Cholesteatoma is a sac in the middle ear, lined by keratinizing stratified squamous epithelium containing desquamated epithelium as Keratin Debris.
1. RETRACTION POCKET THEORY (WITTMAN’S THEORY):
Eustachian Tube obstruction
Negative pressure in middle ear cavity.
Formation of retraction pocket at attic region.
Hamper normal migratory action of epithelium of external auditory meatus.
Accumulation of desquamated epithelium in the attic.
Pressure necrosis of TM.
2. BASAL CELL HYPERPLASIA:
Basal cells of germinal layer of skin.
Proliferate under influence of infection.
Lay down keratinizing squamous epithelium.
3. EPITHELIAL INVASION:
Epithelium from meatus or outer drum surface.
Migrate to middle ear through a pre-existing perforation (marginal type)
Recurrent or chronic infection.
Columnar epithelium →(Metaplasia)→ Squamous epithelium → Secondary cholesteatoma.
5. IMPLANTATION THEORY:
At the time of middle ear surgery squamous epithelium may get implanted.
1. Ear discharge.
2. Conductive hearing loss.
3. Pain in ear.
4. Balance disruption.
8. Bleeding from ear.
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