Anomaly of the gallbladder lying extraperitoneally in the internal oblique muscle: report of an unusual case.

A gallbladder occupying internal oblique muscle rather low down in the right lower abdomen, is reported. The preoperative diagnosis was an abdominal wall tumor. The operation showed that we were dealing with a gallbladder which contained stones, and which had a relatively long cystic duct. The gallbladder was very loosely attached to the liver-bed with a long mesentery. Such a variation in the gallbladder position has only once been described in the previous literature.