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Creating a stable tympanic membrane perforation using mitomycin C.

R C O'Reilly·S A Goldman·S A Widner·S P Cass
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Abstract

OBJECTIVE: To determine the ability of topically applied mitomycin C to create a stable tympanic membrane perforation. STUDY DESIGN AND SETTING: Twenty-four rats underwent subtotal removal of the tympanic membranes bilaterally. Forty ears received 0.2 mg/ml of mitomycin C. The remaining 8 received phosphate-buffered saline solution (control). Photographs taken every 3 to 5 days for 44 days were digitally scanned and computer analyzed to calculate the percentage of residual perforation. Application of solutions, photography, and data analysis were performed in a blinded fashion. RESULTS: The mitomycin C treated ears had delayed closure time and healing rate (from day 0 to 25) compared to the control group. All controls healed by day 14. By day 44, 92.5% of the mitomycin C treated ears healed. CONCLUSION: Mitomycin C prolongs the closure and healing rate of myringotomies in rat tympanic membranes. SIGNIFICANCE: Myringotomy with concurrent mitomycin C application may be useful for creating an animal model for chronic tympanic membrane perforation and should be tested in human beings as a method to maintain myringotomy patency for long-term ventilation.

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Alkylating AgentsAnimalsChronic DiseaseDisease Models, AnimalMaleMiddle Ear VentilationMitomycinMyringoplastyRatsRats, Long-EvansTime FactorsTympanic Membrane PerforationJournal Article

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BibTeXRIS

R C O'Reilly, S A Goldman, S A Widner, S P Cass. 2001. Creating a stable tympanic membrane perforation using mitomycin C.. https://doi.org/10.1067/mhn.2001.112199

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