Stereo-Electroencephalography-Guided Network Neuromodulation for Psychiatric Disorders: The Neurophysiology Monitoring Unit

Abstract

Background and objectives: Recent advances in stereotactic and functional neurosurgery have brought forth the stereo-electroencephalography approach which allows deeper interrogation and characterization of the contributions of deep structures to neural and affective functioning. We argue that this approach can and should be brought to bear on the notoriously intractable issue of defining the pathophysiology of refractory psychiatric disorders and developing patient-specific optimized stimulation therapies.

Methods: We have developed a suite of methods for maximally leveraging the stereo-electroencephalography approach for an innovative application to understand affective disorders, with high translatability across the broader range of refractory neuropsychiatric conditions.

Results: This article provides a roadmap for determining desired electrode coverage, tracking high-resolution research recordings across a large number of electrodes, synchronizing intracranial signals with ongoing research tasks and other data streams, applying intracranial stimulation during recording, and design choices for patient comfort and safety.

Conclusion: These methods can be implemented across other neuropsychiatric conditions needing intensive electrophysiological characterization to define biomarkers and more effectively guide therapeutic decision-making in cases of severe and treatment-refractory disease.

FIGURE 1.

Cabling diagram demonstrates the connections between the implanted leads and the stimulation device (Cerestim), the recording system (NSP), and the clinical monitoring system (NK amplifier). BosSci, Boston Scientific; BR, blackrock microsystems; DBS, deep brain stimulation; NK, Nihon-Kohden; NSP, neural signal processor; sEEG, stereo-electroencephalography.

FIGURE 2.

Cabling configurations for primary recording positions in the example use case. Method 1 was used in the case of stimulation being delivered to all DBS leads within a session or simultaneously. Method 2 allowed stimulation to a single DBS lead with simultaneous recording of the remaining leads. Amp, amplifier; DBS, deep brain stimulation; l, left; r, right; SCC, subcallosal cingulate; VC/VS, ventral capsule/ventral striatum.

FIGURE 3.

Three-dimensional rendering of all sEEG and DBS leads projected into transparent brain image. All contacts are colored by region of interest: VC/VS, SCC, ACC, dlPFC, vmPFC, mOFC, lOFC, and amygdala. Contacts in both gray matter and white matter are visualized. ACC, anterior cingulate cortex; DBS, deep brain stimulation; dlPFC, dorsolateral prefrontal cortex; lOFC, lateral orbitofrontal cortex; mOFC, medial orbitofrontal cortex; SCC, subcallosal cingulate; sEEG, stereo-electroencephalography; VC/VS, ventral capsulse/ventral striatum; vmPFC, ventromedial prefrontal cortex.