[10 years of sonographic diagnosis of gallstones--what do surgical statistics tell us about its reliability?].

The efficiency of sonographic gallstone diagnosis was checked retrospectively by examining a group of surgical patients. In 724 patients examined preoperatively during 1974 to 1981, cholecystectomy was performed four times on the basis of a false positive sonographic diagnosis. False negative findings were more frequent (n = 33); in one-half of the total number of these false negative cases the reason for overlooking the gallstones had been the presence of hydrops of the gallbladder (hydrocholecystis) in the acute stage. Nevertheless, sonographical diagnosis for performing cholecystectomy was easy to make in cases with hydrops of the gallbladder. No assessment of the gallbladder was possible in 6 cases only out a total of 724 cases (0.8%). Sensitivity of sonographic diagnosis was about 95.9%; after introduction of modern linear-array and sector scanners in 1983 the sensitivity increased to 98.4%. At that time radiological examination was hardly conducted preoperatively. On the whole, no statistically significant differences were seen in comparison to radiological examination methods when introducing sonography.