Tinnitus

views updated Jun 27 2018

Tinnitus

Definition

Tinnitus is a condition where the patient hears ringing, buzzing, or other sounds without an external cause. Patients may experience tinnitus in one or both ears or in the head.

Description

Tinnitus affects as many as 40 million adults in the United States. It is defined as either objective or subjective. In objective tinnitus, the doctor can hear the sounds as well as the patient. Objective tinnitus is typically caused by tumors, turbulent blood flow through malformed vessels, or by rhythmic muscular spasms. Most cases of tinnitus are subjective, which means that only the patient can hear the sounds.

Causes & symptoms

Subjective tinnitus is frequently associated with hearing loss and damage to the cochlea, or the inner ear. About 90% of patients have sensorineural hearing loss; 5% suffer from conductive hearing loss; and 5% have normal hearing.

The causes of subjective tinnitus include:

  • impacted ear wax
  • ear infections
  • hardening of the structures of the inner ear
  • hearing loss related to age
  • prolonged exposure to excessive noise
  • ototoxic medications, including aspirin, quinine, some diuretics, heavy metals, alcohol, and certain antibiotics
  • Ménière's syndrome
  • head trauma
  • systemic diseases, including syphilis, hypertension, anemia , or hypothyroidism
  • tumors of the ear

Diagnosis

Diagnosis of tinnitus includes a physical examination of the patient's head and neck. The doctor will use an instrument called an otoscope to examine the ears for wax, infection, or structural changes. He or she will also use a stethoscope to listen to the blood vessels in the neck.

The patient's doctor may also refer him or her to an audiologist, who is a health care professional trained to perform diagnostic testing of hearing problems.

In some cases, tinnitus is a symptom of temporomandibular joint disorder , or TMJ, which is caused by dysfunction of the temporomandibular joint in the jaw. The muscles and nerves in the jaw are located very close to the nerves that control hearing, which is why TMJ can cause tinnitus. Patients with tinnitus may be referred to a dentist or orthodontist for assessment of their jaw muscles or a misaligned bite.

Additional tests may include the following:

Tuning fork tests

The Rinne and Weber tests are commonly used to evaluate the type and severity of hearing loss. In the Weber test, the doctor holds a tuning fork against the patient's forehead or front teeth. If the hearing loss is sensorineural, the sound radiates to the ear with better hearing; if the hearing loss is conductive, the sound will be louder in the damaged ear. In the Rinne test, the tuning fork is placed alternately on the mastoid bone, which is behind the ear, and then in front of the ear. In conductive hearing loss, bone conduction (BC) is greater than air conduction (AC). In sensorineural hearing loss, AC is greater than BC.

Diagnostic imaging

Magnetic resonance angiography or venography (MRA and MRV) can be used to evaluate malformations of the blood vessels. Computed tomography scans (CT scans) or magnetic resonance imaging scans (MRIs) can be used to locate tumors or abnormalities of the brain stem.

Blood tests

The doctor may order a complete blood count (CBC) with specific antibody tests to rule out syphilis or immune system disorders.

Treatment

Dietary adjustments, including the elimination of coffee and other stimulants, may be useful in treating tinnitus. In addition, reducing the amount of fat and cholesterol in the diet can help improve blood circulation to the ears. Nutritional supplementation with vitamin C, vitamin E , B vitamins, calcium, magnesium, potassium , and essential fatty acids is also recommended.

In particular, zinc supplements have been recommended for patients diagnosed with tinnitus. A recent Turkish study has confirmed that older people whose diets have been deficient in zinc may benefit from supplements of this mineral as a treatment for tinnitus, but that younger patients eating well-balanced diets do not find that their symptoms improve when they take zinc supplements. The American Tinnitus Association comments that zinc supplements " generally carry little risk to health and some people find them helpful."

Gingko biloba, an herbal extract, has been shown to decrease tinnitus symptoms in controlled animal studies and may be helpful in treating humans, since it is believed to enhance circulation to the brain in situations where reduced circulation is the cause. Individuals taking such blood thinners as coumadin or heparin should not take Ginkgo biloba, as the herb can interfere with platelet activating factor, the chemical that enables blood to clot.

Acupuncture treatments may help decrease the level of tinnitus sounds the patient hears, and constitutional homeopathic treatment may also be effective. Some Chinese herbal treatments can be effective, as well.

