Cystic artery arising from the gastroduodenal artery with sequential extra- and intratriangular segments: an anatomical case report

This study aimed to describe the topographic and morphometric features of a cystic artery arising from the gastroduodenal artery and exhibiting both extra- and intratriangular segments.

The variation was identified during routine dissection of the hepatobiliary region of a formalin-fixed 56-year-old male cadaver. The extra-hepatic bile ducts and adjacent arterial structures were sequentially exposed. The origin, course, topographic relationships, length, and external diameter of the cystic artery were assessed. Photographic documentation was obtained during dissection.

The cystic artery arose as a single trunk from the gastroduodenal artery. Its proximal segment coursed along the common bile duct and lay outside the hepatocystic triangle. The middle segment passed anterior to the cystic duct, whereas the distal segment entered the hepatocystic triangle and reached the gallbladder wall. The artery followed a relatively straight course and measured 4.1 cm in length. Its external diameter was 1.1 mm at its origin and 0.8 mm distally. No accessory cystic arteries, choledochal branches, or additional branches to adjacent structures were identified.

The observed configuration combines an uncommon origin of the cystic artery with a transition from an extratriangular to an intratriangular position and an anterior course relative to the bile ducts. Awareness of this anatomical pattern may aid intraoperative vessel identification, interpretation of angiographic findings, and planning of endovascular procedures.