JPS6030225B2 - Inductor with an indwelling member at the tip - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a removable inductor having an indwelling member at its distal end, and particularly relates to a removable valve used for treatment of arterial cancer, arteriovenous malformation, arteriovenous obstruction, buccal occlusion, etc. Regarding catheters.

Catheters have traditionally been used as essential medical instruments in both diagnosis and treatment.

Recently, so-called balloon catheters, in which a balloon that can be inflated and deflated is fixed to the tip of the catheter, have been introduced into the bloodstream to reach inside minute blood vessels that could not be reached with conventional catheters without balloons. ``The range of use of catheters is expanding even further now that catheters can be inserted.If it becomes possible to remove the inflation balloon from the tip of the catheter at the desired site, it will be possible to perform various tasks that were not possible with conventional methods.'' It becomes possible to treat vascular disorders.

An example of this is its application to the treatment of typical vascular disorders such as arterial cancer, arteriovenous malformation, and arteriovenous ischemia. For example, by placing an inflatable balloon in the arteriosus, serious sequelae can be prevented in the event that arterial cancer ruptures, and by occluding the blood vessels that flow into arteriostatic malformations with the dislodged balloon. "Similarly, it is possible to prevent the sequelae associated with bleeding due to arteriovenous malformation. Furthermore, if the arteriovenous malformation can be occluded, blood flow in the arteries can be restored to a state close to normal. These are the few examples listed here. As is clear from the above, if a detachable balloon catheter were developed, the good news would be for patients suffering from cerebrovascular disorders and cardiovascular disorders, which are the first and third leading causes of death in Japan. There are things that cannot be measured.

This new treatment does not require any surgical procedures;
When considering that it can be completed with just an injection, so to speak,
Furthermore, it is clear that its development is highly significant. The site from which the balloon is to be removed is primarily a vascular disorder located deep within the body.

Therefore, first of all, it is necessary to ensure safety that the balloon will not detach from the catheter before it reaches this site, and to ensure that the balloon can be detached even in such a deep place. If the balloon's rubber elasticity is used to tightly secure the balloon to the catheter, it may be relatively easy to remove the balloon, but there is a possibility that the balloon may separate before reaching the target site. is high.

Furthermore, when a double catheter is used and the balloon attached to the tip of the inner catheter is removed by pulling out the inner catheter while fixing the outer catheter, the catheter device becomes larger due to its structure, and Due to the inability to use flexible materials, they can hardly be used for occlusion of microvessels. Therefore, we decided to overcome these drawbacks by inventing a slotted balloon catheter, and have already applied for a patent on April 6, 1954. Pseudo-slit balloon catheters are extremely effective for occluding blood vessels in the brain, and are being used to treat many patients. However, since the material of the catheter body needs to have higher resistance to damage than the material of the joint where it is to be cut, a certain degree of hardness is required. Therefore, extremely flexible materials (such as silicon) cannot be used. For this reason, for example, in cerebral blood vessels, it is effective for occluding approximately the anterior part of the corpus callosum of the anterior cerebral artery, the middle cerebral artery, and the M3 part, but it is difficult to use for occluding peripheral blood vessels. In addition, the force of damage is well transmitted when the catheter is short, but when the catheter is long, for example when occluding a vascular defect in the basilar artery via the femoral artery, it is difficult to transmit the rubbing force effectively. In this case, the material must be made harder up to the middle of the catheter. Therefore, in order to occlude more peripheral blood vessels, we investigated various catheters that allow the use of extremely flexible catheters and that have a joint that allows the balloon to be detached without applying any external force to the catheter. We have arrived at the present invention.

That is, the present invention provides, in an inductor having an indwelling member at the tip thereof, a portion to be fused at or near the joining portion of the indwelling member and the inductor body, and a port cut at the point. An inductor having an in-vivo indwelling member characterized by being provided with a heating means for heating, and in particular, in a catheter having a balloon at the tip, a melting point at or near the junction between the balloon and the catheter body,
For example, it is a removable balloon catheter characterized by being provided with a member to be melted and a heating means for melting the part.

The removable balloon catheter of the present invention can be removable no matter what material the catheter is made of or no matter how long it is, and the balloon and catheter body are fused and cut after reaching the target site. There is absolutely no risk that it will dislodge before reaching the target area.

Examples of the structure of the removable balloon catheter of the present invention include those shown in FIGS. 1 to 9, and those shown in FIGS. 1 and 3 are particularly preferred.

First, FIG. 1 will be explained. The fusing material 2 connected to the balloon 3 is solid at body temperature, does not easily rupture due to external force, and easily dissolves in blood vessels at a temperature above body temperature that does not evaporate water (100 oo). Furthermore, it is better if it is not harmful to living organisms even if it dissolves in the blood, and it is even better if it is flexible and easy to process.

