Anatomical Pitfall in Calot's Triangle: Safe Cholecystectomy in the Presence of Moynihan's Hump

Laparoscopic cholecystectomy is one of the most frequently performed surgical procedures, with a low overall complication rate; however, anatomical variations within Calot's triangle can pose significant risks if not properly recognized. Among these, Moynihan's hump - a tortuous right hepatic artery (RHA) passing unusually close to the gallbladder and cystic duct - represents a rare but important vascular anomaly. We report the case of a 25-year-old woman with symptomatic cholelithiasis who underwent laparoscopic cholecystectomy. Intraoperatively, a tortuous RHA, forming a Moynihan's hump with a short cystic artery arising from it, was encountered. Careful dissection above the sulcus of Rouviere allowed the attainment of the critical view of safety, ensuring safe ligation and division of the cystic artery and duct. The patient's postoperative recovery was uneventful. Moynihan's hump is a potential anatomical pitfall that may lead to inadvertent vascular or biliary injury if unrecognized. Awareness of such variations, meticulous dissection, and strict adherence to the critical view of safety are essential to preventing operative complications and ensuring safe outcomes in laparoscopic cholecystectomy.