Brain Plasticity in Charcot-Marie-Tooth Type 1A Patients? A Combined Structural and Diffusion MRI Study

Area of Science:

• Neuroscience
• Neurology
• Radiology

Background:

• Peripheral neuropathies, like Charcot-Marie-Tooth (CMT) disease, can involve the central nervous system.
• Understanding brain changes in CMT1A is crucial for comprehending disease mechanisms and potential therapeutic targets.

Purpose of the Study:

• To investigate structural brain modifications in Charcot-Marie-Tooth type 1A (CMT1A) patients using volumetric MRI and diffusion tensor imaging (DTI).
• To explore correlations between observed brain changes and clinical/electrophysiological measures in CMT1A.

Main Methods:

• Prospective cross-sectional study involving 20 CMT1A patients and 20 healthy controls (May 2017-May 2019).
• Acquisition of 3T MRI brain scans, including volumetric MRI and DTI.
• Analyses included Voxel-Based Morphometry (VBM) and Tract-Based Spatial Statistics (TBSS), with age, sex, and intracranial volume as covariates.
• Correlation analysis between brain metrics and clinical/electrophysiological data.

Main Results:

• VBM analysis showed significantly increased gray matter (GM) volume in CMT1A patients compared to controls in bilateral cerebellar lobules III-VI and the left hippocampus (p=0.04).
• No significant differences in DTI metrics were found between groups.
• A negative correlation was observed between ulnar compound motor action potential and the GM volume in the right cerebellum (r=-0.502, p=0.03).

Conclusions:

• CMT1A patients exhibit structural brain reorganization, specifically increased GM volume in the cerebellum and hippocampus.
• These findings suggest potential neural plasticity mechanisms compensating for peripheral nerve pathology.
• Brain structural changes may modulate the impact of axonal degeneration on functional impairment in CMT1A.