As the material for the part 2 having such properties, hydrophilic polymers are preferred, and polyvinyl alcohol polymers are particularly preferred. Here, the polyvinyl alcohol polymer means a homopolymer of vinyl alcohol, a copolymer of vinyl alcohol and another monomer copolymerizable with vinyl alcohol (eg, ethylene, etc.), or a derivative thereof. The shape of the member 2 is a tube or a hollow fiber, and its outer diameter, wall thickness, and length depend on the size and shape of the blood vessel to be occluded and cannot be unambiguously defined. Buddha, preferably 200-70
0 threads, wall thickness 10-400 threads, preferably 10-200 threads
The length (from the end of the balloon 3 to the end of the main catheter 1) is 2 to 50 ribs, preferably 5 to 3 ribs. A heating means is provided outside the section 2.

As a heating means, for example, dipole electrodes 12 and 13 with bare conductive wires may be wound around the outside of the member 2. Electrode 1
2 and 13 can be provided inside the member 2 or can be embedded in the member 2. Each electrode 12, 13
The high frequency current generator 18 is connected by the lead wires 14 and 15.
is familiar with The high frequency current passes through the member 2 to the electrode 12,
The member 2 is melted by flowing between the holes 13 and 13. It is preferable that the distance between the electrodes 12 and 13 be as close as possible because the member 2 can be fused more accurately in a shorter time. The lead wires 14 and 15 are preferably wires that have good conductivity, are free from leakage, generate minimal heat, are soft and can be processed into extremely thin pieces, such as enamel-baked copper wires. Lead wire 14
, 15 are connected from the outside of the tube 17 to a high-frequency current generator 18' through an adhesive portion 16 between the tube 17 and the catheter body 1 provided at the end of the balloon catheter. As a heating means, it is preferable to use a very soft catheter body, and when using a catheter body, one using high frequency current as shown in Fig. 1 is preferable;
If the flexibility of the fiber that allows the laser to pass through is sufficient, a laser may be used. The member 2, balloon 3, and catheter body 1 are bonded using adhesives 4, 5, such as cyanoacrylate or epoxy adhesives.

In this case, as shown in FIG. 1, it is preferable that the balloon 3 and the member 2, and the member 2 and the main body catheter have smooth surfaces using adhesives 4 and 5. In particular, if the member 2 and the catheter body 1 are made smooth with the adhesive 4,
When this balloon catheter is inserted into a blood vessel, it does not damage the blood vessel. In FIG. 3, electrodes 19 and 20 made of conductive metal foil are placed above and below the member 2 as heating means, and one end of the metal foils 19 and 20 is attached to the member 2 with an adhesive 4.
It was installed on.

Figure 5 shows a monopole electrode 2 with a conductive wire exposed as a heating means.
A conductive wire 22 leads to the high frequency current device 18, and one conductive wire 29 leads from the patient's body surface 30 to the high frequency current device 18'.

This is not necessary if there is no risk of the member 2 bending, but if the member 2 is soft and there is a risk of bending, cover the distal end of the catheter body 1 with the member 2 as shown in Figure 8. In addition, it is preferable to fix the cover 8 with a bush adhesive 9 to prevent the member 2 from bending when inserted into the blood vessel.

The cover 8 is preferably a cylindrical member that does not bend. The sheet 11 is provided to further prevent the balloon 3 from bending and to facilitate blood vessel insertion, and is fixed to the strand member 2 and the balloon 3 with an adhesive 5,1. That is, in FIG. 8, by providing the cover 8 and the sheet 11, the tip of the cover 8 and the end of the balloon 3 come into contact with each other with some gap, so the balloon 3 is prevented from bending. Further, since the upper surface of the cover 8 and the upper surface of the balloon 3 are smooth, insertion into the blood vessel is easy and the blood vessel wall is not damaged. In addition, as another embodiment when there is a possibility that the member 2 may bend, as shown in FIG. In this case, the core material 6 may be removed just before the balloon is removed.

In addition, as another embodiment when there is a possibility that the member 2 may be bent at the insertion part of the eraser needle, a hydrophilic polymer, especially a water bathing polymer such as polyvinyl alcohol, starch, or dextran, is coated on the outer periphery of the member 2. There is a way to keep it.

In this case, the water-soluble polymer to be applied must be one that cannot be dissolved in blood. The catheter body 1 needs to have a tensile strength that will not cause damage when inserted into a blood vessel.

