title: The predictive value of low-field strength   magnetic resonance imaging for intraoperative   residual tumor detection.   Clinical article.
abstract: OBJECTIVE
  Neurosurgeons have been utilizing intraoperative MR (iMR) imaging to evaluate the extent of tumor resection since the 1990s. A low-field strength (0.12 T) MR imaging unit (PoleStar N20, Medtronic) is a practical and relatively inexpensive iMR imaging system that has found increased use in neurosurgery. The gold standard for post operative detection of residual tumor has been high-strength MR imaging performed within 48 hours of resection.The object of this study was to determine the predictive concordance of low-strength iMR imaging with standard high-strength MR imaging for detection of residual tumor.
  
  
  METHODS
  The authors retrospectively evaluated the MR images from 74 intracranial tumor resections, comparing the intraoperative images obtained using a 0.12-T iMR imaging unit to the immediate postoperative images obtained using a standard 1.5-T MR imaging unit within 48 hours after surgery.
  
  
  RESULTS
  The sensitivity of low-field MR imaging for detection of residual tumor was 0.74 (95% CI 0.58-0.86),and its specificity was 0.97 (95% CI 0.83-1). When only glial tumors (42 of the 74 lesions) were analyzed, the sensitivity was 0.82 (95% CI 0.59-0.94) and the specificity was 0.95 (95% CI 0.73-1).
  
  
  CONCLUSIONS
  These data could assist the neurosurgeon who has to decide intraoperatively whether the observed iMR images show residual tumor or not.
authors.affiliation: Dardinger Neuro-oncology Center, Department of Neurological Surgery, The Ohio State University Medical Center, Columbus, Ohio 43210, USA.
authors.forename: Robert A
authors.initials: RA
authors.lastname: Hirschl
authors.forename: Jeff
authors.initials: J
authors.lastname: Wilson
authors.forename: Brandon
authors.initials: B
authors.lastname: Miller
authors.forename: Sergio
authors.initials: S
authors.lastname: Bergese
authors.forename: E  Antonio
authors.initials: E
authors.lastname: Chiocca
mesh_terms: D001932:Brain Neoplasms / Q000175:diagnosis* / Q000601:surgery; D006801:Humans; D007432:Intraoperative Period; D008279:Magnetic Resonance Imaging / Q000379:methods*; D018365:Neoplasm, Residual / Q000175:diagnosis*; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012680:Sensitivity and Specificity