TY - JOUR
T1 - The QUASAR reproducibility study, Part II
T2 - Results from a multi-center Arterial Spin Labeling test-retest study
AU - Petersen, Esben Thade
AU - Mouridsen, Kim
AU - Golay, Xavier
N1 - Funding Information:
The authors would like to thank Philips Healthcare for establishing the connections between the participating sites and for the worldwide support during this study. This work was supported by the following grants and institutions: NMRC/0919/2004 (Singapore), The Swedish Research Council (Sweden), NIH NS054916, P41 RR015241, NIH (USA), EPSRC (UK).
PY - 2010/1/1
Y1 - 2010/1/1
N2 - Arterial Spin Labeling (ASL) is a method to measure perfusion using magnetically labeled blood water as an endogenous tracer. Being fully non-invasive, this technique is attractive for longitudinal studies of cerebral blood flow in healthy and diseased individuals, or as a surrogate marker of metabolism. So far, ASL has been restricted mostly to specialist centers due to a generally low SNR of the method and potential issues with user-dependent analysis needed to obtain quantitative measurement of cerebral blood flow (CBF). Here, we evaluated a particular implementation of ASL (called Quantitative STAR labeling of Arterial Regions or QUASAR), a method providing user independent quantification of CBF in a large test-retest study across sites from around the world, dubbed "The QUASAR reproducibility study". Altogether, 28 sites located in Asia, Europe and North America participated and a total of 284 healthy volunteers were scanned. Minimal operator dependence was assured by using an automatic planning tool and its accuracy and potential usefulness in multi-center trials was evaluated as well. Accurate repositioning between sessions was achieved with the automatic planning tool showing mean displacements of 1.87 ± 0.95 mm and rotations of 1.56 ± 0.66°. Mean gray matter CBF was 47.4 ± 7.5 [ml/100 g/min] with a between-subject standard variation SDb = 5.5 [ml/100 g/min] and a within-subject standard deviation SDw = 4.7 [ml/100 g/min]. The corresponding repeatability was 13.0 [ml/100 g/min] and was found to be within the range of previous studies.
AB - Arterial Spin Labeling (ASL) is a method to measure perfusion using magnetically labeled blood water as an endogenous tracer. Being fully non-invasive, this technique is attractive for longitudinal studies of cerebral blood flow in healthy and diseased individuals, or as a surrogate marker of metabolism. So far, ASL has been restricted mostly to specialist centers due to a generally low SNR of the method and potential issues with user-dependent analysis needed to obtain quantitative measurement of cerebral blood flow (CBF). Here, we evaluated a particular implementation of ASL (called Quantitative STAR labeling of Arterial Regions or QUASAR), a method providing user independent quantification of CBF in a large test-retest study across sites from around the world, dubbed "The QUASAR reproducibility study". Altogether, 28 sites located in Asia, Europe and North America participated and a total of 284 healthy volunteers were scanned. Minimal operator dependence was assured by using an automatic planning tool and its accuracy and potential usefulness in multi-center trials was evaluated as well. Accurate repositioning between sessions was achieved with the automatic planning tool showing mean displacements of 1.87 ± 0.95 mm and rotations of 1.56 ± 0.66°. Mean gray matter CBF was 47.4 ± 7.5 [ml/100 g/min] with a between-subject standard variation SDb = 5.5 [ml/100 g/min] and a within-subject standard deviation SDw = 4.7 [ml/100 g/min]. The corresponding repeatability was 13.0 [ml/100 g/min] and was found to be within the range of previous studies.
KW - Arterial Spin Labeling
KW - Cerebral blood flow
KW - Perfusion, Multi-center trial
KW - Reproducibility
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U2 - 10.1016/j.neuroimage.2009.07.068
DO - 10.1016/j.neuroimage.2009.07.068
M3 - Article
C2 - 19660557
AN - SCOPUS:70349966233
SN - 1053-8119
VL - 49
SP - 104
EP - 113
JO - NeuroImage
JF - NeuroImage
IS - 1
ER -