Experimental tissue lesions related to extracorporeal lithotripsy of gallbladder.

Eighteen dogs were studied to determine the presence, extent and evolution of tissue lesions related to extracorporeal lithotripsy of the gallbladder under conditions similar to those encountered in clinical practice (electrohydraulic generator, ultrasonographic localization, prone positioning and 2,500 shocks delivered per session). Twelve dogs underwent lithotripsy 14 days after implantation of a 9 to 14 millimeter human stone in the gallbladder. The dogs were sacrificed one, 14 and 28 days after lithotripsy (four dogs at each date). Two dogs underwent implantation of stone but not lithotripsy and were sacrificed 14 days later. The last four dogs received only shock wave therapy and were sacrificed one (two dogs) and 14 (two dogs) days later. All calculi were completely fragmented into pieces less than 5 millimeters. Increases in leukocyte count (11 +/- 3.7 10(9) per liter) and alanine and aspartate aminotransferase levels (206 +/- 139 and 156 +/- 164 international units per deciliter, respectively) were seen after lithotripsy (p less than 0.05), but returned to normal during the next four weeks. Macroscopic hemorrhages were noted only in the dogs having undergone lithotripsy and were exclusively located in the organs lying in the path of the shock wave. Macroscopic hemorrhages were found in all six dogs sacrificed the day after lithotripsy and in two of the six dogs sacrificed 14 days later; one dog of the four sacrificed 28 days after lithotripsy still showed a large hemorrhage in the wall of the gallbladder. Microscopic abnormalities included congestion and hemorrhage of the same organs; although more discrete, congestion and hemorrhage were still present one month after shock wave therapy. Early and localized pulmonary fibrosis at the hypercellular stage was noted in two of the four dogs sacrificed at 28 days. The clinical implications for biliary lithotripsy upon humans include the necessity for intact coagulation parameters, strict avoidance of the bases of the lungs in targeting the stone and performing an ultrasonographic assessment of the wall of the gallbladder before repeating lithotripsy sessions, month apart.