Tinnitus Retraining Therapy, or TRT, has been successful in treating some subjective tinnitus patients. This therapy is based on the assumption that the severity of tinnitus is determined not by the patient's auditory system, but by the parts of the brain that control emotion (the limbic system) and body functions (autonomic nervous system). TRT focuses on habituating the patient to his or her tinnitus, retraining the brain to, in effect, "become used to" the tinnitus so that it does not perceive it as an annoyance.

Allopathic treatment

Some cases of tinnitus can be treated by removal of the underlying cause. These include surgical treatment of impacted ear wax, tumors, head injuries, or malformed blood vessels; discontinuance of ototoxic medications; and antibiotic treatment of infections.

Patients whose tinnitus is related to TMJ usually experience improvement in or complete disappearance of the tinnitus when the dental problem is corrected.

Subjective tinnitus, especially that associated with age-related hearing loss, can be treated with hearing aids , noise generators or other masking devices, biofeedback , antidepressant medications, or lifestyle modifications.

One mainstream form of psychotherapy that is recommended to patients with tinnitus is cognitive-behavioral therapy, or CBT. CBT works by changing the patient's emotional reaction to the tinnitus. The patient keeps a symptom diary and works on an individual basis with a counselor to identify negative thought patterns and behaviors related to the tinnitus and then changes them. The latest innovation in CBT for tinnitus is therapy via the Internet. According to a 2002 study by a group of Swedish researchers, 31% of patients who participated in a CBT program via the Internet reported significant relief from tinnitus at 1-year follow-up.

Expected results

The prognosis depends on the cause of the tinnitus and the patient's emotional response. Most patients with subjective tinnitus do not find it seriously disturbing, but about 5% have strong negative feelings. These patients are frequently helped by instruction in relaxation techniques.

Studies indicate that CBT is most effective as a treatment for tinnitus when it is combined with masking techniques or medication.

Prevention

One preventive measure is to wear earplugs when operating loud machinery or spending extended periods in such noisy environments as rock concerts. Prolonged exposure to noises of 90 decibels (about as loud as a running blender) or higher can cause permanent hearing loss and tinnitus. In some cases a change of occupation may be advisable; a recent British study found that as many as 266,000 men and 84,000 women in the United Kingdom between the ages of 35 and 64 suffer from tinnitus resulting from work-related noise.

More detailed information and advice on dealing with tinnitus associated with noise-induced hearing loss is available from the National Institute on Deafness and Communication Disorders (NIDCD), listed under Resources below.

Resources

BOOKS

House, John W. "Tinnitus." In Conn's Current Therapy, edited by Robert E. Rakel. Philadelphia: W. B. Saunders, 1998.

Jackler, Robert K., and Michael J. Kaplan. "Ear, Nose, & Throat." In Current Medical Diagnosis & Treatment 1998, edited by Lawrence M. Tierney, Stephen J. McPhee, and Maxine Papadakis. Stamford, CT: Appleton & Lange, 1997.

Pelletier, Kenneth R., MD. The Best Alternative Medicine, Part II, "CAM Therapies for Specific Conditions: Tinnitus." New York: Simon & Schuster, 2002.

"Tinnitus." Section 7, Chapter 82 in The Merck Manual of Diagnosis and Therapy, edited by Mark H. Beers, MD, and Robert Berkow, MD. Whitehouse Station, NJ: Merck Research Laboratories, 2001.

PERIODICALS

Andersson, G., T. Stromgren, L. Strom, and L. Lyttkens. "Randomized Controlled Trial of Internet-Based Cognitive Behavior Therapy for Distress Associated with Tinnitus." Psychosomatic Medicine 64 (September-October 2002): 810816.

Delb, W., R. D'Amelio, C. J. Boisten, and P. K. Plinkert. "Evaluation of the Tinnitus Retraining Therapy as Combined with a Cognitive Behavioral Group Therapy" [in German] HNO 50 (November 2002): 9971004.

Henry, J. A., M. M. Jastreboff, P. J. Jastreboff, et al. "Assessment of Patients for Treatment with Tinnitus Retraining Therapy." Journal of the American Academy of Audiology 13 (November-December 2002): 523544.

Jastreboff, P.J., W.C. Gray, and S.L. Gold. "Neurophysiological Approach to Tinnitus Patients." American Journal of Otology 17 (1996): 236240.

