Subcortical microstructural diffusion changes correlate with gait impairment in Parkinson's disease.

Area of Science:

• Neuroimaging
• Neurology
• Biomedical Engineering

Background:

• Gait impairments are a hallmark of Parkinson's Disease (PD), stemming from degeneration in crucial brain circuits.
• Diffusion tensor imaging (DTI) measures microstructural integrity (FA/MD) in brain tissues.
• Previous research suggests a link between brain circuit degeneration and motor deficits in PD.

Purpose of the Study:

• To investigate microstructural alterations in brain locomotion control centers in PD using DTI.
• To correlate DTI-derived measures with clinical and quantitative gait parameters in PD patients.

Main Methods:

• Recruited 21 PD patients with gait impairment and 15 controls.
• Conducted quantitative gait and clinical assessments in PD patients (medication ON/OFF).
• Performed Region of Interest (ROI) analysis on thalamus, basal ganglia, and mesencephalic locomotion centers (MLC) using DTI, examining FA and MD.

Main Results:

• Observed significant microstructural differences in the thalamus, caudate, and MLC in PD patients compared to controls.
• Thalamic DTI changes correlated with gait pace parameters (e.g., Timed Up and Go) in the medication ON state.
• Caudate DTI changes correlated with cadence and stride time in the medication OFF state.

Conclusions:

• PD is associated with distinct regional microstructural degradation in key locomotion control areas.
• DTI findings suggest a failure within the subcortical locomotion network in PD.
• DTI ROI analysis shows potential as a tool for assessing PD functional status and gait deficits, possibly serving as an imaging biomarker.