Table 3.

Comparing hemodynamics based on clinical response (>50% reduction in frequency).

	Responder n = 6	Non-responder n = 12	p-value
Change in MCA velocity, cm/s	−6.0 (−12.4 to −1.1)	6.6 (1.7 to 15.4)	0.007
Change in PCA velocity, cm/s	−8.9 (−10.3 to −6.9)	1.6 (−5.1 to 15.1)	0.04
Change in MCA PI	0.02 (−0.07 to 0.04)	0.03 (−0.06 to 0.05)	0.92
Change in PCA PI	0.23 (0.18 to 0.29)	0.04 (0.00 to 0.12)	0.02
Autoregulation
Change in MCA Mx index	0.00 (−0.18 to 0.08)	0.08 (−0.07 to 0.22)	0.26
Change in PCA Mx index	0.03 (−0.07 to 0.10)	0.00 (−0.12 to 0.09)	0.75
Cerebrovascular reactivity
Change in MCA CVR	0.5 (−0.7 to 1.8)	−0.3 (−1.6 to 1.8)	0.60
Change in PCA CVR	−0.5 (−1.5 to −0.3)	−0.5 (−1.3 to 3.2)	0.23

Patients who experienced > 50% reduction in the number of headache days per month were categorized as responders. All reported variables are continuous but not normally distributed, so medians and interquartile ranges were reported. The change in each parameter was calculated by subtracting the final value from the baseline value. p-values were calculated by Wilcoxon-Mann–Whitney test. MCA indicates middle cerebral artery. PCA indicates posterior cerebral artery. PI indicates pulsatility index. CVR indicates cerebrovascular reactivity.