Jongho Lee1,2, Peter van Gelderen1, Li-Wei Kuo1, Hellmut Merkle1, Afonso C. Silva3, Jeff H. Duyn1
1Advanced MRI section/LFMI/NINDS, National Institutes of Health, Bethesda, MD, United States; 2Department of Radiology, University of Pennsylvania , Philadelphia, PA, United States; 3CMU/LFMI/NINDS, National Institutes of Health, Bethesda, MD, United States
The dependence of T2* on fiber orientation relative to B0 was studied in post-mortem human brain tissue. We found an orientation dependence with sin2θ and sin4θ components. This dependence could be accurately explained by a model of microscopic susceptibility variations together with significant susceptibility anisotropy. Based on this, we constructed a T2* orientation map that closely resembled a fiber orientation map derived from DTI.