The Difference in Repeatability of Automated Superficial Retinal Vessel Density according to the Measurement Area Using OCT Angiography

Table 2

Comparisons of the vascular density, perfusion density, and foveal avascular zone metrics between 3 × 3 mm and 6 × 6 mm scans.

	Mean values of two 3 × 3 mm scans	Mean values of two 6 × 6 mm scans	value
Vessel density
Total area (mean ± SD, mm^−1)	20.77 ± 1.80	18.53 ± 0.60
Center (mean ± SD, mm^−1)	10.53 ± 8.37	9.93 ± 6.53	<0.001
Inner average (mean ± SD, mm^−1)	22.06 ± 1.75	18.65 ± 0.92	<0.001
Perfusion density
Total area (mean ± SD)	0.359 ± 0.013	0.434 ± 0.015
Center (mean ± SD)	0.171 ± 0.017	0.196 ± 0.028	<0.001
Inner average (mean ± SD)	0.382 ± 0.013	0.422 ± 0.022	<0.001
Foveal avascular area
Area (mean ± SD, mm^2)	0.245 ± 0.115	0.280 ± 0.120	0.484
Perimeter (mean ± SD, mm)	2.269 ± 0.564	2.176 ± 0.581	0.018
Circularity (mean ± SD)	0.652 ± 0.088	0.704 ± 0.098	<0.001

SD, standard deviation. The p value was obtained using a paired t-test. Boldface numbers indicate statistically significant differences at .