Clinical features

Possible features:

• sudden and profound, painless loss of vision; in branch occlusion, visual defect corresponds to branch affected
• affected pupil is poorly reactive to light, if at all; consensual light reaction is normal
• retina is pale and opaque due to oedema
• retinal arteries are irregular and appear as red threads
• lacking the inner retinal layers, the fovea remains transparent and presents a conspicuous "cherry red spot" due to transmission of the choroidal circulation
• optic atrophy develops after a few weeks, the optic nerve becoming dead white

Occlusion due to vasospastic disease is transient, and vision usually returns within a few hours. Occlusion by emboli may be preceded by episodic flickering as minute emboli interrupt blood flow before disintegrating and passing to the periphery.