Bilateral cerebellar, left lateral medulla, and spinal cord infraction caused by idiopathic dissection of left subclavian artery

We report a case of bilateral cerebellar, left lateral medulla, and spinal cord infarction in a 69-year-old man with sudden headache. He reported speech disturbance and left motor weakness 11 hours after the onset of the headache. MRI showed acute bilateral cerebellar and left lateral medullary infarctions. On the 2nd day of admission, right hemiparesis occurred and progressed to quadriplegia. Magnetic resonance imaging of the cervical spine showed a spinal cord infarction in the regions of C2 to C5. 1st DSA revealed an almost complete occlusion from the origin of the left subclavian artery to the bifurcation of the left vertebral artery. No anterior spinal artery was recognized, even from the right vertebral artery. 2nd DSA on the 30th day of admission showed improvement of severe stenosis of the left subclavian artery. An ultrasound scan of the subclavian artery revealed a flap structure on the left side. We suspected that it was caused by arterial dissection due to the sequential morphological change and recanalization of the artery. We recommend to check the morphological changes in the vessels using several modalities, because severe stenosis of the subclavian artery is sometimes caused by arterial dissection. Ultrasound of the artery may help to identify the dissection.