Nonlinear distortion correction of diffusion MR images improves quantitative DTI measurements in glioblastoma.
Nonlinear distortion correction of diffusion MR images improves quantitative DTI measurements in glioblastoma.
复制标题
扩散 MR 图像的非线性畸变校正改善了胶质母细胞瘤的定量 DTI 测量。
DOI：
10.1007/s11060-013-1320-2
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发表时间：
2014
影响因子：
3.9
通讯作者：
Ellingson,BenjaminM
中科院分区：
文献类型：
--
作者：
Woodworth,DavisC;Pope,WhitneyB;Liau,LindaM;Kim,HyunJ;Lai,Albert;Nghiemphu,PhioanhL;Cloughesy,TimothyF;Ellingson,BenjaminM
本研究的目的是使用回顾性非线性失真校正技术，并评估GBM肿瘤内和周围感兴趣区域的DTI指标变化。共24例经组织学证实的GBM患者术前进行了20个方向的DTI扫描。检查畸变校正前后正常组织表观扩散系数（ADC）和各向异性分数（FA）的变化。对比增强和T2/FLAIR ROI中ADC和FA的平均值、中位数和方差的变化也在有和没有失真校正的情况下进行了检查。结果表明，畸变校正后正常组织ADC和FA的受试者内标准差均降低（P< 0.0001）。畸变校正后，T1+C和T2 ROI的FA均值和中位数均降低（P< 0.017），而ADC均值和中位数除T1+C ROI的ADC中位数外无显著变化（P= 0.0054）。经畸变校正后，肿瘤ROI中ADC和FA值的受试者内SD发生显著变化，Bland-Altman分析表明，这些受试者内SD的偏倚和偏倚的SD均大于均值和中位数项。此外，发现T1+C ROI、ADCL（低高斯平均值）以及ADCH（高高斯平均值）ADC值直方图的双高斯拟合曲线的平均值随失真校正而显著变化（ADCL P= 0.0045，ADCH P = 0.0370）。非线性失真校正更好地对齐DTI和解剖扫描之间的神经解剖结构，并显着改变GBM患者的肿瘤ROI内的值的测量。
The purpose of this study was to use a retrospective nonlinear distortion correction technique and evaluate the changes in DTI metrics in areas of interest in and around GBM tumors. A total of 24 histologically confirmed GBM patients with pre-operative 20-direction DTI scans were examined. Variability in apparent diffusion coefficient (ADC) and fractional anisotropy (FA) in normal tissue before and after distortion correction were examined. Changes in mean, median and variance of ADC and FA in contrast enhancing and T2/FLAIR ROIs were also examined with and without distortion correction. Results suggest the intra-subject SDs of ADC and FA decreased in normal tissue after the application of distortion correction (P< 0.0001). FA mean and median values decreased after distortion correction in both T1+C and T2 ROIs (P< 0.017), while ADC mean and median values did not significantly change except for the median ADC in T1+C ROIs (P= 0.0054). The intra-subject SD of ADC and FA values in tumor ROIs changed significantly with distortion correction, and Bland–Altman analysis indicated that the bias and the SD of the bias of these intra-subject SDs were larger than those of the mean and median terms. Additionally, the means of the two curves of a double Gaussian fit to the histogram of ADC values from T1+C ROIs, ADCL(mean of lower Gaussian) as well as ADCH(mean of the higher Gaussian) were found to change significantly with distortion correction (P= 0.0045 for ADCLandP= 0.0370 for ADCH). Nonlinear distortion correction better aligns neuro-anatomical structures between DTI and anatomical scans, and significantly alters the measurement of values within tumor ROIs for GBM patients.