Physical laws of cholesterol gallstone fragmentation.

Efficient fragmentation is the most important prerequisite for successful treatment of gallstones by extracorporeally induced shock waves. No data are available on the amount of energy necessary for stone disintegration and on the threshold energy below which no further fragmentation occurs. We therefore performed an in vitro investigation on human cholesterol gallstones to elucidate physical laws governing shock-wave lithotripsy.

In vitro study to elucidate the physical laws concerning the fragmentation of both solitary and multiple artificial stones.

These in vitro studies define the basic physical laws regarding work and energy for the successful fragmentation of human gallstones. For this purpose a standardized stone model was used consisting of plaster and glass microspheres with physical properties similar to those of human gallstones. All experiments were performed using the lithotripter model MPL9000 (Dornier).