Early-onset Moyamoya disease presenting with recurrent seizures and dysphagia in a 3.5-year-old child: a case report

Abstract Moyamoya disease is a rare, progressive cerebrovascular disorder characterized by stenosis or occlusion of the terminal internal carotid arteries and the formation of abnormal collateral vessels at the base of the brain. Pediatric patients commonly present with ischemic manifestations including seizures, transient ischemic attacks, or stroke, and early diagnosis is essential to prevent progressive neurological impairment. A 3.5-year-old girl presented with dysphagia and global aphasia following a prolonged generalized tonic-clonic seizure, with a history of two prior seizure episodes over the preceding year. Neurological examination revealed right-sided motor weakness with hyperreflexia and an extensor plantar response. Initial neuroimaging following the first seizure had demonstrated focal cerebral atrophy and gliosis consistent with an old infarct. Subsequent magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) revealed severe attenuation of the intracranial internal carotid arteries and major cerebral branches with basal collateral vessel formation, establishing a diagnosis of Moyamoya disease (Suzuki grade II–III). The patient was commenced on antiplatelet therapy and anticonvulsants, and referred for digital subtraction angiography and neurosurgical evaluation for possible revascularization. Moyamoya disease should be considered in young children presenting with recurrent seizures and focal neurological deficits. Early neurovascular imaging with MRI and MRA is critical for establishing the diagnosis and facilitating timely referral for definitive surgical management. Prompt recognition and intervention are essential to prevent recurrent ischemic events and optimize long-term neurological outcomes.