Bouveret Syndrome: Excavating a Unique Geode-Like Gallstone With White Crystal Inner Core From Duodenum

Bouveret syndrome is a rare complication of cholelithiasis where a gallstone creates a cholecystoduodenal fistula resulting in gastric outlet obstruction. We present a case of a 66-year-old man with Bouveret syndrome with unique stone characteristics, which was successfully extracted using electrohydraulic lithotripsy during endoscopic retrograde cholangiopancreatography. The stone had an unusual appearance of a white crystal inner core surrounded by a dark brown covering resembling a geode.