['To determine whether scatter and grid laser photocoagulation (laser) adds benefit to ranibizumab injections in patients with macular edema from retinal vein occlusion (RVO) and to compare 0.5-mg with 2.0-mg ranibizumab.', 'Randomized, double-masked, controlled clinical trial.', 'Thirty-nine patients with central RVO (CRVO) and 42 with branch RVO (BRVO).', 'Subjects were randomized to 0.5 mg or 2.0 mg ranibizumab every 4 weeks for 24 weeks and re-randomized to pro re nata ranibizumab plus laser or ranibizumab alone.', 'Mean change from baseline best-corrected visual acuity (BCVA) at week 24 for BCVA at weeks 48, 96, and 144 for second randomization.', 'Mean improvement from baseline BCVA at week 24 was 15.5 and 15.8 letters in the 0.5-mg and 2.0-mg CRVO groups, and 12.1 and 14.6 letters in the 0.5-mg and 2.0-mg BRVO groups. For CRVO, but not BRVO, there was significantly greater reduction from baseline mean central subfield thickness (CST) in the 2.0-mg versus 0.5-mg group (396.1 vs. 253.5 μm; P = 0.03). For the second randomization in CRVO patients, there was no significant difference from week 24 BCVA in the ranibizumab plus laser versus the ranibizumab only groups at week 48 (-3.3 vs. 0.0 letters), week 96 (+0.69 vs. -1.6 letters), or week 144 (+0.4 vs. -6.7 letters), and a significant increase from week 24 mean CST at week 48 (+94.7 vs. +15.2 μm; P = 0.05) but not weeks 96 or 144. For BRVO, there was a significant reduction from week 24 mean BCVA in ranibizumab plus laser versus ranibizumab at week 48 (-7.5 vs. +2.8; P < 0.01) and week 96 (-2.0 vs. +4.8; P < 0.03), but not week 144, and there were no differences in mean CST change from week 24 at weeks 48, 96, or 144. Laser failed to increase edema resolution or to reduce the ranibizumab injections between weeks 24 and 144.'] Does scatter Photocoagulation Reduce Macular Edema or Treatment Burden in Patients with Retinal Vein Occlusion : The RELATE Trial?