Department of Radiology, Graduate School of Medicine, University of Tokyo, Bunkyo-ku, Tokyo, Japan.
J Magn Reson Imaging. 2013 Nov;38(5):1283-91. doi: 10.1002/jmri.24038. Epub 2013 Jan 31.
To evaluate the effects of inter-scanner variability (bias) and of scanner upgrade on longitudinal changes in regional gray matter volume.
A total of 215 normal subjects were scanned twice, at an interval of approximately 1 year, using two 3.0 Tesla (T) scanners of the exact same model. Both scanners were simultaneously upgraded during the study period. The subjects were divided into four groups according to the combination of scanners used at the two time points. Using VBM, we evaluated longitudinal changes in regional gray matter volume in each group and the effects of scanner upgrade on longitudinal changes.
The use of different scanners at two time points significantly influenced longitudinal changes in regional gray matter volume. Regional gray matter volumes were relatively stable within the same scanner, but significantly different between the two scanners. Scanner upgrade had effects comparable to those of using different scanners at the two time points.
The results of our study indicate that, even with scanners of the exact same model, the use of different scanners at different time points significantly influences longitudinal morphometric results, and that scanner upgrade has effects comparable to those of using different scanners at different time points.
评估扫描仪间变异性（偏差）以及扫描仪升级对区域灰质体积纵向变化的影响。
共 215 名正常受试者，使用完全相同型号的两台 3.0T 扫描仪，在大约 1 年的时间内进行了两次扫描。在研究期间，两台扫描仪同时进行了升级。根据两次扫描使用的扫描仪组合，将受试者分为四组。使用 VBM，我们评估了每组的区域灰质体积的纵向变化以及扫描仪升级对纵向变化的影响。
两次扫描使用不同的扫描仪显著影响区域灰质体积的纵向变化。同一扫描仪内的区域灰质体积相对稳定，但在两台扫描仪之间存在显著差异。扫描仪升级的效果与两次扫描使用不同扫描仪的效果相当。
本研究结果表明，即使使用完全相同型号的扫描仪，在不同时间点使用不同的扫描仪也会显著影响纵向形态计量结果，并且扫描仪升级的效果与在不同时间点使用不同扫描仪的效果相当。
