A patient with bilateral proliferative diabetic retinopathy is planned for panretinal photocoagulation (PRP). Which of the following best explains why 'focal/grid laser' is preferred over PRP for centre-involving DME?
- A Focal laser selectively ablates the RPE at the fovea
- B PRP can worsen macular oedema by increasing VEGF production after ischaemia ✓
- C Grid laser specifically closes leaking hard exudates
- D PRP is contraindicated in all forms of diabetic retinopathy
Correct answer: B. PRP can worsen macular oedema by increasing VEGF production after ischaemia
Explanation
PRP ablates ischaemic retina, reducing VEGF production overall, but the immediate post-treatment inflammatory response and induced macular traction can transiently worsen macular oedema. This is why, when centre-involving DME coexists with PDR requiring PRP, anti-VEGF therapy is typically given first (or concurrently) to stabilise macular oedema before or during PRP. PRP is not contraindicated in DR — it remains the gold standard for high-risk PDR.
Reference: Khurana Comprehensive Ophthalmology, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.