US Patent 7229455 Ultrasonic calculus treatment apparatus

An ultrasonic calculus treatment apparatus includes a longitudinal-vibration piezoelectric oscillator for vibrating in the axial direction of an ultrasonic transmitting member and a torsional-vibration piezoelectric oscillator for vibrating about the axial direction, and further includes driving circuits for driving the piezoelectric oscillators at respective resonance frequencies and a mode selection switch for permitting the oscillators to vibrate independently or in combination, so that lithotripsy can be performed effectively in accordance with the size of a calculus or a function of an operating tool.