Reduction in the frequency of intravitreal bevacizumab administrations achieved by posterior subtenon injection of triamcinolone acetonide in patients with diffuse diabetic macular edema

Abstract

Purpose: To evaluate the effectiveness of posterior subtenon injections of triamcinolone acetonide (STTA) during treatment with intravitreal injections of bevacizumab (IVB) in eyes with diffuse diabetic macular edema (DDME).

Methods: Forty eyes of 20 patients with bilateral DDME with foveal thickness (FT) greater than 400 μm were studied. Initially, both eyes of each patient received 1.25 mg/0.05 ml of IVB. One eye then received 20 mg/0.5 ml of STTA at the onset and at 16, 32, and 48 weeks. For the control, the other eye was not treated with STTA. Patients were treated with additional IVB when DDME recurred during the study to maintain the FT at <350 μm. The FT, logMAR visual acuity (VA), and intraocular pressure (IOP) were monitored monthly for 56 weeks. The total number of IVB injections during the 1-year follow-up was also calculated.

Results: STTA-treated eyes had significantly more regression of FT and improvement of VA at several time points during the study than did the controls. The mean (SD) required number of IVB injections in the STTA-treated eyes during the study was 5.00 ± 1.75, which was significantly less than the 7.95 ± 1.57 in the control eyes.

Conclusions: Adjunctive STTA therapy to IVB for the treatment of DDME not only improved the morphological and functional regressions but also reduced the frequency of IVB treatments.

Keywords: Bevacizumab; Combination therapy; Diabetic macular edema; Subtenon injection; Triamcinolone acetonide.