I recently had surgery -- upper and lower mandibular advancement and septum straightening -- to improve a problem with obstructive sleep apnea. I sometimes now can hear my breathing and my own voice rather loudly in my right ear. I have been told by an ENT that I have a dysfunctional eustachian tube as a result of the trauma of surgery. I have been told that there is nothing medically that can be done to correct it. The problem diminishes when I lie down during the night and returns around midday. Is there anything that can be done?

W.M.

You do have dysfunctional eustachian tubes, but it's NOT what your ear, nose and throat doctor (ENT) thinks. If your ENT really understood what was happening, he would have told you to gain weight.
I'm not kidding. I suspect that you suffer from patulous eustachian tube dysfunction (PETD for short). This is very different from garden-variety eustachian-tube dysfunction -- the opposite problem, in fact. One of the common causes of PETD is weight loss. I suspect that you lost several pounds as a result of your jaw surgery, and that your symptoms were not present immediately after surgery but developed during the recovery period.

Eustachian tubes are tubes of muscle and cartilage that extend from the throat to the middle ears (the air pocket behind each eardrum). They are closed most of the time, and "pop open" occasionally to ventilate the middle ears. People with "ordinary" eustachian tube dysfunction have trouble opening their eustachian tubes. Hearing loss, when it occurs, is global -- EVERY sound is muted.

People with PETD have trouble because their eustachian tubes are open too often. Typically, PETD sufferers note distortion of their own voice. All other sounds are normal. It is not unusual for them to have a hard time explaining this symptom to a doctor (Patient: "Doctor, I can hear my own voice!" Doctor: "Well, of course you can hear your voice!") This symptom is so distinctive that it has earned a name: "autophony."

When a person speaks, most of the sound is conducted to the inner ear via the normal route (mouth to ear). A small amount of sound is transmitted directly to the inner ear by bone conduction (vibration of the skull). If your eustachian tube is patulous, sound can also reach the inner ear via the eustachian tube. This results in subjective distortion and/or loudness of your voice. All other sounds reach the inner ear via the normal route and are not distorted.

The timing of your symptoms is characteristic of PETD. Autophony improves when the patient is horizontal and worsens when the patient is vertical. When you are horizontal, some of the fluids that had pooled in your legs redistribute to your upper body and head. This "bulks up" the tissues surrounding the eustachian tubes, helping them to remain closed. Similarly, weight loss can lead to PETD because there are fat deposits surrounding the eustachian tubes. If this fat diminishes, the tubes may "flop open" from a lack of structural support.

So, to be perfectly blunt: Your problems are almost certainly NOT "a result of the trauma of surgery." If I sound a bit annoyed, it's because your ENT's statement was more than a little inflammatory. Some patients would take such a comment as an invitation to pursue a malpractice lawsuit against the previous surgeon.

What should you do about it? If I am right about the weight loss, and if you are gradually gaining weight, then your symptoms may resolve on their own. If your symptoms persist, it would be a good idea to see a doctor who can determine whether or not you have PETD. I would suggest you see an otologist (an ENT who has taken specialty training in the medical and surgical treatment of ear problems). If you do have PETD, a variety of treatments are available. These treatments have in common the creation of edema (swelling) of the eustachian-tube opening. Incidentally, when PETD is misdiagnosed as garden-variety eustachian-tube dysfunction, aggressive medical treatment can lead to a worsening of autophony.