OCTA changes following loading phase with intravitreal aflibercept for DME.

ABSTRACT

OBJECTIVE: To quantify changes in optical coherence tomography angiography (OCTA) parameters following intravitreal anti-vascular endothelial growth factor treatment for diabetic macular edema (DME), and to assess associations between pretreatment OCTA parameters and visual outcomes. DESIGN: Prospective cohort study. METHODS: Twenty-nine patients with DME received 5 monthly intravitreal injections of aflibercept. OCTA data obtained at baseline and at 6 months were compared using the Wilcoxon signed-rank test. OCTA parameters were foveal avascular zone (FAZ) area, FAZ perimeter, FAZ circularity, vessel density in the superficial vascular plexus (segmented into central, inner, outer, and full Early Treatment of Diabetic Retinopathy Study [ETDRS] map regions. Subanalysis divided patients into treatment responders (reduction of central subfield thickness >50 µm over treatment) and nonresponders. Associations between pretreatment OCTA parameters and visual acuity outcomes were analyzed using multivariable linear and logistic regression. RESULTS: A total of 29 patients were included 25 patients (86.2%) had nonproliferative diabetic retinopathy, and 4 patients (13.8%) had proliferative diabetic retinopathy. Vessel density was reduced in the central (p = 0.004) and inner (p = 0.013) ETDRS map regions. This effect was significant only among treatment responders (central p = 0.002; inner p = 0.017). Pretreatment OCT and OCTA parameters were not associated with final visual acuity outcomes. CONCLUSION: Following intravitreal aflibercept treatment for DME, there was a significant decrease in vessel density of the superficial vascular plexus at the central and inner ETDRS map regions. This was seen only among treatment responders. Observations here are likely to represent the limits of OCTA technology itself, where pretreatment vessel density may have been artifactually overestimated by suspended scattering particles in motion. Pretreatment OCTA parameters did not serve as biomarkers for visual outcome following anti-vascular endothelial growth factor therapy.