title: Visualization of endolymphatic hydrops in Ménière's disease after single-dose intravenous gadolinium-based contrast medium: timing of optimal enhancement.
abstract: OBJECTIVE
  Visualization of endolymphatic hydrops (EH) in patients with Ménière's disease (MD) is now possible by heavily T(2)-weighted 3-dimensional fluid-attenuated inversion recovery (hT(2)W-3D-FLAIR) obtained 4 hours after intravenous (IV) administration of single dose gadolinium-based contrast medium (GBCM). Although maximum enhancement has been reported 4 hours after contrast administration in healthy volunteers, the timing of optimal enhancement in patients with MD is not reported. We investigated if that optimal timing is earlier or later than 4 hours.
  
  
  METHODS
  We evaluated 10 consecutive patients with suspected MD whom we randomly divided into 2 groups. We obtained hT(2)W-3D-FLAIR before GBCM administration and 10 min, 3.5 hours, and 4 hours after GBCM administration in Group A and before and 10 min, 4 hours, and 4.5 hours after GBCM administration in Group B. We compared signal intensity ratio (SIR) values of the perilymph and pons between 3.5 and 4 hours in Group A and between 4 and 4.5 hours in Group B and evaluated grades of EH at 3.5 and 4 hours in Group A and at 4 and 4.5 hours in Group B.
  
  
  RESULTS
  SIR values did not differ significantly between 3.5 and 4 hours in Group A and between 4 and 4.5 hours in Group B. However, SIR values at 4 hours were significantly higher in Group A than Group B. Grades of EH agreed between 3.5 and 4 hours in Group A and between 4 and 4.5 hours in Group B.
  
  
  CONCLUSIONS
  The optimal timing of contrast enhancement in patients with suspected MD remains unclear, but evaluation of EH may be possible from 3.5 to 4.5 hours after contrast administration.
authors.affiliation: Department of Radiology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Shouwa-ku, Nagoya 466-8550, Japan. naganawa@med.nagoya-u.ac.jp
authors.forename: Shinji
authors.initials: S
authors.lastname: Naganawa
authors.forename: Masahiro
authors.initials: M
authors.lastname: Yamazaki
authors.forename: Hisashi
authors.initials: H
authors.lastname: Kawai
authors.forename: Kiminori
authors.initials: K
authors.lastname: Bokura
authors.forename: Michihiko
authors.initials: M
authors.lastname: Sone
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Nakashima
mesh_terms: D000328:Adult; D000368:Aged; D003287:Contrast Media / Q000008:administration & dosage; D018159:Endolymphatic Hydrops / Q000473:pathology; D005260:Female; D005682:Gadolinium / Q000008:administration & dosage*; D006801:Humans; D007275:Injections, Intravenous; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008575:Meniere Disease / Q000473:pathology*; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media; D005682:Gadolinium