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[A guinea pigs model of otitis media with effusion caused by reversible Eustachian tube obstruction].

OBJECTIVE
To develop a animal model for acute otitis media with effusion (OME).


METHODS
In 22 guinea pigs, the left nasal orifice of Eustachian tube was approached via a transpalatal incision and obstructed with polyvinyl acetal material. Right ears were set as the control. Then all the ears were evaluated by otomicroscopy every day. Seven, 14 and 21 days after the intervention, six guinea pigs were killed for histologic study.


RESULTS
Of the 22 guinea pigs included in this study, 20 ears (90.9%) were found to have effusion 3 - 7 days after the operation, two cases were excluded for purulent otorrhea 10 days postoperatively. The epithelium initially developed hyperplasia, and the submucosa showed vascular and lymphatic dilatations with inflammatory cells infiltration. None of the contralateral control ears had evidence of disease by otomicroscopic examination and histologic study.


CONCLUSION
This experimental methods provoked reproducible pathologic characteristics similar to those for otitis media with effusion.