Intratympanic ciprofloxacin & the human labyrinthine sampling model (HLSM)

Becvarovski Z, Kartush JM, Bojrab DI.

Michigan Ear Institute, Farmington Hills; Providence Hospital, SouthfieldWayne State University, Department of Otolaryngology, Detroit, Michigan, USA.


OBJECTIVE: The aim of the study was to investigate the potential absorption of intratympanic ciprofloxacin through the human round window membrane.

STUDY DESIGN: 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.

 CONCLUSION: 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.

Laryngoscope 2002 Apr;112(4):686-8