Department of Radiology, University of Iowa, 500 Newton Road, Iowa City, IA 52242-1000, USA.
Brain Connect. 2012;2(6):345-55. doi: 10.1089/brain.2012.0112.
A number of studies are now collecting diffusion tensor imaging (DTI) data across sites. While the reliability of anatomical images has been established by a number of groups, the reliability of DTI data has not been studied as extensively. In this study, five healthy controls were recruited and imaged at eight imaging centers. Repeated measures were obtained across two imaging protocols allowing intra-subject and inter-site variability to be assessed. Regional measures within white matter were obtained for standard rotationally invariant measures: fractional anisotropy, mean diffusivity, radial diffusivity, and axial diffusivity. Intra-subject coefficient of variation (CV) was typically <1% for all scalars and regions. Inter-site CV increased to ~1%-3%. Inter-vendor variation was similar to inter-site variability. This variability includes differences in the actual implementation of the sequence.
目前，许多研究正在各个站点收集扩散张量成像（DTI）数据。尽管许多小组已经证实了解剖图像的可靠性，但 DTI 数据的可靠性尚未得到广泛研究。在这项研究中，招募了五名健康对照者，并在八个成像中心进行了成像。获得了两种成像方案的重复测量，以评估个体内和站点间的可变性。获得了标准旋转不变量的白质内区域测量值：各向异性分数、平均扩散率、径向扩散率和轴向扩散率。所有标量和区域的个体内变异系数（CV）通常<1%。站点间 CV 增加到约 1%-3%。供应商间的变化与站点间的变化相似。这种可变性包括序列实际实现方式的差异。
