Table 4 Bland–Altman analysis and paired t-tests show the level of agreement between OCTAVA and in-built commercial OCTA software packages for measuring retinal vessel area density, vessel length, and foveal avascular zone metrics.
From: Towards standardising retinal OCTÂ angiography image analysis with open-source toolbox OCTAVA
Instrument and participant count | Metric | OCTAVA | In-built software | Bland–Altman analysis | Spearman correlation (p-value) | |||||
|---|---|---|---|---|---|---|---|---|---|---|
Mean (SD) | Mean (SD) | Mean | SD | Lower LA | Upper LA | tstat | p-value | |||
Cirrus 5000 n = 32 | Total VAD [%] | 36.5 (1.9) | 35.6 (2.1) |  +0.9 | 1.72 | -2.4 |  +4.3 |  +3.1 |  < 0.01 | 0.630 (p < 0.01) |
Parafoveal VAD [%] | 37.4 (2.2) | 37.9 (2.1) | -0.5 | 1.77 | -3.9 |  +3.0 |  -1.5 |  < 0.01 | 0.667 (p < 0.01) | |
Foveal VAD [%] | 19.1 (4.2) | 17.5 (4.5) |  +1.6 | 0.17 |   +0.1 |  +1.0 |  +21.6 |  < 0.01 | 0.905 (p < 0.01) | |
Total VL [mm] | 185 (11) | 183 (10) |  +2 | 7.5 | -12.8 |  +16.5 |  +1.4 | 0.17 | 0.724 (p < 0.01) | |
Parafoveal VL [mm] | 132.5 (8.6) | 152.3 (7.9) | -19.8 | 5.5 | -30.5 | -8.9 | -20.3 |  < 0.01 | 0.792 (p < 0.01) | |
Foveal VL [mm] | 7.7 (5.6) | 8.4 (2.1) | -0.7 | 5.5 | -11.4 |  +10.0 |  -0.7 | 0.48 | 0.388 (p = 0.28) | |
FAZA [mm2] | 0.275 (0.107) | 0.275 (0.11) |  -0.001 | 0.019 | -0.04 |  +0.04 |  -2.7 | 0.79 | 0.923 (p < 0.01) | |
FAZ perimeter [mm] | 2.29 (0.52) | 2.17 (0.43) |  +0.11 | 0.28 | -0.43 |  +0.66 |  +2.3 | 0.03 | 0.799 (p < 0.01) | |
FAZ circularity | 0.67 (0.15) | 0.71 (0.07) | -0.04 | 0.11 | -0.25 |  +0.16 |  -2.3 | 0.03 | 0.708 (p < 0.01) | |
Revo NX 130 n = 30 | Total VAD [%] | 31.9 (3.7) | 40.3 (1.2) | -8.3 | 3.4 | -15.4 | -1.3 |  -12.7 |  < 0.01 | 0.192 (p = 0.31) |
Total VL [mm] | 178 (20) | 208 (11) | -30 | 19 | -68 |  +6 |  -8.9 |  < 0.01 | 0.406 (p = 0.03) | |
FAZA [mm2] | 0.322 (0.144) | 0.342 (0.163) | -0.02 | 0.04 | -0.091 |  +0.051 |  -3.0 |  < 0.01 | 0.955 (p < 0.01) | |
FAZ perimeter [mm] | 2.28 (0.59) | 2.48 (0.69) | -0.20 | 0.38 | -0.95 |  +0.55 |  -2.9 |  < 0.01 | 0.843 (p < 0.01) | |
FAZ circularity | 0.77 (0.17) | 0.58 (0.097) |  +0.20 | 0.19 |  -0.17 |  +0.56 | +5.75 |  < 0.01 | 0.176 (p = 0.35) | |
RTVue-XR n = 31 | Total VAD [%] | 30 (3) | 50 (2) | -20 | 1.7 | -23.7 | -17.1 | -43.6 |  < 0.01 | 0.705 (p < 0.01) |
FAZA [mm2] | 0.213 (0.111) | 0.212 (0.11) |  +0.001 | 0.015 | -0.027 |  +0.030 |  +0.5 | 0.63 | 0.992 (p < 0.01) | |
FAZ perimeter [mm] | 2.09 (0.7) | 1.77 (0.49) |  +0.32 | 0.37 | -0.40 |  +1.04 |  +4.8 |  < 0.01 | 0.884 (p < 0.01) | |
FD-300 [%] | 34.3 (4) | 50 (4) |  -15.6 | 2.1 | -19.7 | -116 |  -42.2 |  < 0.01 | 0.783 (p < 0.01) | |
