title: Resection of olfactory groove meningioma - a review of complications and prognostic factors.
abstract: BACKGROUND
  High complication rates have been cited following olfactory groove meningioma (OGM) resection but data are lacking on attendant risk factors. We aimed to review the complications following OGM resection and identify prognostic factors.
  
  
  METHODS
  A retrospective review was performed on 34 consecutive patients who underwent primary OGM resection at a single London institution between March 2008 and February 2013. Collected data included patient comorbidities, pre-operative corticosteroid use, tumour characteristics, imaging features, operative details, extent of resection, histology, use of elective post-operative ventilation, complications, recurrence and mortality.
  
  
  RESULTS
  Complication rate was 39%. 58% of complications required intensive care or re-operation. Higher complication rates occurred with OGM > 40 mm diameter versus ≤ 40 mm (53 vs. 28%; p = 0.16); OGM with versus without severe perilesional oedema (59 vs. 19%; p = 0.26), more evident when corrected for tumour size; and patients receiving 1-2 days versus 3-5 days of pre-operative dexamethasone (75 vs. 19%; p = 0.016). Patients who were electively ventilated post-operatively versus those who were not had higher risk tumours but a lower complication rate (17 vs. 44%; p = 0.36) and a higher proportion making a good recovery (83 vs. 55%; p = 0.20). Complete versus incomplete resection had a higher complication rate (50 vs. 23%; p = 0.16) but no recurrence (0 vs. 25%; p = 0.07).
  
  
  CONCLUSIONS
  Risk of morbidity with OGM resection is high. Higher complication risk is associated with larger tumours and greater perilesional oedema. Pre-operative dexamethasone for 3-5 days versus shorter periods may reduce the risk of complications. We describe a characteristic pattern of perilesional oedema termed 'sabre-tooth' sign, whose presence is associated with a higher complication rate and may represent an important radiological prognostic sign. Elective post-operative ventilation for patients with high-risk tumours may reduce the risk of complications.
authors.affiliation: a Department of Neurosurgery , King's College Hospital , London , UK.
authors.forename: Soumya
authors.initials: S
authors.lastname: Mukherjee
authors.affiliation: a Department of Neurosurgery , King's College Hospital , London , UK.
authors.forename: Bhaskar
authors.initials: B
authors.lastname: Thakur
authors.affiliation: a Department of Neurosurgery , King's College Hospital , London , UK.
authors.forename: Robert
authors.initials: R
authors.lastname: Corns
authors.affiliation: a Department of Neurosurgery , King's College Hospital , London , UK.
authors.forename: Steve
authors.initials: S
authors.lastname: Connor
authors.affiliation: a Department of Neurosurgery , King's College Hospital , London , UK.
authors.forename: Ranjeev
authors.initials: R
authors.lastname: Bhangoo
authors.affiliation: a Department of Neurosurgery , King's College Hospital , London , UK.
authors.forename: Keyoumars
authors.initials: K
authors.lastname: Ashkan
authors.affiliation: a Department of Neurosurgery , King's College Hospital , London , UK.
authors.forename: Richard
authors.initials: R
authors.lastname: Gullan
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use; D001929:Brain Edema / Q000453:epidemiology / Q000209:etiology; D002648:Child; D002675:Child, Preschool; D003422:Critical Care / Q000706:statistics & numerical data; D003907:Dexamethasone / Q000627:therapeutic use; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008579:Meningioma / Q000473:pathology / Q000601:surgery*; D008875:Middle Aged; D018365:Neoplasm, Residual / Q000473:pathology; D019635:Neurosurgical Procedures / Q000009:adverse effects* / Q000379:methods*; D011183:Postoperative Complications / Q000188:drug therapy / Q000453:epidemiology; D011379:Prognosis; D012086:Reoperation / Q000706:statistics & numerical data; D012189:Retrospective Studies; D019292:Skull Base Neoplasms / Q000473:pathology / Q000601:surgery*; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D000893:Anti-Inflammatory Agents; D003907:Dexamethasone
keywords: complications; elective ventilation; olfactory groove meningioma; perilesional oedema; resection