylene-vinyl alcohol copolymer (EVAL, manufactured by Kuraray Co., Ltd., EC-R101, 33 mol% of ethylene) was dissolved in 100 ml of dimethyl sulfoxide (Wako Pure Chemical Industries, Ltd., special grade reagent),
A liquid substance as a raw material for the spin embolization material was obtained. Further, a solution containing only dimethyl sulfoxide was prepared as a liquid substance protecting agent at the time of embolization. When the liquid substance is of a type in which a solute in a solvent is deposited to form an embolic material, the liquid substance protecting agent may be any agent that prevents or suppresses the dispersion of the solvent.

In order to confirm the spinning embolization state, the tip of the catheter was put in physiological saline and the inside of the catheter was primed with physiological saline. A solution of sulfoxide alone) was injected through the catheter base. Subsequently, a 1 ml syringe filled with the above liquid substance was connected to the base connector, and the syringe was manually pressurized to discharge the liquid substance from the tip of the nozzle of the catheter.

As a result, spinning is started from the tip of the nozzle, the outer diameter is 0.1 mm to 0.2 mm, and the length is 150 mm.
Of continuous filaments meandered immediately after discharge and immediately became a knitted spherical mass from the tip side. Also, pressurization is interrupted,
The spinning end could be released from the nozzle by pulling the catheter slightly. Also, because of the continuous shape,
It was not observed that the liquid substance separated / precipitated and floated as a foreign substance. The time required from the start of liquid material injection to the end was within 5 seconds.

For comparison, a catheter without the above-mentioned nozzle (made of thermoplastic polyester elastomer, inner diameter 0.8 mm, outer diameter 0.99 mm, total length 1250 mm) was used to inject the same liquid substance into saline solution. As a result of observing the formation of precipitates (embolus), multiple large and small lumps were formed. Furthermore, when pressure was applied and discharge was performed without interruption, the amount of precipitation became excessive, and the formation of many lumps was rather promoted. This was considered to be the possibility of excess emboli flowing out of the aneurysm or the outflow of a lump, leaving a potential complication of embolizing other normal blood vessels.

As another embodiment of the embolization catheter of the present invention, as in the embolization catheter 1 of the embodiment shown in FIG. 1, an embolus composed of a catheter body, a catheter tip and a catheter base (operation part). Surgical catheter 100
The tip portion of is shown in FIG. 8 as a partial sectional view.

Embolization catheter 10 shown in FIG. 8 (a).
0A consists of an outer tube 40 and an inner tube 42. The inner tube 42 is housed inside the outer tube 40, and forms a lumen 40 a in the space between the outer surface of the inner tube 42 and the inner surface of the outer tube 40.
The outer tube 40 is open at its tip, and its opening 40b communicates with the lumen 40a. The tip of the outer tube 40 has a tapered shape. The lumen 42a of the inner tube 42 is open at the tip, and the opening 42b is located closer to the base end side than the opening 40b of the outer tube 40 by a predetermined distance. Opening 42b of inner tube 42 and opening 40 of outer tube 40
The space surrounded by the inner wall of the outer tube 40 of b is defined as the lumen 40c. The tip side of the lumen 40c is narrowed in the tip direction.

A liquid substance is introduced into the lumen 40a, and a liquid substance which reacts with the liquid substance described later and solidifies is introduced into the lumen 42a. Both substances react and start to solidify in the lumen 40c. The coil 44 provided in the lumen 40c has a function of stirring both substances. By stirring and promoting mixing, the substance poured out from the opening 40b can be reliably made into a continuous solid body.

Embolization catheter 10 shown in FIG. 8 (b).
OB comprises an outer tube 40 and an inner tube 42. The inner tube 42 is housed inside the outer tube 40, and forms a lumen 40 a in the space between the outer surface of the inner tube 42 and the inner surface of the outer tube 40.
The outer tube 40 is open at its tip, and its opening 40b communicates with the lumen 40a. The tip of the outer tube 40 has a tapered shape. The lumen 42a of the inner tube 42 is closed at the tip 42c, but a plurality of openings 42b are provided around the inner tube 42. The openings 42b are not arranged side by side on the same axis, but are provided at different positions. The tip 42c of the inner pipe 42 is the outer pipe 4
It is located on the base end side by a predetermined distance from the zero opening 40b.
The space surrounded by the tip 42c of the inner tube 42 and the inner wall of the outer tube 40 of the opening 40b of the outer tube 40 is defined as a lumen 40c. The tip side of the lumen 40c is narrowed in the tip direction.

