The prognostic value of total macular external limiting membrane and ellipsoid zone damage for clinical outcome in treatment-resistant neovascular age-related macular degeneration.

To examine the prognostic value of the extent of damage to the ellipsoid zone (EZ) and external limiting membrane (ELM) in response to the treatment of age-related macular degeneration (AMD) eyes switched from ranibizumab to aflibercept. This is a retrospective study of patients with neovascular AMD resistant to ranibizumab defined as having persistent intra- or subretinal fluid on OCT scans despite at least 6-month treatment and switched to aflibercept. Clinical data was collected and quantitative measurements of the area of EZ and ELM damage were obtained, on en-face optical coherence tomography images, at the time of switch to aflibercept (baseline) and up to 6 months of follow-up. The study included 71 eyes (52.1% right eye) of 71 patients. At baseline, there was a correlation between the size of the EZ and ELM damaged area and BCVA (R = -0.39, p = 0.001 and R = -0.47, p < 0.001, respectively). The EZ and ELM damaged areas maintained correlation with BCVA at 6 months (R = -0.28, p = 0.01 and R = -0.39, p = 0.001, respectively). Central retinal thickness did not correlate with BCVA at the time of switch (p = 0.38) or at 6 months (p = 0.36). The extent of damage to the EZ and ELM correlates with BCVA following a switch in treatment.