Radiation Optic Neuropathy

Radiation optic neuropathy is a devastating late complication of radiotherapy to the anterior visual pathway, first reported in the literature in 1930. In approximately 25% of cases both optic nerves are affected. Effort is usually made to protect the visual pathways with shields, careful radiation dosing protocols, and more precise radiation modalities, and yet RON continues to be reported in the literature. Cases have been seen following external beam radiation, stereotactic radiosurgery, proton beam radiotherapy and whole brain radiation in patients who have been treated with concomitant chemotherapy (Vincristine, Temozolomide and Cisplatin).