The Anatomic Variations Of Hepatic Arteries And Its Clinical Significance

Objective: The purpose of this study is to investigated the types and frequency of the individual anatomical variations of the hepatic arteries and its importances , to classify anatomic variations of the hepatic arteries and put forward to a new classification of hepatic arterial variations. Material and method: A total of 1000 selective celiac and superior mesenteric or visceral angiographies performed on patients with hepatic diseases were analyzed retrospectively. The origins and branches of the common hepatic artery , proper hepatic artery, left hepatic artery .middle hepatic artery ,and right hepatic artery were observed. We evaluated the types and frequency of anatomical variations of the hepatic arteries . Results: The standard hepatic arterial anatomy was seen in 72.7% and the arterial anatomy was anomalous in 273 out of 1000 cases with an overall incidence of hepatic artery anomalies of 27.3%.148(14.8%) of the cases fitted Michels' classification. Michels â…¡ was seen in 3.3%. Michels â…¢ in 5.3%, Michels â…£ in 1.1% , Michels â…¤ in 1.2%, Michels â…¥ in 1.7%, Michels â…§ in 0.1% and finally Michels â…¨ in 2.1%. There were no Michels â…¦ or â…© variants.However, 125 patients (12.5%) present a lot of types of anatomic arterial variations of the hepatic artery which are not reported in Michels' classification . They are variations of common hepatic arterial furcation in 5.4%, original variations of hepatic arteries in 6.6% .combination of variations of common hepatic arterial furcation with original variations of hepatic arteries in 0.5% and coexistence of multiple anomalies in the celiac-mesenteric arterial system in 2.1%.Variations of common hepatic arterial furcation included the trifurcation of the common hepatic artery to the gastroduodenal and to the right and left hepatic arteries in 4.3%, quardrifurcation of the common hepatic artery to the gastroduodenal and to the right and left hepatic â– arteries and right gastric arteries in 1.0% and the common hepatic artery to the gastroduodenal and to the right .middle and left hepatic arteries and right gastric artery in 0.1%.Regarding the original variations of hepatic arteries, replaced left hepatic arteries arose from the celiac trunk in1.0%, the common hepatic in 1.1%, gastroduodenal artery in 0.1%. Replaced right hepatic arteries arose from the celiac axis in 0.6%, the common hepatic artery in 0.2%, gastroduodenal in 1.1% and splenic artery 0.1%. Replaced middle hepatic arteries arose from the common hepatic artery in 0.1%, gastroduodenal in 0.3% and right renal artery in 0.1%.Accessory right hepatic arteries originated from the celiac axis in 0.1%, the common hepatic artery in 0.3%and gastroduodenal artery in 1.2%.Proper hepatic artery originated from the superior mesenteric artery in 0.1%.Duplicated hepatic arteries originated separately in the celiac trunk in 0.2%. In 0.9% of the cases there was combinations of anomalies of both replaced or accessory right hepatic arteries with replaced or accessory left hepatic arteries .which were not classified by Michels. The combination of the replaced or accessory right hepatic arteries with replaced or accessory left hepatic arteries showed the complex variations of the hepatic arteries. Coclusions: In our series the percentage of hepatic artery variations is in agreement with those reported in the literatures. But the anatomic variations of the hepatic arteries are characterized by a striking degree of polymorphism and complexity . When there is one hepatic arterial variation, there is a high chance of being multiple variations. In combination those reported in the literatures with our study , we put forward to a newer classification of hepatic arterial anatomy which is standard hepatic artery , variation of common hepatic arterial furcation , original variation of hepatic arteries .combination of furcation with original variations of hepatic arteries and coexistence of multiple anomalies in the celiac-mesenteric arterial system. To avoid potentially disastrous complications and increase the rates of success of operations , the recognition of anatomic vascular abnormalities of the hepatic arteries is fundamental to liver transplantation surgeons, generalsurgeons .pretreatment planning for patients requiring hepatic arterial infusion chemotherapy .hepatic arterial infusion pump placement . Realization of this vascular pattern should make identification of the CTA , MRA of hepatic arteries easier for radiologists .