We report a patient who suffered drop attacks during head reclination. Computer tomography of the cervical spine demonstrated a stenotic right vertebral artery at C4/5. However, Doppler ultrasonography of the vertebral artery showed no abnormality. Angiography confirmed complete occlusion of the left vertebral and a stenosis of the right vertebral artery. Dynamic angiography indicated occlusion of the stenotic region on the right side during reclination of the head. Surgery using a posterior approach with decompression of the vertebral artery, lead to an excellent outcome and the patient left the hospital without any symptoms. Therefore, in patients with drop attacks and normal ultrasonography, a stenosis of the vertebral artery caused by a spondylophytic compression could still be the cause. At worst, the stenosis could lead to brain infarction if left untreated. Dynamic angiography is crucial for the diagnosis and surgical decompression has excellent results.