Significance of nonshadowing focal opacities at cholecystosonography.

Nonshadowing focal opacities within the gallbladder lumen are a frequent finding with cholecystosonography. This study describes a prospective analysis of 125 patients with this finding. In 36 patients surgical proof was obtained. It was found that nonshadowing echogenic foci in the gallbaldder can be separated into two distinct categories and that the incidence of gallstones can be determined for each. The categories are (a) nonshadowing echogenic foci less than 5 mm in size (incidence of gallstones is 81% for those patients coming to surgery) and (b) a fluid-fluid level or sludge (incidence of gallstones is less than 10% for those coming to surgery).