Radiation Optic Neuropathy

Radiation-induced retinopathy and radiation-induced optic neuropathy (RION) are rare and disabling late-onset complications of ocular irradiation. Radiation-induced retinopathy is characterized by progressive, occlusive vasculopathy, leading to subsequent retinal inflammation, edema, ischemia, and neovascular proliferation. These changes ultimately lead to retinal hemorrhage, maculopathy, and gradual decline in visual acuity. In contrast, optic neuropathy involves the optic nerve or chiasm and may present with sudden onset of visual changes. Both can lead to profound and irreversible vision loss and substantial disability and are thus critically important to consider in the treatment of any intracranial or base of skull disease.