MRI of optic pathway glioma in a patient with NF1

4-year-old with NF1 and optic pathway glioma. Transverse axial T2-weighted MR images (A1-C1) show a thick and tortuous left optic nerve glioma (thick arrows) and associated hyperintense mass (arrows) in the right optic tract. Hyperintensities in the cerebral peduncles (arrowheads) are consistent with cystic myelinopathy of NF1. Coronal postcontrast, T1-weighted images (A2-C2) show the intensely-enhancing left optic nerve glioma (A2) and the heterogeneously-enhancing component in the right optic tract (B2, C2). Also note nonenhancing tumor (B2, dashed arrow in inset) in right side of the optic chiasm. The level of each coronal image is indicated by the horizontal line on the axial image immediately above.