Quantitative Susceptibility Mapping and Free Water Imaging of Substantia Nigra in Parkinson’s Disease

Article type: Research Article

Authors: Zhang, Dongling^{a; c; 1} | Yao, Junye^{b; 1} | Sun, Junyan^{a; c} | Tong, Qiqi^e | Zhu, Silei^f | Wang, Junling^{a; c} | Chen, Lili^{a; c} | Ma, Jinghong^g | He, Hongjian^{b; h; *} | Wu, Tao^{a; c; d; *}

Affiliations: [a] Center for Movement Disorders, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China | [b] Center for Brain Imaging Science and Technology, College of Biomedical Engineering and Instrument Science, Zhejiang University, Hangzhou, Zhejiang, China | [c] China National Clinical Research Center for Neurological Diseases, Beijing, China | [d] Parkinson’s Disease Center, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China | [e] Research Center for Healthcare Data Science, Zhejiang Lab, Hangzhou, Zhejiang, China | [f] Wellcome Centre for Integrative Neuroimaging, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom | [g] Department of Neurobiology, Xuanwu Hospital of Capital Medical University, Beijing Institute of Geriatrics, Beijing, China | [h] School of Physics, Zhejiang University, Hangzhou, Zhejiang, China

Correspondence: [*] Correspondence to: Tao Wu, Center for Movement Disorders, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, 100070, Beijing, China. Tel.: +86 10 83198271; Fax: +86 10 83161294; E-mail: wutao69@163.com; Hongjian He, College of Biomedical Engineering and Instrument Science, Zhejiang University, Hangzhou, China. Tel.: +0571 86971875; Fax: +0571 86971875; E-mail: hhezju@zju.edu.cn.

Note: [1] These authors contributed equally to this work.

Abstract: Background:The utility of imaging methods to detect iron content in the substantia nigra pars compacta (SNc) and free water imaging in the posterior substantia nigra (pSN) has the potential to be imaging markers for the detection of Parkinson’s disease (PD). Objective:This study aimed to compare the discriminative power of above methods, and whether the combination can improve the diagnostic potential of PD. Methods:Quantitative susceptibility mapping (QSM) and diffusion-weighted data were obtained from 41 healthy controls (HC), 37 patients with idiopathic REM sleep behavior disorder (RBD), and 65 patients with PD. Mean QSM values of bilateral SNc and mean isotropic volume fraction (Viso) values of bilateral pSN (mean QSM|Viso values of bilateral SNc|pSN) were separately calculated and compared among the groups. Results:Mean QSM|Viso values of bilateral SNc|pSN were significantly higher for RBD and PD patients compared to HC and were significantly higher in PD patients than in RBD patients. The power of the mean QSM|Viso values of bilateral SNc|pSN and combined mean QSM and Viso values was 0.873, 0.870, and 0.961 in discriminating PD and HC, 0.779, 0.719, and 0.864 in discriminating RBD from HC, 0.634, 0.636, and 0.689 in discriminating PD and RBD patients. Conclusion:QSM and free water imaging have similar discriminative power in the detection of prodromal and clinical PD, while combination of these two methods increases discriminative power. Our findings suggest that the combination of QSM and free water imaging has the potential to become an imaging marker for the diagnosis of PD.

Keywords: Iron accumulation, free water, quantitative susceptibility mapping, isotropic volume fraction, Parkinson’s disease

DOI: 10.3233/JPD-223499

Journal: Journal of Parkinson's Disease, vol. 12, no. 8, pp. 2469-2478, 2022