Department of Radiology, Boston University Medical Center, Boston, MA 02218, USA.
Magn Reson Imaging. 2012 Dec;30(10):1475-82. doi: 10.1016/j.mri.2012.05.010. Epub 2012 Aug 22.
The purpose of this study was to evaluate the non-Gaussian behavior of diffusion related signal decay of the ex vivo murine liver tissues from a dietary model of hepatic fibrosis. To this end, a biexponential formalism was used to model high b-value diffusion imaging (up to 3500 s/mm(2)), the findings of which were correlated with liver histopathology and compared to a simple monoexponential model. The presence of a major, fast diffusing component and a minor, slow diffusing component was demonstrated. With increasing hepatic fibrosis, the fractional contribution of the fast diffusing component decreased, as did the diffusion coefficient of the fast diffusing component. Strong correlation between the degrees of liver fibrosis and a two-predictor regression model incorporating parameters of the biexponential model was found. Using Akaike's Information Criterion analyses, the biexponential model resulted in an improved fit of the high b-value diffusion data when compared to the monoexponential model.
本研究旨在评估膳食诱导肝纤维化模型中离体鼠肝组织弥散相关信号衰减的非高斯行为。为此，采用双指数公式对高 b 值弥散成像（最高达 3500 s/mm²）进行建模，将所得结果与肝组织病理学进行相关分析，并与简单的单指数模型进行比较。结果显示存在一个主要的快速弥散成分和一个次要的缓慢弥散成分。随着肝纤维化程度的增加，快速弥散成分的分数贡献减少，快速弥散成分的扩散系数也降低。发现肝纤维化程度与包含双指数模型参数的双预测因子回归模型之间具有很强的相关性。通过赤池信息量准则分析，与单指数模型相比，双指数模型对高 b 值弥散数据的拟合更好。
