A guinea pig model of adhesive otitis media and the effect of tympanostomy.
OBJECTIVE
The pathophysiology and prevention strategies of adhesive otitis media were investigated using two animal otitis media models induced by the inoculation of a corrosive agent into the tympanic clefts of guinea pigs.


METHODS
In the first experiment, KANSUI (consisting of potassium carbonate and sodium carbonate) solution was injected into the left tympanic cleft of the guinea pigs. Five groups of five animals were sacrificed at 2 weeks, and at 1, 3, 6, and 12 months after inoculation to observe the pathological changes with time. In the second experiment, a similar otitis media model was induced in 18 guinea pigs. Tympanostomy was performed at 1 and 2 weeks after induction of the otitis media to eliminate inflammatory exudate from the tympanic cleft. Three groups of six animals were sacrificed at 1, 3, and 6 months after the tympanostomy to compare the differences in pathological changes between the groups with and without tympanostomy.


RESULTS
In the first experiment, severe mucosal injury to the middle ear mucosa was observed at 2 weeks, and at 1 and 3 months after inoculation, and the tympanic membrane (TM) had adhered to the promontorium at 3, 6 and 12 months after inoculation. In the second experiment, TM adhesion decreased following the tympanostomy.


CONCLUSIONS
It is suggested that severe injury to the middle ear mucosa caused TM adhesion during the process of wound healing, and that tympanostomy is effective in preventing adhesive otitis media.
Hashimoto
S
S
Department of Otolaryngology, Niigata University School of Medicine, Japan.
D000818:Animals; D002448:Cell Adhesion / Q000502:physiology; D004195:Disease Models, Animal; D004427:Ear Diseases / Q000209:etiology* / Q000601:surgery; D004431:Ear, External / Q000473:pathology; D007758:Ear, Inner / Q000473:pathology; D004724:Endoscopy / Q000379:methods; D006168:Guinea Pigs; D006984:Hypertrophy / Q000473:pathology; D008876:Middle Ear Ventilation / Q000379:methods; D010033:Otitis Media / Q000209:etiology* / Q000601:surgery; D000267:Tissue Adhesions / Q000473:pathology / Q000601:surgery; D014432:Tympanic Membrane / Q000473:pathology* / Q000601:surgery