Patients with chronic eustachian tube problems are not able to equalize the pressure in the space behind the ear drum called the middle ear. This results in negative pressure in the middle ear which pulls the ear drum inwards, toward the middle ear space. This is referred retraction pocket. The upper part of the ear drum is very thin and flimsy. In cases of chronic eustachian tube problems, this area is predisposed to forming a retraction pocket. This pocket can then fill with skin debris over time forming a ball of skin called a cholesteatoma. As bacteria gets trapped within the skin, it can cause recurrent infections with pain and drainage. The cholesteatoma will also tend to damage and erode the underlying hearing bones. Thus, there is usually hearing loss associated with a cholesteatoma. The cholesteatoma can usually be easily identified in the ENT office using a hand-held otoscope or microscope.
Cholesteatoma is generally considered to be a surgical condition. In some cases, if the patient is not able to undergo surgery, the cholesteatoma can be managed conservatively with routine cleaning in the ENT office and using antibiotic drops when infection develops. However, this will not make the problem go away. As cholesteatomas tend to progress with time and start to damage other important structures in the area, the usual recommendation is to remove the skin pocket and repair the ear drum in a procedure called a tympanomastoidectomy. This is a surgery conducted in the operating room with the patient under general anesthesia. Sometimes a small and limited cholesteatoma can be removed working through the ear canal with a microscope. As cholesteatomas enlarge, they will expand into the mastoid bone which is the bump of bone felt just behind the ear. For this reason, a mastoidectomy is often needed in order to gain access to the deeper portion of the cholesteatoma. In this part of the procedure, an incision is made behind the ear to expose the mastoid bone which is then drilled away to expose and clean away the cholesteatoma. Once the cholesteatoma has been removed, the hearing bones are inspected and repaired with a small prosthesis if necessary in an effort to improve hearing. The ear drum is then reconstructed using some of the patient’s tissue. Sometimes a second surgery will be needed about one year later to ensure that there is no further skin growing behind the ear drum. Tympanomastoidectomy surgery is also performed in cases where cholesteatoma is not present but there is chronic infection in the middle ear and mastoid bone.