A cholesteatoma is a skin growth that occurs in the middle ear behind the eardrum. This condition usually results from poor Eustachian tube function concurrent with middle ear infection (otitis media), but can also be present at birth. The condition is treatable, but can only be diagnosed by medical examination. Over time, untreated cholesteatoma can lead to bone erosion and spread of the ear infection to localized areas such as the inner ear and brain. If untreated, deafness, brain abscess, meningitis, and death can occur.