Abstract
Purpose :
In the presence of macular edema (ME), visibility of ellipsoid zone (EZ) diminishes in OCT images. This study was performed to determine whether ME affects EZ parameters detected by a newly described algorithm.
Methods :
In this IRB-approved retrospective study, patients with treatment naïve retinal vein occlusions and ME were identified. Baseline demographics and spectral domain OCT data (Zeiss, Cirrus) was collected. Macular cube scans were exported into a novel retinal layer analysis software and EZ parameters were evaluated with an automated platform. Manual confirmation of the segmentation lines was performed by an expert reader for accuracy. The en face characteristics that were extracted included global measures [percent of macular surface area with EZ-retinal pigment epithelium (RPE) attenuation (EZ-RPE thickness < 20 µm), percent of macular surface area with EZ-RPE total attenuation (EZ-RPE thickness = 0 µm), EZ-RPE volume], juxta-foveal (JXF) linear measures (JXF nasal, temporal and average EZ-RPE thicknesses), and foveal linear measures (central foveal EZ-RPE area and thickness, and CST EZ-RPE). These parameters were correlated with demographics, baseline visual acuity, OCT parameters [cube volume (CV), cube average thickness (CAT), central subfield thickness], and CME grade.
Results :
189 eyes were included. Age and sex did not affect the EZ-RPE parameters. Vision was inversely associated with global atrophy (p<0.001) and attenuation (p<0.001) and directly associated with all other measures (p<0.001). Lens status affected only the JXF parameters (p<0.05). RVO type did not have any effect on global but had significant effect on macular measures (p<0.003 for all). Subretinal fluid affected all measures (p<0.05). CME grade and CST were positively associated with global EZ-RPE attenuation (p<0.001) and atrophy (p<0.001), and inversely associated with EZ-RPE volume (p<0.01) and macular EZ-RPE measures (p<0.001). CAT and CV were positively associated with global EZ-RPE attenuation (p<0.05) and were inversely associated with macular EZ-RPE measures (p<0.05).
Conclusions :
EZ-RPE parameters are affected by the presence and degree of macular edema, but have a predictable association with vision. Increased atrophy and attenuation are associated with poorer visual acuity; and better EZ-RPE parameters are associated with greater visual acuity.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.