Short-term effects of extracorporeal shock wave lithotripsy on the human gallbladder.

Extracorporeal shock wave lithotripsy (ESWL), whereby shock wave energy is focused upon gallstones causing their disintegration into fragments sufficiently small to be passed via the biliary system, offers a promising non-invasive alternative to surgery for gallstone disease. The tissue effects in humans of ESWL are poorly characterized and no systematic study of the tissue effects of ESWL by piezoelectrically generated shock waves has been published. Sixteen patients for elective cholecystectomy were therefore subjected to ESWL before surgery and detailed histology of the gall-bladders (including scanning electron microscopy of the mucosa) was compared with that from 20 age/sex-matched control cases. The gall-bladders treated by ESWL, in addition to showing the histological changes associated with chronic cholecystitis, showed serosal vasodilatation, mural oedema, and serosal and mucosal petechial haemorrhages focally over the entire surface. Between 10 and 90 per cent epithelial denudation was observed, but all cases showed surviving columnar epithelial cells in the crypts. No case showed vascular thrombosis, tissue necrosis, or acute inflammation. These tissue effects are likely to be reversible and unlikely to present a risk of perforation, although the long-term clinicopathological effects await investigation.