Abstract: The present invention provides an apparatus and a method for using an ultrasonic probe to remove an occlusion in vascular access devices including fistulas, grafts, catheters and subcutaneous access devices. The ultrasonic probe is inserted into the vascular access device and a section of a longitudinal axis of the ultrasonic probe engages the occlusion. A transducer transmits an ultrasonic energy from an ultrasonic energy source that produces a transverse ultrasonic vibration along the longitudinal axis of the ultrasonic probe. The transverse ultrasonic vibration of the ultrasonic probe provides a plurality of transverse anti-nodes along a portion of the longitudinal axis of the ultrasonic probe that cause a cavitation in a medium in communication with the ultrasonic probe to ablate the occlusion.

Abstract: An ultrasonic medical device comprising an ultrasonic probe and a collet assembly for probe attachment and detachment, and a method of removing occlusions in blood vessels using the ultrasonic medical device. The probe detachability allows insertion, manipulation and withdrawal independently of a device body. The collet assembly comprises a compression clamp capable of releasably receiving the probe, and a compression housing that initiates a minimal area “line-contact” between the collet assembly segments upon engagement. A line-contact lip ensures consistent and repeatable contact between the compression clamp and the compression housing at a predetermined location to provide a consistent closing force on the probe for any selected tightening torque. The line-contact between the collet assembly segments provides efficient ultrasonic energy transfer from an ultrasonic energy source to the probe thereby increasing the probe efficiency during tissue ablation.