Cholecystosonography: an approach to the nonvisualized gallbladder.

B-scan echography was employed in the evaluation of 12 patients whose gallbladders remained nonvisualized after double-dose oral cholecystography. The gallbladder was identified by ultrasound in all but 1 patient. Gallbladder size was assessed and specific diagnoses of chronic cholecystitis, empyema, obstruction or dilation, and gallstones were made by this technique. When a normal gallbladder is seen by ultrasound, it indicates a cause other than primary biliary disease for nonopacification. Cholecystosonography is considered a valuable supplementary study when adequate opacification of-the gallbladder cannot be achieved.