Chronic tympanic membrane perforation in an animal model.

Objective: The aim of this study was to revalidate and reproduce a chronic tympanic membrane perforation animal model.

Study Design: Prospective, animal study.

Methods: Eight female chinchillas underwent bilateral thermal myringotomy. The edges of the perforation were folded inward using microflaps. The perforations were followed over time to monitor the course of closure.

Results: Two animals were excluded from the study because of ear infection. None of the other tympanic membrane perforations remained open. The closing time varied from 4 to 6 weeks.

Conclusions: Our findings demonstrate that the thermal myringotomy combined with infolding technique is not a reliable and consistent method to create a chronic tympanic membrane perforation. The closing time is shorter than expected and varies among the study subjects. There is a clear need for developing a reliable chronic tympanic membrane perforation model.