Stability of infraslow correlation structure in time-shifted intracranial EEG signals.

It is increasingly understood that the epilepsies are characterized by network pathology that can span multiple spatial and temporal scales. Recent work indicates that infraslow (<0.2 Hz) envelope correlations may form a basis for distant spatial coupling in the brain.

Cellular recovery after prolonged warm ischaemia of the whole body.

After cessation of blood flow or similar ischaemic exposures, deleterious molecular cascades commence in mammalian cells, eventually leading to their death. Yet with targeted interventions, these processes can be mitigated or reversed, even minutes or hours post mortem, as also reported in the isolated porcine brain using BrainEx technology. To date, translating single-organ interventions to intact, whole-body applications remains hampered by circulatory and multisystem physiological challenges.

Artificial neural network trained on smartphone behavior can trace epileptiform activity in epilepsy.

A range of abnormal electrical activity patterns termed epileptiform discharges can occur in the brains of persons with epilepsy. These epileptiform discharges can be monitored and recorded with implanted devices that deliver therapeutic neurostimulation. These continuous recordings provide an opportunity to study the behavioral correlates of epileptiform discharges as the patients go about their daily lives.

Video quality using outpatient smartphone videos in epilepsy: Results from the OSmartViE study.

Background And Purpose: The aim of this study was to evaluate the quality of smartphone videos (SVs) of neurologic events in adult epilepsy outpatients. The use of home video recording in patients with neurological disease states is increasing. Experts interpretation of outpatient smartphone videos of seizures and neurological events has demonstrated similar diagnostic accuracy to inpatient video-electroencephalography (EEG) monitoring.

Nine-year prospective efficacy and safety of brain-responsive neurostimulation for focal epilepsy.

Objective: To prospectively evaluate safety and efficacy of brain-responsive neurostimulation in adults with medically intractable focal onset seizures (FOS) over 9 years.

Methods: Adults treated with brain-responsive neurostimulation in 2-year feasibility or randomized controlled trials were enrolled in a long-term prospective open label trial (LTT) to assess safety, efficacy, and quality of life (QOL) over an additional 7 years. Safety was assessed as adverse events (AEs), efficacy as median percent change in seizure frequency and responder rate, and QOL with the Quality of Life in Epilepsy (QOLIE-89) inventory.

Beyond implantation effect? Long-term seizure reduction and freedom following intracranial monitoring without additional surgical interventions.

The term 'implantation effect' is used to describe an immediate and transient improvement in seizure frequency following an intracranial study for seizure onset localization. We conducted a retrospective analysis of 190 consecutive patients undergoing intracranial electroencephalogram (EEG) monitoring, of whom 41 had no subsequent resection/ablation/stimulation; 33 had adequate data and follow-up time available for analysis. Analysis of seizure frequency following an intracranial study showed 36% (12/33) responder rate (>50% seizure reduction) at one year, decreasing and stabilizing at 20% from year 4 onwards.

Assessment of the Predictive Value of Outpatient Smartphone Videos for Diagnosis of Epileptic Seizures.

Importance: Misdiagnosis of epilepsy is common. Video electroencephalogram provides a definitive diagnosis but is impractical for many patients referred for evaluation of epilepsy.

Objective: To evaluate the accuracy of outpatient smartphone videos in epilepsy.

Seizure susceptibility and infraslow modulatory activity in the intracranial electroencephalogram.

Objective: Studies of infraslow amplitude modulations (<0.15 Hz) of band power time series suggest that these envelope correlations may form a basis for distant spatial coupling in the brain. In this study, we sought to determine how infraslow relationships are affected by antiepileptic drug (AED) taper, time of day, and seizure.

Sudden unexpected death in epilepsy in patients treated with brain-responsive neurostimulation.

Objective: To study the incidence and clinical features of sudden unexpected death in epilepsy (SUDEP) in patients treated with direct brain-responsive stimulation with the RNS System.

Methods: All deaths in patients treated in clinical trials (N = 256) or following U.S.

Brain-responsive neurostimulation in patients with medically intractable mesial temporal lobe epilepsy.

Objective: Evaluate the seizure-reduction response and safety of mesial temporal lobe (MTL) brain-responsive stimulation in adults with medically intractable partial-onset seizures of mesial temporal lobe origin.

Methods: Subjects with mesial temporal lobe epilepsy (MTLE) were identified from prospective clinical trials of a brain-responsive neurostimulator (RNS System, NeuroPace). The seizure reduction over years 2-6 postimplantation was calculated by assessing the seizure frequency compared to a preimplantation baseline.

Brain-responsive neurostimulation in patients with medically intractable seizures arising from eloquent and other neocortical areas.

Objective: Evaluate the seizure-reduction response and safety of brain-responsive stimulation in adults with medically intractable partial-onset seizures of neocortical origin.

Methods: Patients with partial seizures of neocortical origin were identified from prospective clinical trials of a brain-responsive neurostimulator (RNS System, NeuroPace). The seizure reduction over years 2-6 postimplantation was calculated by assessing the seizure frequency compared to a preimplantation baseline.

Regional and network relationship in the intracranial EEG second spectrum.

Objective: We examined low-frequency amplitude modulations of band power time-series, i.e. the second spectrum, of the intracranial EEG (icEEG) for evidence of support for spatial relationships between different parts of the brain and within the default mode network (DMN).

The relationship between seizures, interictal spikes and antiepileptic drugs.

