2021
Increased branched‐chain amino acids at baseline and hours before a spontaneous seizure in the human epileptic brain
Ong C, Damisah EC, Gruenbaum SE, Dhaher R, Deng Y, Sandhu MRS, Zaveri HP, Spencer DD, Eid T. Increased branched‐chain amino acids at baseline and hours before a spontaneous seizure in the human epileptic brain. Epilepsia 2021, 62: e88-e97. PMID: 33949690, PMCID: PMC11259155, DOI: 10.1111/epi.16920.Peer-Reviewed Original ResearchMeSH KeywordsAdolescentAdultAmino Acids, Branched-ChainBrain ChemistryChildChild, PreschoolChromatography, High Pressure LiquidDrug Resistant EpilepsyElectrocorticographyElectroencephalographyEpilepsies, PartialExtracellular SpaceFemaleGlutamic AcidHumansIsoleucineMaleMicrodialysisMiddle AgedSeizuresTandem Mass SpectrometryYoung AdultConceptsSpontaneous seizuresDrug-resistant focal epilepsyExtracellular brain glutamateHuman epileptic brainBranched-chain amino acidsBranched chain amino acids valineRefractory epilepsyBrain microdialysisGlutamatergic neurotransmissionFocal epilepsySeizure onsetBrain glutamateEpileptic brainHuman patientsSeizuresBrain regionsDialysis samplesMammalian targetEpilepsyLiquid chromatography-tandem mass spectrometryBaselineBCAAIntracranial electroencephalographyChromatography-tandem mass spectrometryPatients
2020
Beyond implantation effect? Long-term seizure reduction and freedom following intracranial monitoring without additional surgical interventions
Percy J, Zaveri H, Duckrow RB, Gerrard J, Farooque P, Hirsch LJ, Spencer DD, Sivaraju A. Beyond implantation effect? Long-term seizure reduction and freedom following intracranial monitoring without additional surgical interventions. Epilepsy & Behavior 2020, 111: 107231. PMID: 32615416, DOI: 10.1016/j.yebeh.2020.107231.Peer-Reviewed Original ResearchConceptsLong-term seizure freedomSeizure freedomSeizure frequencyElectrode implantationIntracranial studiesLong-term seizure reductionAdditional surgical interventionSeizure onset localizationIntracranial electroencephalogram monitoringSeizure reductionConsecutive patientsSurgical interventionEpileptogenic networksElectroencephalogram monitoringNeuromodulatory effectsRetrospective analysisIntracranial monitoringTransient improvementDepth electrodesPatientsYear 4ImplantationAdequate dataYears
2018
Resting state connectivity in neocortical epilepsy: The epilepsy network as a patient-specific biomarker
Marino AC, Yang GJ, Tyrtova E, Wu K, Zaveri HP, Farooque P, Spencer DD, Bandt SK. Resting state connectivity in neocortical epilepsy: The epilepsy network as a patient-specific biomarker. Clinical Neurophysiology 2018, 130: 280-288. PMID: 30605890, DOI: 10.1016/j.clinph.2018.11.016.Peer-Reviewed Original ResearchConceptsLocalization related epilepsyEpilepsy networkSeizure onset locationSingle-patient levelCorrelated network activityPatient-specific biomarkersRelated epilepsyConnectivity patternsNeocortical epilepsyPatient levelSeizure onsetInterictal periodAnatomic locationPatientsPossible biomarkersState connectivityCortical regionsSingle-subject levelTopographic distributionCohortNetwork disorderBrain networksEpilepsyNetwork activityBiomarkers
2016
Regional and network relationship in the intracranial EEG second spectrum
Joshi RB, Gaspard N, Goncharova II, Duckrow RB, Duncan D, Gerrard JL, Spencer DD, Hirsch LJ, Zaveri HP. Regional and network relationship in the intracranial EEG second spectrum. Clinical Neurophysiology 2016, 127: 3485-3491. PMID: 27692590, DOI: 10.1016/j.clinph.2016.09.003.Peer-Reviewed Original ResearchThe relationship between seizures, interictal spikes and antiepileptic drugs
