title: Awake mapping optimizes the extent of resection for low-grade gliomas in eloquent areas.
abstract: BACKGROUND
  Awake craniotomy with intraoperative electrical mapping is a reliable method to minimize the risk of permanent deficit during surgery for low-grade glioma located within eloquent areas classically considered inoperable. However, it could be argued that preservation of functional sites might lead to a lesser degree of tumor removal. To the best of our knowledge, the extent of resection has never been directly compared between traditional and awake procedures.
  
  
  OBJECTIVE
  We report for the first time a series of patients who underwent 2 consecutive surgeries without and with awake mapping.
  
  
  METHODS
  Nine patients underwent surgery for a low-grade glioma in functional sites under general anesthesia in other institutions. The resection was subtotal in 3 cases and partial in 6 cases. There was a postoperative worsening in 3 cases. We performed a second surgery in the awake condition with intraoperative electrostimulation. The resection was performed according to functional boundaries at both the cortical and subcortical levels.
  
  
  RESULTS
  Postoperative magnetic resonance imaging showed that the resection was complete in 5 cases and subtotal in 4 cases (no partial removal) and that it was improved in all cases compared with the first surgery (P = .04). There was no permanent neurological worsening. Three patients improved compared with the presurgical status. All patients returned to normal professional and social lives.
  
  
  CONCLUSIONS
  Our results demonstrate that awake surgery, known to preserve the quality of life in patients with low-grade glioma, is also able to significantly improve the extent of resection for lesions located in functional regions.
authors.affiliation: Department of Surgical Sciences, Neurosurgical Unit, University of Insubria, Varese, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: De Benedictis
authors.forename: Sylvie
authors.initials: S
authors.lastname: Moritz-Gasser
authors.forename: Hugues
authors.initials: H
authors.lastname: Duffau
mesh_terms: D000328:Adult; D000368:Aged; D001931:Brain Mapping / Q000379:methods*; D001932:Brain Neoplasms / Q000175:diagnosis / Q000473:pathology* / Q000601:surgery*; D003399:Craniotomy / Q000009:adverse effects / Q000379:methods; D004558:Electric Stimulation / Q000379:methods; D004568:Electrodiagnosis / Q000379:methods*; D005260:Female; D005910:Glioma / Q000175:diagnosis / Q000473:pathology* / Q000601:surgery*; D006801:Humans; D007806:Language Disorders / Q000517:prevention & control; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods*; D019635:Neurosurgical Procedures / Q000009:adverse effects / Q000379:methods*; D011183:Postoperative Complications / Q000175:diagnosis / Q000209:etiology / Q000517:prevention & control; D011788:Quality of Life; D016896:Treatment Outcome; D014851:Wakefulness; D055815:Young Adult