Normally the gallbladder is well-attached to the liver. Rarely the gallbladder may be mobile and undergo torsion.
Clinical features:
(1) right upper quadrant pain, which may be intermittent
(2) nausea and vomiting
(3) fever
(4) increased mobility of the gallbladder ("floating")
(5) abdominal hernia, focal adhesion or other factor favoring rotation
Imaging studies:
(1) thickening of the gallbladder wall with edema and/or hemorrhage
(2) absence of blood flow in the gallbladder on Doppler ultrasonography
(3) whirl sign (twisted cystic artery)
(4) on MRCP there is no clear connection through the cystic duct
If the rotation of the gallbladder is > 180 degrees, then it is considered complete, else incomplete.
Complications:
(1) gangrenous cholecystitis
