Silas Wang, Presenter: Nothing to Disclose

James Byunghoon Yu MD, Abstract Co-Author: Nothing to Disclose

Robert L. Lesser MD, Abstract Co-Author: Nothing to Disclose

Jonathan P.S. Knisely MD, Abstract Co-Author: Nothing to Disclose

Primary optic nerve sheath meningiomas (ONSM) are generally benign but cause progressive visual loss. Surgical excision has not generally been successful in preserving visual function, but recent reports have shown fractionated radiotherapy (RT) to be effective in stabilizing or improving visual function and radiographic appearance. We reviewed outcomes of conformal RT in patients with ONSM to determine the treatment efficacy and safety.

We retrospectively reviewed 12 consecutive cases of ONSM diagnosed clinically and radiographically that were treated with primary conformal fractionated external-beam RT.

The patients received 45.00 to 52.19 Gy in 25 to 29 fractions of 1.8 Gy each. Ten patients received three-dimensional conformal RT with thermoplastic mask immobilization, 1 received stereotactic fractionated RT, and 1 received intensity-modulated RT. The patients were followed for 7 to 124 months (mean 47.4, median 34.0). Visual acuity and visual field were stable or improved in 100% of patients. Radiographic control of the tumor was demonstrated in 100% of patients, with a decrease in size seen in 3 (25.0%). Acute toxicity was transient and generally mild, and included focal alopecia, fatigue, mucositis, and nausea. Late complications included 1 case of dry eye syndrome and 1 case of post-radiation hormonal changes.

Primary fractionated RT was effective and safe in our series with a median follow-up of nearly 3 years. These outcomes compare favorably to those in the published literature.

Wang, S, Yu, J, Lesser, R, Knisely, J, Response to Fractionated Radiotherapy of Optic Nerve Sheath Meningiomas.  Radiological Society of North America 2007 Scientific Assembly and Annual Meeting, November 25 - November 30, 2007 ,Chicago IL. http://archive.rsna.org/2007/6001081.html