title: Comparison of echo-planar diffusion-weighted imaging and delayed postcontrast T1-weighted MR imaging for the detection of residual cholesteatoma.
abstract: OBJECTIVE
  Echo-planar diffusion-weighted imaging (DWI) and delayed postcontrast T1-weighted MR imaging (DPI) have been proposed in previous studies to detect residual middle ear cholesteatomas, with varying results. We assessed and compared these 2 techniques in patients with canal wall-up tympanoplasty.
  
  
  METHODS
  This was a prospective cohort study. Patients who underwent surgery for middle ear cholesteatoma had CT scanning 9 months after the surgery. If opacity was observed (64%) on CT scans, DWI and DPI were performed before second-look surgery. CT, MR imaging, and surgical data were available for 31 patients. Charts were reviewed independently by 3 blinded examiners. Interobserver agreement for MR imaging was calculated (Cohen kappa). Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for these techniques: 1) alone or in association, and 2) according to the residual cholesteatoma size measured during surgery.
  
  
  RESULTS
  Interobserver agreement was better for DWI (kappa = 0.81) than for DPI (kappa = 0.51). Sensitivity, specificity, PPV, and NPV values were 60%, 72.73%, 80%, and 50%, respectively, with DWI; and 90%, 54.55%, 78.26%, and 75%, respectively, with DPI. With cholesteatomas >5 mm, the sensitivity and specificity of DWI reached 100% and 88%, respectively, with values for DPI reaching 100% and 80%, respectively. The association of both techniques only allowed improvements in the specificity for lesions >5 mm.
  
  
  CONCLUSIONS
  Both techniques gave acceptable results for residual cholesteatoma detection. DWI is more specific but less sensitive than DPI. Their concurrent use may benefit patients by avoiding undue surgery.
authors.affiliation: Ear, Nose, and Throat Department, University Hospital Gui de Chauliac, Montpellier, France. f-venail@chu-montpellier.fr
authors.forename: F
authors.initials: F
authors.lastname: Venail
authors.forename: A
authors.initials: A
authors.lastname: Bonafe
authors.forename: V
authors.initials: V
authors.lastname: Poirrier
authors.forename: M
authors.initials: M
authors.lastname: Mondain
authors.forename: A
authors.initials: A
authors.lastname: Uziel
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D018424:Cholesteatoma, Middle Ear / Q000175:diagnosis* / Q000601:surgery*; D038524:Diffusion Magnetic Resonance Imaging; D004432:Ear, Middle / Q000473:pathology / Q000601:surgery; D017352:Echo-Planar Imaging; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011183:Postoperative Complications / Q000175:diagnosis*; D011446:Prospective Studies; D012680:Sensitivity and Specificity