Guidewire

Abstract

A guidewire (1) includes a core shaft (2), a coil body (3), and a tip portion (5). The coil body (3) covers a distal end portion of the core shaft (2). The tip portion (5) is formed by joining a distal end of the coil body (3) and a distal end of the core shaft (2) using metal solder. The tip portion (5) includes an outside diameter decreasing portion (5b) and a rounded, e.g. spherical cap-shaped or hemisphere-shaped, portion (6). The outside diameter of the outside diameter decreasing portion (5) decreases linearly in a direction of a distal end. The rounded portion (6) is positioned at a distal end of the outside diameter decreasing portion (5).

Description

technical field [0001] The invention relates to a wire. Background technique [0002] Conventionally, various guide wires have been proposed for insertion into tubular organs such as blood vessels, digestive tract, and urethra, or tissues in the body to guide medical equipment and the like to target sites. In addition, in recent years, internal medical treatment using guide wires has been performed in many cases for vascular occlusion lesions that cause ischemic diseases. Among them, it is known that there are small pathways (hereinafter referred to as microchannels) in the vascular occlusion lesion, and it is required to improve the insertability and passability of the guidewire to the microchannel in the vascular occlusion lesion for the guide wire currently being developed. [0003] For example, Patent Document 1 (US Patent Publication No. 2007 / 0185415 specification) describes a lead wire having a front end joint formed by welding at the front end, the outer diameter of ...

AI Technical Summary

Problems solved by technology

[0005] However, since the lead wire described in Patent Document 1 is welded to form a tip joint, it is necessary to melt the core material or coil material around the tip joint once, and the core material or coil will be in an annealed state due to the thermal influence during welding, so that The mechanical strength is greatly reduced

In addition, in the case where the core material and the coil are formed of different kinds of metals, since the melting point of the core material is different from that of the coil, sufficient welding strength cannot be obtained, resulting in a further decrease in the mechanical strength of the tip joint.

Therefore, when the guidewire described in Patent Document 1 is inserted into the vascular occlusion lesion, the leading end of the guidewire is deformed, and it does not have sufficient insertability into the vascular occlusion lesion.

[0006] In addition, there are problems in that it is difficult to form the front end joint into a spherical shape, and a lot of work time is required for subsequent tapering

[0007] In addition, although the guidewire described in Patent Document 2 improves the insertion property into the vascular occlusion lesion by the protrusion provided at the distal end of the distal end joint, the outer diameter is different from the base end of the protrusion to the front end of the distal joint. As a result, the guide wire described in Patent Document 2 does not have sufficient passability to the vascular occlusion lesion.

Images