RADIATION-INDUCED OPTIC NEUROPATHY

Abstract

Radiation-induced optic neuropathy (RION) is a disabling late complication of radiotherapy leading to irreversible severe visual impairment or even total visual loss which may affect one or both eyes. Although not fully understood yet, RION is proposed to be a consequence of endothelial and neural cell injury with resultant necrosis. Risk factors include the patient and disease related factors, radiotherapy technique, per fraction and total radiotherapy doses. Currently there is no well-established treatment modality for RION, and usually the various drug therapies fail to reverse the visual loss. Therefore, currently the simplest but most effective treatment of RION is prevention of its occurrence by utilizing more sophisticated radiotherapy techniques and strict adherence to the published dose constraints for optic apparatus. Present review mainly aims to provide an overview of the currently accessible evidence on pathogenesis, risk factors, and treatment of RION.