Quantitative Susceptibility Mapping Changes Relate to Gait Issues in Parkinson's Disease

Area of Science:

• Neuroimaging
• Neurology
• Biomedical Engineering

Background:

• Quantitative susceptibility mapping (QSM) shows increased iron in the basal ganglia of Parkinson's disease (PD) patients.
• The relationship between QSM findings and gait disturbances, such as freezing of gait (FOG), remains understudied in PD.

Purpose of the Study:

• To investigate the association between QSM-derived iron levels in basal ganglia and extra-basal ganglia structures and gait impairments in PD patients.
• To compare QSM values between PD patients and cognitively unimpaired (CU) individuals.

Main Methods:

• A case-control study involving 29 PD and 27 CU participants.
• Whole-brain QSM acquired at 3T, with manual region of interest (ROI) delineation in key brain structures.
• Comparison of ROI susceptibilities between groups and correlation with qualitative (FOG questionnaire) and quantitative gait measures.

Main Results:

• No significant differences in QSM susceptibility were found between PD and CU groups overall.
• PD patients with gait impairment exhibited higher susceptibility in the putamen, red nucleus, and caudate nucleus compared to those without gait impairment.
• PD patients with FOG showed significantly higher susceptibility in the globus pallidus compared to those without FOG.

Conclusions:

• Brain iron levels, as measured by QSM in basal ganglia and other structures, are linked to gait impairment and FOG in Parkinson's disease.
• QSM may serve as a potential imaging biomarker for gait disturbances in PD.