Analyses of Aqueductal Area and Cerebrospinal Fluid Flow-Velocity in Normal Pressure Hydrocephalus

Abstract

In this study, we assessed cross-sectional area of the aqueduct and the cerebrospinal fluid（CSF）flow-velocity in normal pressure hydrocephalus（NPH）using cine magnetic resonance imaging（MRI）. On a 1.5-T MRI, ECG-synchronized phase-contrast cine-MRI technique was used to measure the quantitative CSF flow-velocity in the aqueduct in patient with NPH（n=24）, atrophic ventricular dilation（VD,n=19）and healthy volunteers（control, n = 25）. The aqueductal area was measured using high-resolution T₂-weighted image in each group. The aqueductal CSF flow-velocity amplitude was significantly larger in the NPH group（19.68 ± 10.98 cm/s）than in the VD group（6.67 ± 3.88, P < 0.001）and the control group（10.98 ± 4.26, P = 0.018）. The aquedutal area was significantly lager in the NPH group（0.08 ± 0.04 cm²）than in the control group（0.03 ± 0.01, P < 0.001）, but not significantly different between the NPH and VD groups（0.08 ± 0.05, P = 1.000）. Aqueductal CSF flow-velocity in NPH increases, despite the aqueductal area increases.