Human Cervical Epidural Spinal Electrogram Topographically Maps Distinct Volitional Movements.

Little is known about the electrophysiologic activity of the intact human spinal cord during volitional movement. We analyzed epidural spinal recordings from a total of 5 human subjects of both sexes during a variety of upper extremity movements and found that these spinal epidural electrograms contain spectral information distinguishing periods of movement, rest, and sensation. Cervical epidural electrograms also contained spectral changes time-locked with movement. We found that these changes were primarily associated with increased power in the theta (4-8 Hz) band, feature increased theta-gamma phase-amplitude coupling, and that this increase in theta power can be used to topographically map distinct upper extremity movements onto the cervical spinal cord in accordance with established myotome maps of the upper extremity. Our findings have implications for the development of neurostimulation protocols and devices focused on motor rehabilitation for the upper extremity and the approach presented here may facilitate spatiotemporal mapping of naturalistic movements.Significance statement The electrophysiology of the human spinal cord remains incompletely characterized. We build on our previous work in describing a novel method of recording spinal epidural electrograms from awake human participants by showing that SEGs (spinal electrograms) recorded from the cervical spinal cord during volitional upper extremity movements demonstrate spectral changes time-locked to movement that feature prominent increase in theta band power, theta-gamma phase-amplitude coupling, and are well delineated from pre-movement baseline. These spectral changes can also be topographically mapped to the cervical spine in a myotome distribution broadly consistent with maps generated from intraoperative stimulation studies in humans and direct stimulation experiments in monkeys. Our methodology may aid in the developing spatiotemporal maps for neurostimulation protocols to recapitulate naturalistic movements.

A cost analysis of MR-guided laser interstitial thermal therapy for adult refractory epilepsy.

OBJECTIVE: MR-guided laser interstitial thermal therapy (LITT) is used increasingly for refractory epilepsy. The goal of this investigation is to directly compare cost and short-term adverse outcomes for adult refractory epilepsy treated with temporal lobectomy and LITT, as well as to identify risk factors for increased costs and adverse outcomes. METHODS: The National Inpatient Sample (NIS) was queried for patients who received LITT between 2012 and 2019. Patients with adult refractory epilepsy were identified. Multivariable mixed-effects models were used to analyze predictors of cost, length of stay (LOS), and complications. RESULTS: LITT was associated with reduced LOS and overall cost relative to temporal lobectomy, with a statistical trend toward lower incidence of postoperative complications. High-volume surgical epilepsy centers had lower LOS overall. Longer LOS was a significant driver of increased cost for LITT, and higher comorbidity was associated with non-routine discharge. SIGNIFICANCE: LITT is an affordable alternative to temporal lobectomy for adult refractory epilepsy with an insignificant reduction in inpatient complications. Patients may benefit from expanded access to this treatment modality for both its reduced LOS and lower cost.

Epidural Spinal Electrogram Provides Direct Spinal Recordings in Awake Human Participants.

Little is known about the electrophysiological activity of the spinal cord during voluntary movement control in humans. We present a novel method for recording electrophysiological activity from the human spinal cord using implanted epidural electrodes during naturalistic movements including overground walking. Spinal electrograms (SEGs) were recorded from epidural electrodes implanted as part of a test trial for patients with chronic pain undergoing evaluation for spinal cord stimulation. Externalized ends of the epidural leads were connected to an external amplifier to capture SEGs. Electromyographic and accelerometry data from the upper and lower extremities were collected using wireless sensors and synchronized to the SEG data. Patients were instructed to perform various arm and leg movements while SEG and kinematic data were collected. This study proves the safety and feasibility of performing epidural spinal recordings from human subjects performing movement tasks.