| 摘要 |
A guidewire includes (i) a tapered core; (ii) an elongated non-radiopaque coil that is coincident with the core and extends over a distal portion of the core up to a proximal portion of a tapered end section of the core; and (iii) a radiopaque plastic tip that fits over the distal end of the core. The proximal end of the plastic tip may extend over the distal end of the non-radiopaque coil. The tip may then be attached to the coil by forcing the proximal end of the tip through the windings at the distal end of the coil. The distal end of the plastic tip extends slightly beyond the distal end of the core, to form a deformable bumper. The outer diameter of the proximal end of the plastic tip is the same as the outer diameter of the coil, which is the same diameter as proximal end of the core before its first taper. Accordingly, the guidewire has an essentially uniform outer diameter over its entire length. The durometer hardness of the plastic material used to form the tip may be adjusted, to alter the stiffness of the tip. Thus, the tip may be made stiffer or more flexible without changing the outer dimensions of the guidewire. The tip may also be tapered, as desired, to narrow the outer diameter of the distal end of the guidewire. A low friction coating may be added to the wire, to facilitate movement of the wire through the arteries. |
