Table 2.

Post hoc comparisons of vascular and CSF flow results in the four groups.

	HEVs vs. aMCI	HEVs vs. AD	HEVs vs. NPH	aMCI vs. AD	aMCI vs. NPH	AD vs. NPH
tCBF	0.01	NS	NS	NS	<0.01	0.06
API	<0.05	NS	NS	NS	NS	NS
Arterial pulse volume	<0.01	NS	NS	0.06	<0.01	NS
VBF	<0.01	NS	NS	NS	<0.01	NS
AV stroke volume	<0.01	NS	NS	NS	0.05	NS
AV delay	<0.01	<0.01	<0.01	NS	NS	NS
Aqueductal stroke volume	NS	NS	<0.05	NS	NS	<0.05

HEVs: Healthy elderly volunteers; aMCI: patients with amnesic mild cognitive impairment; AD: patients with Alzheimer's disease; NPH: patients with normal pressure hydrocephalus; tCBF: total cerebral arterial blood flow; API: arterial pulsatility index; VBF: venous blood flow; AV: arteriovenous. P values in bold are statistically significant. P values on a grey background are close to statistical significance. NS: not significant.