Alterations in the limbic/paralimbic cortices of Parkinson's disease patients with hyposmia under resting-state functional MRI by regional homogeneity and functional connectivity analysis. Issue 7 (July 2015)

• Record Type: Journal Article
• Authors: Su, Meilan; Wang, Song; Fang, Weidong; Zhu, Yingcheng; Li, Rong; Sheng, Ke; Zou, Dezhi; Han, Yu; Wang, Xuefeng; Cheng, Oumei
• Is Part Of: Parkinsonism & related disorders. Volume 21:Issue 7(2015)
• Page Start: 698
• Page End: 703
• Publication Date: 2015-07
• Subjects: Parkinson's disease -- Periodicals; Movement disorders -- Periodicals; Movement Disorders -- Periodicals; Nerve Degeneration -- Periodicals; Nervous System Diseases -- Periodicals; Parkinson Disease -- Periodicals; Tremor -- Periodicals; Parkinson, Maladie de -- Périodiques; Parkinson's disease; 616.833
• DOI: 10.1016/j.parkreldis.2015.04.006
• Languages: English
• ISSNs: 1353-8020

Abstract

<abstract xml:lang="en" abstract-type="author" id="abs0010"> <title id="sectitle0010">Abstract</title> <sec> <title id="sectitle0015">Background</title> <p id="abspara0010">Hyposmia is a cardinal early symptom of Parkinson's disease (PD), but the pathophysiological mechanisms underlying it remain unclear. Resting-state functional MRI (RS-fMRI) demonstrates spontaneous neuronal activity. We hypothesized that there would be alterations in the olfaction-related regions of the limbic/paralimbic cortices in PD patients with obvious hyposmia by RS-fMRI.</p> </sec> <sec> <title id="sectitle0020">Methods</title> <p id="abspara0015">We used the "Five Odors for Olfactory Detection Arrays" to test the threshold of olfactory detection (TOD) for 54 PD patients and 22 age-matched controls. Using the mean TOD of the control group, patients were subdivided into two groups: PD with obvious hyposmia (OH-PD, n = 38) and PD with none/less obvious hyposmia (NOH-PD, n = 16). The regional brain activity of all subjects was investigated using RS-fMRI, in combination with regional homogeneity (ReHo) and functional connectivity (FC) analysis.</p> </sec> <sec> <title id="sectitle0025">Results</title> <p id="abspara0020">There were different ReHo values in the limbic/paralimbic cortices between the OH-PD and NOH-PD groups. ReHo was significantly decreased in OH-PD patients in parts of the traditional olfactory regions (e.g. the amygdala, olfactory gyrus, orbital frontal cortex, parahippocampal gyrus and insula) and some non-traditional olfactory centers (e.g. the rectal gyrus and superior temporal pole), while increased in the left anterior/posterior cingulate cortex. FC analysis revealed decreased functional connectivity within the limbic/paralimbic cortices, especially in regions with reduced ReHo in the OH-PD group.</p> </sec> <sec> <title id="sectitle0030">Conclusions</title> <p id="abspara0025">PD with hyposmia is related to altered functional activity not only in the traditional olfactory center, but also in some non-traditional olfactory regions of the limbic/paralimbic cortices.</p> </sec> </abstract>