CHORIOCAPILLARIS STRUCTURE IN THE FELLOW EYES OF PATIENTS WITH NEOVASCULAR AGE-RELATED MACULAR DEGENERATION: An OCT Angiography Image Averaging Study

Purpose:Histological choriocapillaris abnormalities have been reported in age-related macular degeneration (AMD). Averaging multiple en face optical coherence tomography angiography improves the quality of imaging of the choriocapillaris. This study used multiple en face swept source optical coherence tomography angiography image averaging to examine the structural changes in the choriocapillaris in the fellow eyes of patients with neovascular AMD. Methods:All patients underwent macular optical coherence tomography angiography imaging. One eye per subject was repeatedly imaged, and nine raster scan sets were obtained. Registered en face images were averaged, and area of flow voids and number of flow voids were measured using ImageJ software. Results:Forty-eight patients with neovascular AMD were recruited for analysis. Twenty-seven patients had polypoidal choroidal vasculopathy, and 22 eyes had soft drusen. Twenty-six eyes of 26 healthy individuals were included as age-matched normal controls. The choriocapillaris had a meshwork appearance in all eyes. The mean flow void area of the choriocapillaris was larger in patients with AMD than normal controls (1.14 0.16 mm(2) vs. 1.01 +/- 0.12 mm(2), P = 0.002). The mean size of each flow void was greater in patients with AMD than normal controls (729 +/- 210 mu m(2) vs. 583 +/- 120 mu m(2), P = 0.003). The mean flow void area of the choriocapillaris was larger in eyes with soft drusen than without soft drusen (1.2 +/- 0.2 mm(2) vs. 1.1 +/- 0.1 mm(2), P = 0.024). Conclusion:Multiple en face image averaging revealed precise choriocapillaris structures in the fellow eyes of patients with neovascular AMD.