Bifurcated Arc of Buhler Co-existent with an Arc of Riolan-A Rare Case Report

Abstract

The Arcs of Buhler and Riolan are collateral channels that connect the major midline ventral branches of the abdominal aorta, which supply the gastrointestinal tract. These arcs occur with a relative rarity of 1-10%. During routine dissection of the abdominal cavity of a 50-year-old, embalmed male Indian cadaver in the Department of Anatomy of a National Institute in South India, the presence of a large vertical tortuous bifurcated artery was noticed, posterior to the body of the pancreas, connecting the coeliac trunk to the superior mesenteric artery. This was identified to be an Arc of Buhler (AOB) and measuring 8 mm in external diameter. In addition, an Arc of Riolan (AOR) was identified, connecting the left division of the Buhler’s arc to the left colic artery. The presence of a large bifurcated AOB or its co-existence with an AOR has not been described previously. The identification of such anastomotic channels in symptomatic patients may help in diagnosing impending bowel ischemia. Aneurysms of AOB, though rare, are life-threatening and have been treated successfully. The knowledge of mesenteric vascular anatomy is important during abdominal surgeries and endovascular procedures. Recognising a vascular variation is crucial to avoid inadvertent bleeding or bowel ischaemia.