DataSheet_1_Statistical Evaluation of Different Mathematical Models for Diffusion Weighted Imaging of Prostate Cancer Xenografts in Mice.pdf

PurposeTo evaluate fitting quality and repeatability of four mathematical models for diffusion weighted imaging (DWI) during tumor progression in mouse xenograft model of prostate cancer.MethodsHuman prostate cancer cells (PC-3) were implanted subcutaneously in right hind limbs of 11 immunodeficient mice. Tumor growth was followed by weekly DWI examinations using a 7T MR scanner. Additional DWI examination was performed after repositioning following the fourth DWI examination to evaluate short term repeatability. DWI was performed using 15 and 12 b-values in the ranges of 0-500 and 0-2000 s/mm2, respectively. Corrected Akaike information criteria and F-ratio were used to evaluate fitting quality of each model (mono-exponential, stretched exponential, kurtosis, and bi-exponential).ResultsSignificant changes were observed in DWI data during the tumor growth, indicated by ADCm, ADCs, and ADCk. Similar results were obtained using low as well as high b-values. No marked changes in model preference were present between the weeks 1−4. The parameters of the mono-exponential, stretched exponential, and kurtosis models had smaller confidence interval and coefficient of repeatability values than the parameters of the bi-exponential model.ConclusionStretched exponential and kurtosis models showed better fit to DWI data than the mono-exponential model and presented with good repeatability.

目的：本实验旨在评估四种数学模型（单指数模型、拉伸指数模型、峰度模型和双指数模型）在鼠前列腺癌异种移植模型肿瘤进展过程中对扩散加权成像（DWI）拟合质量及可重复性的适用性。方法：将人前列腺癌细胞（PC-3）植入11只免疫缺陷小鼠右侧后肢皮下。通过每周使用7T磁共振扫描器进行DWI检查来监测肿瘤生长。在第四次DWI检查后，进行额外的DWI检查以评估短期可重复性。使用15和12 b值，分别在0-500 s/mm²和0-2000 s/mm²的范围内进行DWI。通过校正的赤池信息准则和F值来评估每个模型的拟合质量。结果：在肿瘤生长过程中，DWI数据表现出显著变化，这体现在ADCm、ADCs和ADCk上。使用低b值和高b值均得到相似的结果。在1-4周期间，模型偏好并未出现明显变化。单指数模型、拉伸指数模型和峰度模型的参数置信区间和可重复性系数值均小于双指数模型的参数。结论：拉伸指数模型和峰度模型相较于单指数模型，更符合DWI数据，并展现出良好的可重复性。