Central retinal artery occlusion
With thanks to Yusuf.
emboli – thrombotic, fat, amniotic fluid, air – AGE
compression in the orbit – retroorbital haematoma; thyroid exophtalmos
Symptoms: severe loss of vision that develops over seconds; painless
Examination: decreased VA; prominent afferent pupillary defect; fundoscopic exam: macular cherry red spot (fovea – sparred) with a pale retina and less pronounced arteries
Treatment: depends on the cause
Thromboembolic causes: aim to dislodge the clot from the main artery to one of its branches:
– digital massage (digital pressure through closed eyelids for 10 – 15 sec then sudden release)
– vasodilation (by increasing pCO2 – rebreathing into a paper bag)
– lowering intraocular pressure – topical Bblockers; iv acetazolamide; anterior chamber paracentesis
Vasculitis: corticosteroids (1 – 2 weeks to loss of vision in the other eye if not treated)
Sickle-cell crisis: iv fluids, reverse precipitant cause
Decompression sickness: hyperbaric therapy
They all need urgent Ophtalmology referral.