JPH05184684A - Living body duct dilation tool - Google Patents

Abstract

PURPOSE:To provide a living body duct dilatation tool as a prosthesis which is composed of a shape memory alloy and also can surely be rested in a place in each duct organ. CONSTITUTION:A tool is equipped with tube 4 insertible into each duct organ of a living body, a prosthesis 3 which is inserted into the tube 4, and with a pusher 5 which pushes the prosthesis 3 out of the tip end of the tube 4. After the prosthesis 3 has been pushed in the inside of each duct organ out of the tip end of the tube 4, it is formed into a coil shape by the use a shape memory alloy which is restored into a dilated shape.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a living body, for example, a bile duct,
The present invention relates to a biological conduit dilator for expanding a narrowed portion of a duct of a tubular organ such as a blood vessel or an esophagus.

[0002]

2. Description of the Related Art Conventionally, prosthetes made of a shape memory alloy is introduced into a narrowed portion of a bile duct, and the outer diameter of the prosthesis is enlarged by using warm saline or the like to secure the circulation of bile. It is proposed in Japanese Laid-Open Publication No. 60-220030. The key to successful ductal dilation using such a biotracheal dilator is to guide the prosthesis as an expansion member to the stricture, and to increase the outer diameter of the prosthesis by heating it above body temperature. It is important to let

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and an object thereof is to provide an expansion member made of a shape memory alloy easily at the site of a tubular organ of a living body. It is an object of the present invention to provide a biological conduit dilator that can be reliably placed.

[0004]

In order to solve the above-mentioned problems, a biological conduit dilator of the present invention comprises a tube inserted into a tubular organ of a living body, and an expansion member inserted into the tube. A pusher for pushing the expansion member from the tip of the tube, the expansion member being pushed from the tip of the tube into the tubular organ,
It is composed of a shape memory alloy that restores its expanded shape. Therefore, the expansion member made of a shape memory alloy can be simply and surely placed at the site of the tubular organ of the living body, and the burden on the patient at that time can be reduced.

[0005]

Embodiments of the present invention will be described below with reference to the drawings. 1 (a) and 1 (b) show a first embodiment of the present invention, and FIG. 1 (a) is a cross-sectional view showing a state in which a biological duct dilator 1 is inserted into a narrowed portion of a bile duct 2. FIG. 2B is a sectional view showing a state in which the narrowed portion of the bile duct 2 is expanded by the prosthesis 3. The living body conduit dilator 1 includes a coiled prosthesis 3 (expansion member) formed by spirally swirling a band-shaped shape memory alloy, and a tube 4 for introducing the prosthesis 3 into a living body. . The transformation temperature of the shape memory alloy forming the prosthesis 3 is set to be equal to or higher than the body temperature. Specifically, the transformation start temperature from the low temperature side martensite phase to the high temperature side austenite phase is set to about 38 ° C. The transformation end temperature is set to around 45 ° C.

Inside the tube 4, there is a prosthesis 3
The pusher 5 for pushing out is inserted. The pusher 5 includes a flange 11 slidably provided at the rear of the storage position of the prosthesis 3 and a rod 12 connected to the flange 11.
The flange 11 pushes the prosthesis 3 out of the tip of the tube 4 into the living body. In addition, the flange 11 is provided with an outflow hole 13 for the physiological saline solution supplied through the tube 4.
3 through which physiological saline is passed,
Is heated to the transformation temperature.

Next, a method of using the thus constructed living body conduit dilator 1 will be described. First, an insertion portion of an endoscope (not shown) is inserted into a body cavity, and its tip is positioned near the duodenal papilla. Then, the living-body conduit dilator 1 is inserted into the forceps channel of the endoscope, the tube 4 is projected from the tip of the forceps channel, and the tip portion is inserted from the nipple opening portion, as shown in FIG. As shown, the bile duct 2 is positioned at the narrowed portion.

Next, the tube 4 and pusher 5 are operated so that the prosthesis 3 is pushed out from the tip of the tube 4, and the prosthesis 3 is positioned at the narrowed portion of the bile duct 2 shown in FIG. 1 (b). While detaining, 38
By injecting physiological saline at ˜45 ° C. through the outflow hole 13, the prosthesis 3 is heated above the body temperature, and as a result, the prosthesis 3 is restored to the memory shape. And
The prosthesis 3 placed in the stricture of the bile duct 2 is shown in FIG.
As shown in (b), the narrowed part of the bile duct 2 is expanded and placed. Then, the prosthesis 3 extruded from the tip of the tube 4 by the pusher 5 is
The narrowed part of the bile duct 2 is expanded. Therefore, the prosthesis 3 can be safely and reliably placed in the narrowed portion of the bile duct 2. Although the prosthesis 3 made of a unidirectional shape memory alloy is shown in this embodiment, a bidirectional shape memory alloy may be used.

FIGS. 2A and 2B show a second embodiment of the present invention. In this embodiment, one end of a plurality of wires 18 made of shape memory alloy is collectively fixed to a chip 19, The prosthesis 3 formed in a memory shape in which the other end side of 18 expands is used. Like the first embodiment described above, the prosthesis 3 is housed in the tube 4 and the tip of the tube 4 is pushed by the pusher 5. It is designed to be pushed out into the living body from. It can be used in the manner described above.

[0010]

As described above, the living body conduit dilator of the present invention has a tube to be inserted into a tubular organ of a living body, an expanding member to be inserted into the tube, and the expanding member to the distal end of the tube. And a pusher pushed out from the tube. The expansion member is made of a shape memory alloy that restores an expanded shape when the expansion member is extruded from the distal end of the tube into the tubular organ. Therefore, the expanding member made of a shape memory alloy can be simply and surely placed at the site of the tubular organ of the living body to expand the duct and secure the circulation of bile, for example. In addition, it is possible to reduce the burden on the patient when the expansion member is left indwelling, and it is possible to obtain a special effect.

[Brief description of drawings]

1 (a) and 1 (b) show a first embodiment of the present invention, in which FIG. 1 (a) is a sectional view showing a state in which a biological duct dilator is inserted into a bile duct, and FIG. It is sectional drawing which shows the state which expanded the narrowed part.

2 (a) and 2 (b) show a second embodiment of the present invention, and FIG. 2 (a) is a cross-sectional view showing a state where a living-body duct expanding member is housed in a tube. 8] is a sectional view showing a state in which the expansion member is extruded from the tube and expanded.

[Explanation of symbols]

1 ... Biological duct dilator, 2 ... Bile duct, 3 ... Prosthesis,
4 ... Tube, 5 ... Pusher, 11 ... Flange, 12 ...
rod.

Claims (1)

[Claims] 1. A tube which is inserted into a tubular organ of a living body, an expansion member which is inserted into the tube, and a pusher which pushes out the expansion member from a tip of the tube. A living body conduit dilator configured by a shape memory alloy that restores an expanded shape when extruded from the distal end into the tubular organ.