An elongate blunt-ended hollow tube is affixed on the distal end of a flexible catheter. A cutting edge along one side of a lengthwise slot in the tube wall cuts off irregularities from the inside of a vessel and feeds them into the hollow interior of the tube as the catheter is rotated....http://www.google.ca/patents/US4020847?utm_source=gb-gplus-sharePatent US4020847 - Rotating cutter catheter
