Session Information
Date: Wednesday, September 25, 2019
Session Title: Neuroimaging
Session Time: 1:15pm-2:45pm
Location: Les Muses Terrace, Level 3
Objective: To investigate the integrity of cerebellothalamocortical circuit (CTCC) and basal ganglia-cortical loop (BGCL) connectivity in tremor-dominant PD (TD-PD) and compare with a group of akinetic-rigid PD (AR-PD) and healthy controls (HCs).
Background: The CTCC and the BGCL have been suggested as key modulatory networks of motor control. Impairment within CTCC and BGCL may underlie the development of tremor in patients with Parkinson’s disease (PD)
Method: We used 3-Tesla MRI with diffusion tensor imaging (DTI) and resting state functional MRI (fMRI) and generated pilot data out of 12 PD patients [6 TD-PD (age: 51.4±8.7yrs; disease duration: 4.4±2.2yrs) and 6 AR-PD (age: 52.4±10.8yrs; disease duration: 4.4±2.6yrs)] and 6 HCs (age:54.5±7.33yrs). CTCC and BGCL network maps were developed through atlases and corrected manually. Analyses included strength of functional connectivity, mean diffusivity (MD), and fractional anisotropy (FA) in cerebellum, striatum, globus pallidus (GP), subthalamic nucleus (STN), primary and premotor thalamus, substantia nigra, red nucleus (RN), dentate nucleus, pre-central gyrus, supramarginal gyrus, posterior parietal lobule and secondary motor are
Results: In TD-PD compared to HCs, functional connectivity was (a) reduced between the internal GP and RN (P=0.0059) and STN (P=0.023); (b) reduced between the STN and premotor thalamus (P=0.038); (c) reduced between the caudate and supramarginal gyrus (P=0.0054); and (d) increased between the cerebellar cortex and STN (P=0.030). In TD-PD compared to AR-PD, functional connectivity was (a) reduced between the STN and premotor thalamus (P=0.048); and (b) reduced between the caudate and supramarginal gyrus (P=0.0414). TD-PD subjects showed reduced FA in dentate nucleus ompared to AR-PD (P=0.031).
Conclusion: These are pilot data demonstrating preliminary evidence of altered functional connectivity between regions that constitute the CTCC and BGCL networks in patients with TD-PD. We anticipate the analyses of the full cohort to generate more robust conclusions for the specific alterations within CTCC/ BGCL that may underlie the pathophysiology of tremor in PD.
To cite this abstract in AMA style:
Z. Chappell, H. Wilson, M. Politis. Motor Networks in Tremor-Dominant Parkinson’s Disease. A resting-state functional MRI and diffusion tensor imaging analysis. [abstract]. Mov Disord. 2019; 34 (suppl 2). https://www.mdsabstracts.org/abstract/motor-networks-in-tremor-dominant-parkinsons-disease-a-resting-state-functional-mri-and-diffusion-tensor-imaging-analysis/. Accessed June 14, 2025.« Back to 2019 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/motor-networks-in-tremor-dominant-parkinsons-disease-a-resting-state-functional-mri-and-diffusion-tensor-imaging-analysis/