Iron metabolism and its detection through MRI in parkinsonian disorders: a systematic review

Iron deposition in the brain normally increase with age, but its accumulation in certain regions is ob- served in a number of neurodegenerative diseases in- cluding Parkinson’s disease (PD) and other parkinson- isms. Whether iron overload leads to dopaminergic neu- ronal death in the SN of PD patients or is instead sim- ply a by-product of the neurodegenerative progression is still yet to be ascertained. Magnetic resonance imaging (MRI) is a non-invasive method to assess brain iron content in PD patients. In PD, accurate radiologic visu- alization of basal ganglia is required. Deep gray matter nuclei are well presented in T2- and T2*-weighted im- ages. T2*-weighted gradient-echo (GRE) is widely used to assess calcifications and also for iron detection. On the other hand, new methods specifically designed for detecting iron-induced susceptibility differences can be further improved by sequences like susceptibility- weighted imaging (SWI). In the present review, we aim to summarize the available data on brain iron de- position in PD.