title: Intensity of gadolinium enhancement on MRI is useful in differentiation of intracochlear inflammation from tumor.
abstract: OBJECTIVE
  Magnetic resonance imaging is the gold standard in retrocochlear imaging; however, its role in management of inner ear diseases remains poorly defined. In this study, we investigate the utility of MRI in defining the nature of intracochlear pathology.
  
  
  METHODS
  A retrospective review of 11 patients with inner ear abnormalities on MRI between 2010 and 2013. Patients' diagnosis included cholesteatoma, labyrinthitis, meningitis, and intralabyrinthine schwannoma.
  
  
  METHODS
  Tertiary care hospital.
  
  
  METHODS
  T1, T2, and postcontrast signal intensities were measured within the lesion and normalized in reference to the contralateral normal cochlea. The following ratios were calculated: T1 postgadolinium lesion/contralateral cochlea, T2 lesion/contralateral cochlea and T1 lesion/contralateral cochlea. Statistical analysis was conducted using the unpaired Student's t test using IBM SPSS Statistics version 20.0.0.
  
  
  RESULTS
  The relative intensity ratios were useful in defining the nature of inner ear lesion. Normalized T1 postgadolinium lesion intensities were significantly higher in the tumor group (3.98 ± 0.880 versus 1.71 ± 0.370, p < 0.0002). Normalized T1 precontrast signal intensities were higher in tumors (1.33 ± 0.200 versus 0.842 ± 0.426, p < 0.0626), and T2 values were lower in tumors (0.838 ± 0.491 versus 1.10 ± 0.305, p < 0.317); however, these did not reach significance.
  
  
  CONCLUSIONS
  Intensity of gadolinium enhancement on MRI is useful in differentiation of inflammation from tumors; normalized T1 postgadolinium intensity ratio greater than 3 is strongly suggestive of intralabyrinthine tumor.
authors.affiliation: *New York University School of Medicine; †Department of Radiology, and ‡Department of Otolaryngology, Columbia University College of Physicians and Surgeons, New York, New York, U.S.A.
authors.forename: Robert
authors.initials: R
authors.lastname: Peng
authors.forename: Daniel
authors.initials: D
authors.lastname: Chow
authors.forename: Daniele
authors.initials: D
authors.lastname: De Seta
authors.forename: Anil K
authors.initials: AK
authors.lastname: Lalwani
mesh_terms: D000328:Adult; D000368:Aged; D003051:Cochlea / Q000473:pathology*; D015834:Cochlear Diseases / Q000473:pathology*; D003287:Contrast Media; D003937:Diagnosis, Differential; D004428:Ear Neoplasms / Q000473:pathology*; D005260:Female; D005682:Gadolinium; D006801:Humans; D007249:Inflammation / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D003287:Contrast Media; D005682:Gadolinium