| 摘要 |
The stent, which is self-expanding, is in the form of a tube which can be compressed for insertion into the human or animal body to relieve blocking of the oesophagus or other hollow viscera by tumours or other disorders. It is formed as a single or double conical helix or as a straight tube with cut slots allowing the tube to expand to different diameters along its length, so holding itself in place. A knitted or other tube is used to hold the stent in its compressed shape for insertion. A ratchet system may be provided on one or both surfaces of the collapsed tube so that once extended it will not collapse again. <IMAGE> |
