Characterizing Deep Brain Stimulation Dual Device Beat Frequency Artifacts

Area of Science:

• Neuroscience
• Biomedical Engineering

Background:

• Recording-enabled deep brain stimulation (DBS) devices treat neurological disorders.
• Current DBS systems are limited to two brain leads, necessitating bilateral implantable pulse generators (IPGs) for research.
• Mismatched clock rates between dual IPGs cause beat frequency artifacts (BFAs), contaminating neural signals.

Purpose of the Study:

• To quantify beat frequency artifact (BFA) intervals in local field potential (LFP) recordings from patients with dual implantable pulse generators (IPGs).
• To investigate the impact of continuous DBS (cDBS) and adaptive DBS (aDBS) on BFA intervals.
• To identify challenges and propose strategies for adaptive DBS algorithm development in dual-device scenarios.

Main Methods:

• Analyzed LFP recordings from 26 patients with dual IPGs.
• Quantified BFA intervals during both continuous DBS (cDBS) and adaptive DBS (aDBS) modes.
• Assessed the relationship between stimulation frequency mismatches and BFA intervals.

Main Results:

• BFAs occurred in all patients when both IPGs were active, with intervals ranging from 112 seconds to 30 minutes.
• Smaller stimulation frequency differences correlated with longer BFA intervals.
• Switching to aDBS reduced the BFA interval to 30 seconds in one patient.

Conclusions:

• BFAs are an inherent challenge in dual-device DBS, arising from stimulation frequency mismatches.
• BFAs must be considered in LFP analysis and adaptive DBS algorithm design.
• Mitigation strategies, such as careful channel selection and timing adjustments, are crucial for future aDBS development.