Medical guide wire assembly of the medical guidewire and the microcatheter, and assembly of the medical guide wire and a balloon catheter and a guiding catheter

摘要

PPROBLEM TO BE SOLVED: To provide a medical guide wire capable of improving the operability by forming a buoyancy chamber in the inside at the distal end which may easily hang down with the action of the gravity, and improving the forward propulsive force by utilizing the pressure resistance and difference in the specific gravity. PSOLUTION: The buoyancy chamber 5 is composed of a brazed part 10, an air-tight wall 11 and resin coating 4 inside a coil tip 31 of the guide wire 1. The resin coating 4 forms a tubular film, whose outer diameter is smaller than the outer diameter of a coil body 3, in the gap C between coil wires of the coil body 3 when the coil body 3 is extended in the moisturized state. Accordingly, the guide wire can be inserted deep into a blood vessel by utilizing the action of the buoyancy chamber together with the increase of the pressure resistance. The resin coating 4 is composed of a hydrophobic first coating layer 41 and a hydrophilic second coating layer 42. As the specific gravity of the resin coating 4 becomes smaller from the first layer 41 toward the second layer 42 side, the weight of the guide wire can be reduced to contribute to the improvement of the buoyancy performance. PCOPYRIGHT: (C)2008,JPO&INPIT