The Medical Consumer's Advocate

Life after mastoidectomy

The writer's mother, who is almost 70, had an operation when she was in her 20s in which her ear drum and mastoid bone were removed. This was done as a treatment for severe ear infection. She now sees an ENT regularly for "scar tissue removal" from her ear. Her ENT wants her to have an operation to improve her hearing, yet she is comfortable being deaf in one ear. The writer wants to know whether an operation would help her mother, and whether the "scar tissue removal" is really necessary.

A: First, an anatomy lesson. The ear canal is partly bony and partly cartilaginous. The bony portion is that part which is closest to the ear drum. The posterior bony canal wall (i.e., the canal wall closest to the back of the head) is part of the mastoid bone; the mastoid bone is that large, round bone which you can feel if you place your fingertips just behind your ear lobe.

Within the mastoid bone, there is a honeycomb of "air cells." In other words, the mastoid is not a solid bone, but rather it contains numerous tiny air pockets. These air pockets are connected to the BIG air pocket behind the ear drum. This big air pocket is known as the "middle ear space."

The operation your mom had is known as a mastoidectomy. The most common reason to perform this operation was (and still is) an exceptionally aggressive middle ear infection, one which has begun to destroy the delicate bony walls of the mastoid air cells. Such infections, when left untreated, can lead to meningitis (infection of the tissues that surround the brain) or brain abscess, and can be quite deadly.

Back in the 50's, when your mom had her mastoidectomy, it was very common to remove the posterior canal wall as part of this procedure. (Nowadays, many ENTs try to leave the canal wall intact, but in cases of extensive infection we still may find it necessary to "take the canal wall down.") The outer (cartilaginous) part of the canal was usually left relatively intact. This operation left the patient with a flask-shaped "cavity." The outer part of the canal was still roughly cylindrical, but as you look towards the ear drum (or what used to be the ear drum) the space becomes very wide– you would be looking into the space left by the absence of the posterior canal wall and mastoid bone.

This cavity is typically skin-lined, and it tends to accumulate wax and skin debris. The ENT is NOT removing scar tissue, but is removing these debris. If the debris are not removed, they can become a great breeding ground for bacteria and fungi. This in turn can lead to foul-smelling ear drainage, ear pain, itching, and even ringing (tinnitus) or dizziness. It is impossible to tell you how often your mom needs her cavity cleaned of debris; some folks need this procedure every 3 or 4 months, and some go for years without ever needing to be cleaned.

Your first question is a much tougher one to answer. It is certainly possible that your mom’s surgeon may be able to restore her hearing. Here are the requirements for reasonably normal hearing: the ear canal must be open, not blocked by scar tissue; there must be an ear drum, either natural or man-made; there must be an air-filled pocket behind the ear drum; there must be a physical connection between the ear drum and the inner ear (usually, this connection is provided by the three tiny middle ear bones); finally, the inner ear must be in good working order. In your mom’s case, if the ONLY thing absent from this list is the connection from the ear drum to the inner ear, then I would say she has an excellent chance to recover much of her hearing. If the ear canal is partly blocked, if the ear drum is absent, or if there is no air space behind the ear drum, then there is a high likelihood that she would need a staged procedure (more than one operation.) If her inner ear is damaged (nerve deafness, known medically as "sensorineural hearing loss") and if this damage is extensive, then NO operation will restore her hearing.

This is, obviously, an optional operation. Well then, is it a good idea or a bad idea? Many things weigh into this decision. Even if the operation is technically feasible (as discussed in the last paragraph), it may still be a bad idea. Does she have other health problems that would make a general anesthetic risky? (In particular, serious problems with her heart or lungs would increase her risk during a general anesthetic.) How bothered is she by her hearing loss? Has she considered using a hearing aid in the bad ear? Would she still need to use a hearing aid on this ear, even after a successful operation?

If she is seriously considering having this operation, she should first talk to her doctor (her family practitioner or internist, not her ENT) about her level of risk for general anesthesia. If she has had her hearing tested by a licensed audiologist, she should consider discussing the operation with him/her. (Many ENTs train one of their office personnel to administer hearing tests. Audiologists have had a great deal more training, and most would be competent to comment on the possible appropriateness of surgery.) Finally, a second opinion from another ENT may be worthwhile.

 

Back to The Question and Answer Page

	More information available on other diseases of the ears, nose and throat!
	Click here if you have questions, comments or criticisms for Dr. Hoffman.

Copyright (c) 1998, 1999, Douglas Hoffman, all rights reserved. Reproduction in whole or part without permission is prohibited.