Bing Zhang PhD, Presenter: Nothing to Disclose

Ming Li, Abstract Co-Author: Nothing to Disclose

Xin Zhang MD, MS, Abstract Co-Author: Nothing to Disclose

Fei Chen MS, Abstract Co-Author: Nothing to Disclose

Huiting Wang MS, Abstract Co-Author: Nothing to Disclose

Fang Zhang, Abstract Co-Author: Nothing to Disclose

Jiange Zhang, Abstract Co-Author: Nothing to Disclose

yun xu, Abstract Co-Author: Nothing to Disclose

Bin Zhu, Abstract Co-Author: Nothing to Disclose

To investigate alteration pattern of gray matter and small-world networks in the human brain revealed by quantitative water diffusivity from MRI for aMCI and AD.

In total, 30 patients with AD, 30 patients with aMCI, and 30 normal controls (NCs) were recruited. DWI was performed at 3.0 T with FLAIR, and the independent ADC mapping was generated using DTIStudio software. Ninety automated anatomic labeling atlas (AAL) for regional parcellations were adopted in software Brain Search (BS), which is developed by our group. The gray scale intensities (namely ADC value for water diffusivity) of each anatomical brain region were compared among aMCI, AD and NC by BS. In order to explore the network in patients’ brain, the statistical similarity in ADC value between each AAL was measured by the Pearson correlation coefficient across subjects and interregional correlation matrix. In addition, a graph theoretical analysis was performed by Brainnetviewer software to explore the small world properties.

During the pathological process of AD, the changes of water diffusivity appeared first in the left hippocampus, then gradually progressed to the bilateral sides and eventually displayed right lateralization. The ADC values from aMCI were obviously elevated compared to the values from the NC group in the left limbic cortex. There was a negative correlation between the ADC values and the scores from MMSE, MoCA, the Digit test, Raven's IQ, and WAIS IQ. Additionally, the ADC values were positively correlated with the scores from CDR, ADL, and ADAS-Cog. The number of the correlation matrix is reduced in patients with aMCI and AD, while r>0.8. Global and local efficiency as well as these coefficients are in consistent with the small world network property with lower cost (<0.5) and higher efficiency (>0.5) and global efficiency decreased in aMCI and AD. The mean degree of human brain diffusivity networks decreased in aMCI and AD.

The water diffusivity for aMCI and AD displays asymmetric anatomical lateralization. Left HP connectivity dismissed in aMCI firstly, while r>0.6. Connectivity Degree in the right HP is larger than the left. The global efficiency and the connectivity degree decreasing reflected a more regular configuration in aMCI and AD brain networks.

Quantitative water diffusivity MRI can demonstrate alteration pattern of gray matter and small-world networks in the brain.

Zhang, B, Li, M, Zhang, X, Chen, F, Wang, H, Zhang, F, Zhang, J, xu, y, Zhu, B, Alteration Pattern of Gray Matter and Small-World Networks in the Human Brain Revealed by Quantitative Water Diffusivity from MRI.  Radiological Society of North America 2012 Scientific Assembly and Annual Meeting, November 25 - November 30, 2012 ,Chicago IL. http://archive.rsna.org/2012/12022866.html