Abstract #2438

Diffusion Tensor Imaging Enhanced Anisotropic MRE of the Brain

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.