Opacification of acutely inflamed gallbaldder by i.v. cholangiography

In two patients with acute cholecystitis, there was opacification of the bile ducts and the gallbladder on the emergency intravenous cholangiogram. In one, the gallbladder had perforated, and by reducing intravesical pressure this may have relieved a functional obstruction of the cystic duct. No convincing explanation could be found in the second patient. These were the only two false negative cholangiograms in a small series of 30 patients.