The vertebral artery segments

3D Model

A computed tomography angiography (CTA) based 3D model presenting the segments of the vertebral artery. The vertebral artery (VA) is traditionally divided into four segments. The V1 segment (ostial or proximal segment) projects from the subclavian artery to the transverse foramen of C6. The V2 segment (vertical segment or transversary) courses the transverse foramina between C6 to C2. The V3 segment (suboccipital segment) extends from the transverse foramen of C2 to the dura at the foramen magnum. This is the mobile segment of the VA and may be further divided into a vertical portion between the C1-C2 transverse processes, a horizontal portion on the C1 sulcus and an oblique portion between the C1 sulcus and dura mater 1. The final, V4 (intradural or intracranial) segment is running anteriorly to the caudal group cranial nerves (IX, X, XI) and joins the contralateral V4 segment giving rise to the basilar artery at the ponto-medullary junction