Intravitreal triamcinolone as an adjunct to standard laser therapy in coexisting high-risk proliferative diabetic retinopathy and clinically significant macular edema.

PURPOSE: To evaluate the efficacy and safety of combined intravitreal triamcinolone acetonide (IVTA) injection plus panretinal photocoagulation (PRP) and macular photocoagulation (MPC) in comparison with PRP and MPC in eyes with coexisting high-risk proliferative diabetic retinopathy (PDR) and clinically significant macular edema (CSME).

METHODS: Twenty-three patients diagnosed with both high-risk PDR and CSME were enrolled in our prospective, randomized clinical trial study. One eye of each patient was selected to undergo IVTA injection one week before initial PRP and MPC (IVTA eye), and the other eye was treated with PRP and MPC (control eye) based on block randomization. Panretinal photocoagulation was performed in 3 sessions at 1 week intervals. Baseline characteristics included best-corrected visual acuity (BCVA) using Snellen charts, intraocular pressure and patients were observed at 1, 4, and 6 months of treatment. Main outcome measures included change in central macular thickness (CMT) as measured by optical coherence tomography (OCT), logarithm of the minimum angle of resolution BCVA (logMAR), and complications occurring within the follow-up period.

RESULTS: Of 23 enrolled patients, 5 patients did not complete follow-up visits due to dense vitreous hemorrhage, tractional retinal detachment and loss of future follow-up. Mean baseline logMAR BCVA was 0.46 +/- 0.29 and 0.56 +/- 0.27 in IVTA eyes and controls. Final mean logMAR BCVA was 0.39 +/- 0.29 (IVTA eyes) and 0.55 +/- 0.33 (control eyes), which was not significantly different (P = 0.08). Mean baseline CMT was 319.2 +/- 79.1 microm (IVTA eyes) and 345.9 +/- 100.6 microm (control eyes). Significant reduction of CMT in IVTA eyes was observed at 1 month (P = 0.024), which had not remained stable after 6 months showing no significant difference as compared with baseline CMT (P = 0.06). In control eyes, CMT was not significantly reduced at 1 and 6 months of treatment. The standardized change in macular thickening (SCMT) was 29.4 +/- 52.2 (IVTA group) versus 5.66 +/- 31.5 (control group) (P = 0.12) at 1 month. At 6 months, SCMT was 16.8 +/- 55.8 (IVTA group) versus 5.03 +/- 47.4 (control group) (P = 0.51).

CONCLUSION: Combined IVTA plus PRP and MPC in coexisting high-risk PDR and CSME eyes do not have a significant beneficial effect on BCVA improvement and CMT reduction compared with standard treatment.