A Case of Duplicated Origin of the Left Vertebral Artery: CTA and MRA Findings and Literature Review

Abstract

Duplication of the vertebral artery (VA) is rare but clinically significant. This variant shows a dual origin of VA with fusion at variable levels in the neck. It can be misdiagnosed as a dissection of the VA, arterial hypoplasia, or narrowing on selective catheter angiography. Thorough knowledge of this variation before an endovascular procedure is helpful in preventing unintentional diagnostic or therapeutic challenges. We report a case of a 52-year-old female patient with left duplicated VA, which was incidentally detected by magnetic resonance angiography (MRA) and contrast-enhanced computed tomography angiography (CTA). We have also reviewed the literature and discussed the embryological development of duplicated VA. This report can be helpful in identifying unexpected vascular variations on CTA or MRA and differentiate this anatomical variation from other pathologic conditions in clinical practice such as dissection, arterial hypoplasia, or arterial narrowing.

Retrospective Study of Normal Variations in Vertebral Artery on CT angiography with special emphasis on relevant embryology

“…Embryological events which can lead to persistence of a particular intersegmental artery decide the level at which the VA originating from aorta will enter the respective FT in adult life. (23). Abnormal entry into the FT was found to be as high as 2.2% on the right sided C4 and 6.5% on the left sided C5.…”

“…Duplication in the origin of the left VA is rare and refers to VA with two origins that fuse at various levels. (18,20,21,22,23) The persistence of the embryological intersegmental arteries along with the normal subclavian origin can lead to such con gurations. (Schematic represented in Figure 2) This aortic origin may produce greater shear stress when compared to that of normally arising subclavian VA, as it receives a direct pulsatile blood ow compared to the dampening effect created in the latter.…”

Retrospective Study of Normal Variations in Vertebral Artery on Computed Tomography Angiography With Special Emphasis on Relevant Embryology

“…This whole arrangement presented as a dual origin of VA on the left side. Duplication in the origin of the left VA is rare and refers to VA with two origins that fuse at various levels [17,[19][20][21][22]. The persistence of the embryological intersegmental arteries, along with the normal subclavian origin, can lead to such configurations (Figure 2).…”

“…Hong JM et al Embryological events which can lead to the persistence of a particular intersegmental artery decide the level at which the VA originating from the aorta will enter the respective FT in adult life [22]. Abnormal entry into the FT was found to be as high as 2.2% on the right-sided 4th cervical vertebra and 6.5% on the left-sided 5th cervical vertebra.…”