Preliminary abdominal films in oral cholecystography: are they necessary?

A survey of 45 radiologists with a special interest in gastrointestinal radiology showed that only 8% used a preliminary abdominal film for oral cholecystography. Review of 467 cases of oral cholecystography with preliminary films over a 1 year period disclosed 88 confirmed cases of cholelithiasis. Of these 88 cases, 27% had opaque gallstones visible on the preliminary film. In one-third of the cases, the opaque gallstones had a classic diagnostic appearance, while the remainder required oral cholecystography for confirmation. Opaque calculi were obscured by oral contrast material in 2% of cases. Other significant pathology on the preliminary films was found in 5.5% of the 467 cases.