Fig 1.
Example of image processing for the quantification of choriocapillaris flow deficits.
(A) The en face choriocapillaris blood flow image without the removal of artifacts. (B) The en face retinal blood flow image. (C) The large retinal vessel map generated from image B. (D) The en face choriocapillaris structural image. (E) The shadowing artifacts on choriocapillaris image with black pixels corresponding to artifacts caused by retinal lesions. (F) The choriocapillaris flow deficits (green color) overlaid onto the en face choriocapillaris blood flow image (gray) after subtraction of artifacts. (G) The choriocapillaris flow deficit binary map for quantification. All images are from the left eye of a 45-year-old diabetic patient with proliferative diabetic retinopathy. All images are 6×6-mm fields.
Table 1.
Demographic and clinical characteristics of the study population.
Fig 2.
Comparisons of CC FD% (left) and mean CC FD size (right) between study groups.
Kruskal-Wallis test with Bonferroni correction was performed in pairwise comparisons of the FD% and the mean FD size, respectively. Brackets indicate statistically significant differences between corresponding study groups. CC, choriocapillaris; FD, flow deficit; FD%, percentage of CC FDs; NPDR, nonproliferative diabetic retinopathy; PDR, proliferative diabetic retinopathy.
Fig 3.
Representative illustration of the SS-OCTA images from a control eye and eyes with different stages of diabetic retinopathy.
First column (A, E, and I): The en face retinal blood flow images. Second column (B, F, and J): The en face choriocapillaris blood flow images without removal of the artifacts. Third column (C, G, and K): The corresponding choriocapillaris flow deficits (green color) overlaid onto the en face choriocapillaris blood flow images (gray) after removal of the artifacts. Fourth column (D, H, and L): The choriocapillaris flow deficit binary maps for quantification. (A–D) Images are from the right eye of a 62-year-old healthy subject. (E–H) Images are from the right eye of a 62-year-old patient with nonproliferative diabetic retinopathy. (I–L) Images are from the right eye of a 60-year-old patient with proliferative diabetic retinopathy. All images are 6×6-mm fields).