Surgical Neurology 67 (2007) 174 – 176
www.surgicalneurology-online.com

Vascular

Bilateral aortic origins of the vertebral arteries with right vertebral artery
arising distal to left subclavian artery: case report
Riyadh Al-Okaili, MB, BS, Eric D. Schwartz, MD4
Department of Radiology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA
Received 9 February 2006; accepted 21 February 2006

Abstract

Background: Bilateral aortic origins of the vertebral arteries are a rare anatomic variant, with fewer
than 20 cases reported in the literature. This particular variant has only been reported twice.
Case Description: A 35-year-old woman presented to the emergency department after trauma to the
head and a witnessed convulsion. Subsequent workup included MRI/MRA, which resulted in
identification of the anomaly.
Conclusion: The clinical importance of aortic arch anomalies lies in that it may be a source of
misinterpretation, as one may conclude occlusion of the vertebral artery if the aberrant origin is not
included in the MRA or CTA imaging parameters. Therefore, it is important to scan through the
entire aortic arch to just below the level of the ligamentum arteriosum when performing these
noninvasive modalities. In addition, vertebral arteries arising from the aortic arch have an increased
risk of dissection.
D 2007 Elsevier Inc. All rights reserved.

Keywords:

Vertebral artery; MRI; MRA; Congenital vascular anomaly

1. Introduction
Although aortic origin of the LVA is an anatomic variant
with a prevalence of 2.4% to 5.8% [5], an aortic origin of
the RVA is much less common with fewer than 20 cases
reported in the literature [1-3,5-10]. Bilateral origins of the
vertebral artery are rarer with less than 10 cases reported in
the literature [2,3,5,7]. We report an even rarer aberration
with the RVA arising from the descending aortic arch distal
to the left subclavian artery and the LVA arising from
between the left common carotid and left subclavian
arteries. There have only been 2 other reports of this
anomaly with this one being the first to identify the variant
with MRA [3,7].

Abbreviations: BT, Brachiocephalic trunk; CTA, Computed tomography angiography; LCCA, Left common carotid artery; LSCA, Left
subclavian artery; LVA, Left vertebral artery; MIP, Maximum intensity
projection; MRA, Magnetic resonance angiography; MRI, Magnetic
resonance imaging; RVA, Right vertebral artery.
4 Corresponding author. Tel.: +1 215 662 3010; fax: +1 215 662 3283.
E-mail address: eric.schwartz@uphs.upenn.edu (E.D. Schwartz).
0090-3019/$ – see front matter D 2007 Elsevier Inc. All rights reserved.
doi:10.1016/j.surneu.2006.02.045

Fig. 1. Surface rendering from 3-D gadolinium-enhanced MRA shows 5
vessels arising from the aortic arch, in the following order: BT, LCCA,
LVA, LSCA, RVA.

R. Al-Okaili, E.D. Schwartz / Surgical Neurology 67 (2007) 174 – 176

2. Case report
2.1. Clinical presentation
A 35-year-old woman presented to the emergency
department after falling from a bicycle which was followed
by a witnessed convulsive episode. Her physical examination was remarkable for forehead abrasions but was
otherwise normal. Her workup for suspected seizure
disorder included MRA of the neck which was performed
on a 1.5-T MRI scanner and included 2-dimensional (2-D)
time of flight and 3-D gadolinium-enhanced MRA. Postprocessing was performed using Vitrea 2 software (Vital
Images, Minnetonka, Minn).
2.2. Radiographic findings
The study showed that both vertebral arteries arose
directly from the aortic arch. Five trunks in total originated
from the aortic arch with the following order from right to
left: BT, LCCA, LVA, LSCA, and RVA as the last branch
(Figs. 1 and 2). The BT, LCCA, and LSCA were otherwise
normal. The LVA entered the left fourth transverse foramen,
which is expected for LVAs that arise directly from the aorta
[7]. The RVA coursed posterior to the esophagus and
entered the right seventh transverse foramen. No other
abnormalities such as vertebral dissection, stenosis, or
aneursymal dilatations were seen in the arterial vasculature.

