Tinnitus

The ear has three parts: the external ear (or pinna and ear canal), the middle ear, and the inner ear. Each part of the ear has a role in hearing.

The external ear gathers sound waves and transmits them to the ear drum. The eardrum is a membrane between the outer and middle ear. The sounds waves produce vibrations of the eardrum which are then transmitted to the first bone of the middle ear, the malleus (hammer). The sound waves are amplified as they are passed from the eardrum and malleus to the next two bones of hearing, the incus (anvil) and stapes (stirrup).

Once the sound waves have reached the stapes sound has been converted from an air pressure wave to a mechanical force. The stapes rests on a thin membrane separating the middle ear from the fluid-filled inner ear. As the stapes vibrates, sound waves are transformed into fluid waves in the inner ear.

The inner ear contains fragile membranes, hair cells and nerve endings. The fluid waves and movement of the membranes stimulate the hair cells, which then activate the nerve endings. Finally, the electrical signal of hearing travels along the cochlear (hearing) nerve to the brain and the sound is “heard.”

Most tinnitus is heard only by the patient. There are many potential causes of this type of tinnitus. The inner ear, hearing nerve, and brain are very delicate and may be injured by one or more of several different mechanisms including age, genetic and hereditary disease, infection, allergy, inflammation, tumors, metabolic problems such as diabetes or low- or high-thyroid, loud noise, prescription and over-the-counter medications, nicotine, and -last but not at all least- stress and fatigue.

Most people with tinnitus are not bothered by it. But for the 20% that are, it can be significantly disruptive to one’s work and family life. Because tinnitus can stimulate the centers of the brain responsible for emotion, some patients experience significant anxiety, depression, irritability and other strong emotional responses. The hearing system and emotion centers of the brain are intimately linked to the autonomic nervous system. The autonomic nervous system controls all the functions of our body, and performs most functions automatically, beyond conscious control. Because it is closely linked to emotion center, certain emotions result in physical changes in the body; for example, anger can increase the rate of heartbeat. It is responsible for the "fight or flight" reaction, the reaction that prepares the body to react to danger. It is this response that makes the hairs stand up, pupils of the eye dilate, the respiratory rate increase, and blood drain out of the face as it is shunted to muscles of the arms and legs. The autonomic reaction to tinnitus often results in problems with sleep, inability to pay attention to issues other than tinnitus, a high level of reactiveness, and suppression of positive emotions.

Although the physician cannot “hear” the tinnitus there are tests which may help quantify the pitch and loudness of the tinnitus. A hearing test is also important during the evaluation. Hyperacusis is an abnormal sensitivity to normal every-day sounds that often accompanies tinnitus. It can also be measured.

Of course, the most important part of an evaluation for tinnitus is a thorough history and physical exam by an ENT or otologist. A hearing test is performed. Special tests such as blood tests, MRI, CT, and auditory brainstem response are sometimes needed.

There are many approaches for the treatment of tinnitus. If a metabolic, drug, infectious, or inflammatory cause is identified specific treatment can be initiated. This may include changing or eliminating medications, managing elevated blood sugars, and treatment with antibiotics, antivirals, and/or anti-inflammatories. If a tumor is found it may be treated with surgery or radiation, or it may be simply watched.

Most tinnitus is idiopathic, meaning a specific cause is not identified. Simple measures may significantly alleviate the tinnitus:

• Avoid loud sound
• Eliminate nicotine and caffeine
• Avoid stressful situations
• Rest
• Get at least 8 hours of uninterrupted sleep every night
• Avoid too much quiet - use a fan, noise maker (ocean waves, birds, rain sounds) or quiet radio music at night to mask the irritating tinnitus as you are trying to sleep. During the day, you may find yourself less bothered by the tinnitus if your mind and body are engaged in activities and there are other sounds in the room for your brain to listen to.
• Avoid focusing on the tinnitus by frequently discussing it with your family

Cases which do not respond to these basic measures may be treated by a physician including:

• Stress reduction
• Relaxation techniques including massage and acupuncture
• Treatment for depression and anxiety
• Sleeping aids
• Hearing aids to improve underlying hearing loss
• Family support
• Professional support groups such as the American Tinnitus Association
• Tinnitus Retraining Therapy
• Gingko biloba - some patients find this herbal medication helpful, but the scientific data is inconclusive. Gingko biloba may increase the risk of bleeding.
• Sound therapy