Benign tumor usually found in middle ear and mastoid region.Encyclopedia Entry for Cholesteatoma :Cholesteatoma. Cholesteatoma can be a birth defect (congenital). It more commonly occurs as a result of chronic ear infection. The eustachian tube helps equalize pressure in the middle ear. When it is not working well, negative pressure can build up and pull part of the eardrum (tympanic membrane) inward. This creates a pocket or cyst that fills with old skin cells and other waste material. The cyst may become infected or get bigger. This can cause the breakdown of some of the middle ear bones or other structures of the ear. This can affect hearing, balance, and possibly the function of the facial muscles.Symptoms include: Dizziness Drainage from the ear , which can be chronic Hearing loss in one ear Sensation of ear fullness or pressure.An ear exam may show a pocket or opening (perforation) in the eardrum, often with drainage. A deposit of old skin cells may be seen with a microscope or an otoscope, which is a special instrument to view the ear. Sometimes a group of blood vessels may be seen in the ear. The following tests may be performed to rule out other causes of dizziness: CT scan Electronystagmography.Cholesteatomas very often continue to grow if they are not removed. Surgery is most often successful. However, you may need the ear cleaned by a health care provider from time to time. Another surgery may be needed if the cholesteatoma comes back.Complications may include: Brain abscess (rare) Erosion into the facial nerve (causing facial paralysis ) Meningitis Spread of the cyst into the brain.Call your provider if ear pain, drainage from the ear, or other symptoms occur or worsen, or if hearing loss occurs.Prompt and thorough treatment of chronic ear infection may help prevent cholesteatoma.Chronic ear infection - cholesteatoma; Chronic otitis - cholesteatoma.Tympanic membrane Tympanic membrane.Chole RA. Chronic otitis media, mastoiditis, and petrositis.