| 摘要 |
<p>A catheter (10) and a method of manufacture thereof which includes a relatively rigid body (11) and a relatively soft tip (12) for decreasing the likelihood of injury or damage to tissue such as the wall of a blood vessel or the heart when the catheter (10) is used as a part of an invasive medical procedure such as angiography or angioplasty. The method includes the use of a core (15) which is sufficiently resistant to high temperatures to allow extrusion of polymeric material thereover in the process of forming the catheter (10). The core (15) controls the catheter's (10) inside diameter, and is sufficiently heat resistant to allow its use through all subsequent manufacturing process steps involving the formation of the soft tip (12). The method of the present invention prevents foreign material build up within the inner diameter of the catheter (10) during processing, eliminates the need for special fusion support mandrels during fusion of the soft tip (12) onto the catheter body (11), and maintains the integrity of the internal diameter of the catheter body (11) and soft tip (12) during the thermal and pressure processes of the manufacture. The invention also includes a novel method of sizing and fusing the soft tip (12) onto the catheter body (11) including the use of a piston member (29) about the core (15) which can apply pressure to the material forming the soft tip (12) at any time before, during or after the thermal heating step.</p> |