Palmer, K. T., M. J. Griffin, H. E. Syddall, et al. "Occupational Exposure to Noise and the Attributable Burden of Hearing Difficulties in Great Britain." Occupational and Environmental Medicine 59 (September 2002): 634639.

Schechter, M. A., and J. A. Henry. "Assessment and Treatment of Tinnitus Patients using a 'Masking Approach.'" Journal of the American Academy of Audiology 13 (November-December 2002): 545558.

Yetiser, S., F. Tosun, B. Satar, et al. "The Role of Zinc in Management of Tinnitus." Auris Nasus Larynx 29 (October 2002): 329333.

ORGANIZATIONS

American Academy of Audiology. 11730 Plaza America Drive, Suite 300, Reston, VA 20190. (703) 790-8466. <www.audiology.org>.

American Tinnitus Association. P.O. Box 5, Portland, Oregon 97207-0005. (800) 634-8978 or (503) 248-9985. <www.ata.org>.

Better Hearing Institute. 515 King Street, Suite 420, Alexandria, VA 22314. (703) 684-3391.

National Institute on Deafness and Other Communication Disorders (NIDCD), National Institutes of Health. 31 Center Drive, MSC 2320. Bethesda, MD 20892-2320. <www.nidcd.nih.gov>.

Vestibular Disorders Association (VEDA). PO Box 4467, Portland, OR 97208-4467. (800) 837-8428. <www.vestibular.org>.

OTHER

National Institute on Deafness and Other Communication Disorders (NIDCD). Noise-Induced Hearing Loss. Bethesda, MD: NIDCD, 2002. NIH Publication No. 97-4233. <www.nidcd.nih.gov/health/hearing/noise/asp>.

Paula Ford-Martin

Rebecca J. Frey, PhD

KEY TERMS

Ménière's syndrome
A disease of the inner ear, marked by recurrent episodes of loss of balance (vertigo) and roaring in the ears lasting several hours. Its cause is unknown.

Tinnitus

views updated May 23 2018

Tinnitus

Definition

Tinnitus refers to abnormal sounds heard in one or both ears, including possible swishing, ringing, whistling, roaring or rushing that does not come from the outside environment.

Description

Tinnitus, sometimes called head noise, is not a condition in itself, but is usually a symptom of another condition. It can occur in one or both ears, originating from any part of the ear, including the outer, middle, or inner ear or the part of the brain that controls hearing. Tinnitus is not dangerous, but can be annoying and upsetting to those who experience it, primarily because it is constant and distracting, sometimes interfering with the ability to concentrate. The presence of other sounds in the environment may diminish the sensation of tinnitus, but as soon as it becomes quiet, the swishing, ringing, buzzing or roaring will continue. Some head noise is to be expected in any adult, although normal sounds from the environment typically cover head noises to a great extent. However, the presence of significant sound without an outside source exceeds normal head noises and becomes an irritant to the individual.

The inner ear contains thousand of tiny auditory cells that each carry an electrical charge. When microscopic hairs on the surface of each auditory cell move as sound waves pass over them, the cell will discharge an electrical signal through the auditory nerve and, though the ear does not actually “hear” the electrical signal, the brain interprets it as sound. The hairs on auditory cells can become bent or broken and may respond by moving eratically, simultaneously releasing random or steady electrical signals that the brain will again interpret as noise. Although this mechanism is understood, it is not understood if it is the specific trigger for tinnitus.

Demographics

Tinnitus or head noise is common, particularly in adults over age 60 who have begun to experience age-related hearing loss (presbyacusis). One third of all adults report having tinnitus for some period during their lifetime. The prevalence of tinnitus has been estimated to be as low as 7.9 million and as high as 37 million. The range varies because millions of individuals worldwide experience tinnitus and report it, while millions of cases are believed to go unreported.

QUESTIONS TO ASK YOUR DOCTOR

  • Is the noise in my ears caused by nerve damage or by any of the medications I've taken?
  • Can I expect the tinnitus to diminish or go away entirely at some point?
  • What can I do to diminish the sound or avoid hearing it?
  • Is my blood pressure a factor in producing ear noises?

