Preoperative Diagnosis of Gallbladder Agenesis: A Case Report.

Gallbladder agenesis (GA) is a rare congenital malformation with less than 500 reported cases. Often an incidental finding intraoperatively or in postmortem autopsies, the first reported case dates back to 1701. We discuss the case of a 21-year-old female presenting with classic biliary symptoms who, on imaging, failed to have a visualizable gallbladder. Initial ultrasound (US) reported a non-visualized gallbladder with gallbladder contraction as a possible explanation. More advanced imaging allowed for the preoperative diagnosis, thus preventing an unpleasant intraoperative surprise. As imaging techniques continue to advance, unnecessary operations can hopefully be avoided, albeit a difficult diagnosis to make.