Furthermore, in order to be able to easily insert the tube into even curved microvessels, a thin tube having a Young's modulus of 1 to 100 kg when wet (in water of 2500, preferably 2 to 20 k9) is suitable. In addition to the material of the member 2 described above, the material of the catheter body 1 includes silicone, polyethylene, polypropylene, nylon, polyurethane, thermoplastic polyester (polybutylene terephthalate, etc.), silicone-polyurethane combination, tympanic PVC, ethylene- Examples include pinyl acetate copolymer, but silicone is particularly preferred. The balloon 3 used in the present invention may be of any material as long as it has the necessary elasticity and is resistant to disinfection, and the material is preferably rubber (natural rubber, synthetic rubber), European segmented polyurethane, or the like.

Its shape and size are determined by the type of target blood vessel, but it is usually a cylindrical cap-like type as shown in the drawing, making it especially easy to insert into curved blood vessels. For this reason, the wall thickness of the balloon when not swollen should be as thin as possible, for example, 500 mm or less, preferably 200 mm or less. Balloon removal from the balloon catheter of the present invention generally occurs in the following order. That is, a removable balloon catheter is introduced into a blood vessel, and the inflated balloon is placed on the bloodstream to allow the balloon catheter to reach the target blood vessel site. next,
The inside of the balloon is replaced with as much polymerized hardening liquid as possible, and the balloon is further inflated so that it comes into close contact with the blood vessel wall. If a core material such as nylon thread has been inserted in advance, remove it from the catheter. Thereafter, the member 2 is melted by applying electricity. If it is necessary to confirm that the fusion has occurred, for example, as shown in FIG. It is also possible to keep it firmly attached.When it melts, the distance between the two metal pieces changes, so the organic substance can be seen by X-ray photography.As described above, the removable balloon catheter of the present invention is extremely simple. Because of its structure, it is easy to manufacture, the manufacturing cost is low, and it is safe because the balloon and the catheter body will not separate unless the tube 2 is heated to a temperature higher than body temperature.

Further, since the member 2 can be melted accurately, the balloon can be removed without being displaced from the target area and without damaging the blood vessel wall. Examples of the inductor having the indwelling member of the present invention include, in addition to the removable balloon catheter described above, an inductor having an indwelling member at its tip filled with a drug, such as an anticancer agent.

An inductor with a tip filled with such drugs, such as anticancer drugs, is inserted into the target site (affected area, cancerous area) within the body.
After the inductor body is injected, the inductor body is removed from the body by fusing the member and the inductor body, leaving the drug-filled material at the tip at the target site. By doing so, the drug is gradually released to the affected area or cancerous area, allowing local administration to be concentrated in the affected area or cancerous area, suppressing side effects caused by systemic drug administration, and enabling efficient treatment. The present invention will be further explained below with reference to Examples, but the present invention is not limited to these Examples.

Example 1 As shown in Fig. 1, a natural rubber balloon 3 (outer diameter 800 mm when deflated, wall thickness 100 mm) is attached to a polyvinyl alcohol tube 2 (outer diameter 500 mm, wall thickness 100 mm), and both were adhered with a cyanoacrylate adhesive, and the joint was coated with epoxy resin 5 to make a smooth surface.

Next, 0.05 for silicone chew 1 (gaiyo 600 Buddha)
Two side enamelled wires 14 and 15 were passed through. The enameled wire is brought out from one end, and among the parts of the balloon 3 and polyvinyl alcohol tube 2 prepared earlier, the polyvinyl alcohol tube 2 is inserted into the silicone tube 1' and glued with a cyanoacrylate adhesive, and then the joint is bonded. The part was coated with epoxy resin 4 to give a smooth surface.
One enameled wire taken out to the outside was brought to the end of the polyvinyl alcohol tube, a portion of the enamel was peeled off, and the wire was loosely wrapped in a ring to form an electrode 12. The other electrode 13, from which part of the enamel had been removed, was similarly wrapped around the central side of the polyvinyl alcohol tube. The distance between the electrodes 12 and the hook 3 were made as short as possible, about 1.3 mm.
On the other hand, take out the two enameled wires coming out of the silicone tube 1 at the other end, and insert a chromium-treated polyethylene tube (outer diameter 600#, wall thickness 180mm) into one end of the wire. Glue with cyanoacrylate adhesive and seal the joint with epoxy resin 1.
6 to make a smooth surface. After confirming that the lead wire outlet is completely sealed, use a tester to check whether there is a short circuit between the lead wires 2 and 13 and ``lead wire 47 tatami 5'' and whether the lead wires are broken. Ta. After immersing this balloon catheter in physiological saline, the enamel coating of the lead wire coming out from the polyethylene tube 17 was peeled off, and the high-frequency current generator 18 manufactured by AESCLUP was removed.
connected to. After injecting a curable liquid (2-hydroxyethyl methacrylate and a polymerization initiator) into the balloon and curing the balloon, the output of the high-frequency current generator (D
When I set the osis) to 3 and turned on the power, it was about 1. With a trowel, the joint 2 made of a polyvinyl alcohol tube was dissolved, and the balloon 3 was separated from the catheter body 1 made of a silicone tube. Example 2 After an adult dog was completely anaesthetized, the external jugular vein and carotid artery were anastomosed to create an artificial artery and vein.

