TY - JOUR
T1 - Improved cerebrospinal fluid flow measurements using phase contrast balanced steady-state free precession
AU - McCormack, Erin J.
AU - Egnor, Michael R.
AU - Wagshul, Mark E.
N1 - Funding Information:
We would like to thank the Dana Foundation and the Brainchild Foundation for financial support of this work, Philips Medical Systems for technical support and John J. Chen of the Department of Preventative Medicine at Stony Brook University Hospital for assistance with the statistical analysis.
Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2007/2
Y1 - 2007/2
N2 - We present a demonstration of phase contrast balanced steady-state free precession (PC-bSSFP) for measuring cerebrospinal fluid (CSF) flow in the brain and spine, and a comparison of measurements obtained with this technique to conventional phase contrast using incoherent gradient echoes (PC-GRE). With PC-GRE sequences, CSF images suffer from low signal-to-noise ratio (SNR), due to short repetition times required for adequate temporal resolution, and the long relaxation time of CSF. Furthermore, CSF flow is often nonlaminar, causing phase dispersion and signal loss in PC-GRE images. It is hypothesized that PC-bSSFP can improve CSF flow measurements with its high SNR and insensitivity to turbulent flow effects. CSF images acquired from the two techniques were compared in 13 healthy volunteers. Three measures were used to objectively evaluate the PC-bSSFP sequence: the CSF flow percentage, defined as the percentage of the total CSF region exhibiting pulsatile flow, net stroke volume and SNR. Images acquired with PC-bSSFP demonstrated pulsatile CSF flow in 35.8% (P<.005), 11.2% (P<.05) and 27.8% (P<.0005) more pixels than PC-GRE in the prepontine cistern, anterior and posterior cervical subarachnoid space (SAS), respectively. Likewise, measurements of stroke volume in these regions increased by 61.6% (P<.05), 16.8% (P<.001) and 48.3% (P<.0001), respectively. Similar comparisons in the aqueduct showed no statistical difference in stroke volumes between the two techniques (P=.5). The average gain in SNR was 3.3±1.7 (P<.001) in the prepontine cistern, 5.0±0.2 (P<.01) at the cervical level and 2.0±0.4 (P<.001) in the aqueduct in PC-bSSFP magnitude images over PC-GRE images. In addition to the obvious advantage of increased SNR, these results indicate that PC-bSSFP provides more complete measurements of CSF flow data than PC-GRE. PC-bSSFP can be used as a reliable technique for CSF flow quantification for the characterization of normal and altered intracranial CSF flow patterns.
AB - We present a demonstration of phase contrast balanced steady-state free precession (PC-bSSFP) for measuring cerebrospinal fluid (CSF) flow in the brain and spine, and a comparison of measurements obtained with this technique to conventional phase contrast using incoherent gradient echoes (PC-GRE). With PC-GRE sequences, CSF images suffer from low signal-to-noise ratio (SNR), due to short repetition times required for adequate temporal resolution, and the long relaxation time of CSF. Furthermore, CSF flow is often nonlaminar, causing phase dispersion and signal loss in PC-GRE images. It is hypothesized that PC-bSSFP can improve CSF flow measurements with its high SNR and insensitivity to turbulent flow effects. CSF images acquired from the two techniques were compared in 13 healthy volunteers. Three measures were used to objectively evaluate the PC-bSSFP sequence: the CSF flow percentage, defined as the percentage of the total CSF region exhibiting pulsatile flow, net stroke volume and SNR. Images acquired with PC-bSSFP demonstrated pulsatile CSF flow in 35.8% (P<.005), 11.2% (P<.05) and 27.8% (P<.0005) more pixels than PC-GRE in the prepontine cistern, anterior and posterior cervical subarachnoid space (SAS), respectively. Likewise, measurements of stroke volume in these regions increased by 61.6% (P<.05), 16.8% (P<.001) and 48.3% (P<.0001), respectively. Similar comparisons in the aqueduct showed no statistical difference in stroke volumes between the two techniques (P=.5). The average gain in SNR was 3.3±1.7 (P<.001) in the prepontine cistern, 5.0±0.2 (P<.01) at the cervical level and 2.0±0.4 (P<.001) in the aqueduct in PC-bSSFP magnitude images over PC-GRE images. In addition to the obvious advantage of increased SNR, these results indicate that PC-bSSFP provides more complete measurements of CSF flow data than PC-GRE. PC-bSSFP can be used as a reliable technique for CSF flow quantification for the characterization of normal and altered intracranial CSF flow patterns.
KW - CSF flow
KW - Cerebrospinal fluid (CSF)
KW - Hydrocephalus
KW - Phase contrast
KW - Steady-state free precession (SSFP)
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U2 - 10.1016/j.mri.2006.09.023
DO - 10.1016/j.mri.2006.09.023
M3 - Article
C2 - 17275611
AN - SCOPUS:33846493568
SN - 0730-725X
VL - 25
SP - 172
EP - 182
JO - Magnetic Resonance Imaging
JF - Magnetic Resonance Imaging
IS - 2
ER -