A porous tube suitable for use as a vascular graft prosthesis is disclosed. It is reinforced by external ribs, integral with the tube wall. These ribs are generally transverse to the tube axis and less porous than the wall. Suitable tubing can be made from polymers exhibiting a significant degree of...http://www.google.de/patents/US4550447?utm_source=gb-gplus-sharePatent US4550447 - Vascular graft prosthesis
