Guangqiang Geng1, Michael Green1, Caroline Rae1, 2, Ralph Sinkus3, Roland G. Henry4, Lynne E. Bilston1, 5
1Neuroscience Research Australia, Sydney, NSW, Australia; 2UNSW, Sydney, NSW, Australia; 3Centre de Recherches Biomdicales Bichat-Beaujon, Paris, France; 4Departments of Radiology and Biomedical Imaging, Neurology, and Bioengineering Graduate Group, University of California, San Francisco, CA, United States; 5Prince of Wales Clinical School, UNSW, Sydney, NSW, Australia
Magnetic Resonance Elastography (MRE) measures the mechanical properties of the brain in vivo. Most brain MRE studies have assumed isotropy regardless to the anisotropy shown by diffusion tensor imaging (DTI). We combine MRE and DTI to investigate the anisotropic viscoelasticity of human brains. In WM, shear modulus (┴=2.440.05kPa) and its anisotropy (FA=0.320.01) were significantly greater (ANOVA, p=0.0107 and 0.0011) than in GM (┴= 2.020.07kPa, FA=0.240.00), consistent with rheological measurements. Also, μFA increased significantly (p<0.0001) from 0.27 to 0.35 when DTI FA increased from 0.26 to 0.54. DTI enhanced MRE enabled a reliable mapping for the anisotropic viscoelasticity of human brains.