Figure 1. Anatomy of the vertebral artery. C2 represents the second cervical vertebrae, C6 is the sixth cervical vertebrae. V1, V2, V3 and V4 are the anatomic segments of the vertebral artery.

The vertebral-basilar system supplies the brain-stem, cerebellum and temporal and occipital lobes 2 ().It begins as the vertebral artery, which is the first branch of the subclavian artery.

The blood pressure was 85/75 mm. of mercury in the left arm and 120/80 mm. of mercury in the right. There was a localized Grade 2 systolic bruit over the left subclavian artery.