Objective: A considerable decrease in spike rate accompanies antiepileptic drug (AED) taper during intracranial EEG (icEEG) monitoring. Since spike rate during icEEG monitoring can be influenced by surgery to place intracranial electrodes, we studied spike rate during long-term scalp EEG monitoring to further test this observation.

Methods: We analyzed spike rate, seizure occurrence and AED taper in 130 consecutive patients over an average of 8.

Progressive change in sleep over multiple nights of intracranial EEG monitoring.

Objective: We evaluated changes to sleep structure during continuous intracranial EEG (icEEG) monitoring of epilepsy patients undergoing localization of the seizure onset area.

Methods: We studied 28 adult epilepsy patients who underwent icEEG monitoring for a median of 12 nights. We used a metric calculated from relative delta power (RDP) to evaluate the emergence of sleep cycles for every night of monitoring.

50 Hz hippocampal stimulation in refractory epilepsy: Higher level of basal glutamate predicts greater release of glutamate.

Objective: The effect of electrical stimulation on brain glutamate release in humans is unknown. Glutamate is elevated at baseline in the epileptogenic hippocampus of patients with refractory epilepsy, and increases during spontaneous seizures. We examined the effect of 50 Hz stimulation on glutamate release and its relationship to interictal levels in the hippocampus of patients with epilepsy.

Long-term treatment with responsive brain stimulation in adults with refractory partial seizures.

Objective: The long-term efficacy and safety of responsive direct neurostimulation was assessed in adults with medically refractory partial onset seizures.

Methods: All participants were treated with a cranially implanted responsive neurostimulator that delivers stimulation to 1 or 2 seizure foci via chronically implanted electrodes when specific electrocorticographic patterns are detected (RNS System). Participants had completed a 2-year primarily open-label safety study (n = 65) or a 2-year randomized blinded controlled safety and efficacy study (n = 191); 230 participants transitioned into an ongoing 7-year study to assess safety and efficacy.

The spatial and signal characteristics of physiologic high frequency oscillations.

Objectives: To study the incidence, spatial distribution, and signal characteristics of high frequency oscillations (HFOs) outside the epileptic network.

Methods: We included patients who underwent invasive evaluations at Yale Comprehensive Epilepsy Center from 2012 to 2013, had all major lobes sampled, and had localizable seizure onsets. Segments of non-rapid eye movement (NREM) sleep prior to the first seizure were analyzed.

Two-year seizure reduction in adults with medically intractable partial onset epilepsy treated with responsive neurostimulation: final results of the RNS System Pivotal trial.

Objective: To demonstrate the safety and effectiveness of responsive stimulation at the seizure focus as an adjunctive therapy to reduce the frequency of seizures in adults with medically intractable partial onset seizures arising from one or two seizure foci.

Methods: Randomized multicenter double-blinded controlled trial of responsive focal cortical stimulation (RNS System). Subjects with medically intractable partial onset seizures from one or two foci were implanted, and 1 month postimplant were randomized 1:1 to active or sham stimulation.

7T MR spectroscopic imaging in the localization of surgical epilepsy.

Purpose: With the success that surgical approaches can provide for localization-related epilepsy, accurate seizure localization remains important. Although magnetic resonance (MR) spectroscopy has had success in earlier studies in medial temporal lobe epilepsy, there have been fewer studies evaluating its use in a broader range of localization-related epilepsy. With improvements in signal-to-noise with ultra-high field MR, we report on the use of high resolution 7T MR spectroscopic imaging (MRSI) in 25 surgically treated patients studied over a 3.

Intracranially recorded interictal spikes: relation to seizure onset area and effect of medication and time of day.

Objective: The relationship between seizures and interictal spikes remains undetermined. We analyzed intracranial EEG (icEEG) recordings to examine the relationship between the seizure onset area and interictal spikes.

Methods: 80 unselected patients were placed into 5 temporal, 4 extratemporal, and one unlocalized groups based on the location of the seizure onset area.

Intracranial EEG evaluation of relationship within a resting state network.

Objective: We tested if a relationship between distant parts of the default mode network (DMN), a resting state network defined by fMRI studies, can be observed with intracranial EEG recorded from patients with localization-related epilepsy.

Methods: Magnitude squared coherence, mutual information, cross-approximate entropy, and the coherence of the gamma power time-series were estimated, for one hour intracranial EEG recordings of background activity from 9 patients, to evaluate the relationship between two test areas which were within the DMN (anterior cingulate and orbital frontal, denoted as T1 and posterior cingulate and mesial parietal, denoted as T2), and one control area (denoted as C), which was outside the DMN. We tested if the relationship between T1 and T2 was stronger than the relationship between each of these areas and C.

A prospective study of loss of consciousness in epilepsy using virtual reality driving simulation and other video games.

Patients with epilepsy are at risk of traffic accidents when they have seizures while driving. However, driving is an essential part of normal daily life in many communities, and depriving patients of driving privileges can have profound consequences for their economic and social well-being. In the current study, we collected ictal performance data from a driving simulator and two other video games in patients undergoing continuous video/EEG monitoring.

Background intracranial EEG spectral changes with anti-epileptic drug taper.

Objective: Previous studies have revealed a surprising decrease in spike counts and Teager energy between on- and off-AEDs states during intracranial EEG (icEEG) monitoring. Here, we expand the measures evaluated to icEEG power and frequency band power.

Methods: Two icEEG epochs, on- and off-AEDs, each 1h in duration, were studied for each of 21 unselected adult patients.