QSM as a new powerful tool for clinical practice in neuroimaging

Association between deep gray matter iron deposition and clinical symptoms in Parkinson's disease: a quantitative susceptibility mapping study

Purpose

This study aimed to assess the association between motor and non-motor symptoms of Parkinson's disease (PD) and iron accumulation within the deep gray matter of the brain by Quantitative Susceptibility Mapping (QSM).

Methods

Fifty-six PD patients and twenty-nine healthy controls were recruited in this study. According to the Hoehn and Yahr (H-Y) stage score, PD patients were divided into early stage (H-Y ≤ 2) and advanced stage (H-Y > 2) groups. Specifically, the Regions of Interest (ROIs) encompassed the substantia nigra (SN), red nucleus (RN), caudate nucleus (CN), globus pallidus (GP) and putamen (PT). Meanwhile, various rating scales were used to assess the clinical symptoms of PD.

Results

Compared to healthy controls (HCs), PD patients showed a significant increase in magnetic susceptibility values (MSVs) within the SN and GP. Further comparisons indicated that the MSVs of the SN, PT, GP and CN are all higher in advanced stages than in early stages. Significant positive correlations were observed between the MSVs of the SN and scores on the UPDRS-III, HAMA, and HAMD (r = 0.310, p = 0.020; r = 0.273, p = 0.042; r = 0.342, p = 0.010, respectively). Likewise, the MSVs of the GP demonstrated notable correlations with HAMA and HAMD scores (r = 0.275, p = 0.040; r = 0.415, p = 0.001). Additionally, a significant correlation was found between the MSVs of the PT and HAMD scores (r = 0.360, p = 0.006). Furthermore, we identified a significant negative correlation between MMSE scores and the MSVs of both the PT and GP (r = -0.268, p = 0.046; r = -0.305, p = 0.022).

Conclusion

Our study revealed that QSM possesses the capability to serve as a biomarker for PD. Significant correlations were found between clinical features and the iron deposition in the nigrostriatal system.

Iron Deposition in Parkinson's Disease: A Mini-Review

Iron deposition is crucial pathological changes observed in patients with Parkinson's disease (PD). Recently, scientists have actively explored therapeutic approaches targeting iron deposition in PD. However, several clinical studies have failed to yield consistent results. In this review, we provide an overview of iron deposition in PD, from both basic research and clinical perspectives. PD patients exhibit abnormalities in various iron metabolism-related proteins, leading to disruptions in iron distribution, transport, storage, and circulation, ultimately resulting in iron deposition. Excess iron can induce oxidative stress and iron-related cell death, and exacerbate mitochondrial dysfunction, contributing to the progression of PD pathology. Magnetic resonance imaging studies have indicated that the characteristics of iron deposition in the brains of PD patients vary. Iron deposition correlates with the clinical symptoms of PD, and patients with different disease courses and clinical presentations display distinct patterns of iron deposition. These iron deposition patterns may contribute to PD diagnosis. Iron deposition is a promising target for PD treatment. However, further research is required to elucidate the underlying mechanisms and their impacts on PD.

Evaluating the role of Ginkgo biloba extract in the secondary prevention of acute ischemic stroke with cerebral microbleeds by quantitative susceptibility mapping (QSM)

BACKGROUND

EGb 761, a standardized dry extract of Ginkgo biloba leaves, has certain anti-inflammatory and thrombotic effects and can be used to treat cerebrovascular diseases.

METHODS

A total of 49 patients were randomly assigned to the Aspirin group (24 cases in Controlled group) and the Aspirin + Ginkgo biloba group (25 cases in Treatment group). The quantitative magnetic sensitivity and venous oxygen saturation of cerebral microbleeds were analyzed at admission, discharge, and after follow-up for 3 and 6 months.

RESULTS

The demographic details age, gender, and admission to NIHSS were not significantly different between the two groups (p < 0.05). Quantitative susceptibility mapping (QSM) showed that the magnetic sensitivity of patients in both groups remained stable after 3 and 6 months of follow-up, while the venous oxygen saturation of the Treatment group increased. The venous oxygen saturation at 3 and 6 months of follow-up was negatively correlated with the modified mRS grade score.

CONCLUSIONS

QSM can be used as a quantitative follow-up tool in monitoring both oxygen saturation and Magnetic susceptibility of microbleeds noninvasively in ischemic stroke patients with cerebral microbleeds. EGB combined with Aspirin can improve blood oxygen saturation in those patients and this effect is particularly significant in the long-term efficacy of secondary prevention.