Cholesteatoma is a destructive and expanding growth consisting of keratinizing squamous epithelium in the middle ear and/or mastoid process.

This can result in the destruction of the bones of the middle ear (ossicles), as well as growth through the base of the skull into the brain.

[4] Other less common symptoms (all less than 15%) of cholesteatoma may include pain, balance disruption, tinnitus, earache, headaches and bleeding from the ear.

If untreated, a cholesteatoma can eat or cause erosion of the three small bones located in the middle ear (the malleus, incus and stapes, collectively called ossicles).

Both the acquired as well as the congenital types of the disease can affect the facial nerve that extends from the brain to the face and passes through the inner and middle ear and leaves at the anterior tip of the mastoid bone, and then rises to the front of the ear and extends into the upper and lower face.

[8] Keratin-filled cysts that grow medial to the tympanic membrane are considered to be congenital if they fulfill the following criteria (Levenson's criteria):[3] Congenital cholesteatomas occur at three important sites: the middle ear, the petrous apex, and the cerebropontinio angle.

They are most often found deep to the anterior aspect of the ear drum, and a vestigial structure, the epidermoid formation, from which congenital cholesteatoma may originate, has been identified in this area.

[9][10] More commonly, keratin accumulates in a pouch of tympanic membrane which extends into the middle ear space.

Non-ionizing radiation imaging techniques (MRI) may be suitable to replace a CT scan, if determined necessary by a physician.

Once the diagnosis of cholesteatoma is made in a patient who can tolerate a general anesthetic, the standard treatment is to surgically remove the growth.

The direct line of view dictated by that approach necessitates using the mastoid as the access port to the middle ear.

Such causes can include, for example, poor Eustachian tube function, which results in retraction of the ear drum, and failure of the normal outward migration of skin.

[27] In a retrospective study of 345 patients with middle ear cholesteatoma operated on by the same surgeon, the overall 5-year recurrence rate was 11.8%.

[31] Recent findings indicate that the keratinizing squamous epithelium of the middle ear could be subjected to human papillomavirus infection.