Accessory right hepatic artery and aberrant bile duct in the hepatocystic triangle: a rare case with clinical implications

Awareness of variations in the hepatic vasculature and biliary system is extremely important for avoiding iatrogenic injury in upper-abdominal surgery. The objective of this study is to describe a rare case of abnormal vascular and biliary structures in the hepatocystic triangle (HCT) (the modern Calot's triangle). During anatomical dissection of the celiac trunk (CT) in an old man, the authors observed the presence of a hepatosplenic trunk arising from the CT and bifurcating into common hepatic and splenic arteries. The common hepatic artery divided into hepatic artery proper and gastroduodenal artery. The presence of accessory right hepatic artery (ARHA) arising from the superior mesenteric artery was also notable. The aberrant artery ascended retropancreatically ventral to the splenic vein, then posterolaterally to the portal vein before termination into the right hepatic lobe in the HCT. Within this triangle, there was an aberrant bile duct originating in the right hepatic lobe and ending in the common hepatic duct. This accessory duct crossed the ARHA and an associated branch (the cystic artery). There is no known previous report on the co-existence of an AHAR and an aberrant bile duct within the HCT, in addition to the hepatosplenic trunk. The clinical implications of the current case are addressed in discussion.

Unusual development of the celiac trunk and its clinical significance

We describe a case of unusual development of the celiac trunk observed in the cadaver of 1-year old male child. The celiac trunk branched into five vessels: the splenic, common hepatic and left gastric arteries, the left inferior diaphragmatic artery, and a short trunk that branched into the right inferior diaphragmatic artery and right accessory hepatic artery. Additionally, the manner of branching of the vessel was unusual: it was possible to distinguish two branching points that corresponded to its s-shaped trajectory. There were also other variations of vascular supply, such as the presence of a left accessory hepatic artery, an additional superior pancreatoduodenal artery, and others. It should be noted that multiple developmental variations can be common in clinical practice and clinicians should be aware of them during diagnostic and interventional procedures.

Rare anatomic variation of the right hepatic artery and accessory right hepatic artery supplying hepatocellular carcinoma: A case report and literature review

INTRODUCTION

Each hepatic artery is functionally essential for providing blood supply to the liver, and so are variant arteries. Variant arteries, including the accessory right hepatic artery (ARHA) and replaced right hepatic artery (RRHA) are commonly described in the literature. However, they usually occur independently. Here, we report an extremely rare case that involved both an ARHA and an RRHA arising from the gastroduodenal artery (GDA) and superior mesenteric artery (SMA), respectively. To date, this situation has never been reported in the literature.They were preoperatively identified during magnetic resonance imaging (MRI) examination in a 69-year-old male patient with hepatocellular carcinoma. And they were further verified by following conventional angiography for transcatheter arterial chemoembolization (TACE) for the patient. In addition, the patient's tumor was primarily supplied by these 2 variant arteries. After the successful TACE procedure, the patient had a well postoperative recovery.

CONCLUSIONS

By analyzing this case and performing a systematic review of the literature, the important clinical implications of the ARHA and RRHA will be investigated and discussed. Main lessons learned from this case thorough understanding of the normal anatomy of the hepatic artery and its anatomic variation is crucial for surgeons and interventional radiologists; preoperative computed tomography, MRI, and intraoperative angiography play an important role in detecting the variant hepatic artery; identifying these anomalous hepatic arteries before operation can effectively avoid unintentional injury during surgery, such as massive hemorrhage or hepatic infarction.

Anatomical variant of the liver blood supply

Vascular variations are significant for liver transplantations, radiological procedures, laparoscopic method of operation and for the healing of penetrating injuries, including the space close to the hepatic area. These variants are very common in the abdominal region, and their description will be useful. During a routine dissection of a 73 year old female cadaver, we found in the subhepatic region that the blood supply of the liver differed from a normal one. The difference was found in the absence of the right liver branch and the cystic artery, which normally arises from the common hepatic artery. After a detailed dissection of the superior mesenteric artery we distinguished a branchthat was routed to the right lobe of the liver. The diameter of this vessel was 3.7 mm and the length 8.2 cm. In the artery pathway, three consecutive branches were observed. The first branch was found about 2.02 cm before the portal region of the liver. The second one became visible after another millimeter and finally the artery made one little curve and became a cystic artery.