title: Morbidity associated with the use of intracranial electrodes for epilepsy surgery.
abstract: BACKGROUND
  Invasive monitoring for the investigation of medically intractable epilepsy may be associated with undesirable morbidity. We performed a review of our recent experience to determine the incidence of major complications.
  
  
  METHODS
  We reviewed the clinical records of all patients who underwent invasive EEG monitoring at our institution between 2000 and 2004.
  
  
  RESULTS
  One-hundred and sixteen patients (57 males, 59 females) with a mean age of 32 years of age underwent intracranial placement of electrodes for epilepsy surgery investigation. Subdural strips were placed in 115 patients with a mean of eight strips per patient. Subdural grids were inserted in 11 patients and depth electrodes in five. Fourteen of the 15 patients with grids or depth electrodes also had strips. Coverage was unilateral in 37 patients and bilateral in 79 patients. Electrodes were placed over the frontal lobe in 78 cases, temporal in 93, parietal in 24, and occipital in 27 patients. The average duration of investigation was 12.3 days (range 3-29). The evaluation led to the performance of a surgical resection in 85 patients (74%). Complications were seen in four patients with subdural strips (3%), and in two patients with grids (13%), characterized by clinical infection, intracranial hemorrhage, aseptic meningitis, transient neurological deficits, and status epilepticus. Mortality was nil.
  
  
  CONCLUSIONS
  In comparison with previously published literature on the topic, the major complication rate in this group of patients appears to be low.
authors.affiliation: Epilepsy Programme, Department of Clinical Neurological Sciences, London Health Sciences Centre, University of Western Ontario, London, ON, Canada.
authors.forename: Jorge G
authors.initials: JG
authors.lastname: Burneo
authors.forename: David A
authors.initials: DA
authors.lastname: Steven
authors.forename: Richard S
authors.initials: RS
authors.lastname: McLachlan
authors.forename: Andrew G
authors.initials: AG
authors.lastname: Parrent
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001921:Brain / Q000503:physiopathology / Q000601:surgery; D002648:Child; D004567:Electrodes, Implanted / Q000009:adverse effects; D004569:Electroencephalography / Q000009:adverse effects*; D004827:Epilepsy / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000009:adverse effects*; D019635:Neurosurgical Procedures / Q000009:adverse effects* / Q000295:instrumentation; D011183:Postoperative Complications / Q000209:etiology* / Q000517:prevention & control; D019106:Postoperative Hemorrhage / Q000209:etiology / Q000517:prevention & control; D013226:Status Epilepticus / Q000209:etiology / Q000517:prevention & control; D013355:Subdural Space / Q000601:surgery; D013530:Surgical Wound Infection / Q000209:etiology / Q000517:prevention & control