Causes and symptoms

Tinnitus can occur as the result of fluid in the ear or in the tube (auditory tube or Eustachian tube) that runs from the space behind the ear (tympanic cavity) into the nose and throat (nasopharynx), or infection or diseases that affect the bones of the middle ear or the membrane called the ear drum (tympanic membrane). Injury to the inner ear can occur with trauma to the head or neck, resulting in tinnitus and hearing loss. The bones of the middle ear can become stiff (otosclerosis), which can cause tinnitus and associated hearing loss. High blood pressure can cause a sensation of rushing in the ear. Similarly, the build up of fatty deposits in blood vessels (atherosclerosis ) close to the middle and inner ear can cause more turbulent blood flow than normal in the narrowed vessels, allowing the beating of the heart to be heard. Meniere's syndrome, a disease that affects the inner ear, can cause tinnitus as well as disrupting normal balance. Prolonged use of aspirin or aspirin-containing drugs may lead to head noise. Tinnitus can also be caused by some type of damage to the tiny hearing nerve in the inner ear. Hearing nerve damage is common during aging and may be accompanied by tinnitus. An extremely loud noise or steady exposure to loud noise over a period of time can be the cause of nerve-related tinnitus and hearing can be damaged permanently as a result. In rare instances, tinnitus can be a sign of aneurysm or brain tumor. Build up of ear wax can aggravate tinnitus but is not believed to cause it.

The only symptom of tinnitus, the ringing, buzzing, roaring, hissing, whistling or swishing may be noticed suddenly and continue steadily, and can also be intermittent and gradually increase in frequency. Tinnitus can be accompanied by hearing loss.

KEY TERMS

Acoustic neuroma —A non-cancerous tumor caused by growth of abnormal cells on the auditory nerve that governs hearing.

Audiogram —Agraph-like tracing that records results of hearing tests performed with an audiometer.

Audiometer —An electrical device designed to measure hearing across a range of frequencies.

Auditory tube (eustachian tube) —A tube joining the tympanic cavity behind the ear to the nasopharynx.

Nasopharynx —The space above the roof of the mouth (soft palate) that opens into the nasal cavity and joins with the tympanic cavity behind the ear drum.

Otosclerosis —Changes in the bones of the ear (stapes) that result in their stiffness and immobility, leading to progressive deafness.

Presbyacusis —Age-related hearing loss as a result of losing the ability to discriminate between sounds.

Tympanic cavity —A mucus-membrane lined cavity behind the ear drum that connects with the auditory (Eustachian) tube.

Tympanic membrane —The ear drum, a thin but firm covering over the tympanic cavity that forms a barrier between the middle ear and the outer ear.

Diagnosis

The physician will take a medical history of previous illnesses, surgeries, injuries and medications, and conduct a physical examination to help determine the likely source of tinnitus. The doctor will want to know the intensity of the sound and if it is steady or pulsing, heard constantly or only heard at certain times, and if any hearing loss or problems with balance were noticed before the tinnitus began. A hearing test (audiogram) will be conducted using an audiometer that measures ability to hear different frequencies. Blood pressure and heart rate will also be part of the physical examination. A special computerized test, the auditory brain stem response (ABR), may be performed to evaluate hearing nerves and pathways in the brain. Diagnostic imaging such as computed tomography (CT) or magnetic resonance imaging (MRI) may be conducted to determine if a rare small tumor may be pressing on the auditory nerve (acoustic neuroma).

After examination and testing, the condition may be diagnosed as “subjective tinnitus” if some evidence of nerve damage is found and only the individual can hear sounds. However, if the doctor can hear sounds attributable to high blood pressure or exaggerated heart or blood vessel noise due to atherosclerosis, the condition will be described as “pulsatile tinnitus.”

Treatment

There is no standard treatment for tinnitus, especially if it is believed to be part of age-related hearing loss. The individual cause of tinnitus may help direct treatment, however. Reducing blood pressure and decreasing salt intake is sometimes helpful. Avoiding stimulants such as caffeine in coffee, tea and colas may diminish tinnitus. Focus on other sounds rather than the tinnitus, such as listening to soft music when relaxing or resting. Other “white noise” such as the ticking of a clock or whirring of a fan may help reduce the sound of tinnitus during sleeping hours. Reducing stress and anxiety generally can reduce the sensation of tinnitus. Avoiding aspirin or medications containing aspirin may relieve the tinnitus. Drugs such as tricyclic antidepressants (amitriptyline, nortriptyline), nervous system depressants (benzodiazepines ) and muscle relaxants (baclofen) are sometimes prescribed and are reported to have provided relief in some cases. A drug used in the treatment of alcoholism (acamprosate)) has relieved tinnitus in some individuals, and a migraine medication (gabapentin) showed positive Results in a clinical trial.

