The diagnosis of acute complicated cholecystitis by Tc-99m sulfur colloid liver imaging.

Increased hepatic activity surrounding the gallbladder fossa during Tc-99m SC liver imaging was observed. Subsequent Tc-99m IDA biliary imaging showed similar findings in the face of nonvisualization of the gallbladder--the classic "rim sign." Surgery confirmed the diagnosis of complicated acute cholecystitis. This case indicates that a rim sign may be seen with either Tc-99m SC or Tc-99m IDA imaging and may have the same diagnostic significance in both.