Mode of action of a surgical electronic lithoclast--high speed pressure, cinematographic and schlieren recordings following an ultrashort underwater electronic discharge.

In order to investigate the mode of action of the electrical discharges from a surgical electronic lithoclast in shattering bladder stones high speed pressure-time recordings were made. The results indicated effects similar to those following an underwater detonation of high explosive. Subsequent high speed photographic analysis confirmed this. Calculations based on the results suggested that the shock waves and pressure pulses generated were of a potentially hazardous magnitude and that gas-containing bowel close to the bladder might be at particular risk as well as solid tissue as the bladder wall. Photographic data also suggested that danger might be incurred by the use of similar devices in a small enclosed space such as the ureter or renal pelvis.