Department of Radiology, Division of Emergency and Abdominal Radiology, University of Kentucky, Lexington, KY 40536-0293, USA.
Magn Reson Imaging. 2012 May;30(4):572-8. doi: 10.1016/j.mri.2011.12.013. Epub 2012 Jan 27.
The purpose of this study was to investigate the relationship between liver fat fraction (FF) and diffusion parameters derived from the intravoxel incoherent motion (IVIM) model. Thirty-six subjects with suspected nonalcoholic fatty liver disease underwent diffusion-weighted magnetic resonance imaging with 10 b-values and spoiled gradient recalled echo imaging with six echoes for fat quantification. Correlations were measured between FF, transverse relaxivity (R2), diffusivity (D) and perfusion fraction (f). The primary finding was that no significant correlation was obtained for D vs. FF or f vs. FF. Significant correlations were obtained for D vs. R2 (r=-0.490, P=.002) and f vs. D (r=-0.458, P=.005). The conclusion is that hepatic steatosis does not affect measurement of perfusion or diffusion and therefore is unlikely to confound the use of apparent diffusivity to evaluate hepatic fibrosis.
本研究旨在探讨肝脏脂肪分数（FF）与体素内不相干运动（IVIM）模型衍生的扩散参数之间的关系。36 例疑似非酒精性脂肪性肝病患者接受了扩散加权磁共振成像，共 10 个 b 值和扰相梯度回波成像，共 6 个回波进行脂肪定量。测量了 FF、横向弛豫率（R2）、扩散系数（D）和灌注分数（f）之间的相关性。主要发现是 D 与 FF 或 f 与 FF 之间没有显著相关性。D 与 R2（r=-0.490，P=.002）和 f 与 D（r=-0.458，P=.005）之间存在显著相关性。结论是肝脂肪变性不影响灌注或扩散的测量，因此不太可能混淆应用表观扩散系数评估肝纤维化。
