PURPOSE: To evaluate laser combined with intravitreal triamcinolone acetonide (IVTA) for the management of patients with proliferative diabetic retinopathy (PDR) and clinically significant macular edema (CSME). DESIGN: Randomized clinical trial. METHODS: settings: Single center. study population: Twenty-two patients with bilateral treatment-naïve moderate PDR and CSME. intervention: Laser (panretinal and macular) photocoagulation was performed in each eye, followed by IVTA in one randomly assigned eye. Best-corrected visual acuity (BCVA), fundus photography, and optical coherence tomography were performed at baseline and at months 1, 3, 6, 9, and 12. main outcome measures: Changes in BCVA, central macular thickness (CMT), and total macular volume (TMV). RESULTS: The mean logarithm of the minimal angle of resolution (logMAR) BCVA improved significantly, and mean CMT and TMV were significantly reduced in the IVTA group compared with the laser-only group (controls) at all study follow-up visits (P < .001). The mean logMAR BCVA (Snellen equivalent) was 0.44 (20/50(-2)) for the IVTA group and 0.38 (20/50(+1)) for the controls at baseline, and 0.12 (20/25(-1)) for the IVTA group and 0.32 (20/40(-1)) for the controls at 12 months (P < .001). The mean CMT and TMV were, respectively, 360 microm and 8.59 mm(3) for the IVTA group and 331 microm and 8.44 mm(3) for the controls at baseline, and 236 microm and 7.32 mm(3) for the IVTA group and 266 microm and 7.78 mm(3) for the controls at 12 months (P < .001). CONCLUSIONS: The combination of laser photocoagulation with IVTA was associated with improved BCVA and decreased CMT and TMV when compared with laser photocoagulation alone for the treatment of moderate PDR with CSME.