Single Ultrasonic Crystal Techniques for Generating Uniform Temperature Distributions in Homogeneously Perfused Tissues

Abstruct-The Division of Neurosurgery at Stanford University began a hyperthermia program which has as its goal the development of an ultrasonic hyperthermia system for the treatment of malignant brain tumors. A single crystal technique is described for generating and dynamically varying shaped intensity distributions in ultrasonic fields. Using this technique it is possible to generate uniform temperature distributions in brain tissue over diameters ranging from 1 to 3 cm. Results comparing ultrasonic intensity distributions and corresponding thermal distributions are described which were mapped in dog brains.