title: Numerical assessment of cholesteatoma by signal intensity on non-EP-DWI and ADC maps.
abstract: OBJECTIVE
  To establish a methodology for magnetic resonance imaging (MRI) assessment in the diagnosis of cholesteatoma using signal intensity on BLADE diffusion-weighted MRI (BLADE-DWI) and apparent diffusion coefficient (ADC) mapping.
  
  
  METHODS
  Retrospective case series.
  
  
  METHODS
  University hospital.
  
  
  METHODS
  Participants comprised 29 patients who underwent middle ear surgery and in whom preoperative differential diagnosis between cholesteatoma and other middle ear diseases was difficult using local and computed tomographic findings and required BLADE-DWI.
  
  
  METHODS
  Signal intensity ratio (SIR) between the affected region of the middle ear and the pons measured by BLADE-DWI and on ADC maps was evaluated numerically. SIR in an area located near the target lesion in each case was used as a control. Values were compared between both cases in which cholesteatoma was histopathologically confirmed (cholesteatoma group) and cases in which cholesteatoma was excluded on histopathologic examination (noncholesteatoma group).
  
  
  METHODS
  Imaging and histopathologic findings.
  
  
  RESULTS
  SIR on BLADE-DWI was significantly higher in the cholesteatoma group than in the noncholesteatoma group, although both groups showed significantly higher SIR in the target lesion than in the control area. Moreover, SIR on ADC maps was significantly lower in the cholesteatoma group than in the noncholesteatoma group. The clear cutoff value of SIR on ADC maps was 1.5.
  
  
  CONCLUSIONS
  The combination of BLADE-DWI and ADC mapping offers a useful imaging tool for accurate detection of middle ear cholesteatoma. Use of SIR can numerically differentiate between cholesteatoma and noncholesteatoma.
authors.affiliation: Departments of *Otorhinolaryngology, and †Radiology, Nagoya University Graduate School of Medicine, Nagoya, Japan.
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Suzuki
authors.forename: Michihiko
authors.initials: M
authors.lastname: Sone
authors.forename: Tadao
authors.initials: T
authors.lastname: Yoshida
authors.forename: Hironao
authors.initials: H
authors.lastname: Otake
authors.forename: Ken
authors.initials: K
authors.lastname: Kato
authors.forename: Masaaki
authors.initials: M
authors.lastname: Teranishi
authors.forename: Kenji
authors.initials: K
authors.lastname: Suga
authors.forename: Takafumi
authors.initials: T
authors.lastname: Nakada
authors.forename: Shinji
authors.initials: S
authors.lastname: Naganawa
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Nakashima
mesh_terms: D000328:Adult; D000368:Aged; D018424:Cholesteatoma, Middle Ear / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D003937:Diagnosis, Differential; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013506:Otologic Surgical Procedures; D011300:Preoperative Care; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted; D014057:Tomography, X-Ray Computed; D055815:Young Adult