title: Magnetic resonance imaging of the inner ear after both intratympanic and intravenous gadolinium injections.
abstract: CONCLUSIONS
  Using magnetic resonance imaging (MRI), endolymphatic hydrops could be visualized on both sides after intratympanic (IT) injection of gadolinium contrast agents (Gd) in one symptomatic ear and subsequent intravenous (IV) Gd injection. The MRI revealed a difference of intracochlear Gd distribution between the IT injection side and the contralateral IV side.
  
  
  OBJECTIVE
  Although the IT method allows greater enhancement of the perilymph, many patients feel reluctance in receiving the IT injection in asymptomatic ears. We attempted to evaluate endolymphatic space size on both sides without the IT injection in asymptomatic ears.
  
  
  METHODS
  In 10 patients with Meniere's disease, MRI was performed 24 h after the IT Gd injection in one symptomatic ear and 4 h after the IV Gd injection. The signal intensity of Gd in the basal and apical turns of the cochlea was evaluated.
  
  
  RESULTS
  The signal intensity in the scala tympani of the basal turn of the cochlea was 1.70 ± 0.60 on the IT + IV side and 0.42 ± 0.10 on the contralateral (IV) side. Gd was distributed uniformly in the scala tympani in the cochlea on the IV side, whereas it was strongly localized in the basal turn on the IT + IV side.
authors.affiliation: Department of Otorhinolaryngology, Nagoya University, Nagoya, Japan.
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Iida
authors.forename: Masaaki
authors.initials: M
authors.lastname: Teranishi
authors.forename: Tadao
authors.initials: T
authors.lastname: Yoshida
authors.forename: Hironao
authors.initials: H
authors.lastname: Otake
authors.forename: Michihiko
authors.initials: M
authors.lastname: Sone
authors.forename: Masahiro
authors.initials: M
authors.lastname: Kato
authors.forename: Mariko
authors.initials: M
authors.lastname: Shimono
authors.forename: Masahiro
authors.initials: M
authors.lastname: Yamazaki
authors.forename: Shinji
authors.initials: S
authors.lastname: Naganawa
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Nakashima
mesh_terms: D000328:Adult; D000368:Aged; D003287:Contrast Media / Q000008:administration & dosage*; D007758:Ear, Inner / Q000473:pathology; D018159:Endolymphatic Hydrops / Q000175:diagnosis*; D005260:Female; D019786:Gadolinium DTPA / Q000008:administration & dosage*; D006801:Humans; D007275:Injections, Intravenous; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D014432:Tympanic Membrane
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA