A 60-year-old diabetic patient undergoes optical coherence tomography angiography (OCTA). The image shows a well-demarcated avascular zone with irregular margins in the superficial capillary plexus. This finding is most consistent with:
- A Foveal avascular zone enlargement due to capillary non-perfusion ✓
- B Normal foveal avascular zone variation
- C Macular neovascularization
- D Epiretinal membrane traction
Correct answer: A. Foveal avascular zone enlargement due to capillary non-perfusion
Explanation
In diabetic retinopathy, OCTA frequently reveals FAZ enlargement with irregular, scalloped margins due to pericyte loss and capillary dropout. A normal FAZ is approximately 0.3 mm² with smooth borders. Enlarged irregular FAZ correlates with macular ischemia and visual prognosis. Macular neovascularization would show abnormal flow signal outside normal capillary layers, not FAZ enlargement.
Reference: Khurana Comprehensive Ophthalmology, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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