title: Clinical MRI interpretation for outcome prediction in cardiac arrest.
abstract: BACKGROUND
  In clinical practice, magnetic resonance imaging (MRI) is commonly used to assess the severity of a cardiac arrest patient's cerebral injury, utilizing treating neurologists' imaging interpretation. We sought to determine whether clinical interpretation of diffusion-weighted imaging (DWI) helps to determine poor outcome in comatose cardiac arrest patients.
  
  
  METHODS
  We analyzed 80 consecutive MRIs from patients in coma following cardiac arrest. Each study was graded as "normal" or "abnormal restricted diffusion" in pre-specified brain regions by two blinded stroke neurologists. Poor outcome was defined as a modified Rankin Scale (mRS) score >4 at 3 months. Formal interpretations of neuroimaging by non-blinded neuroradiologists were compared with the blinded reviews by the stroke neurologists.
  
  
  RESULTS
  DWI abnormalities were highly sensitive (98.5 %) but only modestly specific (46.2 %) for predicting poor neurological outcome. Inter-observer reliability was moderate (kappa = 0.49 ± 0.32), with 91 % agreement between study observers, and no significant differences in study observers' interpretations (p = 0.125). There were, however, significant differences between the study observers and the clinical neuroradiologists in identifying studies showing evidence of global hypoxic-ischemic injury (p = 0.001).
  
  
  CONCLUSIONS
  The qualitative evaluation of imaging abnormalities by stroke physicians in comatose cardiac arrest patients is a highly sensitive method of predicting poor outcome, but with limited specificity.
authors.affiliation: Department of Neurology, Yale University School of Medicine, LLCI 912, 15 York Street, New Haven, CT 06520, USA. david.greer@yale.edu
authors.forename: David
authors.initials: D
authors.lastname: Greer
authors.forename: Patricia
authors.initials: P
authors.lastname: Scripko
authors.forename: James
authors.initials: J
authors.lastname: Bartscher
authors.forename: John
authors.initials: J
authors.lastname: Sims
authors.forename: Erica
authors.initials: E
authors.lastname: Camargo
authors.forename: Aneesh
authors.initials: A
authors.lastname: Singhal
authors.forename: Michael
authors.initials: M
authors.lastname: Parides
authors.forename: Karen
authors.initials: K
authors.lastname: Furie
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001921:Brain / Q000473:pathology*; D015331:Cohort Studies; D003128:Coma / Q000209:etiology*; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006323:Heart Arrest / Q000150:complications*; D006801:Humans; D020925:Hypoxia-Ischemia, Brain / Q000175:diagnosis* / Q000209:etiology / Q000473:pathology; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011379:Prognosis; D012680:Sensitivity and Specificity