基于非高斯分布模型的扩散加权成像在体部疾病中的应用  

The application of non-Gaussion DWI model in body diseases

作　　者：王科[1] 潘婷[1] 周欣[2] 吴光耀[1] 

机构地区：[1]武汉大学中南医院MR室,武汉430071 [2]中国科学院武汉物理与数学研究所,武汉磁共振中心,波谱与原子分子物理国家重点实验室,中国科学院生物磁共振分析重点实验室,湖北430071

出　　处：《磁共振成像》2016年第1期71-76,共6页Chinese Journal of Magnetic Resonance Imaging

基　　金：国家自然科学基金(编号:81171315,81227902)~~

摘　　要：常规扩散加权成像(DWI)在超高b值时,单指数模型不再适用,细胞外间隙水分子的扩散偏离高斯分布,需要更复杂的模型来分析这种非高斯扩散。扩散峰度成像(DKI)能描述水分子的这种非高斯扩散行为,得到额外的参数K_(app),K_(app)不仅能反映组织细胞界面数,还有反映组织细胞微观结构的异质性和不规则性的潜能。近年来DKI在脑外的研究渐多,尤其是在前列腺,研究显示DKI能提高肿瘤检测和准确分级。放射科医师对DKI模型及其参数的准确理解,有助于评估肿瘤环境、肿瘤分型以及治疗反应。作者旨在综述体部非高斯扩散模型DKI的基本原理、生物学相关性、技术要点及在体部中的临床应用。When perform diffusion-weighted imaging（DWI） at ultrahigh b-value, the standard monoexponential model analysis may not be suitable. Water molecules diffusion behaviors in the extracellular space away from Gaussian distribution, thus it is requiring a more sophisticated model for analysis the non-Gaussian behaviors of water. Diffusional kurtosis imaging（DKI） can describe this non-Gaussian diffusion effects of water and provide an additional parameter Kapp, which presumably reflects heterogeneity and irregularity of cellular microstructure, as well as the amount of interfaces within cellular tissue. A few studies have explored DKI outside the brain in rencent years. The most investigated organ is the prostate. Studies have shown that DKI can improve tumor detection and grading. A robust understanding of DKI is necessary for radiologists to better understand the meaning of DKI parameters in the context of different tumors and how these parameters vary between tumor types and in response to treatment. This article reviewed the basic principle, biological correlation,technique highlights and the clinical application in the body of DKI.

关 键 词：非高斯分布 弥散磁共振成像 弥散峰度成像 人体 

分 类 号：R445.2[医药卫生—影像医学与核医学]