Visual outcome after intravitreal triamcinolone acetonide depends on optical coherence tomographic patterns in patients with diffuse diabetic macular edema

Purpose: To evaluate the effectiveness of intravitreal triamcinolone acetonide (IVTA) on the reduction of diffuse diabetic macular edema with different optical coherence tomographic patterns. Methods: One hundred and thirty-five eyes with diffuse diabetic macular edema without any treatment that had received a single dose (4 mg in 0.1 mL) of IVTA were retrospectively examined. Each preoperative macular optical coherence tomographic image was classified according to its appearance as follows: sponge-like diffuse retinal thickening, cystoid macular edema (CME), and serous retinal detachment (SRD). Central macular thickness with optical coherence tomographic images and visual acuity with a logarithm of the minimum angle of resolution chart were assessed at 3 months postoperatively. Results: Of 135 eligible eyes, 49 eyes were identified as having only sponge-like diffuse retinal thickening, 45 eyes with CME, and 26 eyes with SRD. Of those 135 eyes, 15 eyes exhibited the combination of all types of diffuse diabetic macular edema, defined as FULL. After IVTA, central macular thickness was reduced to 31.0 ± 15.9% in the sponge-like diffuse retinal thickening, 40.7 ± 14.2% in the CME, 23.4 ± 15.0% in the SRD, and 25.8 ± 14.8% in the FULL group (P < 0.001; one-factor analysis of variance), while improvement in logarithm of the minimum angle of resolution visual acuity was -0.26 ± 0.21 in the sponge-like diffuse retinal thickening, -0.32 ± 0.20 in the CME, -0.17 ± 0.20 in the SRD, and -0.14 ± 0.22 in the FULL group (P = 0.018; one-factor analysis of variance). Conclusion: The effectiveness of IVTA on diffuse diabetic macular edema was dependent on the optical coherence tomographic pattern, and IVTA was found to be more effective in patients with CME, while IVTA was less effective in those with SRD.