Patent ID: 6984220

Claim:
An ultrasonic longitudinal-torsional tissue dissection system having only a single source of vibration consisting of only a single electro-mechanical transducer for receiving alternating electrical current and voltage from an ultrasonic generator, said transducer having a point of mechanical contact with a resonator, said transducer producing at said point of contact only a single type of vibration selected from the group consisting of longitudinal vibration and torsional vibration, said transducer immediately upstream from said point of mechanical contact having only said single type of vibration, said resonator being mechanically joined to a tip shaped for cutting biological tissue, and at least a portion of said resonator having an inhomogeneous cross section which at said resonator converts the single type of vibration into a combined longitudinal-torsional vibration upstream from said tip for imparting the longitudinal-torsional vibration to said tip and said inhomogeneous portion comprises a section having a rectangular cross section having the shape of a helical spiral.