175

The aortic arch was remarkable for an area of mild
narrowing at the level of the ligament arteriosum consistent
with aortic pseudocoarctation. The patient did not have
secondary signs of a hemodynamically significant coarctation such as upper extremity hypertension or blunting of the
dorsalis pedis pulses. Normal upper extremity blood
pressure measurements (blood pressure of 119/74) were
recorded, and both dorsalis pedis pulses were detectable and
comparable in strength to the radial pulses. In addition,
MRA did not show formation of collateral circulation.

3. Discussion
Bilateral origins of the vertebral artery are rare, and the
particular branching pattern seen in this case has only been
described twice, once in a cadaver and once with a CTA
[3,7]. Also noted in this case was an infundibulum, or
diverticulum, at the anomalous origin of the RVA similar to
previous reports [3,7]; however, the presence of pseudocoarctation was not described previously.
The clinical importance of such anomalies lies in that it
may be a source of misinterpretation, as one may conclude
occlusion of the vertebral artery if the aberrant origin is
not included in the MRA or CTA imaging parameters.
Therefore, it is critical to scan through the entire aortic
arch to the level of the ligamentum arteriosum when
performing these noninvasive modalities. Vertebral arteries
of aortic origin have also been shown to be associated
with increased predilection for dissection in comparison
to those of subclavian artery origin [4]. Identification of
these anomalies is also important for angiographic or
surgical planning.

References

Fig. 2. Maximum intensity projection image obtained with 3-D gadoliniumenhanced MRA shows the origin of the right vertebral artery off
the descending aorta (white arrow). Note the slight narrowing of the
aorta before the takeoff of the right vertebral artery consistent with
a pseudocoarctation.

[1] Albayram S, Gailloud P, Wasserman BA. Bilateral arch origin of the
vertebral arteries. Am J Neuroradiol 2002;23(3):455 - 8.
[2] Goray VB, Joshi AR, Garg A, et al. Aortic arch variation: a unique
case with anomalous origin of both vertebral arteries as additional
branches of the aortic arch distal to left subclavian artery. Am J
Neuroradiol 2005;26(1):93 - 5.
[3] Karcaaltincaba M, Strottman J, Washington L. Multidetector-row CT
angiographic findings in the bilateral aortic arch origin of the vertebral
arteries. Am J Neuroradiol 2003;24(1):157.
[4] Komiyama M, Morikawa T, Nakajima H, et al. High incidence of
arterial dissection associated with left vertebral artery of aortic origin.
Neurol Med Chir (Tokyo) 2001;41(1):8 - 11 [discussion 11-2].
[5] Lemke AJ, Benndorf G, Liebig T, et al. Anomalous origin of the right
vertebral artery: review of the literature and case report of right
vertebral artery origin distal to the left subclavian artery. Am J
Neuroradiol 1999;20(7):1318 - 21.
[6] Sakamoto H. A case of the right vertebral artery as the last branch of
the aortic arch. Kaibogaku Zasshi 1980;55(5):503 - 8.
[7] Schwarzacher SW, Krammer EB. Complex anomalies of the human
aortic arch system: unique case with both vertebral arteries as
additional branches of the aortic arch. Anat Rec 1989;225(3):246 - 50.
[8] Stoesslein F, Porstmann W, Schueler F, et al. Aberrant vertebral artery
originating from the descending aorta: a new congenital steal
syndrome in coarctation. Eur J Radiol 1982;2(2):157 - 9.

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R. Al-Okaili, E.D. Schwartz / Surgical Neurology 67 (2007) 174 – 176

[9] Takagi T, Yamashita K. Right vertebral artery as the last branch of the
aortic arch and a coronary sinus opening into the left atrium as found
in a cadaver. Kaibogaku Zasshi 1992;67(1):49 - 52.
[10] Wasserman BA, Mikulis DJ, Manzione JV. Origin of the right
vertebral artery from the left side of the aortic arch proximal to the
origin of the left subclavian artery. Am J Neuroradiol 1992;13(1):
355 - 8.

Commentary
The authors report an excellent demonstration of bilateral
origin of both vertebral arteries from the aortic arch. One

can imagine the difficulty in finding the origin of these
arteries during an angiogram if we did not have MRA.
Gerard Debrun, MD
Interventional Neuroradiologist
Paris, 29360 France