Optical coherence tomography of radiation optic neuropathy

To quantitatively study morphologic optic disc and retinal changes in patients with radiation optic neuropathy (RON) using optical coherence tomography (OCT).

This study is a retrospective clinical case series of ten patients with acute RON. Each had been treated with palladium-103 ophthalmic plaque therapy for choroidal melanoma. OCT images were taken at the time of the initial RON diagnosis to measure cup depth, cup width, edema, vasculature diameter, and retinal thickness.

All patients with acute RON showed optic disc edema, increased optic disc thickness, and decreased optic cup depth. The average papillary retinal thickness was 341.6 μm and the average optic cup depth was 168 μm. Retinal arteries showed a mean decrease in diameter of 32.5%. All patients with RON in the study showed a decrease in cumulative peripapillary retinal thickness.

This study shows that RON manifests characteristic retinal and optic disc changes that can be evaluated quantitatively by OCT.