title: Deep brain stimulation of the centromedian thalamic nucleus for the treatment of generalized and frontal epilepsies.
abstract: OBJECTIVE
  Deep brain stimulation (DBS) of the thalamus is an emerging surgical option for people with medically refractory epilepsy that is not suitable for resective surgery, or in whom surgery has failed. Our main aim was to evaluate the efficacy of bilateral centromedian thalamic nucleus (CMN) DBS for seizure control in generalized epilepsy and frontal lobe epilepsy with a two-center, single-blind, controlled trial.
  
  
  METHODS
  Participants were adults with refractory generalized or frontal lobe epilepsy. Seizure diaries were kept by patients/carers prospectively from enrollment. The baseline preimplantation period was followed by a control period consisting of a blind stimulation-OFF phase of at least 3 months, a 3-month blind stimulation-ON phase, and a 6-month unblinded stimulation-ON phase. The control period was followed by an unblinded long-term extension phase with stimulation-ON in those patients in whom stimulation was thought to be effective.
  
  
  RESULTS
  Eleven patients were recruited at King's College Hospital (London, United Kingdom United Kingdom) and at University Hospital La Princesa (Madrid, Spain). Among the five patients with frontal lobe epilepsy, only one patient had >50% improvement in seizure frequency during the blind period. In the long-term extension phase, two patients with frontal lobe epilepsy had >50% improvement in seizure frequency. All six patients with generalized epilepsy had >50% improvement in seizure frequency during the blind period. In the long-term extension phase, five of the six patients showed >50% improvement in the frequency of major seizures (one became seizure free, one had >99% improvement, and three had 60-95% reduction in seizure frequency). Among patients with generalized epilepsy, the DBS implantation itself appears to be effective, as two patients remained seizure free during 12 and 50 months with DBS OFF, and the remaining four had 50-91% improvement in the initial 3 months with DBS OFF.
  
  
  CONCLUSIONS
  DBS implantation and stimulation of the CMN appears to be a safe and efficacious treatment, particularly in patients with refractory generalized epilepsy. CMN stimulation was not as effective in frontal lobe epilepsy, which requires further studies. DBS of the CMN should be considered as a treatment option, particularly in patients with refractory generalized epilepsy syndromes.
authors.affiliation: Department of Clinical Neurophysiology, King's College Hospital, London, United Kingdom; Department of Clinical Neuroscience, Institute of Psychiatry, King's College London, London, United Kingdom.
authors.forename: Antonio
authors.initials: A
authors.lastname: Valentín
authors.forename: Eduardo
authors.initials: E
authors.lastname: García Navarrete
authors.forename: Ramesh
authors.initials: R
authors.lastname: Chelvarajah
authors.forename: Cristina
authors.initials: C
authors.lastname: Torres
authors.forename: Marta
authors.initials: M
authors.lastname: Navas
authors.forename: Lelia
authors.initials: L
authors.lastname: Vico
authors.forename: Nerea
authors.initials: N
authors.lastname: Torres
authors.forename: Jesus
authors.initials: J
authors.lastname: Pastor
authors.forename: Richard
authors.initials: R
authors.lastname: Selway
authors.forename: Rafael G
authors.initials: RG
authors.lastname: Sola
authors.forename: Gonzalo
authors.initials: G
authors.lastname: Alarcon
mesh_terms: D000293:Adolescent; D000328:Adult; D046690:Deep Brain Stimulation / Q000379:methods*; D017034:Epilepsy, Frontal Lobe / Q000503:physiopathology / Q000628:therapy*; D004829:Epilepsy, Generalized / Q000503:physiopathology / Q000628:therapy*; D005260:Female; D006801:Humans; D020646:Intralaminar Thalamic Nuclei / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D016037:Single-Blind Method; D016896:Treatment Outcome; D055815:Young Adult
keywords: Centromedian; Deep brain stimulation; Epilepsy; Epilepsy surgery; Seizure; Thalamus