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Multi-vendor reliability of arterial spin labeling perfusion MRI using a near-identical sequence: Implications for multi-center studies

Henri J.M.M. Mutsaerts, Matthias J.P. van Osch, Fernando O. Zelaya, Danny J.J. Wang, Wibeke Nordhøy, Yi Wang, Stephen Wastling, Maria A. Fernandez-Seara, E.T. Petersen, Francesca B. Pizzini, Sameeha Fallatah, Jeroen Hendrikse (+6 others)
2015 NeuroImage  
A main obstacle that impedes standardized clinical and research applications of arterial spin labeling (ASL), is the substantial differences between the commercial implementations of ASL from major MRI vendors. In this study, we compare a single identical 2D gradient-echo EPI pseudo-continuous ASL (PCASL) sequence implemented on 3T scanners from three vendors (General Electric Healthcare, Philips Healthcare and Siemens Healthcare) within the same center and with the same subjects. Material and
more » ... ethods: Fourteen healthy volunteers (50% male, age 26.4 ± 4.7 years) were scanned twice on each scanner in an interleaved manner within 3 h. Because of differences in gradient and coil specifications, two separate studies were performed with slightly different sequence parameters, with one scanner used across both studies for comparison. Reproducibility was evaluated by means of quantitative cerebral blood flow (CBF) agreement and inter-session variation, both on a region-of-interest (ROI) and voxel level. In addition, a qualitative similarity comparison of the CBF maps was performed by three experienced neuro-radiologists. Results: There were no CBF differences between vendors in study 1 (p N 0.1), but there were CBF differences of 2-19% between vendors in study 2 (p b 0.001 in most gray matter ROIs) and 10-22% difference in CBF values obtained with the same vendor between studies (p b 0.001 in most gray matter ROIs). The inter-vendor inter-session variation was not significantly larger than the intra-vendor variation in all (p N 0.1) but one of the ROIs (p b 0.001). Conclusion: This study demonstrates the possibility to acquire comparable cerebral CBF maps on scanners of different vendors. Small differences in sequence parameters can have a larger effect on the reproducibility of ASL than hardware or software differences between vendors. These results suggest that researchers should strive to employ identical labeling and readout strategies in multi-center ASL studies.
doi:10.1016/j.neuroimage.2015.03.043 pmid:25818685 fatcat:gb6jgstz7nen5ehs7nvschwwoe

Objective Bayesian fMRI analysis—a pilot study in different clinical environments

Joerg Magerkurth, Laura Mancini, William Penny, Guillaume Flandin, John Ashburner, Caroline Micallef, Enrico De Vita, Pankaj Daga, Mark J. White, Craig Buckley, Adam K. Yamamoto, Sebastien Ourselin (+3 others)
2015 Frontiers in Neuroscience  
Acknowledgments We would like to thank The 3rd Floor Writing Club of the UCL Brain Repair and Rehabilitation department for comments on the paper (including Suzan Prejawa, Ruth Oliver, Sameeha Fallatah  ... 
doi:10.3389/fnins.2015.00168 pmid:26029041 pmcid:PMC4428130 fatcat:7l6ovzeuebgaphtnm6wfptl62u