Incidence of vertebral artery of aortic arch origin, its level of entry into transverse foramen, length, diameter and clinical significance

Two cases of dual origin left vertebral arteries with non-convergence

“…I n typical human anatomy, the vertebral arteries (VA) originate from the subclavian arteries (SCA), enter the transverse foramen of the sixth cervical vertebra (C6), and travel within the subsequent more superior transverse foramina to enter the skull via the foramen magnum, and provide circulation to the posterior brain. Reported frequencies of VAs with aberrant origins vary widely, and have been reported in anywhere from 5 to 50% of the population [1][2][3]. Of those, left vertebral artery (LVA) variants are most common, appearing in approximately 2 to 7% of the population (as reported in a recent aggregation of studies) [1].…”

“…Reported frequencies of VAs with aberrant origins vary widely, and have been reported in anywhere from 5 to 50% of the population [1][2][3]. Of those, left vertebral artery (LVA) variants are most common, appearing in approximately 2 to 7% of the population (as reported in a recent aggregation of studies) [1]. Approximately 90% of those are part of an atypical aortic arch (AA) branching pattern [3].…”

“…Approximately 90% of those are part of an atypical aortic arch (AA) branching pattern [3]. The clinical significance of a more medial location of these aberrant LVAs [1,[3][4][5][6], in conjunction with their oft-observed more superior entry into the C4 transverse foramen (rather than C6) [7] result in a need to understand their frequency in the population, as well as any co-existing vascular variations. Dual origin VAs are even less common [1].…”

“…The clinical significance of a more medial location of these aberrant LVAs [1,[3][4][5][6], in conjunction with their oft-observed more superior entry into the C4 transverse foramen (rather than C6) [7] result in a need to understand their frequency in the population, as well as any co-existing vascular variations. Dual origin VAs are even less common [1]. They have been reported in less than 50 individuals [1,8] with varying frequency of right side, left side, or bilateral presentations.…”

“…Dual origin VAs are even less common [1]. They have been reported in less than 50 individuals [1,8] with varying frequency of right side, left side, or bilateral presentations. Dual origin VAs present additional clinical concerns, as they have been previously misdiagnosed as a dissection or fenestration of the VA [5].…”