Anomalous origin and cervical course of the vertebral artery in the presence of a retroesophageal right subclavian artery

Abstract

The vertebral artery is usually described as the first branch of the subclavian artery, originating medial to the scalenus anterior muscle. During its cervical course, the vertebral artery presents a prevertebral segment and then enters the foramen transversarium of the sixth cervical vertebra. We describe a case of an unusual origin and course of the right vertebral artery in a cadaver specimen wherein the right vertebral artery originates from the right common carotid artery at the inferior border of the thyroid gland. In its cervical course the vertebral artery ascends outside and anteriorly to the foramen transversarium of vertebrae C VI to C III, and enters the foramen transversarium of the axis. In the same specimen, a retroesophageal right subclavian artery is also present. These vascular abnormalities are presented for physicians to keep in mind such variations during diagnostic investigation and surgical procedures of the neck.

Vertebral artery anomaly with entry at C4—avoiding a surgical pitfall: a case report

“…Variations of the pretransverse segment of the VA have been described extensively, concerning origin [1,2,11,13], tortuosity in its course [6,11,15] and entry in the transverse foramen [1,5,7,9,11]. Entry in the transverse foramen varies from C7 up to C2 [5,7,9]. Although the lateral position of VA does not hinder the anterior approach and therefore vertebral artery injury (VAI) in anterior cervical spine surgery is a rare complication with incidences of 0.3-0.5% [14], it might be an underestimated problem [8].…”

“…Most commonly vertebral arteries arise from the superoposterior aspect of the first part of subclavian artery and than take a posterior cephalad course to enter the transverse foramen at C6, but other entry levels have been described. Anomalies have been reported with an entry level of C2 [5] and C3 [7,9]. The entry of the VA into the transverse foramen at C4 has been seen in anatomical studies with an incidence of 1-1,4% [1,11].…”

Bicuspid aortic valve and lusory artery: an unusual association

“…Lusory artery is an uncommon congenital vascular abnormality, whose incidence varies between 0.2-2.5 % [1], resulting from interruption of the fourth right aortic arch between the common carotid artery and subclavian artery and the persistence of the retroesophageal aortic arch [2]. The right subclavian artery thus originates as the last branch of the aortic arch.…”

“…The right subclavian artery thus originates as the last branch of the aortic arch. The condition is usually asymptomatic, even if it may cause dysphagia due to esophageal compression [1]. Complications are described, ranging from atherosclerotic disease and thrombosis [3], potentially eased by the abnormal retroesophageal course, to aneurysma [4] and arterioesophageal fistulae, and other possible serious events usually precipitated by the placement of nasogastric tubes in patients where the erosion of the esophagus was already present [5].…”

“…Complications are described, ranging from atherosclerotic disease and thrombosis [3], potentially eased by the abnormal retroesophageal course, to aneurysma [4] and arterioesophageal fistulae, and other possible serious events usually precipitated by the placement of nasogastric tubes in patients where the erosion of the esophagus was already present [5]. Despite the potentially dangerous implications, this anatomical variant does not usually require surgery, although restoring a normal course of the right subclavian artery by aortic arch repair is feasible and often recommended [1].…”