Prognosis

In most cases, tinnitus will diminish on its own or the individual will become accustomed to the sound and essentially not “hear” it any more. If nerve damage is involved, tinnitus may be a permanent condition that will need to be accepted.

Therapy

Acupuncture has been recommended for treating tinnitus and has shown positive Results in some individuals. Hypnosis has also worked for some people, though there is no scientific basis for the Results. Electrical stimulation, a physical therapy technique, has shown some positive Results as well, coordinating electrical activity of auditory cells.

Herbs and supplements that have been reported to help reduce tinnitus include:

  • Ginkgo to help encourage circulation and improve hearing loss and tinnitus related to changes in blood pressure
  • B vitamin complex to reduce ear pressure and encourage healing; includes niacin and thiamine that provide direct nutrition for nerves
  • Vitamin E to improve circulation and provide antioxidant activity

Prevention

Excessively loud noise such as firearms, industrial equipment noise, chain saws, power mowers, or high intensity music should be avoided. Ear plugs or ear muffs should be worn to protect the ears against exposure to steady loud noise. Individuals should refrain from putting objects into the ears, even Q-tips for cleaning the ear, because ear wax can be pushed against the ear drum in this way, causing or aggravating tinnitus. Blood pressure should be checked regularly in senior adults and blood pressure medication should be taken as prescribed.

Resources

PERIODICALS Heller AJ. “Classification and epidemiology of tinnitus.” Otolaryngology Clinics of North America 36(2); 2003.

OTHER

Cunha JP. “Tinnitus (Ringing and Other Ear Noises)” Medicine Net. 2008. Available at www.medicinenet.com. Accessed March 14, 2008.

“Tinnitus.” Mayo Foundation for Medical Education and Research. 2006. Mayo Clinic. www.mayoclinic.com/ health/tinnitus/DS00365. Accessed March 13, 2008.

ORGANIZATIONS

American Speech/Language Hearing Association, 2200 Research Boulevard, Rockville, MD, 20850-3289, 800-638-8255, [email protected], www.asha.org.

American Tinnitus Association (ATA), PO Box 5, Portland, OR, 97207, www.ata.org.

L. Lee Culvert

Tinnitus

views updated May 18 2018

Tinnitus

Definition

Tinnitus is hearing ringing, buzzing, or other sounds without an external cause. Patients may experience tinnitus in one or both ears or in the head.

Description

Tinnitus affects as many as 40 million adults in the United States. It is defined as either objective or subjective. In objective tinnitus, the doctor can hear the sounds, as well as the patient. Objective tinnitus is typically caused by tumors, turbulent blood flow through malformed vessels, or by rhythmic muscular spasms. Most cases of tinnitus are subjective, which means that only the patient can hear the sounds.

Causes and symptoms

Subjective tinnitus is frequently associated with hearing loss. About 90% of patients have sensorineural hearing loss ; 5% suffer from conductive hearing loss; 5% have normal hearing. The causes of subjective tinnitus include:

  • impacted ear wax
  • ear infections
  • hardening of the structures of the inner ear
  • hearing loss related to age or excessive noise
  • ototoxic medications, including aspirin, quinine, some diuretics, heavy metals, alcohol, and certain antibiotics
  • meniere's syndrome
  • head trauma
  • systemic diseases, including syphilis, hypertension, anemia, or hypothyroidism
  • tumors of the ear

Diagnosis

Diagnosis of tinnitus includes a physical examination of the patient's head and neck. The doctor will use an otoscope to examine the ears for wax, infection, or structural changes. He or she will also use a stethoscope to listen to the blood vessels in the neck. Additional tests may include the following:

Tuning fork tests

The Rinne and Weber tests are commonly used to evaluate the type and severity of hearing loss. In the Weber test, the doctor holds a tuning fork against the patient's forehead or front teeth. If the hearing loss is sensorineural, the sound radiates to the ear with better hearing; if the hearing loss is conductive, the sound will be louder in the damaged ear. In the Rinne test, the tuning fork is placed alternately on the mastoid bone (behind the ear) and in front of the ear. In conductive hearing loss, bone conduction (BC) is greater than air conduction (AC). In sensorineural hearing loss, AC is greater than BC.

Diagnostic imaging

Magnetic resonance angiography or venography (MRA and MRV) can be used to evaluate malformations of the blood vessels. Computed tomography scans (CT scans) or magnetic resonance imaging scans (MRIs) can be used to locate tumors or abnormalities of the brain stem.

