MRI correlates of Parkinson's disease progression: a voxel based morphometry study

Area of Science:

• Neuroscience
• Neurology
• Medical Imaging

Background:

• Parkinson's disease (PD) is a neurodegenerative disorder primarily affecting motor function.
• Structural brain changes, particularly gray matter (GM) volume loss, are implicated in PD progression.
• Understanding the spatiotemporal pattern of these changes is crucial for early diagnosis and intervention.

Purpose of the Study:

• To investigate structural brain differences in early-mild Parkinson's disease (PD) patients compared to healthy controls.
• To track the progression of gray matter (GM) volume changes over a two-year follow-up period in PD patients.
• To identify specific brain regions affected early and throughout the progression of PD.

Main Methods:

• Voxel-based morphometry (VBM), a fully automated technique for objective whole-brain analysis.
• Comparison of GM volumes between 20 mild PD patients and 15 healthy controls at baseline and after 2 years.
• Identification of regional differences in GM volume between the groups.

Main Results:

• PD patients showed decreased GM volumes in the right putamen and right parietal cortex compared to controls.
• After two years, PD patients exhibited persistent GM loss in the putamen and parietal cortex.
• Significant GM loss was also observed in the pedunculopontine nucleus (PPN) and mesencephalic locomotor region (MLR) in PD patients over time.

Conclusions:

• Parkinson's disease is associated with widespread morphological brain changes in both cortical and subcortical structures.
• The parietal cortex and putamen appear to be among the first brain regions affected in PD.
• Progressive atrophy in the inferior-posterior midbrain, including the PPN and MLR, is a key feature of PD progression, offering insights into disease mechanisms.