MAGNETIC-RESONANCE-IMAGING OF BRAIN IRON IN HEALTH AND DISEASE

Brain iron is a major contributor to magnetic resonance imaging (MRI) contrast in normal gray matter, and its role in the pathogenesis of di fferent neurological disorders has also become apparent. Non-heme brai n iron is present in the brain mainly in the form of ferritin, The uni que magnetic properties of ferritin determine different signal changes on both T1- and T2 weighted images, and the T2 relaxation rates have a linear dependence on applied field strength, This finding is typical for ferric oxyhydroxide cores. The resulting T2-shortening also depen ds on echo-spacing used in the imaging sequence as well as on the wate r diffusion coefficient and the size of the ferritin cluster, Quantita tion of non-heme brain iron by MRI aids in the diagnosis and monitorin g of different neurological diseases.