Multiple Effects of Intravitreal Aflibercept on Microvascular Regression in Eyes with Diabetic Macular Edema
Abstract Purpose To evaluate the effects of intravitreal aflibercept (IVA) on the microaneurysms (MAs) and sizes of non-perfused areas (NPAs) in eyes with diabetic macular edema (DME). Design Interventional, prospective study. Participants Twenty-five eyes of 25 DME patients (average age, 64.0±8.8 years) were treated with 3 consecutive monthly IVA injections. Methods Fluorescein angiography (FA) and optical coherence tomography were performed prior to the IVA injections(baseline) and at 1 week after the IVA treatment. The number of MAs and the ischemic index (ISI), a measure of the NPAs, were determined. The correlations between central retinal thickness (CRT) and number of MAs and the ISI were also determined. Main Outcome Measures The mean number of MAs and NPA evaluated as the ISI. Results At the baseline, the mean central retinal thickness (CRT) was 485.7±90.6 μm. After treatment, the mean CRT was significantly reduced to 376.9±81.6 μm ( P =0.1 x10 -5 ; repeated ANOVA). The mean number of MAs was significantly decreased from 49.6±33.2 at the baseline to 24.8±18.1 at 3 months after the initial treatment. This was a 50.4±21.2% reduction ( P =0.3 x10 -5 , paired t tests). The mean ISI was also significantly decreased from 55.5±20.4% at the baseline to 28.8±16.8% after the treatment ( P =0.3 x10 -5 , paired t test). This was a reduction of 43.3±28.5%. A significant correlation was found between the CRT and number of MAs at both the baseline (r=0.56, P =0.004) and after the treatment (r=0.53, P =0.006). A significant correlation was found between the CRT and the ISI at the baseline (r=-0.39, P =0.03) but not after the treatment (r=-0.06, P =0.79). Conclusions The reduction in the number of MAs was correlated with the reduction in the CRT.