Fr (French unit) 5 in the carotid artery on the heart side from Watanabe
．． A No. 5 sheath introducer was inserted. A balloon catheter prepared in the same manner as in Example 1 was inserted through this introducer. On the other hand, the lead inside the balloon catheter. I carefully checked the wires and electrodes with a tester to make sure there were no short circuits. Since the silicone catheter is very soft and cannot be injected without preventing the backflow of blood from the sheath, it was housed in a syringe 23 as shown in FIG. 10 and injected. That is, the balloon catheter was built into the syringe 23, and together with the physiological saline 24 in the syringe 23, it was injected into the blood vessel. In FIG. 10, 16 is a sucker, 25 is a tip of the rubber sucker, and 27 is an outlet of the syringe. Further, 26 is a metal tube, which is installed to penetrate the sucker tip 25, and a silicone tube is passed through the metal tube 26, and the gap therebetween is sealed with resin. Also 28 is lc
C syringe, used to introduce contrast media, etc. Next, the balloon was inflated with a contrast agent (metrizamide) and guided to Watanabe. After removing as much of the contrast medium as possible, a curable liquid capable of contrast imaging (2-hydroxyethyl methacrylate and a polymerization initiator) was injected, the balloon was inflated, and the watabe was occluded. After the liquid hardens, connect the lead wire to A.
When connected to a high frequency current generator manufactured by ESCLUP and energized for 1 second at an output (Dosis) of 3, the balloon and catheter were separated. It was also confirmed that only the Kanbu area was occluded and the four carotid arteries were preserved. The dogs used in the experiment recovered well from anesthesia, and no effects of the manipulation were observed.

Example 3 After complete anesthesia of an adult dog, an arterial cancer was artificially created in the carotid artery using an external jugular vein graft.

The balloon was guided into the arterial cancer in the same manner as in Example 2.
The curable liquid used in Example 2 was injected into the balloon, and after the liquid had hardened, electricity was similarly applied at an output (Dosis) of 3, and the balloon was separated in 1 second. Only the arterial cancer was occluded with the balloon, confirming that there was no stenosis in the carotid artery. There were no effects on the experimental dogs. Example 4 A carotid artery and external jugular vein were artificially created in an adult dog.

A Fr6.0 polyethylene catheter was inserted from the right femoral artery, and the catheter was guided to the right jugular vein using the Seldinger method. This catheter was passed through, and a balloon catheter prepared in the same manner as in Example 1 was housed in a syringe as in Examples 2 and 3, and the syringe shown in FIG. 10 was inserted into the carotid artery. After guiding the balloon to the recess in the same manner, the curable liquid used in Example 2 was injected, and the rock was closed with the balloon. Again, the high frequency current output (Dosis) was 3, and the balloon was released after 1 second of energization. Adult dogs were not affected.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of the balloon catheter of the present invention, and FIG.
The figures are a cross-sectional view taken along the line A-A' in FIG. 1, FIG. 3 is a partial vertical cross-sectional view of a balloon catheter according to another embodiment of the present invention, and FIG. 4 is a cross-sectional view taken along the line B-B' in FIG. , FIG. 5 is a longitudinal sectional view of a balloon catheter according to another embodiment of the present invention, FIG. 6 is a cross-sectional view taken along line C-0 in FIG. 5, and FIGS. FIG. 1 is a partial longitudinal cross-sectional view of the example balloon catheter, and FIG. 10 is a longitudinal cross-sectional view of a syringe for inserting the balloon catheter of the present invention into a blood vessel. Diagram 7: Diamond 2: Diamond 3: Koto: 4: Hair diagram: Burial diagram: 7: Figure 8: Hair? Illustration.

Claims (1)

[Scope of Claims] 1. In an inductor having an indwelling member at the tip thereof, a part to be fused at or near the joint between the indwelling member and the inductor body, and a method for fusing the part at the part. An inductor having an indwelling member at its tip, characterized in that it is provided with a heating means. 2. An inductor having an indwelling member at the distal end of claim 1, wherein the part to be fused is made of a member that is fused. 3. An inductor having an indwelling member at its tip as claimed in claim 1 or 2, wherein the part to be fused is made of a member made of polyvinyl alcohol. 4. An inductor having an indwelling member at its tip as set forth in claim 1, 2, or 3, wherein the heating means is a heating means using high-frequency current. 5. An inductor having an in-vivo indwelling member at its tip according to claim 1, 2, 3, or 4, wherein the in-vivo indwelling member is a balloon and the inductor main body is a catheter.