In the Early Treatment Diabetic Retinopathy Study (ETDRS), focal laser photocoagulation was shown to reduce the risk of moderate vision loss in clinically significant macular edema by approximately what percentage at three years?
- A 90 percent
- B 75 percent
- C 50 percent ✓
- D 25 percent
Correct answer: C. 50 percent
Explanation
The ETDRS demonstrated that focal/grid laser photocoagulation reduced the risk of moderate visual loss (doubling of the visual angle) by approximately 50 percent at three years in patients with clinically significant macular edema. This landmark finding established laser as the standard of care before the anti-VEGF era. The exact figure is 50 percent, making option C correct.
Reference: Early Treatment Diabetic Retinopathy Study Research Group, Archives of Ophthalmology, 1985;103 ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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