CT findings in subacute perforation of the gallbladder: report on 5 cases.

Perforation of the gallbladder is a serious complication of acute and subacute cholecystitis which is rarely recognized before operation, either by clinical or radiological methods. Five cases of walled-off perforation of the gallbladder have been diagnosed by computed tomographic (CT) studies, within a period of less than one year. The studies were routinely made in the supine projection, with or without an intravenous injection of contrast medium. Scanning time was 4.7 seconds. The patients did not receive any pre-medication. CT demonstrated direct signs of the perforations: calculi outside the gallbladder; the ruptured segment of the wall. Indirect signs were also readily detected: localized abscesses, occasionally multiple or situated distant from the gallbladder; gallstones; thickening of the wall of the gallbladder. CT may have an important role in preoperative diagnosis of complicated acute cholecystitis and in the surgical management of patients with this condition, if ultrasound examination fails to establish the diagnosis or cannot be done for technical reasons.