Pilocytic astrocytoma, light micrograph. Optic nerve gliomas are爌ilocytic astrocytomas爐hat may燼rise sporadically or燽e seen in the setting of爊eurofibromatosis type 1 (NF1)爑sually in the爌ediatric age group. Most patients present燽etween the ages of 2 and 6 yrs. with爑nilateral loss of vision燼nd燼xial proptosis. About 15% of patients with NF1 will develop optic nerve glioma.燭he tumour consists of a uniform population of astrocytic cells with thin delicate hair-like processes imparting a fibrillar appearance to the background. The nuclei are round to oval with bland chromatin. Optic nerve gliomas are benign tumours that don't threaten the life of the child but impair the vision.