Clinical Course of Optic Nerve Sheath Meningioma

ABSTRACT

PURPOSE: To evaluate the clinical course of optic nerve sheath meningioma (ONSM) in Korean patients. METHODS: A retrospective study of 11 eyes of 11 patients with a diagnosis of ONSM between 2002 and 2015 at Severance Hospital. RESULTS: The mean age at symptom onset was 47.6 years. Ten females and 1 male participated in the study and all tumors were unilateral. Patients typically presented with visual loss and proptosis. Three patients complained of limited extraocular movements and seven patients exhibited visual field defects. Three patients who had a greater growth rate with intracranial involvement and two patients who had decreased vision received treatments. Five patients maintained good vision and visual field during the follow-up period. However, one patient who underwent surgical treatment presented significant visual loss and deterioration of visual field defect. One out of two patients who received three-dimensional conformal radiotherapy (3D-CRT) experienced improvement in visual field, and the other showed no change in visual field defect but remained stable with decreased tumor size. One out of two patients who underwent gamma-knife surgery showed aggravated visual field defect and the other presented with visual loss. CONCLUSIONS: ONSM is typically a slow-growing tumor. Deterioration of visual loss and visual field defect can occur after treatment of ONSM. Therefore, management should be considered carefully and should be limited to cases in which progression of the disease is advanced or tumor growth is fast. 3D-CRT can be considered in patients in need of treatment.