Table 1. Performance Evaluation of Two Bulk Motion Subtraction Methods.

	Percentage of FAZ signal remaining after subtraction*	Mean vessel density (coefficient of variation)	Vascular connectivity*	Flow SNR*	RMS contrast*
Original (No subtraction)	N/A	87% (4.4%)	0.920 ± 0.003	10.6 ± 1.1	0.051 ± 0.002
Median subtraction	11.9% ± 1.0%	88% (3.3%)	0.921 ± 0.006	16.0 ± 1.7	0.051 ± 0.002
Regression-based bulk motion subtraction	9.6% ± 0.8%	85% (0.9%)	0.926 ± 0.003	19.7 ± 1.8	0.060 ± 0.001
p-value**	0.0034	0.0081	0.1783	<0.01	<0.01

^*Mean ± standard error.

^**Values correspond to the comparison between the two subtraction methods; n = 8.