Radiation-induced Moyamoya syndrome—missed diagnosis with a fatal outcome in a recurrent craniopharyngioma

Secondary Moyamoya syndrome (MMS) is a rare but serious complication of radiotherapy (RT) in patients with craniopharyngiomas. This report details the fatal clinical course in a 4-year-old girl with a recurrent craniopharyngioma and a missed diagnosis of RT-induced Moyamoya syndrome. Her clinical condition deteriorated a day after uneventful re-exploratory transcranial surgery. She succumbed to bilateral internal carotid artery territory infarcts that were angiographically confirmed to be secondary to MMS. This case underscores the importance of diagnosing RT-induced vasculopathy, a complication that can occur as early as 10 months after completion of RT. Treatment of the condition includes medical management and performing revascularization procedure(s). If these patients require re-exploratory surgery for tumor recurrence, a trans-nasal approach should be used. This avoids the disruption of existing trans-dural collaterals—a phenomenon that could occur with transcranial surgery.