title: Postauricular hypodermic injection to treat inner ear disorders: experimental feasibility study using magnetic resonance imaging and pharmacokinetic comparison.
abstract: BACKGROUND
  To investigate the feasibility of postauricular hypodermic injection for treating inner ear disorders, we compared perilymph pharmacokinetics for postauricular versus intravenous injection, using magnetic resonance imaging, in an animal model.
  
  
  METHODS
  Twelve albino guinea pigs were divided randomly into two groups and administered gadopentetate dimeglumine via either a postauricular or an intravenous bolus injection. A 7.0 Tesla magnetic resonance imaging system was used to assess the signal intensities of gadolinium-enhanced images of the cochlea, as a biomarker for changes in gadopentetate dimeglumine concentration in the perilymph. Pharmacokinetic parameters were calculated based on these signal intensity values.
  
  
  RESULTS
  Guinea pigs receiving postauricular injection showed longer times to peak signal intensity, longer elimination half-life, longer mean residence time and a greater area under the signal-time curve (from pre-injection to the last time point) (p < 0.05).
  
  
  CONCLUSIONS
  Postauricular injection shows potential as an efficient drug delivery route for the treatment of inner ear disorders.
authors: Department of Otolaryngology, Head and Neck Surgery, People's Hospital, Peking University, Beijing, China.
authors: J
authors: J
authors: Li
authors: L
authors: L
authors: Yu
authors: R
authors: R
authors: Xia
authors: F
authors: F
authors: Gao
authors: W
authors: W
authors: Luo
authors: Y
authors: Y
authors: Jing
mesh_terms: D000279:Administration, Cutaneous; D000818:Animals; D019540:Area Under Curve; D003287:Contrast Media / Q000493:pharmacokinetics*; D004195:Disease Models, Animal; D016503:Drug Delivery Systems / Q000379:methods*; D005240:Feasibility Studies; D019786:Gadolinium DTPA / Q000493:pharmacokinetics*; D006168:Guinea Pigs; D007759:Labyrinth Diseases / Q000188:drug therapy*; D008279:Magnetic Resonance Imaging; D008297:Male; D010498:Perilymph / Q000378:metabolism
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA