Rare variations of the right hepatic artery and their impact in living donor liver transplantation: a case series.

Understanding the anatomic variations of the hepatic artery is a critical step in planning living donor liver transplantation. Surgical decisions depend on the artery's origin, the number of arteries in the graft, and the presence of intrahepatic communicating arteries. We report a case series of six rare right hepatic artery (RHA) variants identified during preoperative assessment of liver donors: the RHA originated from the common hepatic artery (CHA) with early bifurcation into the right anterior hepatic artery (RAHA) and right posterior hepatic artery (RPHA), with the middle hepatic artery arising from the RAHA; the RAHA originated directly from the aorta and the RPHA from the CHA; the RHA originated directly from the aorta; the RAHA arose from the gastroduodenal artery (GDA) and the RPHA from the superior mesenteric artery (SMA); the RHA arose from the CHA with the segment V artery originating from the GDA; and the RHA originated from the CHA and the segment VI artery from the SMA. These rare RHA variants were thoroughly mapped using preoperative computed tomography angiography. All were successfully utilized as modified right lobe grafts necessitating dual arterial reconstruction except one. Although complex RHA variations with dual arteries present surgical challenges, they can be utilized when their origin provides adequate length and caliber for successful graft anastomosis.