Analysis of a multielement ultrasound hyperthermia applicator

An unfocused multielement ultrasound applicator was developed for hyperthermia treatment of superficial tumors. The applicator contains sixteen 3.8-cm(2) individually controllable elements on a 15.2-cm(2) piezoelectric ceramic plate. The acoustical power output of each element can be independently applied to facilitate uniform heating throughout the treatment area while minimizing undesired heating in normal tissues. The performance of the applicator was examined by measuring acoustical power output and beam profiles. The results of this analysis indicated that the applicator is capable of producing required therapeutic output levels with excellent localization and control of the power deposition.