Variation of the Gallbladder Vasculature Double Cystic Arteries

Instead of the "classic" single cystic artery, arising usually from the right hepatic artery, occasionally two distinct cystic arteries supplying the gallbladder. This duplication can manifest in several ways. Both arteries may originate from the right hepatic, branching separately to reach the gallbladder, sometimes referred to as "parallel" cystic arteries. Another variation involves one cystic artery arising from the right hepatic and the second from a different source, such as the gastroduodenal artery, the common hepatic artery, or even, albeit rarely, the superior mesenteric artery. The point of entry into the gallbladder itself can also vary; both might enter the Calot's triangle, or one may enter directly into the gallbladder body, avoiding the triangle altogether. The clinical significance of this anatomical variation is primarily surgical. During cholecystectomy, particularly laparoscopic cholecystectomy, failure to identify and adequately ligate both cystic arteries can lead to troublesome bleeding, potential bile duct injury due to misidentification of structures amidst the hemorrhage, and even conversion to an open procedure. Pre-operative imaging, such as CT angiography or MR angiography, can sometimes identify double cystic arteries, allowing the surgeon to plan accordingly. However, these imaging modalities are not always definitive, and intraoperative awareness and meticulous dissection remain crucial for a safe and successful cholecystectomy in patients with this anatomical variation. A thorough understanding of these variations and their potential presentation is paramount for any surgeon performing gallbladder surgery.