Temporal variation of optical coherence tomography biomarkers as predictors of anti-VEGF treatment outcomes in diabetic macular edema

Purpose To report a longitudinal analysis of specific optical coherence tomography (OCT) features in eyes with diabetic macular edema (DME) treated with anti-VEGF. Methods A total of 133 eyes of 103 consecutive patients with center-involving DME were included in the study. The eyes were treated between August 2008 and April 2019 with three monthly intravitreal anti-VEGF injections, either with or without prompt or deferred laser, followed by pro re nata (PRN) re-treatment. The following OCT biomarkers were evaluated: subfoveal neuroretinal detachment (SND) (defined as present (SND+) or absent (SND-)), hyperreflective retinal foci (HRF) number (defined as: absent/few(HRF-) or moderate/many (HRF+)), external limiting membrane (ELM) integrity, central macular thickness (CMT), and central retinal thickness (CRT). Changes in SND status and in the number of HRF were evaluated at each DME recurrence throughout the follow-up(FU) period. Mutual correlation among OCT biomarkers and their relationship with visual and anatomic outcomes were assessed both at baseline and over the FU period. Results The mean FU was 71.2 months (SD 28.4; min. 12–max. 111). At baseline, the prevalence of SRD+ was 27.8% and a high number of HRF were detected in 41.4% of the eyes. A significant reduction in the number of HRF, CMT, CRT, and in the prevalence of SND was recorded in the post-loading phase ( p -value