Guidewire and method therefor

A method of making a guidewire, the method comprising:

• placing a polymer jacket over a core wire, the core wire including a length including a first portion having a first thickness and a second portion having a second thickness, the first thickness being smaller than the second thickness;
• placing heat shrink tubing over the polymer jacket;
• and
• applying heat to the polymer jacket, the heat shrink tubing, and the core wire to reflow the polymer jacket and fuse the polymer jacket to the core wire, wherein the heat shrink tubing shrinks when heated to constrain and solely apply pressure to the polymer jacket during reflowing of the polymer jacket to maintain the positioning and distribution of the polymer jacket around and in proximity to the core wire with application of the heat to the polymer jacket, the heat shrink tubing, and the core wire, such that a first profile of the polymer jacket and the core wire at the first portion of the core wire is smaller than a second profile of the polymer jacket and the core wire at the second portion of the core wire, wherein the polymer jacket forms a layer of a polymer material of substantially uniform thickness along the length of the core wire, thereby substantially following a shape of the core wire.

A method of making a guidewire, the method comprising:

• placing a polymer jacket over a core wire, the core wire including a length including a first portion having a first thickness and a second portion having a second thickness, the first thickness being smaller than the second thickness, the first portion of the core wire being proximate a distal end of the core wire, the second portion of the core wire being disposed between the first portion and a proximal end of the core wire;
• placing heat shrink tubing over the polymer jacket;
• and
• applying heat to the polymer jacket, the heat shrink tubing, and the core wire to reflow the polymer jacket and fuse the polymer jacket to the core wire, wherein the heat shrink tubing shrinks when heated to constrain and solely apply pressure to the polymer jacket during reflowing of the polymer jacket to maintain the positioning and distribution of the polymer jacket around and in proximity to the core wire with application of the heat to the polymer jacket, the heat shrink tubing, and the core wire, such that a first profile of the polymer jacket and the core wire at the first portion of the core wire is smaller than a second profile of the polymer jacket and the core wire at the second portion of the core wire, the first profile including a thickness of less than 0.014 inches, wherein the polymer jacket forms a layer of a polymer material of substantially uniform thickness along the length of the core wire without trimming down the polymer jacket, thereby substantially following a shape of the core wire.