TISSUE ABLATION USING AN ACOUSTIC WAVE-GUIDE FOR HIGH-INTENSITY FOCUSED ULTRASOUND

High-intensity focused ultrasound (HIFU) has been shown capable of sel ective tissue destruction in humans, with promise as a tool for ablati on of tumors, although one practical problem is reflection of sound at gas or bony interfaces within the body. We evaluated a water-filled c ylindrical metal tube as a waveguide for HIFU, since such a general te chnique might be useful for ablation of otherwise inaccessible tumors in the body. Our studies indicate that such a waveguide is capable of propagating HIFU from a piezoelectric source, with resultant heating o f tissue specimens to greater than 80 degrees C, causing focal tissue destruction. (C) 1997 American Association of Physicists in Medicine.