title: The diagnostic accuracy of non-echo-planar diffusion-weighted imaging in the detection of residual and/or recurrent cholesteatoma of the temporal bone.
abstract: OBJECTIVE
  Non-EPI DWI is a promising alternative to second-look surgery for the detection of residual and/or recurrent cholesteatoma. We evaluated the diagnostic accuracy, expressed as a positive predictive value, of MR imaging for the detection of residual and/or recurrent cholesteatoma in our hospital.
  
  
  METHODS
  Fifty-six MR imaging studies were performed from 2005 to 2010 in patients having previously undergone surgery for cholesteatoma. Pre- and postgadolinium T1-weighted, T2-weighted, and non-EPI DWI sequences were performed and correlated with clinical and intraoperative findings. Twenty-seven patients underwent second-look surgery; 7 were under close clinical follow-up. Twenty-two patients without evidence of cholesteatoma were under regular follow-up (range, 14-44 months).
  
  
  RESULTS
  Non-EPI DWI sequences showed increased DW signal intensity in 36 patients. Of those, 27 had second-look surgery, confirming cholesteatoma in 25 patients; in 1 patient, an empyema was diagnosed, and in the other patient, no cholesteatoma was found at surgery. In 2 patients who had not undergone surgery, increased DW signal intensity was accompanied by hyperintense signal intensity on T1-weighted images, consistent with transplanted fat in the postoperative cavity. The positive predictive value for detection of cholesteatoma was 93% (25/27).
  
  
  CONCLUSIONS
  Residual and/or recurrent cholesteatomas after primary cholesteatoma surgery can be accurately detected by increased DW signal intensity on non-EPI DWI. However, DWI without conventional sequences increased the risk of misdiagnosis in our patient setting because transplanted fat within the postoperative cavity may show increased DW signal intensity.
authors.affiliation: Department of Radiology, Maastricht University Medical Centre, Maastricht, the Netherlands. m.dremmen@mumc.nl
authors.forename: M H G
authors.initials: MH
authors.lastname: Dremmen
authors.forename: P A M
authors.initials: PA
authors.lastname: Hofman
authors.forename: J R
authors.initials: JR
authors.lastname: Hof
authors.forename: R J
authors.initials: RJ
authors.lastname: Stokroos
authors.forename: A A
authors.initials: AA
authors.lastname: Postma
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002781:Cholesteatoma / Q000473:pathology* / Q000601:surgery*; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D017352:Echo-Planar Imaging / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000473:pathology* / Q000517:prevention & control; D011182:Postoperative Care / Q000379:methods; D011379:Prognosis; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D012888:Skull Neoplasms / Q000473:pathology* / Q000601:surgery*; D013701:Temporal Bone / Q000473:pathology* / Q000601:surgery; D016896:Treatment Outcome; D055815:Young Adult