Evaluation of non-monoexponential diffusion models for hepatocellular carcinoma using b values up to 2000 s/mm2: A short-term repeatability study
Evaluation of non-monoexponential diffusion models for hepatocellular carcinoma using b values up to 2000 s/mm2: A short-term repeatability study
复制标题
使用高达 2000 s/mm(2) 的 b 值评估肝细胞癌的非单指数扩散模型：一项短期重复性研究
DOI：
10.1002/jmri.26563
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发表时间：
2019-07-01
影响因子：
4.4
通讯作者：
Zhu, Yue-Min
中科院分区：
文献类型：
--
作者：
Kuai, Zi-Xiang;Sang, Xi-Qiao;Zhu, Yue-Min
背景非单指数扩散模型越来越多地用于肝细胞癌（HCC）的定性和疗效评价。但是模型的拟合质量和参数的可重复性还没有被评估为HCC。目的评价峰度、拉伸指数和统计模型在b值高达2000 s/mm（2）的情况下用于HCC扩散加权成像（DWI）的拟合质量和可重复性。研究类型前瞻性。人群18例HCC患者。在3.0 T下采集场强/序列常规和DW图像（B = 0、200、500、1000、1500、2000 s/mm（2））。评估根据每个病变的感兴趣区域（ROI）计算峰度、拉伸指数和统计模型的参数。统计检验通过比较不同模型之间ROI平均数据的拟合残差，使用配对t检验或Wilcoxon秩和检验来评价拟合质量。使用内变异系数（WCV）、组内相关系数（ICC）和95% Bland-Altman一致性限（BA-LA）评估ROI体素数据中值处拟合参数的重复性。参照ICC和WCV值，将重复性分为4个等级：优、良、可接受和差。结果三种模型中，拉伸指数模型对HCC的拟合效果最好（P < 0.05），统计模型的拟合残差最大（P < 0.05）。峰度模型K值的重复性极好（ICC 0.915; WCV 8.79%），而拉伸模型的分布扩散系数（DDC）的重复性刚刚好（ICC 0.477; WCV 27.83%）。其他扩散相关参数的重复性良好。数据结论从模型拟合度和可重复性考虑，峰度模型和拉伸指数模型是描述肝细胞癌DW信号的首选模型。技术功效：第2阶段J. Magn. Reson。Imaging 2019;50：297-304.
Background Non-monoexponential diffusion models are being used increasingly for the characterization and curative effect evaluation of hepatocellular carcinoma (HCC). But the fitting quality of the models and the repeatability of their parameters have not been assessed for HCC. Purpose To evaluate kurtosis, stretched exponential, and statistical models for diffusion-weighted imaging (DWI) of HCC, using b-values up to 2000 s/mm(2), in terms of fitting quality and repeatability. Study Type Prospective. Population Eighteen patients with HCC. Field Strength/Sequence Conventional and DW images (b = 0, 200, 500, 1000, 1500, 2000 s/mm(2)) were acquired at 3.0T. Assessment The parameters of the kurtosis, stretched exponential, and statistical models were calculated on regions of interest (ROIs) of each lesion. Statistical Tests The fitting quality was evaluated through comparing the fitting residuals produced on the average data of ROI between different models using a paired t-test or Wilcoxon rank-sum test. Repeatability of the fitted parameters at the median values on the voxelwise data of ROI was assessed using the within coefficient of variation (WCV), the intraclass correlation coefficient (ICC), and the 95% Bland-Altman limits of agreements (BA-LA). The repeatability was divided into four levels: excellent, good, acceptable, and poor, referring to the values of ICC and WCV. Results Among three models, the stretched exponential model provided the best fit to HCC (P < 0.05), whereas the statistical model produced the largest fitting residuals (P < 0.05). The repeatability of K from the kurtosis model was excellent (ICC 0.915; WCV 8.79%), while the distributed diffusion coefficient (DDC) from the stretched model was just acceptable (ICC 0.477; WCV 27.83%). The repeatability was good for other diffusion-related parameters. Data Conclusion Considering the model fit and repeatability, the kurtosis and stretched exponential models are the preferred models for the description of the DW signals of HCC with respect to the statistical model. Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;50:297-304.