Tinnitus is an abnormal perception of a sound which is reported by patients that is unrelated to an external source of stimulation. Tinnitus is a very common disorder. It may be intermittent, constant or fluctuant, mild or severe and may vary from a low roaring sensation to a high pitched type of sound. It may or may not be associated with a hearing loss. It is also classified further into subjective tinnitus (a noise perceived by the patient alone) or objective (a noise perceived by the patient as well as by another listener). Subjective tinnitus is common; however, objective tinnitus is relatively uncommon. The location of tinnitus may be in the ear(s) and/or in the head.

Tinnitus is a symptom much like a headache, pain, temperature, hearing loss, or vertigo. With tinnitus, the reported distress is usually subjective and difficult to record and appreciate by others.

The quality of tinnitus refers to the description by the patient of the tinnitus: it may be a ringing, buzzing, cricket, ocean, etc., type sound. The quality may be multiple sounds or a singular sound.

Tinnitus may be produced in one or more locations called its site of lesion. The cause of tinnitus may be singular or multiple. A peripheral (i.e., auditory nerve, or cochlea) site of lesion includes dysfunction established within the auditory system that extends up to but not involving the brainstem. A central site of lesion refers to involvement of the central auditory pathways, beginning at the brainstem and involving other portions of the central nervous system.

Tinnitus is therefore, a symptom of neurotologic disease. It may occur with a hearing loss, vertigo or pressure symptoms in the ear or it may occur alone.

A complete cochleovestibular evaluation is necessary in all patients with severe disabling tinnitus. The test battery is used to attempt to establish the site of lesion and to rule out any significant pathology, which may require further treatment. There are many causes just related to the ear, which would result in tinnitus. Such things as simple ear wax in the ear canal to other middle ear abnormalities may result in tinnitus. Otosclerosis (fixation of the stapes bone in the middle ear) can cause tinnitus as well as fluid in the middle ear. There are many other ear abnormalities which may cause tinnitus. A more common example would be Meniere’s disease. Sudden trauma to the inner ear such as exposure to excessively loud sounds may result in tinnitus. Tumors on the hearing nerve or other problems in the brainstem or central nervous system may also cause tinnitus. In addition, other vascular abnormalities in the skull or base of the skull may result in tinnitus.

Measurement of Tinnitus

Since tinnitus often has a high pitch, frequency judgements in this region normally are poor. Frequency discrimination up to approximately 16,000 Hz (which is the upper limit of hearing) is far less exacting than the middle frequency region. In addition, patients suffering from high-pitched tinnitus often have a high frequency hearing loss, which may impair their frequency discrimination. Therefore, test-retest reliability in matching the frequencies of audiometer tones to the pitch of tinnitus may be poor. An attempt is made, however, to do pitch matching and loudness-matching. In addition, an attempt may be made to determine the maskability of the tinnitus (which is unrelated to its loudness) and a determination of residual inhibition can be made (i.e. when tinnitus is temporarily reduced after a masking sound has been turned off. The reduction is termed "residual inhibition").

Function of the Normal Ear

The ear is divided into three parts: an external ear, a middle ear, and an inner ear. Each part performs an important function in the process of hearing.

The external ear consists of the auricle (pinna) and ear canal. These structures gather the sound and direct it down the ear canal towards the ear drum membrane.

The middle ear chamber lies between the external and the inner ear and consists of an eardrum membrane and three small ear bones (ossicles), maleus (hammer), incus (anvil), and stapes (stirrup). These structures transmit the sound vibration to the inner ear. In so doing they act as a transformer, converting the sound vibrations in the external ear canal into fluid waves in the inner ear.

The inner ear chamber contains the microscopic hearing and balance nerve endings (hair cell) bather in fluid. Fluid waves initiated by movement of the stapes bone stimulate the delicate hearing nerve endings which in turn transmit an electrical impulse to the brain where it is interpreted as sound.

Types of Hearing Impairment

The external ear and the middle ear conduct the transformed sound; the inner ear receives it. When there is some problem in the external or middle ear, a conductive hearing impairment occurs. When the trouble lies in the inner ear, a sensorineural or hair cell moss is the result. Difficulty in both the middle and inner ear results in a mixed (i.e., conductive and sensorineural) impairment.

Generally, most patients will not need any medical treatment for their tinnitus. For patients who are greatly bothered by tinnitus, they may use come masking techniques such as listening to a fan or radio, which would mask some of their tinnitus. In addition, other sound sources generators can be obtained and be adjusted to sound-like environmental sounds and this is effective in masking tinnitus. This generally is more advantageous if one is attempting to go to sleep and still use some masking device. A tinnitus masker is utilized in some select patients. It is a small electronic instrument built into a post-auricular hearing aid case (over the ear). It generates a noise which prevents the wearer from hearing his own head noise. It is based on the principle that most individuals with tinnitus can better tolerate outside noise than they can their inner head noise.

Biofeedback training is effective in reducing the tinnitus in some patients. It consists of exercises in hourly sessions in which the patient learns to control the various parts of the body and relax the muscles. When a patient is ale to accomplish this type of relaxation, tinnitus generally subsides. Most patients have express that the biofeedback offers them better coping skills.

Other measures to control tinnitus include making every attempt to avoid anxiety, as this will increase your tinnitus. You should make every attempt to obtain adequate rest and avoid over-fatigue because generally patients who are tired seem to notice their tinnitus more. The use of nerve stimulants is to be avoided. Therefore, excessive amounts of coffee and smoking should be avoided. Tinnitus will not cause you to go deaf and statistically, 50 percent of patients may express that their tinnitus with time decreases or is hardly perceptible.

Other medications have been utilized to suppress tinnitus. Some patients benefit with these drugs and others do not. Each patient has an individual response to medication, and what may work for one patient may not work for another. Some of these medications have been proven, however, to decrease the intensity of the tinnitus and make it much less noticeable to the patient. There is, however, no drug, which will remove tinnitus completely and permanently. Some drugs will also cause tinnitus. If you have tinnitus and are on medication, you should discuss the symptoms of tinnitus with your physician. In many instances, once the drug is discontinued the tinnitus will no longer be present.

Other Sources for tinnitus information
If you desire more information about tinnitus, you may contact the
American Tinnitus Association, P.O. Box 5, and Portland, Oregon 97207.