Central Retinal Artery Occlusion
- Infarction of retina
- Caused by thrombotic or embolic occlusion of retinal arteries
- Sources of thrombosis are systemic hypertension, dyslipidemia, hypercoagulable states
- Sources of embolism are atheromas of cervical carotid bifurcation or abnormalities of cardiac valves, wall, or rhythm
- Sudden painless loss of vision usually confined to one eye
- Afferent pupil defect in affected eye
- Milky appearance of retina because ischemic swelling causes loss of its transparency
- Cherry-red spot in fovea (spared because it is nourished by choroidal rather than retinal arteries)
- Nothing, but...
- Distinctive milky white retina with cherry red spot may not develop for first 24 hours
- Consider this diagnosis in patient with sudden monocular persistent loss of vision especially if afferent pupil defect present
- Refer emergently to ophthalmologist or emergency room
- No effective treatment (including thrombolysis, anticoagulation), but...
- Patient needs evaluation for stroke-prone state
- Some vision may return spontaneously