[Brain mapping in Parkinson disease treated by cryothalamotomy]

Area of Science:

• Neuroscience
• Neurology
• Biomedical Engineering

Context:

• Parkinson's disease (PD) is a neurodegenerative disorder affecting motor control.
• Cryothalamotomy is a surgical procedure targeting the thalamus to alleviate PD symptoms.
• Conventional electroencephalography (EEG) often shows subtle changes in PD patients.

Purpose:

• To investigate the effects of cryothalamotomy on cerebral bioelectric activity in Parkinson's disease patients using Brain Electrical Activity Mapping (BEAM).
• To correlate observed changes in brain activity with clinical motor improvements and cognitive status.

Summary:

• BEAM analysis of 20 Parkinson's disease patients after cryothalamotomy revealed significant hemispheric asymmetry in alpha and beta frequency bands.
• The operated hemisphere showed a dominant, lower-frequency, higher-amplitude alpha rhythm, suggesting a unilateral synchronizing effect of thalamotomy.
• The intact hemisphere exhibited a faster beta rhythm and irregular alpha activity.
• In advanced cases, diffused slow waves in frontal regions correlated with mental insufficiency.

Impact:

• Findings suggest cryothalamotomy exerts a unilateral synchronizing influence on brain activity, potentially explaining motor functional improvements.
• BEAM offers a more detailed assessment of cerebral bioelectric changes post-thalamotomy compared to conventional EEG.
• Identifies potential electrophysiological markers for cognitive decline in advanced Parkinson's disease.