Methods and devices for cutting tissue

摘要

A catheter which includes a cutting element (4B) having one or more raised (26B) elements is provided. The cutting element has a cup- shaped surface at the distal end that may be smooth and continuous except for the raised elements. The raised elements have a curved surface (30B) that is adapted to redirect cut particles of material when said curved surface is rotated so that a fluid vortex directing said cut particles towards one or more of the axis of rotation of the cutting element, the catheter axis, or a particle collection chamber is created. In further aspects of the invention, a cutting element oscillates in a direction roughly parallel to the axis of rotation of the cutting element.