OBJECTIVE The motor dysfunctions always affect hemi-body first in Parkinson's disease (PD). However, the interhemispheric relationships in patients with only unilateral motor impairment were barely known to date. We aimed to investigate the interhemispheric functions using resting-state functional Magnetic resonance imaging (RS-fMRI) for further understanding the pathogenesis of PD. METHODS Forty-three unilateral-symptomatic PD patients (UPD, Hoehn-Yahr staging scale, H-Y: 1-1.5), and 54 age-, gender-, education-matched normal controls (NC) were recruited. All subjects underwent MRI scanning and clinical evaluations. The interhemispheric coordination (Voxel-Mirrored Homotopic Connectivity, VMHC) and hemispheric dominance pattern (laterality index of eigenvector centrality mapping, LI-ECM) were calculated. Afterwards, correlation analyses and receiver operating characteristic (ROC) curve analysis were employed. RESULTS Compared with NC, UPD group showed significantly decreased VMHC in bilateral sensorimotor regions which was negatively correlated with the motor score. Furthermore, at the cut-off homotopic connectivity of 0.604, statistically significant ability of VMHC to discriminate UPD from NC with area under ROC curve (AUC) = 0.759, p < 0.001; specificity = 74.4%; sensitivity = 68.5% was observed. No difference was detected in UPD patients as for ECM and LI-ECM. CONCLUSIONS The disrupted interhemispheric coordination in bilateral sensorimotor regions may have significant implications for elucidating the mechanisms underlying the hemiparkinsonism and enabling the uncovering of complex mechanisms of PD.

中文翻译：

---

中断的半球间协调与未受影响的全球特征向量中心性的单侧化是偏帕金森症的特征。

目的运动功能障碍总是首先影响帕金森病（PD）的半身。然而，迄今为止，几乎不知道仅有单侧运动障碍的患者的半球间关系。我们旨在使用静息态功能磁共振成像 (RS-fMRI) 研究半球间功能，以进一步了解 PD 的发病机制。方法 招募了 43 名单侧有症状的 PD 患者（UPD，Hoehn-Yahr 分期量表，HY：1-1.5）和 54 名年龄、性别、教育匹配的正常对照（NC）。所有受试者均接受 MRI 扫描和临床评估。计算了半球间协调（Voxel-Mirrored Homotopic Connectivity，VMHC）和半球优势模式（特征向量中心映射的侧向指数，LI-ECM）。然后，采用相关分析和受试者工作特征（ROC）曲线分析。结果与NC相比，UPD组双侧感觉运动区VMHC显着降低，与运动评分呈负相关。此外，在 0.604 的截止同伦连接性，VMHC 区分 UPD 和 NC 的统计显着能力，ROC 曲线下面积 (AUC) = 0.759，p < 0.001；特异性 = 74.4%；观察到灵敏度 = 68.5%。在 UPD 患者中未检测到 ECM 和 LI-ECM 的差异。结论双侧感觉运动区域的半球间协调中断可能对阐明偏帕金森症的潜在机制和揭示 PD 的复杂机制具有重要意义。