Guidewire with adjustable stiffness

摘要

A medical guidewire system including an inner member having an outer diameter and an outer member having an inner diameter, the inner diameter being larger than the outer diameter. The inner and outer members are relatively slidable to adjust a stiffness of the guidewire system. The lumen of the outer member forms a gap for fluid flow therethrough. A connector has a first end portion connected to the outer member, a second end portion connected to the inner member and a fluid infusion channel communicating with the gap for injection of fluid through the gap to exit a distal portion of the outer member.

主权项

1. A medical guidewire having adjustable rigidity, comprising:
a first inner wire member having a first outer diameter and a closed distal tip, a second intermediate wire member having a second outer diameter larger than the first outer diameter, and a third outer wire member having a third diameter larger than the second outer diameter, the second wire member having a longitudinally extending opening to receive the first wire member for relative sliding movement with respect to the first wire member, the first wire member movable between a retracted position and an advanced position, the third outer wire member having a crimped proximal end forming a reduced diameter portion and a longitudinally extending opening to receive the second wire member for relative sliding movement with respect to the first and second wire members, the second wire member having a flared portion at a distal end thereof to engage the reduced diameter portion of the third wire member for an interlocking frictional engagement, and the first and second wire members have a clamping engagement, the interlocking frictional engagement and clamping engagement being configured to fix the relative longitudinal position of the first, the second, and the third wire members when the first wire member is in one of the retracted or advanced positions relative to the third wire member, wherein the first inner wire member, second intermediate wire member and third outer wire member are each independently slidable relative to one another to change the overall diameter, stiffness, and degree of pushability in advancement of the guidewire system, without a need to exchange the system or a portion thereof, and together the members function as a unitary structure such that a proximal region of said guidewire permits a medical device to be longitudinally advanced to a desired location in a patient.