The results of the EDAP multicenter trial of biliary lithotripsy in the United States. The EDAP Investigators Group.

The results of the EDAP International Corporation multicenter trial to test the efficacy and safety of its piezoelectric lithotripter in conjunction with ursodeoxycholic acid therapy for the treatment of gallstones are reported. Three hundred and sixty-two patients with one to three radiolucent calculi in a functioning gallbladder were studied. The mean stone size burden was 19 millimeters and was less than 30 millimeters in all patients. Lithotripsy treatment sessions were performed without analgesia or sedation in 72 per cent of the patients. Post-treatment complications were minimal. There were six patients with pancreatitis; two of whom had obstruction of the common bile duct by stone fragments. Three of these patients required endoscopic papillotomy. At the present time 120 of the patients (33.0 per cent) are stone-free and 197 (54.4 per cent) have residual fragments. Of the 163 patients in the study for at least six months, the stone-free rate is 44 per cent and for those individuals with a solitary stone less than 20 millimeters in size, the stone-free rate is 56 per cent. Biliary lithotripsy using piezoelectric techniques followed by adjuvant ursodeoxycholic acid is effective and is performed without significant pain or morbidity in the majority of patients.