title: Thalamic interictal epileptiform discharges in deep brain stimulated epilepsy patients.
abstract: The relationships between interictal epileptiform discharges (IEDs) in the anterior (ANT) and dorsomedial nuclei (DMNT) of the thalamus and electro-clinical parameters in pharmacoresistant focal epilepsy patients receiving intrathalamic electrodes for deep brain stimulation (DBS) were investigated. Thalamus-localized IEDs (LIEDs) and surface EEG (sEEG)-IEDs were evaluated in eight patients who underwent ANT-DBS. Occurrence and frequency of ANT- and DMNT-LIEDs and pre-operative sEEG-IEDs were examined with respect to seizure onset location and seizure outcome following ANT-DBS. LIEDs were identified in all eight patients, in the ANT, DMNT, or both. ANT-LIEDs were observed in all patients with an unequivocal temporal seizure onset zone. The ANT-LIED frequency correlated with pre-surgical sEEG-IED frequency (ρ = 0.76, p = 0.033) and predicted ANT-DBS responsiveness (T = -2.6; p = 0.0428). Of the five patients with bilateral sEEG-IEDs, all had ANT-LIEDs, but only one patient had DMNT-LIEDs. All patients with no or unilateral sEEG-IEDs had DMNT-LIEDs. Observation of LIEDS in the ANT and DMNT supports the hypothesis that these nuclei are involved in propagation of focal epileptic activity. Their correspondence with differing electro-clinical features suggests that these nuclei are functionally distinguishable nodes within the epileptic networks of individual patients.
authors.affiliation: Department of Neurology, Otto-von-Guericke University, Magdeburg, Germany. catherine.sweeney-reed@med.ovgu.de.
authors.forename: Catherine M
authors.initials: CM
authors.lastname: Sweeney-Reed
authors.affiliation: Department of Neurology, Otto-von-Guericke University, Magdeburg, Germany.
authors.forename: Harim
authors.initials: H
authors.lastname: Lee
authors.affiliation: Department of Neurosurgery, University Hospital Erlangen, Erlangen, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Rampp
authors.affiliation: Department of Neurology, Otto-von-Guericke University, Magdeburg, Germany.
authors.forename: Tino
authors.initials: T
authors.lastname: Zaehle
authors.affiliation: Department of Stereotactic Neurosurgery, Otto-von-Guericke University, Magdeburg, Germany.
authors.forename: Lars
authors.initials: L
authors.lastname: Buentjen
authors.affiliation: Department of Stereotactic Neurosurgery, Otto-von-Guericke University, Magdeburg, Germany.|Leibniz Institute for Neurobiology, Magdeburg, Germany.
authors.forename: Juergen
authors.initials: J
authors.lastname: Voges
authors.affiliation: Department of Neurology, Epilepsy-Center Berlin-Brandenburg, Charité-Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Holtkamp
authors.affiliation: Department of Neurology, Otto-von-Guericke University, Magdeburg, Germany.|Leibniz Institute for Neurobiology, Magdeburg, Germany.|German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany.
authors.forename: Hermann
authors.initials: H
authors.lastname: Hinrichs
authors.affiliation: Department of Neurology, Otto-von-Guericke University, Magdeburg, Germany.|Leibniz Institute for Neurobiology, Magdeburg, Germany.|German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany.
authors.forename: Hans-Jochen
authors.initials: HJ
authors.lastname: Heinze
authors.affiliation: Department of Neurology, Otto-von-Guericke University, Magdeburg, Germany. fc.schmitt@med.ovgu.de.
authors.forename: Friedhelm C
authors.initials: FC
authors.lastname: Schmitt
mesh_terms: D000368:Aged; D001931:Brain Mapping; D058256:Brain Waves; D046690:Deep Brain Stimulation / Q000379:methods*; D000069279:Drug Resistant Epilepsy / Q000000981:diagnostic imaging / Q000628:therapy*; D004566:Electrodes; D004569:Electroencephalography; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009862:Online Systems; D013788:Thalamus / Q000502:physiology*; D014057:Tomography, X-Ray Computed
keywords: Anterior nucleus of the thalamus; Deep brain stimulation; Dorsomedial nucleus of the thalamus; Interictal epileptiform discharges; Refractory epilepsy