BIOPHYSICAL EFFECTS OF HIGH-ENERGY PULSED ULTRASOUND ON HUMAN-CELLS

Human benign and malignant cells of different human origin (pancreas, liver, kidney, pharynx, tongue, lip) were exposed to high-energy pulse d ultrasound (HEPUS) in vitro to evaluate the effects of various physi cal parameters and sonication conditions on cell viability. This inclu ded the number of pulses, focal pressure, pulse repetition rate, pulse shape, cell suspension volume, water level of the basin and cell dens ity. Cell viability was found to depend significantly on the number of pulses (exponential), the focal pressure (linear) and the pulse repet ition rate (minimum at 1 Hz). Other parameters showed no marked influe nce. Furthermore, electron microscopy revealed intracellular damage, a nd proliferation rates of cells surviving sonication were normal after HEPUS exposure. The experimental piezoelectric ultrasound transducer used in the experiments generated oscillating bipolar pulses with high negative pressure amplitudes. Measurements were made of the pulse sha pe and ultrasonic field of the experimental device and of a convention al lithotripter for comparison. Copyright (C) 1996 World Federation fo r Ultrasound in Medicine & Biology.