Optic Nerve Sheath Meningioma in the First Decade of Life: Case Report and Review of the Literature

BACKGROUND/AIM: Tumors of the optic nerve are mostly either optic nerve gliomas or optic nerve sheath meningiomas (ONSMs). While gliomas occur in children, most meningiomas are slow-growing tumors affecting middle-aged individuals with progressive visual loss, proptosis, disc edema and optociliary veins on fundus examination. ONSMs are extremely rare in children, with only 14 cases reported in children under the age of 10 years. The purpose of this study is to describe an additional case and review clinical, radiologic and histopathological findings that can help differentiate such tumors in children and allow an early and accurate diagnosis. CASE REPORT: An 8-year-old girl had a 2-year history of progressive proptosis and total visual loss on the right side. A computed tomography scan revealed a well-defined intraconal mass with perioptic calcification. Magnetic resonance imaging showed a tumor surrounding the optic nerve and extending intracranially, with enhancement following gadolinium injection. The patient was submitted to fronto-orbital craniotomy for complete tumor excision. Histological studies identified the neoplasm as ONSM. CONCLUSIONS: Though unusual, ONSMs may occur in children and, in these cases, present a much more aggressive behavior than in adults. ONSM should therefore be differentiated from optic glioma in children because of its aggressive behavior and need for different treatment modalities.