Goncharova II, Alkawadri R, Gaspard N, Duckrow RB, Spencer DD, Hirsch LJ, Spencer SS, Zaveri HP. The relationship between seizures, interictal spikes and antiepileptic drugs. Clinical Neurophysiology 2016, 127: 3180-3186. PMID: 27292227, DOI: 10.1016/j.clinph.2016.05.014.Peer-Reviewed Original ResearchConceptsFirst seizureSeizure occurrenceAED taperSpike rateEEG monitoringMarker of inhibitionIntracranial EEG monitoringOccurrence of seizuresScalp EEG monitoringConsecutive patientsAntiepileptic drugsDrug taperHigh spike ratesInterictal spikesSeizuresDay 4Intracranial electrodesPatientsAEDsSignificant relationshipProgressive change in sleep over multiple nights of intracranial EEG monitoring
Joshi RB, Gaspard N, Goncharova II, Pavlova M, Duckrow RB, Gerrard JL, Spencer DD, Hirsch LJ, Zaveri HP. Progressive change in sleep over multiple nights of intracranial EEG monitoring. Clinical Neurophysiology 2016, 127: 2302-2307. PMID: 27072103, DOI: 10.1016/j.clinph.2016.02.018.Peer-Reviewed Original Research50 Hz hippocampal stimulation in refractory epilepsy: Higher level of basal glutamate predicts greater release of glutamate
Cavus I, Widi GA, Duckrow RB, Zaveri H, Kennard JT, Krystal J, Spencer DD. 50 Hz hippocampal stimulation in refractory epilepsy: Higher level of basal glutamate predicts greater release of glutamate. Epilepsia 2016, 57: 288-297. PMID: 26749134, DOI: 10.1111/epi.13269.Peer-Reviewed Original ResearchConceptsBasal glutamate levelsRefractory epilepsyGlutamate effluxBasal glutamateGlutamate levelsElectrical stimulationEpileptic hippocampusGlutamate releaseSeizure groupHz stimulationBrain glutamate releaseHippocampus of patientsStimulation-induced increaseEpilepsy monitoring unitStimulation-induced changesEpileptogenic hippocampusInduced seizuresSeizure inductionSpontaneous seizuresInterictal levelsGlutamate increaseAtrophic hippocampusElectroencephalography evaluationHippocampal stimulationHippocampal electrodes
2014
The spatial and signal characteristics of physiologic high frequency oscillations
Alkawadri R, Gaspard N, Goncharova II, Spencer DD, Gerrard JL, Zaveri H, Duckrow RB, Blumenfeld H, Hirsch LJ. The spatial and signal characteristics of physiologic high frequency oscillations. Epilepsia 2014, 55: 1986-1995. PMID: 25470216, PMCID: PMC5123742, DOI: 10.1111/epi.12851.Peer-Reviewed Original ResearchConceptsPhysiologic high-frequency oscillationsSeizure onsetEpileptic networkNon-rapid eye movement sleepComprehensive Epilepsy CenterMesial temporal structuresEye movement sleepHigh-frequency oscillationsHighest HFO ratesFirst seizureInvasive evaluationEpilepsy centersIntracranial evaluationMovement sleepPerirolandic regionEpileptiform dischargesParietooccipital regionOccipital lobeEpileptic sitesPatientsNonepileptic regionsPhysiologic eventsFast ripplesHFO ratesLonger duration
2013
Intracranially recorded interictal spikes: Relation to seizure onset area and effect of medication and time of day
Goncharova II, Spencer SS, Duckrow RB, Hirsch LJ, Spencer DD, Zaveri HP. Intracranially recorded interictal spikes: Relation to seizure onset area and effect of medication and time of day. Clinical Neurophysiology 2013, 124: 2119-2128. PMID: 23856192, DOI: 10.1016/j.clinph.2013.05.027.Peer-Reviewed Original ResearchIntracranial EEG evaluation of relationship within a resting state network
