A catheter with a distal end having a member formed from a hydrophilic composition is provided. The hydrophilic composition expands upon contact with an aqueous fluid to move the member from a quiescent state to an expanded state. The member may provide an open passageway in the quiescent state and be...http://www.google.com.au/patents/US20020193742?utm_source=gb-gplus-sharePatent US20020193742 - Valved over-the-wire catheter
