Definition of Cholesteatoma:

Cholesteatoma is a type of skin cyst located in the middle ear.

Causes, incidence, and risk factors:

Cholesteatoma can be a birth defect (congenital), but it more commonly occurs as a complication of chronic ear infection.

Poor function in the eustachian tube leads to negative pressure in the middle ear. This pulls a part of the eardrum (tympanic membrane) into the middle ear, creating a pocket or cyst that fills with old skin cells and other waste material. The cyst can become infected. The cyst may get bigger and break down some of the middle ear bones or other structures of the ear, affecting hearing, balance, and possibly function of the facial muscles.