Endoscopic Endonasal Optic Nerve Decompression in Optic Nerve Sheath Meningiomas

Objective: To describe our technique and report on the visual outcome in a cohort of patients who underwent an endoscopic endonasal optic nerve decompression for optic nerve sheath meningioma (ONSM).

Design: Retrospective review of endoscopic endonasal approaches (EEAs) to the orbit performed at the University of Pittsburgh Medical Center between 2006 and 2011.

Patients, Materials, and Methods: The patients' clinical charts, operation notes, and imaging were reviewed. Their visual outcomes were assessed independently by a neuroophthalmologist to include visual acuity, color discrimination, pupillary function, extraocular movements, exophthalmometry, optic disc appearance, and visual fields.

Results: Eight patients with nine meningiomas were identified, with one patient having bilateral ONSMs. Eight meningiomas presented with progressive visual failure, two with proptosis, and three with orbital pain. All meningiomas were treated with an endoscopic medial orbit bony decompression; two also had a biopsy, and one a subtotal resection. Two also underwent a pterional craniotomy for circumferential decompression of the optic nerve. Two meningiomas underwent adjuvant stereotactic radiosurgery. The median follow-up was 15.2 months (range, 1 to 56 months).

Seven of the eight meningiomas presenting with visual loss improved postoperatively, while in 1 meningioma the EEA halted the progression of the visual failure during the follow-up period. None of the nine eyes' vision was worsened by surgery. All patients with proptosis and pain improved postoperatively.

Conclusions: The EEA provides a safe and anatomically favorable option for decompression as part of the treatment strategy for patients with unresectable optic nerve sheath meningiomas with progressive visual failure.