Shaping of Focused Ultrasound Beams to Expedite Thermal Necrosis in Tumor Therapy

Frederic Lizzi
Our laboratories are investigating ultrasonic beams with asymmetric shapes to expedite the production of therrnal-Iesion matrices in tumors. The beams are generated using rectangular strip electrodes plated on spherical-cap ceramic transducers; focal-plane beam patterns consist of lobes confined within elliptical-rather than circular-cross-sections, Theoretical modeliing and ;n-vitro experiments have shown that thermal diffusion between these lobes can produce lesions with the desired
more » ... cross sections. Eficient lesion matrices can be deployed by translating such transducers along the short axis of the lesion cross-section; this will produce necrosis in broader regions than with typical beams and should significantly shorten the total time needed to treat entire tumors in the eye and other organs. work supported by NIH Granl EY10369.]