Falangola Maria F, Jensen Jens H, Babb James S, Hu Caixia, Castellanos Francisco X, Di Martino Adriana, Ferris Steven H, Helpern Joseph A
Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, New York 10016, USA.
J Magn Reson Imaging. 2008 Dec;28(6):1345-50. doi: 10.1002/jmri.21604.
To characterize age-related MR diffusion patterns of the prefrontal brain cortex microstructure using a new method for investigating the non-Gaussian behavior of water diffusion called diffusional kurtosis imaging (DKI).
Measures of mean diffusivity (MD), fractional anisotropy (FA) and mean kurtosis (MK) were compared in the prefrontal brain cortex of 24 healthy volunteers (adolescents, young adults, and elderly) ranging from age 13 to 85 years. A Mann-Whitney test was used to compare subject groups with respect to the diffusion measures, and linear regression was used to characterize the change in each diffusion measure as a function of age.
We found significant age-related changes in the elderly adult group, with increase of MD and decrease of FA.
The current study demonstrates distinct mean kurtosis patterns for different age-ranges, with significant age-related correlation for mean kurtosis (MK) and MK peak position, showing that diffusional kurtosis is able to characterize and measure age-related diffusion changes for both grey and white matter, in the developing and aging brain.
使用一种名为扩散峰度成像（DKI）的研究水扩散非高斯行为的新方法，来描述前额叶脑皮质微观结构与年龄相关的磁共振扩散模式。
比较了24名年龄在13至85岁之间的健康志愿者（青少年、年轻人和老年人）前额叶脑皮质的平均扩散率（MD）、各向异性分数（FA）和平均峰度（MK）测量值。采用曼-惠特尼检验比较各受试者组的扩散测量值，并使用线性回归来描述每个扩散测量值随年龄变化的特征。
我们发现老年组存在与年龄相关的显著变化，MD增加而FA降低。
当前研究表明不同年龄范围具有明显不同的平均峰度模式，平均峰度（MK）和MK峰值位置与年龄存在显著相关性，表明扩散峰度能够表征和测量发育中和衰老大脑中灰质和白质与年龄相关的扩散变化。
