Inferior Phrenic Arteries and Their Branches, Their Anatomy and Possible Clinical Importance: An Experimental Cadaver Study

Abstract

Surgery is the preferred treatment method for hepatic malignancies. Due to advanced tumor stage and accompanying cirrhosis, most cases are considered inoperable at the time of diagnosis (1). It is well known that the blood supply to liver malignancies is typically arterial, unlike the parenchyma, which is supplied by the portal vein (2). Apart from being the main arterial supply to the diaphragm, the right and left inferior phrenic arteries (RIPA and LIPA), are extrahepatic collateral arterial pathways that supply hepatic malignancies, because they neighbor hepatic segments as they traverse the bare area of the liver (3,4). Among the arterial pathways that supply liver malignancies, both RIPA and LIPA constitute nearly half of the collaterals, with RIPA being the most common and LIPA being the 4th or 6 th most common (5,6). Therefore, both RIPA and LIPA are used during transcatheter arterial chemoembolization of liver malignancies (5-7). Furthermore, LIPA gives branches that supply the stomach and esophagus and can be a source of arterial bleeding at the esophagogastric junction (8)(9)(10)(11)(12).In this study, we aimed to investigate the anatomy of the inferior phrenic arteries -with special reference to the branches of the LIPA -and to outline their clinical importance with anatomical pitfalls which we believe may help interventional radiologists.Background: Transcatheter arterial chemoembolization is a common treatment for patients with inoperable hepatocellular carcinoma. If the carcinoma is advanced or the main arterial supply, the hepatic artery, is occluded, extrahepatic collateral arteries may develop. Both, right and left inferior phrenic arteries (RIPA and LIPA) are the most frequent and important among these collaterals. However, the topographic anatomy of these arteries has not been described in detail in anatomy textbooks, atlases and most previous reports. Aims: To investigate the anatomy and branching patterns of RIPA and LIPA on cadavers and compare our results with the literature. Study Design: Descriptive study. Methods: We bilaterally dissected 24 male and 2 female cadavers aged between 49 and 88 years for this study. Results:The RIPA and LIPA originated as a common trunk in 5 cadavers. The RIPA originated from the abdominal aorta in 13 sides, the renal artery in 2 sides, the coeliac trunk in 1 side and the left gastric artery in 1 side. The LIPA originated from the abdominal aorta in 9 sides and the coeliac trunk in 6 sides. In 6 cadavers, the ascending and posterior branches of the LIPA had different sources of origin. Conclusion: As both the RIPA and LIPA represent the half of all extrahepatic arterial collaterals to hepatocellular carcinomas, their anatomy gains importance not only for anatomists but interventional radiologists as well.

Rare combined variations of renal, suprarenal, phrenic and accessory hepatic arteries

“…The second most frequent type of RIPA origin was found to be the celiac trunk by Kimura et al [14] and Basilie et al [5], the abdominal aorta by Loukas et al [16] and Aslaner et al [4], and the right renal artery by Gürses et al [11]. It is worth mentioning that Kimura et al [14] report the possibility of RIPA originating from the dorsal pancreatic artery, while Aslaner et al [4] note the possibility of it originating from the common hepatic artery.…”

Thoracic Origin of Single Right Renal Artery: Some Interesting Facets

“…Usually, the inferior phrenic artery arises from the abdominal aorta or branches in the following pattern: As a common trunk, from ipsilateral renal, left gastric, common hepatic artery, superior mesenteric, or suprarenal artery. 6 Rarely, it may arise from the celiac trunk. In most patients, RIPA arises as a single trunk from the aorta or right RA.…”

Common and separate origins of the left and right inferior phrenic artery with a review of the literature

“…The RIPA and LIPA can arise separately from the abdominal aorta or from an IPAT [7]. Loukas et al [15] gave an account of their findings concerning various aspects of the IPAs in their dissection of 300 cadavers.…”

“…For instance, the right inferior phrenic artery (RIPA) and left inferior phrenic artery (LIPA) arise separately or from a common trunk [7]. In addition, there are variations wherein the common trunk of the RIPA and LIPA (IPAT) arises from the LGA, abdominal aorta, or CT [1-3, 6, 10, 12, 13, 15, 20-23, 25].…”