title: Grading of endolymphatic hydrops using magnetic resonance imaging.
abstract: CONCLUSIONS
  Grading of endolymphatic hydrops in the vestibule and the cochlea using magnetic resonance imaging (MRI) is proposed (2008 Nagoya scale).
  
  
  OBJECTIVE
  To standardize the evaluation of endolymphatic hydrops in both the vestibule and the cochlea using MRI.
  
  
  METHODS
  The endolymphatic space was evaluated after intratympanic gadolinium injection using three-dimensional fluid attenuated (3D-FLAIR) MRI and three-dimensional real inversion recovery (3D-real IR) MRI.
  
  
  RESULTS
  A simple three-stage grading system was acceptable for hydrops in both the vestibule and the cochlea: none, mild, and significant. In the vestibule, the grading was determined by the ratio of the area of endolymphatic space to the vestibular fluid space (sum of the endolymphatic and perilymphatic spaces). Patients with no hydrops have a ratio of one-third or less, those with mild hydrops have between one-third and a half, and those with significant hydrops have a ratio of more than 50%. In the cochlea, patients classified as having no hydrops show no displacement of Reissner's membrane; those with mild hydrops show displacement of Reissner's membrane but the area of the endolymphatic space does not exceed the area of the scala vestibuli; and in those with significant hydrops the area of the endolymphatic space exceeds the area of the scala vestibuli.
authors.affiliation: Department of Otorhinolaryngology, Nagoya University School of Medicine, 65, Tsurumai-cho, Showa-ku, Nagoya 466-8550, Japan. tsutomun@med.nagoya-u.ac.jp
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Nakashima
authors.forename: Shinji
authors.initials: S
authors.lastname: Naganawa
authors.forename: Ilmari
authors.initials: I
authors.lastname: Pyykko
authors.forename: William P R
authors.initials: WP
authors.lastname: Gibson
authors.forename: Michihiko
authors.initials: M
authors.lastname: Sone
authors.forename: Seiichi
authors.initials: S
authors.lastname: Nakata
authors.forename: Masaaki
authors.initials: M
authors.lastname: Teranishi
mesh_terms: D003051:Cochlea / Q000473:pathology; D003287:Contrast Media / Q000008:administration & dosage; D018159:Endolymphatic Hydrops / Q000473:pathology*; D019786:Gadolinium DTPA / Q000008:administration & dosage; D006801:Humans; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D014722:Vestibule, Labyrinth / Q000473:pathology
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA