Intravitreal triamcinolone for diabetic macular edema: comparison of 1, 2, and 4 mg.

Purpose: To compare the efficacy and safety of different doses of intravitreal triamcinolone (IVTA) in treating eyes with refractory diffuse diabetic macular edema (DME) with cystic changes.
Methods: Forty-five eyes of 45 patients with diffuse DME were randomized to receive 1, 2, or 4 mg IVTA. Patients were observed for 6 months and changes in best-corrected visual acuity (VA) in Early Treatment Diabetic Retinopathy Study (ETDRS) scores, retinal thickness analyzer (RTA) central macular thickness (CMT), intraocular pressure, and cataract progression were compared among the three groups.
Results: Forty-two patients completed 6 months of follow-up and were included in the analysis. Following IVTA injection, the ETDRS score improved similarly, eight to nine letters, in all three groups at 4 weeks. The standardized CMT improved in all three groups at 4 weeks. This improvement was maintained through 12 and 24 weeks in the 1 and 2 mg groups, but not in the 4 mg group, which was significantly worse than the 1 and 2 mg groups at 12 and 24 weeks (P = 0.01, 0.03, 0.01, and 0.05).
Conclusions: Regarding eyes with refractory diffuse DME with cystic changes, 4 mg IVTA does not appear to be more effective than 1 or 2 mg IVTA.