Retina and Vitreous
This domain tests diabetic retinopathy, AMD, retinal detachment, vascular occlusion, vitreous hemorrhage, and ROP. Expect image-free vignettes that require staging and first-line treatment.
Core retina
- Diabetic retinopathy: NPDR progresses to PDR. The ETDRS 4-2-1 rule defines severe NPDR: hemorrhages in 4 quadrants, venous beading in 2, IRMA in 1. Macular edema is treated with anti-VEGF first-line; PRP is for high-risk PDR.
- AMD: dry disease has drusen and geographic atrophy; wet disease has CNV. Anti-VEGF treats wet AMD; AREDS2 supplements help intermediate dry AMD.
- Rhegmatogenous retinal detachment: flashes, floaters, curtain. Laser for small tears; vitrectomy or scleral buckle for detachment.
- CRVO and BRVO: anti-VEGF for macular edema; PRP for neovascularization.
- Vitreous hemorrhage: ultrasound if the view is obscured; rule out tumor and detachment.
- ROP: screen infants under 32 weeks or under 1500 g; stages 1–5; plus disease warrants laser or anti-VEGF.
Worked example
A 68-year-old has sudden painless vision loss with a cherry-red spot and pale retina. Reasoning: this is CRAO, not CRVO. CRVO shows a blood-and-thunder fundus. CRAO is a stroke equivalent; check ESR/CRP and carotid status, and lower IOP.
Traps
Anti-VEGF does not treat dry AMD. PRP is not for macular edema. Do not miss retinal detachment in a hazy vitreous.