| 摘要 |
PURPOSE:To carry out the treatment of a stricture or the like (expansion treatment in particular) efficiently and to prevent the restricture of the part by making the deformation starting condition of a shape memory alloy member different at least at both ends an at the center in the longitudinal direction. CONSTITUTION:At the center of a main body 2, a lumen 7 is formed penetrating from the rear end to the front end in order to penetrate a guide wire 6, and a shape memory alloy coil 8 is installed at the position a little rear to a balloon 3. The coil 8 is made to have a relatively low transit temperature at the center 8b and a relatively high transit temperature at both ends 8a. A catheter is inserted up to a stricture of a blood vessel 13, and the balloon 13 is expanded by leading in a physiological salt solution or the like 4 to stop the flow of the blood or the humor temporarily. The physiological salt solution 10 is delivered from a leading port 11 at a constant temperature 50 deg.C, for example, the coil 8 is heated at the transit point or higher, the center 8b is expanded to the original form to expand the stricture 14, and then the expansion is transferred to both end sides gradually to expand the whole stricture 14. Then, the physiological salt solution in the balloon 3 is released, the balloon 3 is contracted, the catheter is removed, the coil 8 is left in the blood vessel, and the treatment is accomplished. |
