The value of the fatty meal in oral cholecystography.

A fatty meal was given to 231 patients who had a well-visualized gallbladder with no stones. The radiological diagnoses on fluoroscopic spot films made before and after the fatty meal were compared. Only one case was diagnosed differently after the fatty meal. In 4 patients the post-fat film was useful in confirming a suspected diagnosis. Indications for administration of a fatty meal include (a) overlying gas shadows, (b) differentiation of a stone from a polyp, (c) adenomyomatosis, (d) a distended gallbladder, and (e) suspected common bile duct obstruction. In the absence of these indications, the time, effort, and cost involved in making the post-fat film are not justified by the additional diagnostic information obtained.