Moyamoya Disease Presenting as a Transient Ischemic Attack Following Recurrent Intracerebral and Intraventricular Hemorrhage

Moyamoya disease (MMD) is a rare, progressive cerebrovascular disorder characterized by stenosis of the internal carotid arteries and their branches, with compensatory development of abnormal, fragile collateral vessels at the base of the brain. It has a bimodal age distribution, is more prevalent in females, and typically manifests as cerebral ischemia or hemorrhage with a progressive clinical course. The co-occurrence of recurrent hemorrhagic events followed by transient ischemic episodes within the same disease course represents a particularly uncommon and diagnostically challenging clinical presentation. We report a 45-year-old female with a prior history of intracerebral hemorrhage with intraventricular extension, who recovered without residual neurological deficits. The patient subsequently presented to the Emergency Department via Emergency Medical Service with a several-day history of severe headache, dizziness, and arterial hypertension, with symptom intensification in the hours preceding admission. Notably, the patient reported transient weakness of the right upper limb accompanied by brief speech disturbance prior to hospital arrival, which resolved completely within 24 hours. On arrival, blood pressure was 154/90 mmHg, and neurological examination revealed a Glasgow Coma Scale (GCS) of 15 (E4V5M6), intact orientation and speech, full motor strength in all four extremities, symmetric reflexes, no pathological signs, and no meningeal irritation, consistent with a transient ischemic attack (TIA) without persistent neurological deficit. Cerebral CT angiography excluded acute intracranial pathology but identified a markedly atypical vascular pattern: reduced trunk-type contrast filling in the anterior circulation with compensatory collateral hemodynamic circulation, highly suggestive of MMD. Digital subtraction angiography (DSA) and neurosurgical consultation were recommended for definitive vascular characterization. The patient was managed with symptomatic treatment and dynamic monitoring, demonstrated clinical improvement with hemodynamic stabilization, and was discharged with appropriate recommendations. This case underscores the complex and heterogeneous clinical spectrum of MMD, in which a patient may experience recurrent hemorrhagic events followed by ischemic manifestations such as TIA within the same disease course. The diagnosis was established non-invasively through CT angiography, which revealed a characteristic collateral vascular pattern in the absence of acute pathology. Clinicians should maintain a high index of suspicion for MMD in patients presenting with mixed cerebrovascular events, as early recognition and prompt referral for advanced vascular imaging and neurosurgical evaluation are critical for optimizing long-term outcomes.