The QSM values of the substantia nigra were significantly higher in PD patients than in healthy subjects. QSM showed higher diagnostic performance than R2* mapping for the discrimination between PD patients and controls. The QSM value in GPl increases gradually with age, which allows for the identification of GPm in elderly PD subjects. QSM can detect the abnormalities in normal-appearing basal ganglia in patients with neuropsychiatric systemic lupus erythematosus (NPSLE), which likely represents increased iron deposition.