Case:

54 year old woman presented for open lung biopsy. A CT thorax was obtained which demonstrated an incidental finding of a right vertebral artery arising from the aortic arch distal to the left subclavian artery.

Clinical Significance:

Cases of anomalous origin of the vertebral artery are usually clinically asymptomatic, however, these anatomic variations can play a crucial role in avoiding vascular injury during cerebral angiography, especially with unsuccessful vertebral artery catherization or in the setting of evaluating an intracranial aneurysm. Furthermore, these variations should be considered in preop planning for supraaortic vascular surgeries or ligation of common carotid arteries to avoid compromise of the blood supply to the posterior fossa. These anomalies should also be considered in the setting of a tracheal, esophageal or mediastinal surgery. No Direct correlation has been established between vertebral artery anomalies and Arteriovenous malformation or intracranial aneurysms.