Teaching NeuroImages: T2 hyperintensities in neurofibromatosis type 1.

Abstract

A 4-year-old boy with neurofibromatosis type 1 (NF1), an asymptomatic optic glioma, and a right basal ganglia T2-hyperintense lesion (figure, A and B) developed a left hemiparesis with hyperreflexia over the course of a year. Neuroimaging revealed a cyst-like mass in the region of his previously identified T2 hyperintensity (figure, C and D). While it is often difficult to distinguish T2 hyperintensities from low-grade glioma without tissue diagnosis,¹ even with advanced imaging methods,² T2 hyperintensities typically disappear with age and do not become cystic with associated mass effect. Coupled with the development of new neurologic signs, these MRI features are worrisome for neoplasm in a patient with NF1.