Applicability of autologous incus: the influence of age and localization of cholesteatoma.

There is a correlation between macroscopic and histologic changes of incus in chronic otitis with cholesteatoma. The incidence and types of damage of auditory ossicles in chronic otitis media were extensively studied, but except some studies on reoperations there are no morphometric studies of human auditory ossicles in chronic otitis media. In order to define the rate of ossicular applicability for tympanoplasties in different macroscopic forms of damage, we analysed histologic changes of human incudes in correlation to their macroscopic alterations. Histomorphometric study of 82 intraoperatively removed human incudes, from chronic otitis media with cholesteatoma (attic, sinus, tensa cholesteatoma), was performed. They were divided according to the age of patients and localization of cholesteatoma. Erosions, vitality, vascular areas, osteomyelitic zones, and applicability of ossicles were measured. Progressive increase of erosions, decrease of vitality, dilatation of vascular spaces and osteomyelitic areas, and decrease of rate of potential applicability for tympanoplasties were found. Residual osteomyelitis was present in incudes with advanced external osteitis and ossicular defect. Macroscopic changes of incudes in cholesteatoma and their histologic structure correlate. Localisation of cholesteatoma is important for ossicular damage. Defects of long process with external osteitis of incudes and more intense pathological changes demand their removal and use of other reconstructive materials for tympanoplasties in order to avoid tympanoplasty failure.