Ultrasound physiotherapy treatment and calibration measurements in simulated tissue

The absorption, heating and relative intensities of ultrasonic beams used for physiotherapy are studied in water and in simulated tissue as a function of position in relation to the transducer head. It is found that the heating effects are significantly different from the beam profile shape. The effective area and depth of ultrasonic physiotherapy treatment is established for various situations, and tissue temperature rise curves are obtained. The results are appropriate for treatment planning. As an example, the typical volume of tissue effectively treated by ultrasound is a cylinder 6 to 8 cm in diameter and 1 cm deep.