Blood tests

The doctor may order a complete blood count (CBC) with specific antibody tests to rule out syphilis or immune system disorders.

Treatment

Some cases of tinnitus can be treated by removal of the underlying cause. These include surgical treatment of impacted ear wax, tumors, head injuries, or malformed blood vessels; discontinuance of ototoxic medications; and antibiotic treatment of infections.

Subjective tinnitus, especially that associated with age-related hearing loss, can be treated with hearing aids, noise generators or other masking devices, biofeedback, antidepressant medications, or lifestyle modifications (elimination of smoking, coffee, and aspirin).

Alternative treatment

A variety of alternative therapies may be helpful in the treatment of tinnitus. Dietary adjustments, including the elimination of coffee and other stimulants, may be useful, since stimulants can make tinnitus worse. In addition, reducing the amount of fat and cholesterol in the diet can help improve blood circulation to the ears. Nutritional supplementation with vitamin C, vitamin E, B vitamins, calcium, magnesium, potassium, and essential fatty acids is also recommended. Gingko (Gingko biloba ) is often suggested, since it is believed to enhance circulation to the brain. Acupuncture treatments may help decrease the level of tinnitus sounds the patient hears, and constitutional homeopathic treatment may also be effective.

Prognosis

The prognosis depends on the cause of the tinnitus and the patient's emotional response. Most patients with subjective tinnitus do not find it seriously disturbing, but about 5% have strong negative feelings. These patients are frequently helped by instruction in relaxation techniques.

Resources

BOOKS

Jackler, Robert K., and Michael J. Kaplan. "Ear, Nose, & Throat." In Current Medical Diagnosis and Treatment, 1998, edited by StephenMcPhee, et al., 37th ed. Stamford: Appleton & Lange, 1997.

KEY TERMS

Conductive hearing loss Hearing loss caused by loss of function in the external or middle ear.

Meniere's syndrome A disease of the inner ear, marked by recurrent episodes of loss of balance (vertigo) and roaring in the ears lasting several hours. Its cause is unknown.

Ototoxic Damaging to the nerves controlling the senses of hearing and balance.

Sensorineural hearing loss Hearing loss caused by damage to the nerves or parts of the inner ear governing the sense of hearing.

tinnitus

views updated Jun 11 2018

tinnitus refers to the sensation of sound, most often a high-pitched, noisy whistle, in one or both ears in the absence of external stimulation. Like pain, tinnitus is a very subjective phenomenon, and descriptions by sufferers tend to be in terms of a familiar sound such as the roar of the ocean or the ringing of bells. Nearly everyone experiences a mild and transient form of tinnitus. Estimates of the incidence of more severe forms vary, but around 10–14% of adults complain of tinnitus that is either prolonged or present for much of the time, and 0.5% are so affected as to have difficulty in leading a normal life.

The first written record of tinnitus appears to date back to ancient Egyptian medical documents. There are several references in Babylonian medicine to the ‘singing ear’ or the ‘whispering ear’, for which incantation of charms was advocated. Descriptions of noises in the ear and their possible causes were placed on a more scientific footing through the works of the Greek scholar Hippocrates in the fourth and fifth centuries bc and the term tinnitus originates from ancient Rome. Over the subsequent centuries, different types of tinnitus were recognized and described more completely. However, tinnitus remains one of the least understood hearing conditions, for which there is still, in many cases, no specific cure.

Many sounds are generated within the head as a result of muscular activity and by blood rushing through the cranial vessels. However, we are rarely aware of these sounds because the cochlea is shielded by the hard temporal bone. Although people with apparently normal hearing do experience tinnitus, it usually accompanies some form of hearing loss. Indeed, most people who complain to their general practitioners of deafness will also have tinnitus. Although it is often associated with disorders of the ear itself, including blockage of the ear canal by wax, otosclerosis, and Menière's disease, it is now apparent that neural activity within the brain may be a more important factor. The discovery in the late 1970s that the ear produces sounds that can be detected in the ear canal suggested a possible link between tinnitus and the activity of outer hair cells in the cochlea. However, because drugs such as aspirin both eliminate these emissions and induce tinnitus, this seems to provide an explanation in only a few cases. Moreover, tinnitus is often found in people with severe sensorineural hearing loss or following physical damage to the inner ear, which would argue against a cochlear origin for the condition.

