A medical guide wire, a method of making the same, an assembly of microcatheter and guiding catheter combined with the medical guide wire

Abstract

In a medical guide wire (1), a flexible core wire (2) is made of austenitic stainless steel wire treated with a solid solution procedure, and tightly drawn with a whole cross sectional reduction ratio as 90%-99%. Upon forming a head plug (41) at a distal end by welding a distal end tip of the core wire (2) to a distal end tip of a helical spring body (3), a eutectic alloy is used as a welding member (4). The eutectic alloy has a predetermined melting temperature point so as to reduce a thermal influence against the core wire (2), thereby improving a mechanical strength property of the core wire (2) so as to lengthwisely reduce and diametrically minimize the head plug (41).

Description

technical field [0001] The present invention relates to a medical guide wire which improves the mechanical strength characteristics of the welded part when a core wire and a helical spring body are welded at the distal tip thereof by a welding element and a method of manufacturing the same. Background technique [0002] Generally, a medical guide wire (referred to simply as a guide wire) is made thin so that the guide wire is inserted into the body vasculature. In view of the thinned wires, it is necessary to give the guide wires mechanical requirements with reliable safety measures for the human body. For this purpose, various types of inventions have been proposed. [0003] In Japanese Laid-Open Patent Application No. 2003-164530 (referred to as the first reference), the first reference discloses a medical guide wire in which the longitudinal dimension of the head plug is determined so that the head plug passes through the patient's vasculature. diseased areas, thereby e...

AI Technical Summary

Problems solved by technology

[0010] In the existing medical guide wires, there is no technical suggestion that the core wires (stainless steel wires) are highly drawn by tight drawing operations to produce highly drawn core wires, and that fusible alloys are used as welding elements (soft soldering) or brazing material) that resists the thermal influence of the mechanical strength characteristics to be considered when forming the header plug by welding the core wire to the helical spring body

[0011] Furthermore, there has been no technical suggestion to date to longitudinally reduce and diametrically minimize the tip plug, thereby enabling the operator to insert the tip plug deeply into the sinuous or continuously sinuous passages of blood vessels

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