The use of water ingestion to distinguish the gallbladder and duodenum on cholescintigrams.

Cholescintigraphic diagnosis of acute cholecystitis requires accurate assessment of gallbladder nonvisualization. Confusion may occur when the gallbladder overlies the duodenal sweep or when labeled bile pools in the duodenum. Gallbladder activity could not be differentiated from duodenal activity in 21 patients. The oral ingestion of 225 ml of water permitted successful differentiation of the gallbladder from the duodenum. In 25 control subjects, it was demonstrated that that volume of water did not have a cholecystokinetic effect.