A liquid substance is introduced into the lumen 40a, and a liquid substance which reacts with the liquid substance described later and solidifies is introduced into the lumen 42a. Lumen 40c where multiple substances intersect
Reacts at and begins to solidify. Since the openings 42b are provided so that their axial positions are displaced from each other, the reaction liquid can be uniformly mixed with the liquid substance flowing in the lumen 40a. Lumen 4
The axial length of 0c can be adjusted by the reaction time of both substances.

The liquid substance used in this embodiment is composed of a combination of a reactive liquid substance and another liquid substance that cures and cures the reactive liquid substance, and is introduced to the tip portion by independent lumens. It is mixed and ejected at the tip of the needle and cured to form a yarn. As a combination of the reactive liquid substance that can be used in the present embodiment and another liquid substance that causes the reactive liquid substance to react and cure,
There are a main component and a curing agent for an epoxy-based two-component curing type resin, and a main component and a curing agent for an acrylic two-component curing type resin.

Further, at the tip of the catheter, there is provided a discharge nozzle for merging and forming two lumens for supplying a liquid substance, forming a discharge, and spinning. The length of the tip to the opening can be appropriately changed depending on the curing time of the liquid substance. Further, like the other embodiments, an opening of a lumen through which a guide wire or an observation mirror is inserted may be provided.
In that case, the catheter base (operation part) is provided with two injection ports for injecting two kinds of liquid substances and an insertion port for inserting a guide wire or an observation mirror.

Further, as shown in FIG. 6, the catheter shown in FIG. 8 may be inserted into a predetermined lumen of a catheter whose tip can be left in the aneurysm and the tip may be projected.
To describe the method of use of the present embodiment, first, the catheter portion fills one lumen supplying the liquid substance with the main ingredient which is the reactive liquid substance, and the other lumen for reacting and curing the reactive liquid substance. The curing agent, which is a liquid substance, is filled, and the inside of the discharge port is filled with physiological saline so that the two types of liquid substances are not mixed before the protrusion. In this state, a guide wire is used to guide the catheter tip into the cerebral aneurysm. When the liquid substance is injected evenly from the injection port for injecting the liquid substance in the catheter base (operation part), two kinds of reactive substances move to the discharge port, and the physiological saline is discharged into the blood, and then the discharge port. Are mixed, and while being cured, they are continuously discharged one after another in the form of filaments. When the injection is stopped, the supply of the reactant is stopped, so that the spinning is finished and the yarn is interrupted. It is desirable to grasp the volume of the aneurysm in advance and then calculate the injection volume of both substances to inject.

The discharge port is as small as 50 to 200 μm. Therefore, the yarn to be spun is also very thin, flexible and supple, and forms a lump in the aneurysm, causing thrombus. And the aneurysm is occluded.

As another embodiment, the embolization catheter shown in FIG. 9 will be described. It should be noted that the same reference numerals are given to the same configurations as those of the embodiments described in FIG. 1 and FIG. Figure 9
The embolization catheter 100C shown in (a) comprises a catheter body 10, a catheter tip 20, and a catheter base (operation part) 30. The base 30 comprises a hub 36 which is composed of a liquid substance introduction port 32, a guide wire port 34 and a light source connection port 38 for sending light to an optical fiber.

The boundary between the body 10 and the tip 20 is shown in FIG.
Because of the configuration shown in FIG. 3, the main body portion 10 has high rigidity and excellent pushability, and the tip portion 20 is flexible and has good blood vessel followability. Catheter tip 20 of the embodiment as shown in FIG. 9 (b), the discharge nozzle 54 of the optical fiber tip 16 for irradiating light to the discharge port 5 2 and discharge port for discharging the liquid material is provided, Light is irradiated just before the liquid substance is discharged. The tip of the optical fiber is cut at an acute angle, and the cut surface 14 is a mirror. The light passing through the optical fiber is reflected, the optical path is changed, and the discharge port of the lumen 50 of the liquid substance immediately next to it is reflected. It is designed to illuminate the inside of 52. The distal end side of the discharge nozzle 54 of the catheter 100C is not thinned. The shape of the discharge nozzle is not restricted as long as it can be cured by irradiation of light and can maintain continuity without being broken. If the tip is reduced in diameter, which favors the production of more filamentous material, then reduction in diameter may be selected.

