title: NIRS-measured oxy- and deoxyhemoglobin changes associated with EEG spike-and-wave discharges in children.
abstract: OBJECTIVE
  Absence epilepsy is characterized by 3-Hz generalized spike-and-wave discharges (GSWD) on the electroencephalogram, associated with behavioral arrest. It may be severe, and even in childhood benign absence epilepsy cognitive delay is frequent, yet the metabolic/hemodynamic aspects of this kind of epilepsy have not been established. We aimed to determine if the GSWD were related to hemodynamic changes by using a new technique with high temporal resolution: near infrared spectroscopy (NIRS).
  
  
  METHODS
  NIRS is gaining acceptance as a technique particularly suitable for routine follow-up in children, using the specific absorption properties of living tissues in the near infrared range to measure changes in the concentrations of oxy-, deoxy- and total hemoglobin (HbO(2), HHb, and HbT, respectively). We performed simultaneous electroencephalography (EEG) and left frontal NIRS recordings in six children with GSWD. We also tested if the discharges were related to changes in cardiac or respiratory rates.
  
  
  RESULTS
  GSWD were associated in the frontal area with an oxygenation (beginning 10 s before the GSWD) followed by strong deoxygenation, then oxygenation again with [HbT] increase, and a return to baseline. We did not identify any relationship between the onset of the GSWD and heart or respiratory rates.
  
  
  CONCLUSIONS
  Our results partially differ from previous studies on GSWD hemodynamic aspects (many of which described a simple deactivation), probably due to differences in temporal resolution and data processing. Simultaneous acquisition of EEG and NIRS can optimize the use of both techniques and help shed light on the mechanisms underlying spike-and-wave discharges.
authors.affiliation: GRAMFC, Faculté de Médecine, UPJV, Amiens, France. nadege.roche@u-picardie.fr
authors.forename: Nadège
authors.initials: N
authors.lastname: Roche-Labarbe
authors.forename: Boubker
authors.initials: B
authors.lastname: Zaaimi
authors.forename: Patrick
authors.initials: P
authors.lastname: Berquin
authors.forename: Astrid
authors.initials: A
authors.lastname: Nehlig
authors.forename: Reinhard
authors.initials: R
authors.lastname: Grebe
authors.forename: Fabrice
authors.initials: F
authors.lastname: Wallois
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D004569:Electroencephalography; D004832:Epilepsy, Absence / Q000175:diagnosis / Q000378:metabolism* / Q000503:physiopathology*; D004829:Epilepsy, Generalized / Q000175:diagnosis / Q000378:metabolism* / Q000503:physiopathology*; D005260:Female; D005500:Follow-Up Studies; D006454:Hemoglobins / Q000378:metabolism*; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging; D008297:Male; D010108:Oxyhemoglobins / Q000378:metabolism*; D019265:Spectroscopy, Near-Infrared / Q000379:methods*
chemical_list: D006454:Hemoglobins; D010108:Oxyhemoglobins; C100003:deoxyhemoglobin