Effect of microaneurysms on the anti-VEGF treatment for diabetic macular edema: A retrospective cross-sectional study

Although anti-vascular endothelial growth factor (VEGF) treatment is effective for treating diabetic macular edema (DME), the effect of the microaneurysm (MA) status on the therapeutic efficacy of an anti-VEGF treatment remains unclear. Our current study investigated the effects of the number and the presence or absence of leaking MAs on DME and the efficacy of anti-VEGF therapy. A total of 51 eyes of 47 DME patients were administered anti-VEGF treatment. Fluorescence angiography results were used to determine the number of MAs and the presence or absence of leakage, with these findings matched to the optical coherence tomography maps. The correlation between the number of MAs and the retinal thicknesses and the influence of the leaking MAs was examined in order to definitively determine the effect of the anti-VEGF treatment. There was a correlation between the number of MAs and the retinal thickness of the sector in both the 6 mm (correlation coefficients: 0.42) and 3 mm (0.34) sectors (P < .001). There was also a correlation between the number of MAs and the retinal thickness in both the 6 mm (0.31) and 3 mm (0.24) sectors after undergoing the treatment (P < .01). There was a significant difference between the mean thickness of the leaking versus the non-leaking MAs in the 6 mm (388 ± 87 μm) and 3 mm (477 ± 108 μm) sectors before treatment (P < .01). There was also a significant difference for the retinal thickness between the sectors with and without leaking MAs after the treatment (P < .01). The degree of retinal edema before treatment is associated with the number of MAs and the presence of leaking MAs. Anti-VEGF treatment is less effective for focal macular edema with large numbers of MAs, which includes leaking MAs.