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PT  - JOURNAL ARTICLE
AU  - Wentland, A.L.
AU  - Wieben, O.
AU  - Korosec, F.R.
AU  - Haughton, V.M.
TI  - Accuracy and Reproducibility of Phase-Contrast MR Imaging Measurements for CSF Flow
AID  - 10.3174/ajnr.A2039
DP  - 2010 Aug 01
TA  - American Journal of Neuroradiology
PG  - 1331--1336
VI  - 31
IP  - 7
4099  - http://www.ajnr.org/content/31/7/1331.short
4100  - http://www.ajnr.org/content/31/7/1331.full
SO  - Am. J. Neuroradiol.2010 Aug 01; 31
AB  - BACKGROUND AND PURPOSE: PCMR, widely used for the evaluation of blood flow, has been adopted for the assessment of cerebrospinal fluid flow in a variety of disorders. The purpose of this study was to evaluate the accuracy and reproducibility of 2 fast PCMR techniques for measuring CSF flow. MATERIALS AND METHODS: Velocities were calculated from RPC and CPC images of fluid flowing in a tube at a constant velocity. Error and the COV were computed for average and peak velocities. Additionally, measurements of sinusoidally fluctuating flow and of CSF flow in 5 healthy volunteers were acquired with the RPC and CPC acquisitions. RESULTS: For constant velocity experiments, error for the RPC and CPC acquisitions averaged +1.15% and +8.91% and COVs averaged 1.29% and 3.01%, respectively. For peak velocities of ≥12.6 cm/s, error with RPC or CPC ranged from −33.3% to −36.9% and COVs were 0%–4% for RPC and 1%–7% for CPC. For peak velocities of ≤6.4 cm/s, RPC and CPC overestimated velocity by &amp;gt;250%. For fluctuating flow, both acquisitions showed similar flow patterns. In volunteer studies, peak systolic and diastolic velocities were not significantly different. CONCLUSIONS: The RPC and CPC sequences measure velocities on the order of CSF flow with an average error of ≥9%. The 2 techniques significantly overestimate peak velocities &amp;lt;6.4 cm/s, with maximum errors of 209% and 276% and maximum COVs of 100% and 73% for the RPC and CPC sequences, respectively. Measurements of CSF velocities in human volunteers and of sinusoidally fluctuating phantom velocities did not differ significantly between the 2 techniques. COVcoefficient of variationCPCCartesian-based phase contrastPCMRphase-contrast MR imagingQAquality assuranceRBWreceiver bandwidthRPCradially sampled phase contrastSNRsignal intensity–to-noise ratioVENCvelocity encodingvpsviews per segment