title: Intratympanic ciprofloxacin and the human labyrinthine sampling model.
abstract: OBJECTIVE
  The aim of the study was to investigate the potential absorption of intratympanic ciprofloxacin through the human round window membrane.
  
  
  METHODS
  A prospective study.
  
  
  METHODS
  Ciprofloxacin was instilled into the middle ear of 10 patients undergoing acoustic tumor removal. The lateral semicircular canal and vestibule were subsequently opened and, using a microsyringe, labyrinthine fluid was aspirated. A sample each of serum and cerebrospinal fluid was also drawn.
  
  
  RESULTS
  Into each middle ear, 0.5 mL ciprofloxacin (0.3%) was instilled. The time interval between the ciprofloxacin application to the round window membrane and sampling of labyrinthine fluid and plasma ranged from 9 to 120 minutes. There was no measurable ciprofloxacin in the labyrinthine fluid, cerebrospinal fluid, or serum of 10 patients.
  
  
  CONCLUSIONS
  The lack of measurable absorption of intratympanic ciprofloxacin into the inner ear indicates that the chance of ototoxicity when ciprofloxacin is used clinically, even in the presence of a tympanic membrane perforation, is low.
authors.affiliation: Michigan Ear Institute, Farmington Hills, USA. zb@ent.com.au
authors.forename: Zoran
authors.initials: Z
authors.lastname: Becvarovski
authors.forename: Jack M
authors.initials: JM
authors.lastname: Kartush
authors.forename: Dennis I
authors.initials: DI
authors.lastname: Bojrab
mesh_terms: D000368:Aged; D000890:Anti-Infective Agents / Q000008:administration & dosage / Q000493:pharmacokinetics*; D002939:Ciprofloxacin / Q000008:administration & dosage / Q000493:pharmacokinetics*; D007758:Ear, Inner / Q000378:metabolism; D005260:Female; D006801:Humans; D007761:Labyrinthine Fluids / Q000737:chemistry; D008297:Male; D011446:Prospective Studies; D012405:Round Window, Ear; D014432:Tympanic Membrane
chemical_list: D000890:Anti-Infective Agents; D002939:Ciprofloxacin