Persistent otitis media with effusion: a new experimental model.
OBJECTIVE
Numerous mechanical animal models for the creation of otitis media with effusion (OME) have been described since the 1920s. However, there are many problems associated with these models, including high infection rates, unreliability, and high resolution rates. The aim of the current study was to create a suitable mechanical animal model that would produce a sterile and long-lasting effusion.


METHODS
A new technique using an external surgical approach on specific pathogen-free rats is described.


METHODS
The eustachian tubes of 56 rats were obstructed in the mid portion along the skull base with gutta percha.


RESULTS
All animals developed an effusion within 1 week of the procedure. The resolution rate was 8%, with 80% maintaining sterile effusions for up to 1 year.


CONCLUSIONS
This new procedure for an OME model has proved consistently reliable in creating a persistent and long-lasting effusion. It has a low infection rate and should benefit future studies on the prolonged effects of OME on the tympanic membrane and middle ear.
Russell
J D
JD
Department of Otolaryngology/Head and Neck Surgery, University College Dublin, Ireland. Russellj@indigo.ie
Giles
S J
SJ
D000818:Animals; D004195:Disease Models, Animal; D008297:Male; D010034:Otitis Media with Effusion / Q000473:pathology; D051381:Rats; D017208:Rats, Wistar