Duncan D, Duckrow RB, Pincus SM, Goncharova I, Hirsch LJ, Spencer DD, Coifman RR, Zaveri HP. Intracranial EEG evaluation of relationship within a resting state network. Clinical Neurophysiology 2013, 124: 1943-1951. PMID: 23790525, DOI: 10.1016/j.clinph.2013.03.028.Peer-Reviewed Original ResearchConceptsDefault mode networkIntracranial EEG evaluationMode networkLocalization-related epilepsyCross-approximate entropyNeuronal involvementHemodynamic measurementsIntracranial EEG recordingsEEG evaluationBackground activityGamma powerFMRI studyIntracranial EEGBrain activityPatientsEEG recordingsLow levelsT2EpilepsyMagnitude squared coherenceT1
2010
Patient and caregiver perspectives on seizure prediction
Arthurs S, Zaveri HP, Frei MG, Osorio I. Patient and caregiver perspectives on seizure prediction. Epilepsy & Behavior 2010, 19: 474-477. PMID: 20851054, DOI: 10.1016/j.yebeh.2010.08.010.Peer-Reviewed Original Research
2009
Intracranial EEG power and metabolism in human epilepsy
Pan JW, Zaveri HP, Spencer DD, Hetherington HP, Spencer SS. Intracranial EEG power and metabolism in human epilepsy. Epilepsy Research 2009, 87: 18-24. PMID: 19699059, PMCID: PMC2783857, DOI: 10.1016/j.eplepsyres.2009.07.006.Peer-Reviewed Original ResearchConceptsMesial temporal lobe epilepsyNAA/CrMesial temporal lobeNeocortical epilepsySeizure onset zoneN-acetyl aspartateHigh-frequency activityTemporal lobeOnset zoneFrequency activityMetabolic imagingIntracranial EEG analysisTemporal lobe epilepsyEEG powerQuantitative EEG measuresLobe epilepsySame anatomical regionMTLE groupSeizure localizationHuman epilepsyTissue injuryEpilepsy patientsHuman studiesAbnormal manifestationsEpilepsySpatial distribution of intracranially recorded spikes in medial and lateral temporal epilepsies
Goncharova II, Zaveri HP, Duckrow RB, Novotny EJ, Spencer SS. Spatial distribution of intracranially recorded spikes in medial and lateral temporal epilepsies. Epilepsia 2009, 50: 2575-2585. PMID: 19674048, DOI: 10.1111/j.1528-1167.2009.02258.x.Peer-Reviewed Original ResearchConceptsMedial temporal structuresInterictal spikesLT patientsCortical areasNeocortical seizure onsetsSleep-related increaseSpike rateLateral temporal epilepsyExtratemporal areasTemporal epilepsySeizure onsetIntracranial monitoringLT groupMT groupPatientsFrontal spikesSeizuresGreater numberSleepGroupTemporal structureEpilepsySpikes
2008
Decreased hippocampal volume on MRI is associated with increased extracellular glutamate in epilepsy patients
Cavus I, Pan JW, Hetherington HP, Abi‐Saab W, Zaveri HP, Vives KP, Krystal JH, Spencer SS, Spencer DD. Decreased hippocampal volume on MRI is associated with increased extracellular glutamate in epilepsy patients. Epilepsia 2008, 49: 1358-1366. PMID: 18410365, DOI: 10.1111/j.1528-1167.2008.01603.x.Peer-Reviewed Original ResearchConceptsTemporal lobe epilepsyHippocampal volumeClinical factorsHippocampal atrophyEpileptogenic hippocampusGABA levelsNeurochemical levelsElevated extracellular glutamate levelsContralateral hippocampal volumeIntracranial EEG evaluationMedication-resistant epilepsyRefractory TLE patientsHigh seizure frequencyRelevant clinical factorsSmaller hippocampal volumesExtracellular glutamate levelsFebrile seizure historyTreatment of epilepsySeizure frequencyLobe epilepsySeizure historyTLE patientsAtrophic hippocampusGlutamate levelsExtracellular glutamate