Functional Covariance Connectivity of Gray and White Matter in Olfactory-Related Brain Regions in Parkinson's Disease.

Yiqing Wang,Yijie Wu,Hongjie Yan,Shouyun Du,Hongyu Wei,Nizhuan Wang,Jianbing Zhu,Xiaojing Li,Yi Wang,Zenglin Cai

doi:10.3389/fnins.2022.853061

Abstract

Before the onset of motor symptoms, Parkinson’s disease (PD) involves dysfunction of the anterior olfactory nucleus and olfactory bulb, causing olfactory disturbance, commonly resulting in hyposmia in the early stages of PD. Accumulating evidence has shown that blood oxygen level dependent (BOLD) signals in white matter are altered by olfactory disorders and related stimuli, and the signal changes in brain white matter pathways show a certain degree of specificity, which can reflect changes of early olfactory dysfunction in Parkinson’s disease. In this study, we apply the functional covariance connectivity (FCC) method to decode FCC of gray and white matter in olfactory-related brain regions in Parkinson’s disease. Our results show that the dorsolateral prefrontal, anterior entorhinal cortex and fronto-orbital cortices in the gray matter have abnormal connectivity with the posterior corona radiata and superior corona radiata in white matter in patients with Parkinson’s hyposmia. The functional covariance connection strength (FCS) of the right dorsolateral prefrontal cortex and white matter, and the covariance connection strength of the left superior corona radiata and gray matter function have potential diagnostic value. These results demonstrate that alterations in FCC of gray and white matter in olfactory-related brain regions can reflect the change of olfactory function in the early stages of Parkinson’s disease, indicating that it could be a potential neuroimaging marker for early diagnosis.

Highlights

Parkinson’s disease (PD) is a progressive neurodegenerative disease that often occurs in middle to old age, and its prevalence gradually increases with aging (Kalia and Lang, 2015; Abeliovich and Gitler, 2016)
Based on logistic analysis of functional covariance connection strength (FCS) values across 19 gray matter voxels, we found that FCS values in the dorsolateral prefrontal cortex of the right cerebral hemisphere were an independent risk factor for PD
Based on logistic analysis of 16 white matter voxel FCS values, we found that the FCS value of the superior corona radiata of the left cerebral hemisphere was an independent risk factor for Parkinson’s disease

Summary

Introduction

Parkinson’s disease (PD) is a progressive neurodegenerative disease that often occurs in middle to old age, and its prevalence gradually increases with aging (Kalia and Lang, 2015; Abeliovich and Gitler, 2016). The reported prevalence of hyposmia in early Parkinson’s disease is up to 90%, making it a potential biomarker of the disease (Xiao et al, 2014), and the hyposmia gradually worsens as the disease progresses after entering the motor-symptom stage (Schapira et al, 2017). It has been accepted as one of the supportive diagnoses of Parkinson’s disease (Postuma et al, 2015) and is considered to be a reliable disease marker (Sui et al, 2019). Further exploration of Parkinson’s disease with hyposmia can help improve the early diagnosis of Parkinson’s disease, so that patients can receive access to treatment earlier and improve quality of life

Methods

Results

Conclusion