Abstract
The author reviews and discusses the major theories on the development of aural cholesteatoma.
1. Cholesteatoma developing at the PSQ
This is a type of cholesteatoma described by Harbermann (1888) as a kind of secondary cholesteatomas following necrotizing otitis at the PSQ area. Some however, regard this as a type of primary cholesteatoma developing due to retraction of the tympanic membrane (Tumarkin 1961).
The author considers that the cholesteatoma in the PSQ is, most likely, cholesteatoma of primary type.
2. Immingration theory
The authors examined the canal skins and eardrums of the several cases of attic type cholesteatoma in children but failed to confirm the immigration of the basal cells into the granulation tissue.
In animial experiments using rabbits, in which the author obliterated the eustachian tube papillary immigration of the basal cells was seen only in ears with perforation of the eardrum, and retraction cholesteatoma only in ears without perforation.
The author concluded that negative pressure and inflammation in the middle ear would precipitate the growth of the eipthelial cells of the pars flaccida, and then subsequent retraction will give rise to formation of cholesteatoma.
