How Far Can we Go? Managing Moyamoya Syndrome in a 3-Year-Old With Thalassemia Major: A Rare Pediatric Case From Nepal.

Moyamoya syndrome (MMS) is a rare progressive cerebrovascular disorder causing stenosis of intracranial arteries and collateral vessel formation. Pediatric presentations often include ischemic strokes, and coexisting Thalassemia Major may worsen vascular outcomes. A 3-year-old male with Thalassemia Major presented with acute right-sided weakness, altered consciousness, and a prior left-sided stroke. Examination revealed facial asymmetry, aphasia, and right-sided hemiparesis. Laboratory tests excluded metabolic, infectious, and cardio-embolic causes. MRI Brain with contrast and TOF-MRA demonstrated chronic right-sided changes, acute left-sided ischemia, and marked narrowing of the supraclinoid and cavernous segments of the left internal carotid artery, confirming Moyamoya disease, Suzuki stage 3. The patient received aspirin (3 mg/kg/day) and supportive care. After 5 days, neurological status improved (GCS 14, right limb power 3/5). Surgical revascularization via EDAS was advised but deferred due to financial constraints. This case highlights alternating hemiparesis as a rare pediatric MMS presentation, the diagnostic utility of MRI/MRA, and the impact of socio-economic limitations on access to definitive surgical care.