Unilateral Upper Cervical Posterior Spinal Cord Infarction Caused by Spontaneous Bilateral Vertebral Artery Dissection

A 41-year-old woman complained of sudden numbness of the left face and limbs without neck pain, paraparesis, urinary retention, or constipation. Neurologic examination revealed onion-skin pattern hemifacial dysesthesia and disturbance of touch and proprioception sensation of the left limbs. T2WI and Diffusion weighted imaging (DWI) showed left posterior spinal cord infarction at the C1 level (Figure, A–D). Magnetic resonance angiography (MRA) demonstrated stenosis of bilateral vertebral arteries (Figure, E–F). High-resolution MRI revealed the high signals of intramural hematoma in bilateral vertebral arteries indicating the diagnosis of dissection (Figure, G-J). Isolated posterior spinal cord infarction is rare, and vertebral artery dissection should be considered as an etiologic mechanism.1