Effervescent gallbladder: sonographic findings in emphysematous cholecystitis.

We report a case of emphysematous cholecystitis with the sonographic appearance of an "effervescent gallbladder"--a large amount of gas bubbles rising like bubbles in a glass of champagne from the dependent part of the gallbladder and floating to the nondependent part. The etiology of this finding was acute obstruction of the distal common bile duct by a stone and purulent cholangitis. Short-term follow-up sonography is important to confirm the diagnosis of cholecystitis.