The DRCR Protocol S trial compared intravitreal ranibizumab with panretinal photocoagulation as the initial treatment for proliferative diabetic retinopathy. What was the principal conclusion relevant to exam practice?

• A PRP produced significantly better final visual acuity than ranibizumab
• B Combination therapy was required to achieve regression of neovessels in most eyes
• C Ranibizumab increased the rate of tractional retinal detachment compared with PRP
• D Ranibizumab was noninferior to PRP in visual acuity outcomes at five years ✓

Explanation

Protocol S demonstrated that monthly ranibizumab as initial therapy for PDR was noninferior to PRP for mean visual acuity change over five years, with less peripheral field loss and less development of center-involving edema in the injection arm. Its main drawback is the burden of frequent visits, so PRP remains preferred where follow-up is unreliable. Option A reverses the actual direction of the small acuity differences observed.

Reference: AAO Basic and Clinical Science Course, Section 12: Retina and Vitreous, 2023-2024 ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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