Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio, USA.
Department of Radiology, Case Western Reserve University, Cleveland, Ohio, USA.
Magn Reson Med. 2017 Oct;78(4):1452-1457. doi: 10.1002/mrm.26509. Epub 2016 Oct 27.
The purpose of this study was to evaluate accuracy and repeatability of T and T estimates of a MR fingerprinting (MRF) method using the ISMRM/NIST MRI system phantom.
The ISMRM/NIST MRI system phantom contains multiple compartments with standardized T , T , and proton density values. Conventional inversion-recovery spin echo and spin echo methods were used to characterize the T and T values in the phantom. The phantom was scanned using the MRF-FISP method over 34 consecutive days. The mean T and T values were compared with the values from the spin echo methods. The repeatability was characterized as the coefficient of variation of the measurements over 34 days.
T and T values from MRF-FISP over 34 days showed a strong linear correlation with the measurements from the spin echo methods (R = 0.999 for T ; R = 0.996 for T ). The MRF estimates over the wide ranges of T and T values have less than 5% variation, except for the shortest T relaxation times where the method still maintains less than 8% variation.
MRF measurements of T and T are highly repeatable over time and across wide ranges of T and T values. Magn Reson Med 78:1452-1457, 2017. © 2016 International Society for Magnetic Resonance in Medicine.
本研究旨在评估使用 ISMRM/NIST MRI 系统体模的磁共振指纹成像(MRF)方法的 T1 和 T2 估计的准确性和可重复性。
ISMRM/NIST MRI 系统体模包含具有标准化 T1、T2 和质子密度值的多个腔室。采用反转恢复自旋回波和自旋回波方法来表征体模中的 T1 和 T2 值。使用 MRF-FISP 方法对体模进行了 34 天的连续扫描。将平均 T1 和 T2 值与自旋回波方法的测量值进行比较。将测量值的可重复性表示为 34 天内的变异系数。
34 天内的 MRF-FISP 的 T1 和 T2 值与自旋回波方法的测量值具有很强的线性相关性(T1:R2=0.999;T2:R2=0.996)。在广泛的 T1 和 T2 值范围内,MRF 估计值的变化小于 5%,除了最短的 T1 弛豫时间外,该方法仍保持小于 8%的变化。
MRF 对 T1 和 T2 的测量在时间上和在广泛的 T1 和 T2 值范围内具有高度的可重复性。磁共振医学 78:1452-1457,2017。© 2016 国际磁共振学会。