Man in mid-sixties presenting with dizziness and “closing curtains” on his vision when turning head to extreme left or right (left worse than right). CTA demonstrates hypertrophy of the left C4 facet (blue), encroaching upon the vertebral foramen (purple). The contralateral vert is hypoplastic (yellow)
Volume rendered images demonstrating facet hypertrophy and, on the right, cutaway with vertebral foraminal narrowing
Frontal and frontal oblique projection angiography confirming vertebral artery impingement during rotation to the left
Mainstay of treatment is surgical mobilization of the vertebral artery.