Motivation: Quantification of iron overload in relevant brain regions is crucial for Parkinson&amp;rsquo;s disease (PD) diagnosis and monitoring.Goal(s): To evaluate and compare manual and automated approaches for substantia nigra (SN) and nigrosome1 (N1) identification and iron content assessment using quantitative susceptibility mapping (QSM)Approach: Histogram analysis to assess distributions of iron content in SN and N1, and compare them in patients with PD and controlsResults: Histogram analysis of automatically defined SN regions of interest in PD can be a promising tool to complement current diagnostic procedures. Nigrosome1 identification is confirmed to be more challengeing, and should be carefully checked by expert raters.Impact: Lean and accurate quantification of iron overload in Substantia Nigra and Nigrosome1 in parkinsonian patients could represent an added value to routine clinical evaluation, enhancing accuracy of early diagnosis, possibly in pre-morbid conditions, as well as optimal treatment monitoring

Substantia Nigra and Nigrosome1 identification in Parkinson’s disease and healthy controls: comparison of manual and automated approach at 3T