Determination of ototoxicity of common otic drops using isolated cochlear outer hair cells.
OBJECTIVE
Otic drops are commonly used not only for otitis externa, but also for otorrhea in the presence of tympanostomy tubes or tympanic membrane perforations. Many studies have demonstrated the ototoxicity of common otic preparations such as Cortisporin otic drops (Monarch Pharmaceuticals, Bristol, TN). The purpose of this study was to assess the relative ototoxicity of common otic preparations by direct exposure to isolated cochlear outer hair cells (OHCs).


METHODS
OHCs from adult chinchilla cochlea were exposed to standard bathing solution (control), acetic acid, Acetasol HC (Alpharma USPD Inc., Baltimore, MD), Gentacidin (CIBA Vision Ophthalmics, Atlanta, GA), and Tobradex (Alcon, Fort Worth, TX). The cells were observed using an inverted microscope, and the images were recorded in digital still-frame and video, and analyzed on the Image Pro-Plus 3.0 program (Media Cybernetics, Silver Spring, MD).


CONCLUSIONS
As measured by time to cell death and change in morphology of OHCs, acetic acid with or without hydrocortisone was most toxic to OHCs. Cortisporin was more cytotoxic than gentamicin and Tobradex.
Jinn
T H
TH
Division of Otolaryngology--Head and Neck Surgery, Department of Surgery, Loma Linda University School of Medicine and Jerry L Pettis Memorial Veterans Administration Hospital, Loma Linda, California, USA.
Kim
P D
PD
Russell
P T
PT
Church
C A
CA
John
E O
EO
Jung
T T
TT
D019342:Acetic Acid / Q000633:toxicity*; D000287:Administration, Topical; D000818:Animals; D048429:Cell Size / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D002682:Chinchilla; D004338:Drug Combinations; D005839:Gentamicins / Q000633:toxicity*; D018072:Hair Cells, Auditory, Outer / Q000000981:diagnostic imaging / Q000187:drug effects*; D006854:Hydrocortisone / Q000633:toxicity*; D009355:Neomycin / Q000633:toxicity*; D011112:Polymyxin B / Q000633:toxicity*; D014031:Tobramycin / Q000633:toxicity*; D014463:Ultrasonography
D004338:Drug Combinations; D005839:Gentamicins; C033225:hydrocortisone, neomycin, polymyxin B drug combination; D009355:Neomycin; D011112:Polymyxin B; D019342:Acetic Acid; D014031:Tobramycin; D006854:Hydrocortisone