Table 2. Descriptive Statistics for Density Metrics and Foveal Avascular Zone (FAZ) Area in the Superficial Retinal Layer (SRL) and the Deeper Retinal Layer (DRL) for Both Groups.
| Statistic | Perfusion Densitya | Vessel Density, mm-1 | FAZ Area, mm2 | FAZ Perimeter, mm | FAZ Circularity Index | ||
|---|---|---|---|---|---|---|---|
| SRL | DRLb | SRL | DRLb | ||||
| Healthy eye group | |||||||
| Mean (SD) [range] | 0.419 (0.007) [0.401-0.436] |
0.337 (0.034) [0.234-0.380] |
22.5 (0.7) [21.3-23.9] |
17.7 (1.9) [11.8-20.5] |
0.25 (0.10) [0.04-0.49] |
2.05 (0.53) [0.15-2.89] |
0.82 (0.06) [0.67-0.94] |
| Median (IQR) | 0.420 (0.413-0.425) |
0.346 (0.323-0.363) |
22.5 (22.2-22.9) |
18.1 (16.7-18.9) |
0.24 (0.16-0.33) |
2.10 (1.72-2.48) |
0.83 (0.79-0.86) |
| Diabetic group | |||||||
| Mean (SD) [range] | 0.409 (0.009) [0.384-0.425] |
0.320 (0.033) [0.224-0.376] |
21.2 (1.0) [19.3-23.4] |
16.4 (1.9) [11.3-19.6] |
0.26 (0.10) [0.06-0.63] |
2.32 (0.59) [1.13-4.05] |
0.78 (0.09) [0.55-1.08] |
| Median (IQR) | 0.410 (0.405-0.415) |
0.325 (0.293-0.347) |
21.2 (20.5-21.9) |
16.2 (15.0-17.9) |
0.26 (0.19-0.31) |
2.27 (2.04-2.58) |
0.78 (0.72-0.84) |
| P valuec | <.001 | .009 | <.001 | <.001 | .28 | .01 | .12 |
a
A unitless measure.
b
After removal of decorrelation tail artifact.
c
For 2-tailed, 2-population heteroscedastic comparison between groups.