Fluorescein fundus angiography (FFA) in a patient with branch retinal artery occlusion shows a hypofluorescent zone in the early arteriovenous phase and hyperfluorescence in the late phase at the same location. The best explanation is:

• A Capillary non-perfusion leading to ischaemic hypofluorescence, then window defect from RPE atrophy ✓
• B Leakage from new vessels in early phase followed by staining
• C Blocked fluorescence from haemorrhage in early phase, staining of fibrous tissue in late phase
• D Choroidal hypoperfusion with choroidal flush in late phase

Explanation

In BRAO the blocked (hypofluorescent) area in early phases reflects ischaemia-related retinal whitening and capillary non-perfusion. Over time the ischaemic retina atrophies, resulting in RPE window defects that produce late hyperfluorescence from underlying choroidal fluorescence. New vessels leak from the start and haemorrhage gives consistent blockage, not conversion to hyperfluorescence.

Reference: Khurana Comprehensive Ophthalmology, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.