RT Journal Article
SR Electronic
T1 Brain Perfusion Measurements Using Multidelay Arterial Spin-Labeling Are Systematically Biased by the Number of Delays
JF American Journal of Neuroradiology
JO Am. J. Neuroradiol.
FD American Society of Neuroradiology
SP 1432
OP 1438
DO 10.3174/ajnr.A5717
VO 39
IS 8
A1 M. van der Thiel
A1 C. Rodriguez
A1 P. Giannakopoulos
A1 M.X. Burke
A1 R. Marc Lebel
A1 N. Gninenko
A1 D. Van De Ville
A1 S. Haller
YR 2018
UL http://www.ajnr.org/content/39/8/1432.abstract
AB BACKGROUND AND PURPOSE: Multidelay arterial spin-labeling is a promising emerging method in clinical practice. The effect of imaging parameters in multidelay arterial spin-labeling on estimated cerebral blood flow measurements remains unknown. We directly compared 3-delay versus 7-delay sequences, assessing the difference in the estimated transit time and blood flow.MATERIALS AND METHODS: This study included 87 cognitively healthy controls (78.7 ± 3.8 years of age; 49 women). We assessed delay and transit time–uncorrected and transit time–corrected CBF maps. Data analysis included voxelwise permutation-based between-sequence comparisons of 3-delay versus 7-delay, within-sequence comparison of transit time–uncorrected versus transit time–corrected maps, and average CBF calculations in regions that have been shown to differ.RESULTS: The 7-delay sequence estimated a higher CBF value than the 3-delay for the transit time–uncorrected and transit time–corrected maps in regions corresponding to the watershed areas (transit time–uncorrected = 27.62 ± 12.23 versus 24.58 ± 11.70 mL/min/100 g, Cohen's d = 0.25; transit time–corrected = 33.48 ± 14.92 versus 30.16 ± 14.32 mL/min/100 g, Cohen's d = 0.23). In the peripheral regions of the brain, the estimated delay was found to be longer for the 3-delay sequence (1.52408 ± 0.25236 seconds versus 1.47755 ± 0.24242 seconds, Cohen's d = 0.19), while the inverse was found in the center of the brain (1.39388 ± 0.22056 seconds versus 1.42565 ± 0.21872 seconds, Cohen's d = 0.14). Moreover, 7-delay had lower hemispheric asymmetry.CONCLUSIONS: The results of this study support the necessity of standardizing acquisition parameters in multidelay arterial spin-labeling and identifying basic parameters as a confounding factor in CBF quantification studies. Our findings conclude that multidelay arterial spin-labeling sequences with a high number of delays estimate higher CBF values than those with a lower number of delays.ASLarterial spin-labelingdCohen's dPLDpostlabeling delay