Project Description

    choles_newCholesteatoma results from the presence of keratinizing epithelium within the middle ear. Acquired cholesteatoma can occur as sequelae of otitis media.  

   Squamous epithelium of the external canal can enter the middle ear through a perforation of the tympanic membrane or form a cholesteatomatous sac from a retraction pocket.  The keratinizing epithelium continues to desquamate, within the enclosed middle ear space, finally eroding bony structures.  

    The histological characteristics of cholesteatoma include a keratinizing epithelium with keratohyline granules, and exfoliated keratin.  There is an associated inflammatory response and a middle ear effusion.