Pattern of Reduced Functional Connectivity and Structural Abnormalities in Parkinson's Disease: An Exploratory Study

Author(s):Show less -

Guimaraes, Rachel Paes ; Arci Santos, Maria Cristina ; Dagher, Alain ; Campos, Lidiane Soares ; Azevedo, Paula ; Piovesana, Luiza Gonzaga ; De Campos, Brunno Machado ; Larcher, Kevin ; Zeighami, Yashar ; Scarparo Amato-Filho, Augusto C. ; Cendes, Fernando ; Frota D'Abreu, Anelyssa Cysne

• Document type: Journal article
• Source: FRONTIERS IN NEUROLOGY; v. 7, JAN 13 2017.
• Web of Science Citations: 5

Abstract

Background: MRI brain changes in Parkinson's disease (PD) are controversial. Objectives: We aimed to describe structural and functional changes in PD. Methods: Sixty-six patients with PD (57.94 +/- 10.25 years) diagnosed according to the UK Brain Bank criteria were included. We performed a whole brain analysis using voxel-based morphometry (VBM-SPM 8 software), cortical thickness (CT) using CIVET, and resting-state fMRI using the Neuroimaging Analysis Kit software to compare patients and controls. For VBM and CT we classified subjects into three groups according to disease severity: mild PD {[}Hoehn and Yahr scale (HY) 1-1.5], moderate PD (HY 2-2.5), and severe PD (HY 3-5). Results: We observed gray matter atrophy in the insula and inferior frontal gyrus in the moderate PD and in the insula, frontal gyrus, putamen, cingulated, and paracingulate gyri in the severe groups. In the CT analysis, in mild PD, cortical thinning was restricted to the superior temporal gyrus, gyrus rectus, and olfactory cortex; in the moderate group, the postcentral gyrus, supplementary motor area, and inferior frontal gyrus were also affected; in the severe PD, areas such as the precentral and postentral gyrus, temporal pole, fusiform, and occipital gyrus had reduced cortical thinning. We observed altered connectivity at the default mode, visual, sensorimotor, and cerebellar networks. Conclusion: Subjects with mild symptoms already have cortical involvement; however, further cerebral involvement seems to follow Braak's proposed mechanism. Similar regions are affected both structurally and functionally. We believe the combination of different MRI techniques may be useful in evaluating progressive brain involvement and they may eventually be used as surrogate markers of disease progression. (AU)

• FAPESP's process: 11/19958-4 - Structural and functional conectivity analysis in Parkinsons Disease patients
• Grantee: Rachel Paes Guimarães
• Support type: Scholarships in Brazil - Doctorate
• FAPESP's process: 12/05286-7 - Structural changes using the technique of voxel-based morphometry (VBM) in patients with Parkinson's Disease
• Grantee: Maria Cristina Arci Santos
• Support type: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 13/03358-3 - Resting state functional magnetic resonance imaging in patients with Parkinson Disease and impulsivity
• Grantee: Rachel Paes Guimarães
• Support type: Scholarships abroad - Research Internship - Doctorate