Because of its subjective nature and the paucity of external signs associated with tinnitus, the development of animal models has been problematic. Nevertheless, studies in animals have shown that high doses of aspirin give rise to increased spontaneous activity both in the auditory nerve fibres that leave the inner ear and in the auditory midbrain. We do not yet know the mechanisms underlying central tinnitus or even which areas of the auditory pathway are responsible, but it is possible that a change in the level of inhibitory activity may be involved.

Early remedies for tinnitus usually involved the administration, either orally or into the ear canal, of a variety of substances ranging from oils to ox urine. It was observed in ancient Greece that external noise could mask buzzing in the ears and this was used therapeutically in the nineteenth century. Unless the patient is completely deaf, noise generators are still useful today as a means of providing temporary relief. By amplifying speech or environmental noise, hearing aids can also be effective in many cases. It was claimed at the beginning of the nineteenth century that electrical stimulation of the ear could be used to treat tinnitus. In a similar vein, tinnitus is often reduced after profoundly deaf patients are fitted with a cochlear implant in which sounds are transduced into electrical signals that are delivered to electrodes inserted into the cochlea of the inner ear.

In a small minority of cases tinnitus may be alleviated if the cause of the hearing loss can be treated by surgical or medical means. Because tinnitus is aggravated by stress or fatigue, the most successful treatment involves psychological counselling or some form of relaxation therapy, often in conjunction with devices that use external noise to mask the sounds that are generated within the head.

Andrew J. King

Bibliography

Shulman, A.,, Aran, J.- M.,, Feldmann, H.,, Tonndorf, J.,, and and Vernon, J. A. (1991). Tinnitus: diagnosis/treatment. Lea and Febiger, Philadelphia.
Vesterager, V. (1997). Tinnitus — investigation and management. British Medical Journal, 314, 728–31.


See also deafness; hearing; hearing aid.

Tinnitus

views updated Jun 11 2018

Tinnitus

What Is Tinnitus?

What Causes Tinnitus?

What Can a Doctor Do?

Tinnitus (ti-NY-tus) is the sense of ringing, whistling, or similar noise in the ear even when there is no external sound.

KEYWORDS

for searching the Internet and other reference sources

Auditory disorders

What Is Tinnitus?

Tinnitus is a mysterious disorder that affects as many as 50 million Americans. The sound that people with tinnitus hear is often described as a ringing, but it also can resemble whistles, sizzles, clicks, roars, or other sounds too complex to describe easily. Some people experience the noise only at certain times or notice it only when it is quiet, such as at bedtime. Others, however, live with a constant unpleasant sound.

The noise can be high-pitched like a babys whine or low like a rumbling train. It might sound like a continuous tone or cycle in a rhythm, often in time with the heartbeat.

What Causes Tinnitus?

Tinnitus is usually a symptom of other problems, such as too much ear-wax or an ear or nasal infection. Other causes include cardiovascular disease, tumors, jaw misalignment, anemia, and neck and head injuries. Certain medicines, such as aspirin and some antibiotics, as well as carbon monoxide and alcohol, can also cause tinnitus. Long-term exposure to loud sounds like a jet plane or loud music can lead to tinnitus.

What Can a Doctor Do?

The first thing a doctor will do is look for the cause. If it is something that can be corrected, such as removing earwax or treating an infection, the tinnitus usually will go away.

Some people must find ways to live with tinnitus. Hearing aids are a common way to help, if the cause is related to hearing loss. Sometimes the person uses a device like a hearing aid that covers the tinnitus with another sound that is less noticeable or less disturbing.

See also

Vertigo

tinnitus

views updated May 29 2018

tinnitus (ti-ny-tŭs) n. the sensation of sounds in the ears, head, or around the head in the absence of an external sound source. It can occur with any form of hearing loss or with normal hearing and is thought to be due to a misinterpretation of signals in the central auditory pathways in the brain. t. retraining therapy (TRT) a unified method of treating tinnitus, including explanation, counselling, cognitive behavioural therapy, relaxation techniques, and sound therapy (see white noise instrument).

tinnitus

views updated Jun 11 2018

tin·ni·tus / ˈtinitəs; tiˈnī-/ • n. Med. ringing or buzzing in the ears.

tinnitus

views updated Jun 08 2018

tinnitus (path.) ringing in the ears. XIX. — L. tinnītus, f. tinnīre ring, tinkle, of imit. orig.