Ultrasonic studies of gall-bladder stones.

Measurements of ultrasonic speed, attenuation and other derived physical properties of gallstones, in vitro, have been evaluated and reported. A double-probe-contact through-transmission technique was used; the average values of ultrasonic speed and attenuation were found to be 1897 m s-1 and 10.2 dB cm-1, respectively, at 2.5 MHz (the value of speed thus being about 25% higher than that in water or soft biological tissues). The object of the present study was to determine the characteristics of stones to permit the optimization of a disintegrator design.