Hemiplegic Migraine and Moyamoya Disease

Sir.—Hemiplegic migraine is a form of complicated migraine.¹In children, such migraine without headache often manifests initially as transient hemiplegia,^2,3and the symptoms may be indistinguishable from those of transient ischemic attacks (TIAs). Moyamoya disease is a rare vasculopathy of the intracranial portion of the carotid and vertebral arteries⁴and is of unknown origin. Moyamoya disease occurs in children and young adults and causes occlusion of the major cerebral vessels.^5-8Initial signs are usually strokes, seizures, or TIAs.⁹After a major neurologic event, cerebral angiography is often used to diagnose moyamoya disease. Moyamoya ("puff of smoke" in Japanese) disease was previously identified from angiograms showing telangiectatic vessels acting as collateral channels to the occluded distal carotid arteries.¹⁰More recently, magnetic resonance imaging (MRI) has been used to identify the abnormal occluded vessels as well as the dilated collateral vessels in the basal ganglia