NEFL and Parkinson disease: In addition, the diagnostic accuracy of combining susceptibility values in the CN and NfL levels (AUC: 0.872) was similar with blood NfL levels (AUC: 0.877) with sensitivity 88.9% and specificity 87.2% in separating MSA from PD patients, with a higher accuracy of combining susceptibility values in the DN and blood NfL levels (AUC: 0.843) than susceptibility values in the DN (AUC: 0.697) or blood NfL levels (AUC: 0.764) in differentiating PD from HC.