| 摘要 |
<p>A unitary, flexible, substantially noncollapsible catheter tube (30) of biocompatible material is comprised of hard and soft regions, the hard regions being ring shaped. The hard regions (20) provide sufficient rigidity to the tube to prevent collapse under normal usage as the interior and exterior pressures vary. The soft regions (10) provide sufficient flexibility to allow contoured placement of the tube. The hard regions can be created by exposing a polymer in the tube to radiation. The hard regions can also be created by periodically adding a harder material to the tube. <IMAGE></p> |
