Clinical anatomy of the inferior phrenic artery

The majority of anatomical textbooks of gross anatomy offer very little information concerning the anatomy and distribution of the inferior phrenic artery (IPA). In the last decade, however, increased numbers of reports have appeared with reference to the arterial supply of hepatocellular carcinoma (HCC). The IPA is a major source of collateral or parasitized arterial supply to this type of carcinoma, second only to the hepatic artery. The aim of this study was to identify the origin and distribution of the IPA (right and left), in normal and pathological cases, and to apply such findings to the clinical scenario of treating hepatic cancer. We have examined 300 formalin-fixed adult cadavers lacking abdominal pathology, and 30 cadavers derived from patients with HCC. Dissections in normal cadavers showed that the right IPA originated from the: a) celiac trunk in 40% of the specimens; b) aorta in 38%; c) renal in 17%; d) left gastric in 3%; and e) hepatic artery proper in 2% of the specimens. The left IPA originated from the: a) celiac trunk in 47%; b) aorta in 45%; c) renal in 5%; d) left gastric in 2%; and e) hepatic artery proper in 1% of the specimens. The IPA gave rise to eight notable branches: ascending, descending, inferior vena cava, superior suprarenal, middle suprarenal, esophageal, diaphragmatic hiatal, and accessory splenic. The right IPA was always associated with HCC and served as the major collateral artery adjunct to the hepatic artery. These findings could have major implications in the transcatheter embolization of HCC patients.