A 65-year-old hypertensive patient develops sudden painless loss of vision in the right eye. FFA shows delayed arteriovenous transit time, retinal hemorrhages in all quadrants in a 'flame and dot' pattern (blood and thunder fundus), disc edema, and dilated tortuous veins. The diagnosis is central retinal vein occlusion (CRVO). Which finding on examination would indicate ischemic CRVO (high risk for neovascular complications) rather than non-ischemic CRVO?
- A Best-corrected visual acuity of 6/18
- B Presence of disc edema
- C More than 10 disc areas of retinal capillary non-perfusion on FFA ✓
- D Bilateral presentation
Correct answer: C. More than 10 disc areas of retinal capillary non-perfusion on FFA
Explanation
Ischemic CRVO (approximately 20% of cases) is defined by more than 10 disc areas (DA) of retinal capillary non-perfusion on FFA, and carries a 45% risk of anterior segment neovascularization (rubeotic glaucoma) within 90 days ('90-day glaucoma'). Additional indicators of ischemia include visual acuity worse than 6/60, relative afferent pupillary defect (RAPD), and ERG changes. Non-ischemic CRVO has visual acuity typically 6/60 or better. Disc edema and bilateral presentation are not specific indicators of ischemic type.
Reference: Khurana Comprehensive Ophthalmology, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.