The DRCR Protocol S evaluated intravitreal ranibizumab against panretinal photocoagulation for proliferative diabetic retinopathy. Its principal conclusion was:

• A PRP produced significantly better visual acuity outcomes than ranibizumab at 5 years
• B Combination therapy was mandatory for all patients with PDR
• C Neither treatment reduced the rate of severe visual loss compared with observation
• D Ranibizumab was non-inferior to PRP for visual acuity outcomes, with less peripheral visual field loss ✓

Explanation

Protocol S demonstrated that ranibizumab monotherapy was non-inferior to PRP for mean change in visual acuity over 2 years (and through 5 years), with less contraction of visual field and lower rates of vitreous hemorrhage and macular edema development. The trade-off is the need for frequent injections and close follow-up. PRP remains preferred where follow-up is unreliable, which is the key practical caveat.

Reference: Ryan's Retina, 6th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.