Prolonged vision return after radiosurgery for an optic nerve-sheath meningioma

To report a case of prolonged vision return after stereotactic radiosurgery for an optic nerve-sheath meningioma.

Case report.

Ophthalmologic examination followed by stereotactic radiosurgery for an optic nerve-sheath meningioma.

Ophthalmologic examination and MRI findings.

We report the case of 59-year-old female with visual deterioration and progressive proptosis five years after subtotal resection of a left optic nerve-sheath meningioma. Because of progression to blindness (no light perception), the patient underwent Gamma Knife® stereotactic radiosurgery to the intraorbital meningioma in order to achieve tumor-growth control. Remarkably, within one year, her vision in the ipsilateral eye improved to 20/25, and her MRI scan showed significant tumor regression. Excellent vision persisted for eight years. After that, the left eye vision again decreased to hand movement only. At ten years after radiosurgery her ophthalmological exam confirmed severe optic neuropathy.

Radiosurgery provided a paradoxical benefit in this patient who had complete blindness but had restoration of vision for more than eight years. Delayed eventual visual loss likely resulted from optic nerve long-term adverse radiation effect despite persistent long-term tumor growth control.