title: Awake mapping for resection of cavernous angioma and surrounding gliosis in the left dominant hemisphere: surgical technique and functional results: clinical article.
abstract: OBJECTIVE
  Maximal resection of symptomatic cavernous angioma (CA), including its surrounding gliosis if possible, has been recommended to minimize the risk of seizures or (re)bleeding. However, despite recent neurosurgical advances, such extensive CA removal is still a challenge in eloquent areas. The authors report a consecutive series of patients who underwent awake surgery for CA within the left dominant hemisphere in which intraoperative cortical-subcortical electrical stimulation was used.
  
  
  METHODS
  Nine patients harboring a CA that was revealed by seizures in 6 cases and bleeding in 3 cases underwent resection. All CAs were located in the left dominant hemisphere: 3 temporal, 2 insular, 2 parietal, and 2 in the parietotemporal region. Awake mapping was performed in all cases by using intraoperative cortical-subcortical electrical stimulation and ultrasonography (except in 1 insular CA in which a neuronavigation system was used).
  
  
  RESULTS
  Total removal of the CA was achieved in all patients, with identification and preservation of language and sensory-motor structures. In addition, the pericavernomatous gliosis was removed in 7 cases, according to the functional boundaries provided by intraoperative subcortical stimulation. In 2 cases, subcortical mapping revealed eloquent areas within the surrounding gliosis, which was voluntarily avoided. There was no postsurgical permanent deficit, no rebleeding, and no epilepsy in 7 cases (2 patients had rare seizures in the 1st year or two after surgery, and then complete arrest), with a mean follow-up of 28.5 months (range 3-64 months).
  
  
  CONCLUSIONS
  These results suggest that intraoperative cortical-subcortical stimulation in awake patients represents a valuable adjunct to image-guided surgery with the aim of selecting the safer surgical approach for CAs involving eloquent areas. Moreover, such online mapping can be helpful when removing the pericavernomatous gliosis while preserving functional structures, which can persist within the hemosiderin rim. Thus, the authors propose that awake surgery be routinely considered, both to optimize the resection and to improve the quality of life through seizure control and avoidance of (re)bleeding for CAs located in the left dominant hemisphere.
authors.affiliation: Department of Neurosurgery, Nara Medical University, Kashihara, Nara, Japan.
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Matsuda
authors.forename: Alejandro Fernández
authors.initials: AF
authors.lastname: Coello
authors.forename: Alessandro
authors.initials: A
authors.lastname: De Benedictis
authors.forename: Matteo
authors.initials: M
authors.lastname: Martinoni
authors.forename: Hugues
authors.initials: H
authors.lastname: Duffau
mesh_terms: D000293:Adolescent; D000328:Adult; D001931:Brain Mapping / Q000379:methods*; D001932:Brain Neoplasms / Q000150:complications / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D002540:Cerebral Cortex / Q000473:pathology* / Q000503:physiopathology / Q000601:surgery*; D046690:Deep Brain Stimulation; D004292:Dominance, Cerebral; D005260:Female; D005625:Frontal Lobe / Q000473:pathology / Q000503:physiopathology / Q000601:surgery; D007839:Functional Laterality; D005911:Gliosis; D006392:Hemangioma, Cavernous / Q000150:complications / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods*; D009413:Nerve Fibers, Myelinated / Q000473:pathology; D038361:Neuronavigation / Q000379:methods*; D009483:Neuropsychological Tests; D019635:Neurosurgical Procedures / Q000379:methods*; D012189:Retrospective Studies; D012640:Seizures / Q000209:etiology / Q000517:prevention & control*; D016896:Treatment Outcome; D014851:Wakefulness