Teaching Case

A 42-year-old man underwent a CT of the abdomen for suspicion of acute pancreatitis.

CT revealed an anomalous origin of the right common iliac artery, that arose from the abdominal aorta with a 90° angle at L3 level, and continued its course posterior to the inferior vena cava, between the right psoas muscle and the vertebral body; the external iliac artery course went more deeply into the pelvic cavity compared to the contralateral (Fig. 1, 2). No other vascular anomalies were found.

Vascular malformations involving the iliac arteries are rare, and only a few cases of retropsoas iliac artery are reported in literature [1, 2]. The anomalies in the course and the origin of the iliac artery are usually asymptomatic and discovered incidentally during surgery or radiological investigations. Clinical relevance of this anomaly is related to surgeries in this anatomic area. If not recognized, retropsoas iliac artery can cause haemorrhagic complications in orthopaedic and neurosurgical procedures [3]. Our case demonstrates the role of CT in detecting addition information that may be important for patient care. It is important for the radiologist to also recognize and describe rare anatomical variant.