Sensing-enabled hippocampal deep brain stimulation in idiopathic nonhuman primate epilepsy

Area of Science:

• Neuroscience
• Neurology
• Biomedical Engineering

Background:

• Epilepsy affects 1% of the global population, with 30% of patients unresponsive to medication.
• Deep brain stimulation (DBS) presents a promising alternative treatment for refractory epilepsy.
• A modified clinical DBS platform (PC+S) enables long-term neural recording for studying DBS effects.

Purpose of the Study:

• To report the first use of the PC+S device for characterizing idiopathic epilepsy in a nonhuman primate (NHP).
• To assess the effects of DBS on neural networks in an epileptic NHP model.
• To validate real-time ictal event detection using the PC+S system.

Main Methods:

• Clinical DBS electrodes were bilaterally implanted in the hippocampus of an epileptic NHP.
• Local field potential (LFP) recordings were collected using the PC+S system for seizure characterization.
• Stimulation parameters were varied to observe effects on LFP activity and seizure induction under anesthesia and in awake conditions.

Main Results:

• The PC+S system demonstrated real-time automatic detection of ictal events, validated by behavioral observation.
• Seizures were characterized by 8- to 25-Hz oscillations originating from the right hemisphere and generalizing.
• Stimulation parameters influenced LFP activity, causing suppression or seizure induction; chronic stimulation effects on seizure activity were evaluated.

Conclusions:

• This study presents the first electrophysiological characterization of epilepsy using a next-generation clinical DBS system with chronic recording capabilities.
• The findings provide crucial insights into the therapeutic mechanisms of DBS for epilepsy.
• Results will guide further development of DBS technology for epilepsy treatment.