Quantitative susceptibility mapping in atypical Parkinsonisms

Abstract

Background and purposeDifferential diagnosis between Parkinson's disease (PD) and Atypical Parkinsonisms, mainly Progressive Supranuclear Palsy (PSP) and Multiple System Atrophy (MSA), remains challenging. The low sensitivity of macroscopic findings at imaging might limit early diagnosis. The availability of iron-sensitive MR techniques and high magnetic field MR scanners provides new insights in evaluating brain structures in degenerative parkinsonisms. Quantitative Susceptibility Mapping (QSM) allows quantifying tissue iron content and could be sensitive to microstructural abnormalities which precede the appearence of regional atrophy. We measured the magnetic susceptibility (χ) of nigral and extranigral regions in patients with PD, PSP and MSA to evaluate the potential utility of the QSM technique for differential diagnosis.Materials and methods65 patients (36 PD, 14 MSA, 15 PSP) underwent clinical and radiological evaluation with 3 T MRI. QSM maps were obtained from GRE sequences. ROI were drawn on substantia nigra (SN), red nucleus (RN), subthalamic nucleus (STN), putamen, globus pallidus and caudate. χ values were compared to detect inter-group differences.ResultsThe highest diagnostic accuracy for PSP (area under the ROC curve, AUC, range 0.9–0.7) was observed for increased χ values in RN, STN and medial part of SN whereas in MSA (AUC range 0.8–0.7) iron deposition was significantly higher in the putamen, according to the patterns of pathological involvement that characterize the different diseases.ConclusionQSM could be used for iron quantification of nigral and extranigral structures in all degenerative parkinsonisms and should be tested longitudinally in order to identify early microscopical changes.

MRI-Based Radiomics of Basal Nuclei in Differentiating Idiopathic Parkinson’s Disease From Parkinsonian Variants of Multiple System Atrophy: A Susceptibility-Weighted Imaging Study

“…However, the RN and GP were not capable of differentiating between MSA from IPD patients in our study. Furthermore, the CN has been reported to be have no statistical differences in iron content between PD and AP patients (Han et al, 2013;Sjostrom et al, 2017;Mazzucchi et al, 2019). Similarly, in our present study, the radiomic features extracted from the RN, GP, and CN showed moderate to poor differential diagnostic values.…”

“…Similarly, in our present study, the radiomic features extracted from the RN, GP, and CN showed moderate to poor differential diagnostic values. However, Mazzucchi et al (2019) found that the STN might be useful for differentiating MSA from PD. This discrepancy may be due to the small size of the STN and difficulty in its visualization on SWI.…”

“…Pathological studies have demonstrated that abnormal iron levels in a series of nigral and extranigral regions should be considered as candidate biomarkers to differentiate IPD from AP and controls, including the PUT, CN, GP, RN, subthalamic nuclei (STN), and substantia nigra (SN). On the basis of these studies, the selection of regions of interest (ROIs) was confirmed (Dickson, 2012;Mazzucchi et al, 2019). Considering that iron distribution is heterogenous, ROIs were drawn on the continuous layers to obtain volumes of interest (VOIs).…”

Modern Brainstem MRI Techniques for the Diagnosis of Parkinson's Disease and Parkinsonisms

“…Concerning the differential diagnosis between PD and atypical parkinsonism's, QSM techniques allow for more sensitive measures in the nigral and extranigral regions. Mazzucchi et al (32) found that the greatest diagnostic accuracy for PSP was for increased χ values in the RN, subthalamic nucleus (STN), and medial part of the SN, whereas for MSA, it was a significantly higher level of iron deposition in the putamen, reflecting the different patterns of pathological involvement that characterize these diseases (32).…”

SEPIA - SuscEptibility mapping PIpeline tool for phAse images

“…Unlike in conventional T1-weighted and T2*-weighted imaging, these two types of substances generate opposite image contrasts in QSM, making it particularly useful in applications where the tissues with opposite properties need to be distinguished, such as between haemorrhages and calcifications (Chen et al, 2013). Additionally, strong correlations were demonstrated in various ex vivo studies between iron concentration in the deep nuclei and magnetic susceptibility (Langkammer et al, 2012;Sun et al, 2015), showing evidence of the quantitative ability of QSM which can find applications on studying, for example, the relationships between iron overload and neurodegenerative diseases, including Parkinson's disease (He et al, 2015;Ide et al, 2015;Langkammer et al, 2016;Mazzucchi et al, 2019;Thomas et al, 2020), Huntington's disease (Chen et al, 2018;, Alzheimer's disease (Acosta-Cabronero et al, 2013;Bulk et al, 2020;Du et al, 2018;Gong et al, 2019;O'Callaghan et al, 2017), and between iron deposition in the brain and ageing (Acosta-Cabronero et al, 2016;Betts et al, 2016;Bilgic et al, 2012;Gong et al, 2015;Keuken et al, 2017;Liu et al, 2016;Persson et al, 2015).…”