基于脑微结构信息检测的扩散峭度成像多b值组合优化  

Optimum b-Value Acquisition Schemes of Diffusion Kurtosis Imaging Based on Brain Microstructural Information Detection

作　　者：沙淼[1] 陈元园[1] 倪红艳[2] 王伟伟[1] 赵欣[1] 

机构地区：[1]天津大学精密仪器与光电子工程学院,天津300072 [2]天津市第一中心医院放射科,天津300192

出　　处：《纳米技术与精密工程》2015年第6期414-419,共6页Nanotechnology and Precision Engineering

基　　金：国家自然科学基金资助项目(81222021;31271062;61172008;81171423;51007063);国家科技支撑计划资助项目(2012BAI34B02);教育部新世纪优秀人才支持计划资助项目(NCET-10-0618);天津市自然科学基金青年基金资助项目(13JCQNJC14400)

摘　　要：扩散峭度成像(DKI)引入高阶峭度张量来量化水分子扩散的非高斯程度,并可采用多种扩散敏感因子b值参与模型拟合,能反映组织复杂结构更微小变化,因而在脑神经科学研究与临床诊断中具有独特优势.但目前尚缺乏不同b值组合DKI数据采集对不同脑微结构特征的比较分析和针对不同临床需求制定DKI数据采集的最优b值组合方案的思路.本文从脑脊液、灰质和白质的DKI图像对比度角度,结合基于体素统计分析方法比较了5个不同b值组合与高、低2个b值组合采集方案对DKI成像指标的影响及在胼胝体局部组织微结构特征表达的差异.结果表明,低b值(<1 000 s/mm^2)和高b值(>2 000 s/mm^2)采集成像皆有较强的组织分辨能力,而过多增加b值组合个数会增大拟合误差并增加采集时间;使用高、低2个b值(2 000 s/mm^2与1 000 s/mm^2)的组合采集方案较适合于一般DKI临床诊断.Diffusion kurtosis imaging （ DKI ） , introducing a higher-order kurtosis tensor to quantify the non-Gaussian property of water diffusion as well as multiple diffusion weighted factor b-values to model fit-ting, is a powerful probe for assessment of the microstructure of biological tissues, enjoying a unique ad-vantage in neuroscience and clinic diagnosis.However, there is still a lack of comparative analysis on different features of microstructure of brain using different b-value combinations in DKI data acquisition and thoughts of optimizing b-value combinations of DKI data acquisition according to different clinical needs.In this paper, DKI image contrast of cerebrospinal fluid, gray matter and white matter and voxel-based analysis of the whole brain were used to compare the influence of DKI parameter under 5 b-values scheme and 2 b-values scheme and the differences of corpus callosum local tissue microstructure charac-teristic expression.Results show that the combination of low b-value （〉1 000 s/mm^2 ） and high b-value （〈2 000 s/mm^2 ） DKI scheme has great resolution ability for tissues, while more b-values collected at＆amp;nbsp;the same time increase the acquisition time and the model fitting error as well;2 b-values scheme （ 1 000 s/mm^2 , 2 000 s/mm^2 ） will be more suitable for general DKI clinical diagnosis.

关 键 词：扩散峭度成像 扩散敏感因子b值 组织微结构 

分 类 号：R338[医药卫生—人体生理学]