JPH0324191Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] This invention relates to medical catheters, and more specifically, when used as a balloon catheter, a balloon can be easily attached to the tip of the catheter body, and the balloon This invention relates to a highly safe catheter that does not come off during use.

[Conventional technology]

Conventionally, various balloon catheters have been known for use in urinary catheterization, cardiac catheterization, intraventricular catheterization, and the like. For example, US Pat. No. 3,435,826 and US Pat. No. 3,467,101 disclose two types of embolus removal catheters used to remove blood clots from blood vessels.

Such a catheter is used by first inserting the catheter into a blood vessel through an incision, moving a deflated balloon to a position deep inside the thrombus, then inflating the balloon deep inside the thrombus and removing the catheter. At this time, the balloon attached to the tip of the catheter body acts as a resistor to push the blood clot in front of it until it reaches an incision from which it can be easily removed.

Therefore, the use of this type of balloon catheter carries certain risks, for example, if the balloon or other parts of the catheter come apart during use, part of the catheter may be lost into the blood vessel, thereby causing This poses a risk of occlusion of the vascular system.

By the way, in the conventional manufacturing method of these balloon catheters, an inflation balloon portion is separately manufactured in advance, and this is wrapped so as to surround one circumferential surface of the catheter body. Next, it is known to adhere and fix the balloon to the catheter by applying adhesive to both ends of the balloon or tying both ends of the balloon with thread, and then coating the catheter with rubber latex or the like from the outside. . Another known method is to attach a prefabricated balloon to the catheter body, then apply adhesive to the entire catheter, and then cover the outside with rubber latex to increase the adhesion between the inner and outer rubber layers. It is being

However, in the balloon catheter made by the conventional method as described above, after the initially formed inner rubber layer has almost solidified, when the balloon section is inflated in order to further coat the outer side with rubber latex, Starting from both ends of the balloon, delamination tends to occur between the inner rubber layer formed first and the outer rubber layer formed later, which may cause the balloon to lose its inflated shape and not to fulfill its role as a balloon. , and other pre-manufactured balloons are interposed between the inner rubber layer and outer rubber layer of the catheter, so even when the balloon is not inflated, the balloon protrudes compared to other parts, which hinders catheter introduction. There have been various drawbacks, such as the possibility that the balloon may be dangerous, and the process for fixing the pre-manufactured balloon to the catheter body is relatively complicated, resulting in poor work efficiency.

Therefore, in order to facilitate the manufacturing process and eliminate the delamination problems associated with latex catheters,
Recently, the catheter body is molded from a thermoplastic resin that can be melt extruded, the balloon is molded from an elastic material such as silicone rubber so that it can be stretched inside the body, and these are joined using bonding methods such as adhesives. An integrated system is being developed.

[Problem that the invention attempts to solve]

However, since these are made of different materials, it is difficult to obtain sufficient adhesive strength between the two using known bonding techniques such as adhesion or heat fusion, and it is difficult to obtain sufficient adhesive strength between the two by tying the balloon with string. If the catheter is secured using a catheter, there is a risk that the balloon or thread may become detached from the catheter during use. moreover,
In the conventional catheter described above, even when the balloon is not inflated, the outer diameter of the catheter at the part where the neck of the balloon is inserted is thicker than other parts, which may impede the introduction into the body. In terms of process, work efficiency, etc., it could not be said that the results were necessarily satisfactory.

This invention was made to solve these problems; the balloon is extremely easy to install, can be smoothly inserted into the body during use, and the balloon can be detached from the main body during use. The purpose is to provide a catheter with excellent safety that does not cause any damage.

[Means for solving problems]

This invention was made in order to solve the problems of the prior art described above, and therefore, according to this invention, a diameter of about 50% of the outer diameter of the catheter is attached to the tip of the catheter body made of a polymeric material. A catheter is constituted by integrally forming a small diameter part and a protrusion part for locking a balloon on the outer peripheral surface of the small diameter part.

In this configuration, the protrusion can be provided at the end or the middle of the narrow diameter part, and when used as a balloon catheter, the neck of the balloon is locked to this protrusion, thereby preventing the balloon from detaching. Furthermore, if the narrow diameter part is formed so that it is provided at the tip of the catheter body via the tapered part, the tip of the catheter will not get caught on the wall surface when introduced into the body, allowing smooth insertion. Become.

[Effect]

According to this invention, as described above, the tip of the catheter body has a narrow diameter part that is approximately 50% smaller than the outer diameter of the catheter body, and a protrusion for locking the balloon on the outer peripheral surface of this narrow diameter part. When used as a balloon catheter, the balloon, which is made of an elastic material such as silicone rubber and has an opening neck smaller than the narrow diameter section at the tip of the catheter body, can be used as a balloon catheter. When the balloon is inserted from the distal end of the opening to the point where it passes over the protrusion while expanding the inner diameter of the opening neck, in addition to its own elastic contraction force in the radial direction, the balloon is also held by the protrusion, and the narrow diameter of the catheter body The balloon is tightly fixed to the catheter body, so the balloon does not come off from the catheter body during use, without having to glue, fuse, or use thread to fix the balloon to the catheter body, as in the case of conventional methods. Work is greatly simplified,
Balloon catheters can be obtained at low cost.

