An ultrasonic angioplasty device comprising an elongate ultrasound transmission member having a proximal end attachable to an ultrasound generating device and a bulbous distal head or probe formed on the distal end thereof for effecting ablative treatment of an occluding lesion. The ultrasound transmission member may be formed of one or more superelastic metal alloys such as NiTi (50 at. % Ni). A guidewire lumen may be formed in the distal head or probe to permit passage of a guidewire therethrough. Portions of the ultrasound transmission member may be curved or bent. Portions of the ultrasound transmission member may be tapered or narrowed. One or more surface disruptions may be formed on the distal head or probe to improve treatment efficacy. An increased hardness coating or outer skin may be formed on the ultrasound transmission member. The device of the present invention may be incorporated into an angioscopic device.