Abstract
Twenty-seven patients with a meningioma arising from within the optic nerve sheath have been seen during the past 12 years. Twenty-one were women, the majority aged 39--64 years. The men were younger, all except 1 being between 20 and 41 years when first seen. There were no patients younger than 20 years. Twenty-two patients had noticed a deterioration in the vision as their initial symptom. The optic nerve head was abnormal in all patients; 14 were swollen and 13 atrophic and flat. Neurofibromatosis was not associated with this condition. Treatment was essentially surgical.