title: Impact of intraoperative high-field magnetic resonance imaging guidance on glioma surgery: a prospective volumetric analysis.
abstract: OBJECTIVE
  To determine the impact of intraoperative magnetic resonance imaging (iMRI) on the decision to proceed with additional glioma resection during surgery and to maximize extent of resection (EOR).
  
  
  METHODS
  Patients who underwent craniotomy for glioma resection with high-field iMRI guidance were prospectively evaluated between September 2006 and August 2007. Volumetric analysis and EOR were assessed with iMRI, using postcontrast T1-weighted images for tumors showing contrast enhancement and T2-weighted images for nonenhancing tumors.
  
  
  RESULTS
  Forty-six patients underwent resection using iMRI guidance, with iMRI being used to evaluate the EOR in 44 patients and for reregistration in 2 patients. Surgery was terminated after iMRI in 23 patients (52%) because gross total resection was achieved or because of residual tumor infiltration in an eloquent brain region. Twenty-one patients (47%) underwent additional resection of residual tumor after iMRI. For enhancing gliomas, the median EOR increased significantly from 84% (range, 59%-97%) to 99% (range, 85%-100%) with additional tumor removal after iMRI (P < 0.001). For nonenhancing gliomas, the median EOR increased (from 63% to 80%) with additional tumor removal after iMRI, but not significantly, owing to the small sample size (7 patients). Overall, the EOR increased from 76% (range, 35%-97%) to 96% (range, 48%-100%) (P < 0.001). Gross total resection was achieved after additional tumor removal after iMRI in 15 of 21 patients (71%). Overall, 29 patients (65%) experienced gross total resection, and in 15 (52%), this was achieved with the contribution of iMRI.
  
  
  CONCLUSIONS
  High-field iMRI is a safe and reliable technique, and its use optimizes the extent of glioma resection.
authors.affiliation: Department of Neurosurgery, The University of Texas, MD Anderson Cancer Center, Houston, Texas, USA.
authors.forename: Mustafa Aziz
authors.initials: MA
authors.lastname: Hatiboglu
authors.forename: Jeffrey S
authors.initials: JS
authors.lastname: Weinberg
authors.forename: Dima
authors.initials: D
authors.lastname: Suki
authors.forename: Ganesh
authors.initials: G
authors.lastname: Rao
authors.forename: Sujit S
authors.initials: SS
authors.lastname: Prabhu
authors.forename: Komal
authors.initials: K
authors.lastname: Shah
authors.forename: Ed
authors.initials: E
authors.lastname: Jackson
authors.forename: Raymond
authors.initials: R
authors.lastname: Sawaya
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001932:Brain Neoplasms / Q000473:pathology* / Q000601:surgery*; D002648:Child; D002675:Child, Preschool; D003399:Craniotomy / Q000379:methods*; D005260:Female; D005910:Glioma / Q000473:pathology* / Q000601:surgery*; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods; D011183:Postoperative Complications; D011446:Prospective Studies; D012189:Retrospective Studies; D055815:Young Adult