Anomalous origin of both vertebral arteries

The authors describe a case of an unusual origin of both vertebral arteries in a singular cadaver. On the left, the artery arises directly from the co mmon trunk of vertebral and subclavian artery at the aortic arch and enters the transverse cervical foramina at C VI. On the right, the artery origina tes from the right common carotid artery and enters the transverse foramina at C III. Additional anomalies were observed on the aortic arch: the commo n trunk of both common carotid arteries, the common trunk of the left verte bral and subclavian artery, and as a last branch, the retroesophageal right subclavian artery. The morphometric measurements of the vertebral arteries were performed. The literature on the variations of the vertebral arteries is reviewed and their clinical importance for diagnostical procedures and head and neck surgery stressed. (C) 1999 Wiley-Liss, Inc.