Floating gallbladder strangulation caused by the lesser omentum: report of a case.

Strangulation of the gallbladder by the omentum is extremely rare. We report what to our knowledge is only the second documented case of strangulation of a floating gallbladder by the lesser omentum. A 61-year-old Japanese woman presented to a local hospital after the sudden onset right upper quadrant pain. Her clinical features suggested a gallbladder volvulus, and the patient was referred to our hospital for investigation and treatment. Ultrasonography and computed tomography showed no cholecystolithiasis, but the fundus and body of the gallbladder were markedly swollen without wall thickening, whereas the neck of the gallbladder was normal. A narrowed, twisted area was seen between the body and neck of the gallbladder. Based on these findings, gallbladder volvulus was diagnosed and she underwent emergency laparoscopic cholecystectomy. The fundus and body of the gallbladder were grossly necrotic. The narrowest part of the gallbladder was tightly strangulated by the lesser omentum, but the gallbladder neck was normal. Histopathologic examination of the resected gallbladder showed ischemic changes in the wall of the fundus and body. This case highlights that the clinical features and imaging findings of a gallbladder strangulated by the lesser omentum are similar to those of gallbladder volvulus and that a positive outcome is dependent on a correct diagnosis and prompt surgical management.