A Rare Coeliacomesenteric Trunk Arising from the Aorta and a Hepatophrenic Trunk Giving Rise to an Accessory Left Hepatic Artery: Proposal of a New Classification System for Hepatic Arterial Variations

Abstract Accurate knowledge of hepatic arterial variation is essential for both surgical planning and interventional radiology. Although numerous classification systems describe these variations, exceptionally rare configurations continue to challenge existing models. This report presents an unusual vascular pattern in which an accessory left hepatic artery originates as a single trunk from both the celiacomesenteric trunk (CMT) and the aorta, accompanied by an inferior phrenic artery forming a hepato-phrenic trunk (HPT). Based on this case, we propose an alternative key intended to enhance current hepatic artery classification systems. A 79-year-old Turkish male undergoing evaluation for hypertension was found to have an atypical hepatic arterial pattern on abdominal computed tomography (CT). Three-dimensional reconstruction using the Vitrea software enabled precise assessment of vessel dimensions and spatial relationships. Imaging revealed the simultaneous presence of a CMT and a HPT. The CMT directly originated the proper hepatic artery (PHA) without a common hepatic artery (CHA). The PHA then bifurcated into the right hepatic artery (RHA) and left hepatic artery (LHA), while the gastroduodenal artery (GDA) arose distal to it. Separately, the HPT emerged from the aorta and divided into the accessory left hepatic artery (aLHA) and the inferior phrenic artery (IPA). Comparison with previously reported cases highlights the exceptional nature of this combined variation. Rather than adapting it within current systems, we introduce a new hepatic artery variation key derived from this configuration, offering a more flexible framework for future anatomical and clinical applications.