Locating the STN-DBS electrodes and resolving their subsequent networks using coherent source analysis on EEG

Area of Science:

• Neuroscience
• Biomedical Engineering
• Clinical Neurology

Background:

• Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is a leading surgical treatment for Parkinson's disease (PD).
• Accurate electrode placement is crucial for effective STN-DBS therapy.
• Understanding the brain networks involved in tremor is essential for PD management.

Purpose of the Study:

• To determine the feasibility of using electroencephalography (EEG) source analysis to precisely locate the STN-DBS electrode.
• To identify brain regions associated with tremor in Parkinson's disease patients undergoing STN-DBS.
• To investigate the functional network modulated by STN-DBS.

Main Methods:

• Dynamic Imaging of Coherent Sources (DICS) was employed for EEG source analysis.
• Simulations with model dipoles were conducted to assess the accuracy of deep source localization.
• Power spectrum analysis was performed on EEG data from PD patients receiving STN-DBS.

Main Results:

• EEG source analysis successfully located the STN within the diencephalon region.
• Simulations validated the capability of source analysis to detect deep brain structures.
• Parkinsonian tremor patients exhibited a distinct peak at the stimulation frequency and its harmonics in their power spectrum.
• STN-DBS modulated a network including the sensory motor cortex, supplementary motor area, prefrontal cortex, diencephalon, cerebellum, and brainstem.

Conclusions:

• EEG source analysis, specifically DICS, is a viable method for localizing the STN in PD patients undergoing DBS.
• The study identified a widespread brain network affected by STN-DBS, offering insights into tremor pathophysiology.
• These findings contribute to a better understanding of the neural mechanisms underlying tremor in Parkinson's disease.