Vertebrobasilar Insufficiency Caused by Lateral Head Tilting

Vertebrobasilar insufficiency (VBI) in rotatory vertebral artery occlusion syndrome can be caused by voluntary head turning in the yaw plane. We report a case of VBI for head tilting in the roll plane. Transcranial Doppler on left head tilting resulted in decreased blood flow in both vertebral arteries. A CT angiogram revealed that the stenotic left vertebral artery was very close to an enlarged thyroid gland, suggesting mechanical compression of the vertebral artery during head tilt.