A 55-year-old hypertensive patient develops sudden painless vision loss in the right eye. Fundoscopy shows disc edema, flame-shaped hemorrhages in all four quadrants with a 'blood and thunder' fundus, dilated tortuous retinal veins, and cotton-wool spots. The most appropriate investigation to identify the underlying etiology is:

• A Carotid Doppler to identify significant stenosis
• B Blood pressure measurement and fasting blood glucose to identify cardiovascular risk factors
• C Fluorescein angiography to identify ischemic from non-ischemic CRVO ✓
• D Optical coherence tomography to quantify macular edema thickness

Explanation

The described presentation is central retinal vein occlusion (CRVO). The critical clinical distinction is between non-ischemic CRVO (better prognosis, responds to anti-VEGF) and ischemic CRVO (>10 disc areas of non-perfusion, 34% risk of neovascular glaucoma within 3 months). FFA is the gold standard to quantify areas of retinal non-perfusion and guide prophylactic panretinal photocoagulation. While systemic workup (BP, glucose, lipids, CBC) is also required, FFA is the ophthalmic investigation that directly determines treatment and surveillance protocol.

Reference: Khurana Comprehensive Ophthalmology, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.