 If untreated, a cholesteatoma can eat into the three small bones located in the middle ear (the malleus, incus and stapes, collectively called ossicles), which can result in nerve deterioration, deafness, imbalance and vertigo.It can also affect and erode, through the enzymes it produces, the thin bone structure that isolates the top of the ear from the brain, as well as lay the covering of the brain open to infection with serious complications (rarely even death due to brain abscess and sepsis).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.