title: Complications of invasive video-EEG monitoring with subdural grid electrodes.
abstract: OBJECTIVE
  To evaluate the risk factors, type, and frequency of complications during video-EEG monitoring with subdural grid electrodes.
  
  
  METHODS
  The authors retrospectively reviewed the records of all patients who underwent invasive monitoring with subdural grid electrodes (n = 198 monitoring sessions on 187 patients; median age: 24 years; range: 1 to 50 years) at the Cleveland Clinic Foundation from 1980 to 1997.
  
  
  RESULTS
  From 1980 to 1997, the complication rate decreased (p = 0.003). In the last 5 years, 19/99 patients (19%) had complications, including two patients (2%) with permanent sequelae. In the last 3 years, the complication rate was 13.5% (n = 5/37) without permanent deficits. Overall, complications occurred during 52 monitoring sessions (26.3%): infection (n = 24; 12.1%), transient neurologic deficit (n = 22; 11.1%), epidural hematoma (n = 5; 2.5%), increased intracranial pressure (n = 5; 2.5%), and infarction (n = 3; 1.5%). One patient (0.5%) died during grid insertion. Complication occurrence was associated with greater number of grids/electrodes (p = 0.021/p = 0.052; especially >60 electrodes), longer duration of monitoring (p = 0.004; especially >10 days), older age of the patient (p = 0.005), left-sided grid insertion (p = 0.01), and burr holes in addition to the craniotomy (p = 0.022). No association with complications was found for number of seizures, IQ, anticonvulsants, or grid localization.
  
  
  CONCLUSIONS
  Invasive monitoring with grid electrodes was associated with significant complications. Most of them were transient. Increased complication rates were related to left-sided grid insertion and longer monitoring with a greater number of electrodes (especially more than 60 electrodes). Improvements in grid technology, surgical technique, and postoperative care resulted in significant reductions in the complication rate.
authors.affiliation: Department of Neurology, University of Marburg, Germany. mer@mailer.uni-marburg.de
authors.forename: H M
authors.initials: HM
authors.lastname: Hamer
authors.forename: H H
authors.initials: HH
authors.lastname: Morris
authors.forename: E J
authors.initials: EJ
authors.lastname: Mascha
authors.forename: M T
authors.initials: MT
authors.lastname: Karafa
authors.forename: W E
authors.initials: WE
authors.lastname: Bingaman
authors.forename: M D
authors.initials: MD
authors.lastname: Bej
authors.forename: R C
authors.initials: RC
authors.lastname: Burgess
authors.forename: D S
authors.initials: DS
authors.lastname: Dinner
authors.forename: N R
authors.initials: NR
authors.lastname: Foldvary
authors.forename: J F
authors.initials: JF
authors.lastname: Hahn
authors.forename: P
authors.initials: P
authors.lastname: Kotagal
authors.forename: I
authors.initials: I
authors.lastname: Najm
authors.forename: E
authors.initials: E
authors.lastname: Wyllie
authors.forename: H O
authors.initials: HO
authors.lastname: Lüders
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D001424:Bacterial Infections / Q000209:etiology; D002493:Central Nervous System Diseases / Q000209:etiology; D002648:Child; D002675:Child, Preschool; D004567:Electrodes, Implanted; D004569:Electroencephalography / Q000009:adverse effects* / Q000295:instrumentation / Q000379:methods; D005260:Female; D006470:Hemorrhage / Q000209:etiology; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000009:adverse effects* / Q000295:instrumentation / Q000379:methods; D012189:Retrospective Studies; D012307:Risk Factors; D014741:Video Recording