Multi-system repeatability and reproducibility of apparent diffusion coefficient measurement using an ice-water phantom
Article first published online: 28 SEP 2012
Copyright © 2012 Wiley Periodicals, Inc.
Journal of Magnetic Resonance Imaging
Volume 37, Issue 5, pages 1238–1246, May 2013
How to Cite
Malyarenko, D., Galbán, C. J., Londy, F. J., Meyer, C. R., Johnson, T. D., Rehemtulla, A., Ross, B. D. and Chenevert, T. L. (2013), Multi-system repeatability and reproducibility of apparent diffusion coefficient measurement using an ice-water phantom. J. Magn. Reson. Imaging, 37: 1238–1246. doi: 10.1002/jmri.23825
- Issue published online: 17 APR 2013
- Article first published online: 28 SEP 2012
- Manuscript Accepted: 16 AUG 2012
- Manuscript Received: 22 MAR 2012
- National Institutes of Health. Grant Numbers: P01-CA85878, U01-CA166104, P50-CA93990, R01CA136892, P01CA087634, SAIC 29XS161, T32 EB005172
- quality control;
- gradient nonlinearity
To determine quantitative quality control procedures to evaluate technical variability in multi-center measurements of the diffusion coefficient of water as a prerequisite to use of the biomarker apparent diffusion coefficient (ADC) in multi-center clinical trials.
Materials and Methods:
A uniform data acquisition protocol was developed and shared with 18 participating test sites along with a temperature-controlled diffusion phantom delivered to each site. Usable diffusion weighted imaging data of ice water at five b-values were collected on 35 clinical MRI systems from three vendors at two field strengths (1.5 and 3 Tesla [T]) and analyzed at a central processing site.
Standard deviation of bore-center ADCs measured across 35 scanners was <2%; error range: −2% to +5% from literature value. Day-to-day repeatability of the measurements was within 4.5%. Intra-exam repeatability at the phantom center was within 1%. Excluding one outlier, inter-site reproducibility of ADC at magnet isocenter was within 3%, although variability increased for off-center measurements. Significant (>10%) vendor-specific and system-specific spatial nonuniformity ADC bias was detected for the off-center measurement that was consistent with gradient nonlinearity.
Standardization of DWI protocol has improved reproducibility of ADC measurements and allowed identifying spatial ADC nonuniformity as a source of error in multi-site clinical studies. J. Magn. Reson. Imaging 2013;37:1238–1246. © 2012 Wiley Periodicals, Inc.