Arc of Buhler: Incidence and Diameter in Asymptomatic Individuals

The purpose of this study was to determine the incidence and diameter of the Arc of Buhler by power injection digital subtraction angiography in asymptomatic patients. A retrospective evaluation of 120 combined celiac (CAx) and superior mesenteric artery (SMA) angiograms was carried out on potential live related liver transplant donors (asymptomatic patients) performed from January 1999 to May 2002. The diameter of the Arc of Buhler was calculated with reference to the 5 French catheters used to perform the diagnostic angiograms. It was considered hemodynamically significant if it preferential filled the branches of the other visceral vessel. An Arc of Buhler was identified in 4 patients (3.3%). All 4 patients had a patent gastroduodenal artery (GDA) and none of the 4 had a hemodynamically significant stenosis of either the SMA or the CAx. All Arcs of Buhler found measured less than 2.5 mm in diameter and half of them (2 of the 4) filled the CAx when power injecting the SMA and/or vice versa. There is a low incidence of Arc of Buhler in asymptomatic patients; however, 50% of those encountered were hemodynamically significant. When evaluating the Arc of Buhler by angiography in the setting of pathology, it is important to have a reference diameter and hemodynamic reference in the normal setting, particularly when the prospect of GDA ligation or embolization is entertained in the presence of CAx or SMA occlusion.