Further, similarly to the other embodiments, the opening 62 of the lumen 60 through which the guide wire or the observation mirror is inserted.
Is also provided.

The thickness of the optical fiber is preferably thick because it affects the amount of light at the tip, but if it is too thick, the flexibility of the catheter itself will be lost, so when the diameter of the catheter is 0.5 to 1 mm, Approximately 50 to 400μ
Those having a diameter of m are preferable. Also, a plurality of ultrafine optical fibers may be combined, and the total cross-sectional area thereof is preferably equal to that of the above-mentioned fibers.

The liquid substance used in this example is a photoreactive liquid substance which is cured by irradiation with light. Specifically, polyester acrylate, urethane acrylate, acrylic acid ester, methacrylic acid ester and the like are used. In addition to the acryl-based photo-curable resin, a photo-radical addition type or photo-cationic polymerization type photosensitive resin can be used.

The catheter base (operation part) 30 is provided with a light source (not shown) which is connected to the rear end of the optical fiber and supplies light. Further, a liquid substance introduction port 32 and a guide wire port 34 are provided.

The wavelength of the light source can be appropriately changed depending on the liquid substance. Specifically, for polyester acrylate and urethane acrylate, a light source having a wavelength of 300 to 500 nm is applied. The photo-curable resin may be an acrylic photo-curable resin having an acrylic acid ester, a methacrylic acid ester or the like, or a photo-radical addition type or photo-cationic polymerization type photosensitive resin.

The method of use of this embodiment will be described. First, the lumen 50 for supplying the liquid substance of the catheter 100C is filled with the photoreactive liquid substance.
The guide wire is used to guide the catheter tip 20 into the cerebral aneurysm. When the liquid substance is evenly injected from the liquid substance introduction port 32 for injecting the liquid substance of the catheter base (operation part) 30, the discharge starts from the discharge port 52. When the light source is turned on at the same time as ejection, the liquid substance is irradiated with light,
Curing begins, and the cured substance is discharged in a string of threads. When cutting the thread, turn off the light source, and then stop the injection.

An embodiment having the configuration shown in FIG. 10 for the tip portion 20 of the embodiment shown in FIG. 9 will be described. In FIG. 10, the catheter tip portion 20 is provided with a discharge nozzle 54 including a discharge port 52 for discharging a liquid substance and an optical fiber tip portion 16 for irradiating the discharge port with light, and the liquid substance introduced from the lumen 50 is Light is emitted just before the ejection. The tip of the optical fiber is located at the coaxial center of the discharge port, and the photoreactive substance is discharged while wrapping the tip of the optical fiber, and light is emitted from the inside. There is also an advantage that it can be used as a light source for an endoscope. The optical fiber is composed of a core and a clad in the peripheral portion having a refractive index smaller than that of the core, and is designed to confine the light in the fiber. The optical fiber at the catheter tip portion 20 is not provided with a clad at the optical fiber on the tip side of the point 17 with the point 17 protruding into the liquid substance introduction lumen 50 as a boundary. Therefore, in the discharge nozzle 54, it is possible to adjust the length of a portion without a clad even for a liquid substance which is not instantaneously irradiated with light from an optical fiber without a clad in the circumferential direction to react and cure. The range of choices for liquid substances is expanded.

Further, similarly to the other embodiments, the opening 62 of the lumen 60 through which the guide wire or the observation mirror is inserted.
Is also provided.

Although two examples are disclosed here, the light transmitted through the optical fiber may be irradiated to the photoreactive liquid material immediately before the projection, and the shape thereof is not particularly limited.

Next, another embodiment of the present invention will be described with reference to FIGS. 11, 12 and 13. FIG. 11 is a schematic diagram in which the catheter 100D of this example is placed in a cerebral artery. The catheter 100D includes a catheter body 10, a catheter tip 20, and a catheter base 30.

The catheter body 10 will be described with reference to FIG. 12, which is a sectional view thereof. The catheter body 10 supplies light to a micro pump 400 (see FIG. 13) described later, an inner hole 310 for supplying a spinning liquid substance, an insertion hole 320 for inserting a guide wire or an observation mirror, and a photoelectric conversion device 450 described later. A plurality of optical fibers 330 are provided.

