Final answer:
The formation of secondary cholesteatoma is most commonly attributed to a retraction of the tympanic membrane due to chronic middle ear disease, creating a pocket that fills with epithelium and debris. This condition is treated surgically to prevent complications.
Step-by-step explanation:
The most accepted theory of the formation of secondary cholesteatoma involves the retraction or invagination of the tympanic membrane (eardrum) due to chronic middle ear disease. This invagination can create a pocket or cyst that fills with squamous epithelium and keratin debris, leading to the development of a cholesteatoma. The accumulation of this debris can lead to infection, bone erosion, and various complications in the ear. Factors contributing to the formation include poor Eustachian tube function, chronic otitis media, and a history of middle ear infections or surgeries.
Secondary cholesteatomas are distinguished from primary cholesteatomas, which are thought to arise from embryonic cell rests or defects in the tympanic membrane without prior infection or trauma. In contrast, secondary cholesteatomas are always associated with a history of ear disease. Treatment typically involves surgical removal of the cholesteatoma to prevent further damage and complications.