A 60 yo F with sudden onset loss of vision in right eye, painless. Proceeded by a few episodes of amaurosis fugax.
Physical exam: pupils appear normal on initial inspection, however afferent pupil defect noted.
Fundoscopic exam: cherry red spot, pale retina, +/-boxcar segmentation (not shown in this picture).
DDx for loss/reduction of vision:
Glaucoma, optic neuritis, central retinal artery or vein occlusion
Given the history and physical, the most likely diagnosis is central retinal artery occlusion (CRAO).
Retina can sustain irreversible damage within 90 minutes of complete occlusion, so act fast:
- Consult ophthalmology
- Digital massage to convert the CRAO to BRAO (central to branch): first steady pressure on the globe for 15s, followed by sudden release of pressure; repeat several times
- Administer one drop of Timoptic 0.5% (to suppress aqueous humor production and therefore reducing OIP)
- Acetazolamide 500mg IV or PO once (to suppress aqueous humor production)
- Consider having patient breathe into a paper bag for 5-10 minutes if no respiratory contraindications (to increase PaCO2 as CO2 dilates retinal arterioles)