Biological effects of low-temporal, average-intensity, pulsed ultrasound.

Studies with both plant and animal tissues show that, when the tissues contain micron-sized, stabilized gas bodies, pulsed ultrasound can produce damage at very low time-averaged intensities. However, it is the temporal peak intensity rather than the time-averaged intensity that is closely correlated with the effects observed. The data suggest that there may be thresholds for damage at peak intensities within an order of magnitude of 10 W/cm2.