FIG. 13 shows the catheter tip portion 20 in use. The catheter tip 20 is joined to the catheter body by a joint 420 made of a shape memory alloy. In this shape memory joint, two shape memory alloy wires 430 and 430 are opposed to each other with respect to the inner lumen, and the microheater arrays 440 and 44 are respectively provided thereto.
0 is attached to each of the micro-heater arrays 440 and 440.
When the photoelectric converter is irradiated with light through the optical fiber 330, the photoelectric converter generates electricity, and the electric power heats the micro heater arrays 440 and 440 to change the shape memory alloy into a predetermined shape. The direction of the catheter tip portion 20 can be delicately changed by utilizing. Here, the shape memory alloy wire 430 is arranged in a loop shape in the inner cavity and electrically heated through the micro heater array.

The tip portion 46 of the catheter tip portion 20 is also included.
0 is a micro pump 400, and this pump 400
A photoelectric conversion device 470 that serves as a power source for driving the motor, a spinning micro nozzle 480 connected to a micro pump, and an insertion hole opening 490 are provided.

An optical fiber (not shown) communicated from the catheter base through the catheter body 10 is connected to the photoelectric conversion device 470, and light sent from the catheter base through the optical fiber is converted into a photoelectric conversion device 47.
The voltage is converted into a voltage by 0, and the micro pump 400 is driven by this converted voltage.

The micropump 400 is a diaphragm-type micropump, which applies a pressure by the micropump 400 further at the tip before supplying it to the spinning micronozzle 480 to give a shear stress to the liquid substance to be discharged. is there.

As the liquid substance used in this example, fibroin or the like that can be spun when shear stress is applied, or the solute precipitation type as described above can be used.

The insertion hole opening 490 is the opening of a guide wire or observation mirror insertion hole that communicates with the catheter base, and the tip of the guide wire is pulled out from this opening to select a blood vessel, or a blood vessel and an affected area are observed with an observation mirror. It can be performed.

A grip portion 600 formed in a shape that is easy to operate on the catheter base 30, an injection portion 610 for a liquid spinning material, a discharge operation switch 620, and an operation ball for controlling the articulating bending direction of a multi-joint shape memory alloy. 630 and the like are arranged. In addition, the base is a light source device for endoscopes and discharge devices,
And a monitor unit 6 including a screen display device for images of the endoscope
40 to the cable 40 by a cable 650.

Embolization catheter 10 having the above structure
The following is a typical procedure for actually using the action of 0D.

1. The catheter tip part 20 is guided by a guide wire and placed in the cerebral aneurysm 500. Selection of a branch that is difficult to guide with a guide wire or delicate guidance to the inside of the aneurysm 500 converts light from the optical fiber 330 into a current through a photoelectric converter, and the micro heater array 440 heats the shape memory alloy wire 430. Can be changed to a predetermined shape, and the direction of the tip portion 20 is changed slightly.

2. When reaching the inside 500 of the cerebral aneurysm, the spinning solution is supplied to the micropump 400 from the spinning solution supply lumen 310.

3. The micro pump 400 is driven by the photoelectric conversion device 470 to increase the chamber internal pressure. Then, the spinning solution (solution of fibroin) is applied to the micro nozzle 48.
The embolus 295 is spun by high-pressure discharge from 0.

4. The discharge-molded filamentous embolus 295 is continuous, so there is no danger of finely flowing out to the outside of the aneurysm 501. Further, there is no danger of crushing the bump wall 503 by squeezing it strongly.

5. Furthermore, while the thread material having a high affinity or reactivity with the aneurysmal intimal membrane 502 is well fixed to the aneurysm wall 503, the thread-shaped filamentous embolus 295 reacts with blood to form a coagulated aneurysm. Completely close the inside 500.

6. The embolus 295 ends when the spinning solution discharge is stopped, and an observation mirror is inserted through the insertion hole 320 such as the guide wire to confirm it.

The observation mirror is useful for confirming the position of the tip of the catheter before spinning and the condition during spinning. Obviously, it can be used in addition to the above procedure.

The filamentous embolus formed from the embolization catheter of the present invention described above is 0.01 to 1.0.
Those having a thickness of mm are preferable, and the thickness is 0.1 to 0.5 mm.
It is more preferable that the thickness is If the diameter is continuous within the handling range, the change in outer diameter is not affected by embolization. A filamentous embolus that has been crimped by being discharged from a catheter is preferable because it tends to be a bead shape and can be filled from the inside of the aneurysm. Further, as the thread, a thickness of 1 to 100 denier, more preferably 10 to 50 denier is preferable.

