Abstract
Purpose: :
To evaluate the efficacy and safety of intravitreal triamcinolone and bevacizumab in separate and combined treatment of macular edema due to diabetic retinopathy (DR).
Methods: :
Randomized multicenter clinical study with injection of 0.05ml (1.25 mg) bevacizumab (AVA group); 0.1 ml (4mg) triamcinolone acetonide (TAAC group); and the combination of the two drugs at the same dosage (AVA+TAAC group). Patients were randomized 1:1:1 for monthly injection for 6 months. The following parameters were evaluated monthly: best corrected visual acuity, slit lamp biomicroscopy, intraocular pressure (IOP) and fovea thickness using optical coherence tomography (OCT) as well. Patients were eligible for enrollment if they presented with diabetic macular edema, best corrected visual acuity between 20/400 and 20/40 and central subfield macular thickness ≥275 µm by OCT. Patients were excluded if they had prior proliferative diabetic retinopathy , laser photocoagulation, intraocular injection of corticosteroid or anti-VEGF therapy in the previous 3 months. The primary end points evaluated were visual acuity, central subfield thickness by OCT and IOP. Failure was defined by indication for laser treatment.
Results: :
Sixty-five eyes of 65 patients were injected and 18 eyes completed the study (3 eyes in the AVA group, 6 eyes in the TAAC group and 9 eyes in the AVA+TAAC group). Patients gained 2.3 lines of vision in AVA group, 1.7 in TAAC group and 2.2 in AVA+TAAC group. The central subfield thickness by OCT decreased 17% in the AVA group, 33% in the TAAC group and 26,11% in the AVA+TAAC group after 6 months of follow up. Ten eyes were excluded (increase of IOP in 4 eyes; no lines of vision gained and no decrease in central subfield thickness by OCT in 3 eyes and one patient had myocardium infarct while another patient died from another problem). No systemic side effects were observed in the groups.
Conclusions: :
All groups showed short-term improvement in visual acuity and decreased diabetic macular edema after 3 injections, but at this point of the study there was no difference between the 3 groups. This finding indicates that the different types of treatment tend to similar results and provides evidence against the use of steroids because of their complications. This trial still on-going in the follow-up phase and further results will be reported in near future.
Keywords: diabetic retinopathy • macula/fovea • drug toxicity/drug effects