Moyamoya pattern of vascular occlusion after radiotherapy for glioma of the optic chiasm.
We studied three children who suffered massive strokes 2 to 5 years after intracranial irradiation of optic chiasm gliomas. Arteriography showed moyamoya changes in all three. CTs showed dramatic reduction in tumor size in two patients, but we believe radiotherapy should only be used sparingly to treat optic chiasm gliomas in young children, because its efficacy is unproven, and side effects may be catastrophic.