Precision of the CASL-perfusion MRI technique for the measurement of cerebral blood flow in whole brain and vascular territories

• Published in: Journal of magnetic resonance imaging 2003-12, Vol.18 (6), p.649-655
• Main Authors: Floyd, Thomas F., Ratcliffe, Sarah J., Wang, Jiongjiong, Resch, Brooke, Detre, John A.
• Format: Article
• Language: English
• Subjects: Adult; Analysis of Variance; arterial spin tagging; brain; Brain - blood supply; Brain - physiology; cerebral blood flow; Cerebrovascular Circulation - physiology; Female; Humans; Magnetic Resonance Angiography - methods; magnetic resonance imaging; Male; precision; Regional Blood Flow - physiology; repeatability; reproducibility; Sensitivity and Specificity; Time Factors
• ISSN: 1053-1807; 1522-2586
• DOI: 10.1002/jmri.10416

Purpose To analyze the precision of cerebral blood flow (CBF) measurements made with continuous arterial spin labeling(CASL) perfusion magnetic resonance imaging (MRI) over experimentally relevant intervals. Materials and Methods CASL perfusion MRI measurements of CBF on a 1.5‐T GE Signa magnet were repeated in young healthy male and female subjects at one hour and one week. Precision of the measurement was evaluated at both time intervals. Results CASL perfusion MRI measurements of CBF yielded within‐subject coefficients of variation (wsCV) of 5.8% for global and 13% for individual vascular regions when measurements were repeated within one hour. Differences in these values represent the error in post‐processing. Global and regional CBF measurements over one week yielded wsCVs of 13% and 14%, respectively. At one week, error secondary to physiologic variability affected global and regional measurements to the same degree and masked the software post‐processing error seen at one hour. The magnitude of the difference in repeated measures correlated with the magnitude of the measurement. Conclusion CASL perfusion MRI CBF measurements are accurate and precise. Variability over longer periods of time appears attributable to physiologic factors. Repeatability of the CASL measurement is sensitive to the magnitude of the measurement. This should be taken into account when studies requiring repeated measures involve subjects with significant variability in CBF. J. Magn. Reson. Imaging 2003;18:649–655. © 2003 Wiley‐Liss, Inc.