A Validation Study of Multicenter Diffusion Tensor Imaging: Reliability of Fractional Anisotropy and Diffusivity Values
A Validation Study of Multicenter Diffusion Tensor Imaging: Reliability of Fractional Anisotropy and Diffusivity Values
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DOI：
10.3174/ajnr.a2844
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发表时间：
2012-04-01
影响因子：
3.5
通讯作者：
Fisher, E.
中科院分区：
文献类型：
--
作者：
Fox, R. J.;Sakaie, K.;Fisher, E.
背景和目的：弥散张量成像（DTI）正越来越多地被用作研究神经系统疾病组织损伤的一种手段。我们的目的是探讨不同的MR成像磁铁和platforms.MATERIALS和METHODS：两名健康志愿者进行了DTI的5个31 MR成像扫描仪（3三重和2信号）之间的可比性的措施，通过使用匹配的33 noncollinear扩散方向脉冲序列。在每名受试者中，在单个图像集上绘制了总共16个白色物质（胼胝体、心室周和深层白色物质）和灰质（皮质和深灰色）感兴趣区域，然后与其他图像进行配准。计算每个ROI内的平均FA、ADC以及纵向和横向扩散率。一致性相关性通过比较5个磁铁中的每一个的ROI DTI值得出：FA的平均一致性为0.96;纵向和横向扩散系数，它是0.93;和ADC，它是0.88。所有DTI测量的平均扫描-再扫描一致性为0.96-0.97。平台内的一致性相关性，在一般情况下，优于平台之间的所有DTI措施（平均一致性为0.96）。结论：我们发现，3 T磁铁和高角分辨率脉冲序列产生了可比的DTI测量在不同的MR成像磁铁和平台。我们的研究结果表明，FA是最具可比性的措施在磁铁，其次是个人的扩散率。不同磁体之间DTI测量的可比性支持使用DTI作为结果测量的多中心临床试验的可行性。
BACKGROUND AND PURPOSE: DTI is increasingly being used as a measure to study tissue damage in several neurologic diseases. Our aim was to investigate the comparability of DTI measures between different MR imaging magnets and platforms.MATERIALS AND METHODS: Two healthy volunteers underwent DTI on five 31 MR imaging scanners (3 Trios and 2 Signas) by using a matched 33 noncollinear diffusion-direction pulse sequence. Within each subject, a total of 16 white matter (corpus callosum, periventricular, and deep white matter) and gray matter (cortical and deep gray) ROIs were drawn on a single image set and then were coregistered to the other images. Mean FA, ADC, and longitudinal and transverse diffusivities were calculated within each ROI. Concordance correlations were derived by comparing ROI DTI values among each of the 5 magnets.RESULTS: Mean concordance for FA was 0.96; for both longitudinal and transverse diffusivities, it was 0.93; and for ADC, it was 0.88. Mean scan-rescan concordance was 0.96-0.97 for all DTI measures. Concordance correlations within platforms were, in general, better than those between platforms for all DTI measures (mean concordance of 0.96).CONCLUSIONS: We found that a 3T magnet and high-angular-resolution pulse sequence yielded comparable DTI measurements across different MR imaging magnets and platforms. Our results indicate that FA is the most comparable measure across magnets, followed by individual diffusivities. The comparability of DTI measures between different magnets supports the feasibility of multicentered clinical trials by using DTI as an outcome measure.