Choroidal neovascularization imaging using multiple en face optical coherence tomography angiography image averaging

Purpose To determine the effects of averaging five en face optical coherence tomography angiographic (OCTA) images on the quality of the images in eyes with a choroidal neovascularization (CNV). Methods Twenty-seven eyes of 25 patients (18 men, 7 women; average age 71.0 years) with a CNV were examined by OCTA (OCT HS-100, Canon. Japan). A 3 × 3-mm image including the CNV was recorded and automatically segmented between the retinal outer layers. Analyses were performed on a single image (S-image) and the average of five single images of the same area (A-images). The region of the CNV was selected by ImageJ, and the peak signal-to-noise ratio (PSNR), the vascular density (VD), fractal dimension (FD), and the noise component using band pass filter (BPF) processing of the S- and A-images of each case were compared. Results The average PSNR for the A-images was 14.0 which was significantly higher than the 12.2 for the S-images ( P 0.1). The average FD was 1.67 for the S-images and 1.54 for the A-images ( P