[0089]

As described in detail above, according to the present invention, the embolization catheter is provided at the distal end thereof with a spinning means for forming a liquid substance for spinning as a thread-like embolic material. It is possible to use an object, eliminate the drawbacks such as embolic substances flowing out of the aneurysm and damage the fragile aneurysm wall due to the embolic substance, and it is possible to treat aneurysms safely and reliably effective.

Since the discharge-molded thread-like embolic substance is continuous, there is no danger of being finely dispersed and flowing out of the aneurysm.

Further, since it becomes a lump of thread-like embolic substance, there is no danger that the wall of the aneurysm will be strongly pressed and ruptured after indwelling unlike conventional balloons, metal coils, and polymers such as EVA. Furthermore, the packing density is high, and the pressure inside the aneurysm can be reduced immediately after placement. Also, by using a filamentous embolic substance that has a high affinity or reactivity with the aneurysm membrane, it adheres well to the aneurysm wall, and the beaded embolus substance reacts with blood to form an aneurysm as a clot. Complete occlusion is possible.

Further, by having at least one other passage separated from the passage for introducing the liquid substance, it can be used as an insertion passage for a guide wire or an endoscope, and the catheter can be introduced into the treatment site quickly. Also, the embolic material can be spun while observing with an endoscope.

By providing the spinning means with a discharging means, the direction of spinning is constant, and the spun yarn is spouted according to the direction of the distal end of the catheter, so that the yarn is spun at various places in the cerebral aneurysm. Can be blown out, and a uniform ball-shaped mass can be formed.

Further, a liquid substance is formed from a reactive liquid substance and another liquid substance which causes the reactive liquid substance to react and harden, and is introduced to the tip through passages for introducing independent liquid substances, and the spinning means reacts. By forming a filamentous embolic substance by mixing the mold type liquid substance with another liquid substance that reacts and cures the reactive type liquid substance, it is easy to introduce into the liquid substance up to the tip part, and the liquid substance can be easily handled. Become. Further, the liquid substance is a photoreactive liquid substance that is cured by light irradiation, and the spinning means has a light irradiation means for reacting and curing the photoreactive substance, so that the liquid state can be maintained until immediately before spinning, and the spinning is completed. The spinning can be easily completed only by blocking the subsequent light.

Furthermore, since the liquid substance forms a thread-like embolic substance by shear stress, and the spinning means has a shear stress applying mechanism for applying shear stress to the liquid substance,
The liquid state can be maintained until just before spinning, and spinning can be easily stopped only by stopping the application of shear stress.

The thickness of the spun yarn is 1 to 1
By setting the denier to 00, there is flexibility, and it becomes possible to easily form a ball-shaped mass, and a coagulated mass easily occurs, so that the cerebral aneurysm is surely blocked. Become.

[Brief description of drawings]

FIG. 1 is an overall view and a sectional view of an embolization catheter of the present invention.

FIG. 2 is a cross-sectional view of the embolization catheter of the present invention.

FIG. 3 is a perspective view of the distal end portion of the embolization catheter of the present invention.

FIG. 4 is a distal end perspective view of the embolization catheter of the present invention.

FIG. 5 is a perspective view and a cross-sectional view of the distal end portion of the embolization catheter of the present invention.

FIG. 6 is a distal end perspective view of the embolization catheter of the present invention.

FIG. 7 is a sectional view of the distal end portion of the embolization catheter of the present invention.

FIG. 8 is a cross-sectional view of the distal end portion of the embolization catheter of the present invention.

FIG. 9 is an overall view and a perspective view of a distal end portion of the embolization catheter of the present invention.

FIG. 10 is a perspective view of the distal end portion of the embolization catheter of the present invention.

FIG. 11 is a schematic view showing a state in which the embolization catheter of the present invention is inserted into a human body.

FIG. 12 is a cross-sectional view of the embolization catheter body of the present invention.

FIG. 13 is a perspective view of a catheter tip portion of the present invention.
20: Catheter tip 54: Discharge nozzle (spinning means) 52: Discharge port 62: Opening

Claims (1)

[Claims] 1. A catheter for embolization, which comprises a catheter having a passage for introducing a liquid substance, and having a spinning means at a tip end portion for forming the liquid substance as a thread-like embolic material.