title: Impact of psychogenic nonepileptic seizures on epilepsy presurgical investigation and surgical outcomes.
abstract: BACKGROUND
  We sought to determine the percentage of patients undergoing presurgical assessment that had both psychogenic nonepileptic seizures (PNESs) and epileptic seizures (ESs) captured within our telemetry unit and how this affected progression to surgery and describe eventual outcomes in patients with a history of mixed PNESs/ESs who underwent surgery.
  
  
  METHODS
  To determine what happened to patients who had PNESs recorded during a presurgical workup, we reviewed the records of 725 patients admitted to our telemetry unit for presurgical assessment between 2007 and 2013 and identified those with PNESs and ESs recorded. To determine outcomes postsurgery in operated patients who had mixed PNESs/ESs, we also reviewed the records of 519 patients who had had epilepsy surgery between 1999 and 2012 and identified those within this group who also had PNESs prior to surgery.
  
  
  RESULTS
  Nineteen of the 725 patients had PNESs captured during their presurgical telemetry along with ESs captured on either this or a previous study. Four of these patients were ultimately offered surgery. Nine of the 519 patients with a history of PNESs underwent epilepsy surgery. At 1 to 5years of follow-up (mean: 4.1years) of those nine patients, five were still having ESs and three patients had worsening or new-onset PNESs. At the last follow-up, four had had a worthwhile improvement.
  
  
  CONCLUSIONS
  This study suggests that recent outcomes for people with mixed PNESs/ESs are not as promising as previously described and that PNESs should remain a relative contraindication for surgery.
authors.affiliation: Sir Jules Thorn Telemetry Unit, National Hospital for Neurology and Neurosurgery, London WC1N 3BG, UK. Electronic address: Kimberley.Whitehead@uclh.nhs.uk.
authors.forename: Kimberley
authors.initials: K
authors.lastname: Whitehead
authors.affiliation: Department of Clinical Neurophysiology, National Hospital for Neurology and Neurosurgery, London WC1N 3BG, UK. Electronic address: Suzanne.O'Sullivan@uclh.nhs.uk.
authors.forename: Suzanne
authors.initials: S
authors.lastname: O'Sullivan
authors.affiliation: Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, London WC1N 3BG, UK. Electronic address: m.walker@ion.ucl.ac.uk.
authors.forename: Matthew
authors.initials: M
authors.lastname: Walker
mesh_terms: D015897:Comorbidity; D005500:Follow-Up Studies; D006801:Humans; D011183:Postoperative Complications / Q000453:epidemiology; D011300:Preoperative Care; D012640:Seizures / Q000453:epidemiology / Q000209:etiology / Q000601:surgery*; D013001:Somatoform Disorders / Q000453:epidemiology / Q000601:surgery*; D017211:Treatment Failure; D016896:Treatment Outcome
keywords: Epilepsy surgery; Nonepileptic attack disorder; Outcomes; Psychogenic nonepileptic seizures