An in vivo study of variations in local power absorption in high temperature ultrasound hyperthermia

The purpose of this research was to investigate temperature elevation variations caused by tissue location, tissue interfaces, and large blood vessels through a series of in vivo experiments using high power ultrasonic pulses. Results show that high temperature ultrasound hyperthermia does not suffer extensively from the tissue heterogeneities and even tissues within a few millimeters from an artery could be adequately exposed. Experimental results were compared with the temperature distributions predicted with computer simulations. The computer model studies indicate that matching simulated sound field distributions to the half power beam width measured in vivo provides an accurate estimate of experimental temperature distributions