内容紹介
近年、Diffusion tensor imaging(DTI)より新たな拡散MRI解析手法が数多く提案され、その有用性が報告されている。水分子拡散の正規分布モデルを仮定するDTIでは、実際の複雑な生体組織構造を完全に推定するには限界がある。そのため、DTIの限界を乗り越えるべく、diffusional kurtosis imaging(DKI)、Neurite Orientation Dispersion and Density Imaging(NODDI)など新たな拡散MRIの解析法が提案されている。これらの技術は認知症研究へも応用され、その有用性が報告されている。本稿ではDKI、NODDIの簡単な理論背景と認知症研究への応用について概説する。
Diffusion MRI makes it possible to evaluate the microstructure of nerve tissue, which is much smaller than the resolution of MRI, by estimating the micron-scale displacement of water molecules diffusing within the tissue. In recent years, new diffusion MRI analysis techniques such as diffusional kurtosis imaging (DKI) and neurite orientation dispersion and density imaging (NODDI) have been proposed. These techniques enable the evaluation of the structure and function of the nervous system in more detail. This review outlines the application of these new diffusion MRI techniques to the recent neuroimaging study of dementia.
目次
Diffusion MRI makes it possible to evaluate the microstructure of nerve tissue, which is much smaller than the resolution of MRI, by estimating the micron-scale displacement of water molecules diffusing within the tissue. In recent years, new diffusion MRI analysis techniques such as diffusional kurtosis imaging (DKI) and neurite orientation dispersion and density imaging (NODDI) have been proposed. These techniques enable the evaluation of the structure and function of the nervous system in more detail. This review outlines the application of these new diffusion MRI techniques to the recent neuroimaging study of dementia.