Christian Langkammer1,2, Nikolaus Krebs2, Walter Goessler3, Eva Scheurer2, Michaela Soellinger1, Kathrin Yen2, Franz Fazekas1, Stefan Ropele1
1Department of Neurology, Medical University of Graz, Graz, Austria; 2Ludwig Boltzmann Institute for Clinical-Forensic Imaging, Graz, Austria; 3Institute of Chemistry - Analytical Chemistry, University of Graz, Graz, Austria
This study investigated possible contributions of iron deposition, myelin density and fiber orientation on R2* relaxation rates in white matter by using quantitative MRI of postmortem brains in situ and by assessing regional iron concentrations with inductively coupled plasma mass spectrometry. The results suggest that the density of myelin is the dominant determinant of R2* in white matter while the presence of iron additionally has a strong effect. Our results do not support the hypothesis that fiber orientation contributes to the phenomenon of T2* relaxation.