Abstract

Optic nerve sheath meningioma arises from the arachnoid cap cell of optic nerve sheath and comprises most of primary orbital meningioma. We experienced a rare case of optic nerve sheath meningioma originating in the left orbit. A 44-year-old woman had suffered from visual disturbance in the left eye for 3 years and had only light perceptibility for the recent 6 months. The right eye was normal. Brain CT scan and MRI revealed a 2x0.8 cm sized fusiform solid mass in the left retrobulbar area. Under the impression of optic nerve tumor. excision of the mass including a small segment of the optic nerve was performed. The tumor was a yellowish firm, relatively well demarcated mass that encircled the optic nerve without infiltrating it. Microscopically it was a typical meningioma, meningothelial type. The recovery of visual acuity was impossible due to resection of optic nerve but there was no evidence of recurrence for u months.

• Keywords: Optic nerve sheath;Meningioma