title: Comparison of contrast effect on the cochlear perilymph after intratympanic and intravenous gadolinium injection.
abstract: OBJECTIVE
  3D-FLAIR imaging 24 hours after intratympanic gadolinium injection (IT-method) or 4 hours after IV injection (IV-method) has been used to visualize the endolymphatic hydrops in Ménière disease. The purpose of this study was to compare the degree of perilymph enhancement with the 2 methods and the perilymph contrast-effect difference with the IV-method in both sides in patients with unilateral Ménière disease.
  
  
  METHODS
  Sixty-one patients with Ménière disease or sudden SNHL were included in this study. Thirty-nine patients who underwent the unilateral IT-method (Gd-DTPA was diluted 8-fold with saline) and 22 patients who underwent the IV-method (a double-dose of Gd-HP-DO3A; 0.4 mL/kg body weight [ie, 0.2 mmol/kg body weight]) at 3T were analyzed retrospectively. Regions of interest of the cochlear perilymph and the medulla oblongata were determined on each image, and the signal-intensity ratio between the 2 (CM ratio) was subsequently evaluated. The differences in the CM ratio between the 2 methods (Student t test) and the IV-method CM ratio between the affected and unaffected sides in patients with unilateral Ménière disease (paired t test) were evaluated.
  
  
  RESULTS
  The IT-method CM ratio (2.98 ± 1.15, n = 39) was higher than the IV-method CM ratio (1.61 ± 0.60, n = 44; P < .001). In patients with unilateral Ménière disease who underwent the IV-method (n = 9), the CM ratio of the affected side (1.86 ± 0.74) was higher than that of the unaffected side (1.29 ± 0.31, P < .05).
  
  
  CONCLUSIONS
  In general, the IT-method provides higher perilymph enhancement than the IV-method. In the patients with unilateral Ménière disease who underwent the IV-method, the affected side had a higher contrast effect.
authors.affiliation: Department of Radiology, Nagoya University Graduate School of Medicine, Nagoya, Japan. yamazaki@med.nagoya-u.ac.jp
authors.forename: M
authors.initials: M
authors.lastname: Yamazaki
authors.forename: S
authors.initials: S
authors.lastname: Naganawa
authors.forename: M
authors.initials: M
authors.lastname: Tagaya
authors.forename: H
authors.initials: H
authors.lastname: Kawai
authors.forename: M
authors.initials: M
authors.lastname: Ikeda
authors.forename: M
authors.initials: M
authors.lastname: Sone
authors.forename: M
authors.initials: M
authors.lastname: Teranishi
authors.forename: H
authors.initials: H
authors.lastname: Suzuki
authors.forename: T
authors.initials: T
authors.lastname: Nakashima
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003051:Cochlea / Q000473:pathology; D003287:Contrast Media / Q000008:administration & dosage; D005260:Female; D019786:Gadolinium DTPA / Q000008:administration & dosage*; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D015552:Injections, Intralesional; D007275:Injections, Intravenous; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008575:Meniere Disease / Q000473:pathology*; D008875:Middle Aged; D010498:Perilymph / Q000166:cytology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014432:Tympanic Membrane / Q000473:pathology*; D055815:Young Adult
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA