Abstract

Reversible vertebral artery syndrome (RVAS) is characterized by recurrent attacks of vertigo, nystagmus, and syncope induced by compression of the vertebral artery during head rotation. A 60-year old man with atlas vertebrae fracture. presented recurrent attacks of positional vertigo. Left-beat, upbeat and count clock-wise torsional nystagmus occurred after lying down and bilateral head roll (HR) showing no latency or fatigue. MRI revealed foramen magnum stenosis (FMS) and dominancy of right vertebral artery (VA). The flow of the right VA on trans-cranial Doppler decreased significantly during left HR. The slower the velocity was, the more the nystagmus was aggravated. RVAS can be evoked by FMS causing compression of the VA. And the nystagmus might be aggravated according to the blood flow insufficiency.

• Keywords: Rotational vertebral artery compression; Foramen magnum stenosis; Central Positional Nystagmus;