abstract |
A catheter equipped with an expansible member for expanding a constricted portion inside a blood vessel, comprises an inner tube having a first lumen whose tip is open; an outer tube disposing coaxially with the inner tube, having the tip thereof at a position recessed by a predetermined length from the tip of the inner tube and forming a second lumen between it and the outer surface of the inner tube; a contractible or foldable expansible member having the tip portion fitted to the inner tube and the proximal portion fitted to the outer tube, and communicating with the second lumen near the proximal portion; a first opening communicating with the first lumen disposed at the proximal portion of the inner tube; a second opening communicating with the second lumen disposed at the proximal portion of the outer tube; and a rigidity imparting member disposed in at least one of the inner and outer tubes so as to extend in an axial direction. A method of production of an expansible member for use in a catheter equipped with an expansible member, comprises a step of forming a thermoplastic resin tube and heating an expansible member forming portion of this tube; a step of disposing the heated expansible member forming portion of the tube in an expansible member molding die the inner surface of which is formed in a shape obtainable when the expansible member is inflated; a step of bringing the heated expansible member forming portion of the tube disposed in the expansible member molding die into close contact with the inner surface of the molding die by pressurizing the inside of the tube; a step of cooling the expansible member forming portion of the tube; a step of removing the expansible member molding die from the tube; and a step of cutting the molded expansible member forming portion off the tube. |