초록 ▼

A catheter and guide wire in which at least a distal end portion of a catheter body or guide wire is formed of a shape memory-specialized metal having shape memory property, but free from superelasticity or pseudoelasticity at least at the body temperature, have high safety and improved operability

A catheter and guide wire in which at least a distal end portion of a catheter body or guide wire is formed of a shape memory-specialized metal having shape memory property, but free from superelasticity or pseudoelasticity at least at the body temperature, have high safety and improved operability as compared with prior art ones and are advantageously used in a wide range of examination and treatment, especially in angiography, angioplasty, embolization, foreign matter removal and recovery, calculus capture and so on.

대표청구항 ▼

1. A catheter characterized in that at least a distal end portion of a catheter body is formed of a shape memory-specialized alloy having shape memory property, but free from superelasticity or pseudoelasticity at least at a body temperature, and the distal end portion made of the shape memory-speci

1. A catheter characterized in that at least a distal end portion of a catheter body is formed of a shape memory-specialized alloy having shape memory property, but free from superelasticity or pseudoelasticity at least at a body temperature, and the distal end portion made of the shape memory-specialized alloy is shape memorized to a circular arc such that it may recover its memory-shape with a local radius of curvature along the distal end portion in the range of 200 mm to less than ∞ mm at the body temperature. 2. A catheter characterized in that at least a distal end; portion of a catheter body is formed of a shape memory-specialized alloy having shape memory property, but free from superelasticity or pseudoelasticity at least at a body temperature, and when at least a distal end portion of said catheter body is deformed at an angle of 30 to 90 degrees at the body temperature, it takes not less than 0.3 seconds to recover upon unload of the deforming force. 3. A catheter characterized in that at least a distal end portion of a catheter body is formed of a shape memory-specialized alloy having shape memory property, but free from superelasticity or pseudoelasticity at least at a body temperature, and at least a distal end portion of said catheter body is formed of a metal material which has a yield force of not higher than 8.8 N, a recovery force of not higher than 2.9 N and a residual strain of not lower than 0.2 mm when a three-point bending test is carried out using a cylindrically shaped tube entirely made of the metal material having an outer diameter of 875 μm and an inner diameter of 750 μm. 4. A catheter characterized in that at least a distal end portion of a catheter body is formed of a shape memory-specialized alloy having shape memory property, but free from superelasticity or pseudoelasticity at least at a body temperature, at least the distal end portion of the catheter body is prepared from heat treating a Ni--Ti base shape memory alloy having shape memory property and superelasticity or pseudoelasticity at least at the body temperature so that said Ni--Ti base shape memory alloy is converted into a shape memory-specialized alloy in which the superelasticity or pseudoelasticity of the shape memory alloy is non-existent with its shape memory property maintained, and at least the distal portion of the catheter body is deformed at an angle of 30 to 90 degrees at least at the body temperature and when deforming force is unloaded, restoration takes a time of not shorter than 0.5 seconds. 5. The catheter of claim 1, 2, 3 or 4 wherein the catheter body is entirely formed of said shape memory-specialized alloy. 6. The catheter of claim 1, 2, 3 or 4 wherein the distal end portion of the catheter body is formed of said shape memory-specialized alloy, and a remainder of the catheter body is formed of a shape memory alloy having shape memory property and superelasticity or pseudoelasticity at least at the body temperature. 7. The catheter of claim 1, 2, 3 or 4 wherein the distal end portion made of the shape memory-specialized alloy is tapered. 8. The catheter of claim 1, 2, 3 or 4 wherein the distal end portion made of the shape memory-specialized alloy is shape memorized to an angle segment such that it may recover a memory-shape with an angle in the range of 0 to 120 degrees at the body temperature.