Numerical Modeling of Therapeutic Ultrasound

The objective is to develop, validate, and distribute numerical simulation software forcomprehensive computer modeling of therapeutic ultrasound. The principal application areas are focusedultrasound for noninvasive treatment of cancer and benign prostatic hypertrophy. Emphasis is ontherapy methods that minimize blood perfusion effects via relatively fast, localized heating of tissue.The principal modeling issue is rapid, nonlinear change in tissue and ultrasound propagation in the focus,requiring a combination of non linear thermal and ultrasound modeling for both continuous and transientmechanical waves. No comprehensive modeling capability of this type exists in the medical communitytoday. The analytical bases for this numerical simulation research are time-domain finite elementmethods. Temporal integration of the finite element equations provides complete linear or nonlinearsolutions of the ultrasound and bioheat equations in two-or three-dimensional (2D or 3D) domains thatconform to tissue boundaries. The aim is to develop the necessary software and make it accessible toall interested parties, both commercial and academic. The code will run on UNIX workstations and thenext generation of personal computers (Pentium and PowerPC). The foundation finite element code,PZFlex is fully operational and currently sold for transducer design.