title: Diagnostic yield of short-term video-EEG monitoring for epilepsy and PNESs: a European assessment.
abstract: BACKGROUND
  Although long-term video-EEG monitoring (LVEM) is routinely used to investigate paroxysmal events, short-term video-EEG monitoring (SVEM) lasting <24 h is increasingly recognized as a cost-effective tool. Since, however, relatively few studies addressed the yield of SVEM among different diagnostic groups, we undertook the present study to investigate this aspect.
  
  
  METHODS
  We retrospectively analyzed 226 consecutive SVEM recordings over 6 years. All patients were referred because routine EEGs were inconclusive. Patients were classified into 3 suspected diagnostic groups: (1) group with epileptic seizures, (2) group with psychogenic nonepileptic seizures (PNESs), and (3) group with other or undetermined diagnoses. We assessed recording lengths, interictal epileptiform discharges, epileptic seizures, PNESs, and the definitive diagnoses obtained after SVEM.
  
  
  RESULTS
  The mean age was 34 (±18.7) years, and the median recording length was 18.6 h. Among the 226 patients, 127 referred for suspected epilepsy - 73 had a diagnosis of epilepsy, none had a diagnosis of PNESs, and 54 had other or undetermined diagnoses post-SVEM. Of the 24 patients with pre-SVEM suspected PNESs, 1 had epilepsy, 12 had PNESs, and 11 had other or undetermined diagnoses. Of the 75 patients with other diagnoses pre-SVEM, 17 had epilepsy, 11 had PNESs, and 47 had other or undetermined diagnoses. After SVEM, 15 patients had definite diagnoses other than epilepsy or PNESs, while in 96 patients, diagnosis remained unclear. Overall, a definitive diagnosis could be reached in 129/226 (57%) patients.
  
  
  CONCLUSIONS
  This study demonstrates that in nearly 3/5 patients without a definitive diagnosis after routine EEG, SVEM allowed us to reach a diagnosis. This procedure should be encouraged in this setting, given its time-effectiveness compared with LVEM.
authors.affiliation: Department of Clinical Neurosciences, Lausanne University Hospital and University of Lausanne, Switzerland.
authors.forename: Luca
authors.initials: L
authors.lastname: Bettini
authors.affiliation: Department of Clinical Neurosciences, Lausanne University Hospital and University of Lausanne, Switzerland.
authors.forename: Alexandre
authors.initials: A
authors.lastname: Croquelois
authors.affiliation: Department of Clinical Neurosciences, Lausanne University Hospital and University of Lausanne, Switzerland; Institution de Lavigny, Switzerland.
authors.forename: Malin
authors.initials: M
authors.lastname: Maeder-Ingvar
authors.affiliation: Department of Clinical Neurosciences, Lausanne University Hospital and University of Lausanne, Switzerland. Electronic address: andrea.rossetti@chuv.ch.
authors.forename: Andrea O
authors.initials: AO
authors.lastname: Rossetti
mesh_terms: D000293:Adolescent; D000328:Adult; D003943:Diagnostic Techniques, Neurological / Q000592:standards*; D004569:Electroencephalography / Q000379:methods*; D004827:Epilepsy / Q000175:diagnosis*; D005060:Europe; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011602:Psychophysiologic Disorders / Q000175:diagnosis*; D012640:Seizures / Q000175:diagnosis*; D013997:Time Factors; D014741:Video Recording; D055815:Young Adult
keywords: Epilepsy; Parasomnia; Psychogenic nonepileptic seizures (PNESs); Seizures