Celiac Axis and Common Hepatic Artery Variations in 5002 Patients: Systematic Analysis with Spiral CT and DSA

Purpose: To identify and evaluate the spectrum and prevalence of celiac axis (CA) and common hepatic artery (CHA) variations by using spiral computed tomography (CT) and digital subtraction angiography (DSA). Materials and Methods: Institutional review board approval was obtained, and the requirement for informed patient consent was waived. The findings in 5002 patients who underwent spiral CT and DSA were retrospectively evaluated. CHA was defined as an arterial trunk containing at least one segmental hepatic artery and the gastroduodenal artery. The pattern of the aortic origin of the branches of the CA and superior mesenteric arteries was analyzed. The CHA anatomy was then investigated. Results: Of 15 possible types of CA variation, 13 types were identified. A normal CA was noted in 4457 (89.1%) of the 5002 patients. Twelve types of CA variation were identified in 482 (9.64%) patients. In the remaining 63 (1.26%) patients, the CA anatomy was classified as ambiguous because the CHA was absent owing to separate origins of the hepatic arteries and the gastroduodenal artery (n = 55) or because the origin of the CHA could not be determined owing to persistent anastomotic channels (n = 8). Seven CHAs originating from the normal CA had a retroportal (n = 6) or transpancreatic (n = 1) course. All eight CHAs originating from the left gastric artery passed the fissure of the ligamentum venosum. The 148 CHAs originating from the superior mesenteric artery showed diverse relationships with the pancreas-being supra-, trans-, or infrapancreatic-and the superior mesenteric-portal venous axis-being pre-or retroportal. The 20 CHAs originating from the aorta had a normal suprapancreatic preportal course. Conclusion: Known or newly found CA and CHA variations could be systematically described in detail. The authors propose a hypothetical anatomic model for summarizing the observed CHA variations. (C) RSNA, 2010