Theoretical model and experimental evaluation of cellular, BOLD and nonheme Iron contributions to the quantitative Gradient Recalled Echo (qGRE) and quantitative susceptibility mapping (QSM) signals in basal ganglia.

Nonheme iron is an important element supporting the structure and functioning of biological tissues. Misbalance in nonheme iron can lead to different neurological disorders. Several MRI approaches have been developed for iron quantification relying either on the relaxation or susceptibility features of MRI signal. Specific quantification of the nonheme iron can, however, be tempered by the heme iron in the deoxygenated blood. The goal of this presentation is to introduce theoretical background and experimental method allowing disentangling contributions of heme and nonheme irons simultaneously with evaluation of tissue neuronal density in the basal ganglia.