Furthermore, since adhesives, threads, etc. are not used, there will be no elution of harmful substances into the body or occlusion of blood vessels due to detachment of the threads, resulting in excellent safety.

Furthermore, if the narrow diameter part is provided at the tip of the catheter body via a tapered part and the protruding part is formed smaller than the outer diameter of the catheter body, it will be advantageous in terms of insertion into the body.

〔Example〕

FIG. 1 is a partial sectional view showing an embodiment of the catheter according to this invention, and FIG. 2 is a perspective view showing a state in which a balloon attached to the distal end of the catheter of the embodiment shown in FIG. 1 is inflated.

This catheter 1 includes a catheter body 2 made of an appropriate polymeric material, such as a fluororesin such as tetrafluoroethylene resin, polyvinyl chloride, polyurethane, polyethylene or other thermoplastic resin, or rubber such as silicone rubber or rubber latex.
As shown in FIG. 1, a narrow diameter section 3 approximately 50% smaller than the outer diameter of the catheter body 2 is provided at the distal end of the catheter via a tapered section 4. A flange-shaped protrusion 5 for locking the balloon is integrally formed with the balloon.

Next, to explain how the catheter 1 is used based on FIG. 2, a balloon made of an expandable elastic material such as silicone rubber or rubber latex is attached to the narrow diameter part 3 formed at the distal end of the catheter body 2. The open neck 11 of 10 is inserted to a position where it passes over the protrusion 5 and fixed tightly, and then inserted into a predetermined site in the body cavity, and the balloon 10 is injected with various fluids such as carbon dioxide gas, physiological saline, and contrast medium. Various treatments are performed by inflating the catheter and placing it in the body.

Note that when attaching the balloon 10 to the distal end of the catheter 1, since the balloon 10 has elasticity, the inner diameter of the opening neck 11, which is formed smaller than the outer diameter of the narrow diameter portion 3 of the catheter body 2, is enlarged to reduce the narrow diameter. It can be mounted by climbing over the protrusion 5 provided on the outer circumferential surface of the intermediate portion of the portion 3. The balloon 10 inserted to a predetermined position contracts in the radial direction due to its own elasticity and is tightly fixed to the narrow diameter portion 3 to maintain airtightness.

Due to the presence of the protruding portion 5, the balloon 10 will not come off from the catheter body 2 due to the impact of fluid ejection or when the catheter is pulled out, even without special additional fixing means such as adhesion.

In addition, as another embodiment, for example, as shown in FIG. , 6 is a protrusion other than the flange-like one shown in the above embodiment, which is not shown, but has an uneven surface, or a truncated cone whose diameter decreases toward the tip in the axial direction. It may be.

[Effect of idea]

As explained above, according to this invention, the tip of the catheter body has a narrow diameter part that is approximately 50% smaller than the outer diameter of the catheter body, and a balloon is attached to the outer peripheral surface of this narrow diameter part. Since the protrusions are formed integrally, when used as a balloon catheter, the balloon can be attached to the distal end of the catheter body very easily, and the balloon can be attached using glue or thread as in the past. Since there is no need to fix the catheter with a balloon, a balloon-equipped catheter can be obtained at low cost.

Furthermore, since adhesives, threads, etc. are not used, harmful substances will not be eluted into the body, or blood vessels will not be blocked due to detachment of the threads, resulting in a highly safe catheter.

In addition, it is preferable to provide the narrow diameter portion at the tip of the catheter body through a tapered portion and to form the protruding portion so that it is smaller than the outer diameter of the catheter body, as this allows for smoother insertion into the body. It is.

Note that this invention is not limited to the above-mentioned embodiments, and the shape of the protrusion may be changed or an electric current such as a nichrome wire may be placed inside the catheter in order to separate the inflated balloon from the catheter while retaining the fluid inside. Of course, various changes, combinations, additions, etc., such as insertion of a hot wire, are possible.

[Brief explanation of the drawing]

Fig. 1 is a partial longitudinal sectional side view of a catheter according to this invention, Fig. 2 is a perspective view showing a state in which another balloon is attached to the same catheter and inflated, and Fig. 3 is a view of a catheter showing another embodiment according to this invention. FIG. DESCRIPTION OF SYMBOLS 1... Catheter, 2... Catheter main body, 3... Small diameter part, 5, 6... Protrusion part.

Claims (1)

[Scope of utility model registration request] The distal end of the catheter body made of a polymeric material is integrally formed with a narrow diameter part that is approximately 50% smaller than the outer diameter of the catheter body, and a protrusion part for locking the balloon on the outer peripheral surface of the catheter body. Characteristic catheter.