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Updated: Aug 15, 2026

Dissection of the Auditory Bulla in Postnatal Mice: Isolation of the Middle Ear Bones and Histological Analysis
Published on: January 4, 2017
Squamous metaplasia of the middle ear mucosa during vitamin A deprivation
Abstract:
Adult and juvenile albino rats were maintained on a vitamin A-free test diet for 2 to 28 weeks. Histologic study of the middle ear and eustachian tube mucosa of these animals showed extensive focal squamous metaplasia when compared with the control group. Keratinization of large areas of normally columnar, ciliated epithelium was observed without frank keratoma formation. In over half of the most vitamin A-deficient animals, acute otitis media with effusion was found. It is hypothesized that vitamin A deficiency disrupts the mucocilliary clearing mechanism in the middle ear and eustachian tube, which may lead to effusion and otitis media.
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