Tinnitus

Overview

Tinnitus is the perception of noise or ringing in the ears, commonly caused by inner ear hair cell damage. Tiny, delicate hairs in your inner ear move in relation to the pressure of sound waves. This triggers cells to release an electrical signal through a nerve from your ear (auditory nerve) to your brain. Your brain interprets these signals as sound. If the hairs inside your inner ear are bent or broken, they can "leak" random electrical impulses to your brain, causing tinnitus.

It is very common, affecting up to 1 in 5 people, and is not a diagnosis in itself, but is a symptom of an underlying condition. A common misconception is that there is no cure for tinnitus, but treating the underlying condition may make the tinnitus settle down in many people.

Having tinnitus is very unlikely to be a sign of anything serious, and often worrying about the tinnitus can in itself make it sound louder and more intrusive.

A specialist ENT doctor may be able to identify the underlying cause of your tinnitus, although in many cases, a treatable cause cannot be found. If there is a cause identified, the ENT doctor may be able to treat it for you, refer you on to a more appropriate specialist for treatment, or on to a specialist audiologist for advice about masking devices or tinnitus therapies.

Symptoms

Any type of tinnitus noise is possible, but these are common sounds:

• Ringing

• Buzzing

• Roaring

• Clicking

• Hissing

• Humming

It may be high or low pitch, may be constant or fluctuate, or may change in pitch or type. For some people, tinnitus can be so bad that it can interfere with concentration or sleep.

Most often, tinnitus is subjective (only you can hear it). This is usually caused by a problem in the outer, middle or inner ear, or the hearing nerves and pathways in the brain.

Less commonly, tinnitus is objective (can be heard by your doctor or other people). This is caused by an artery or vein problem, or occasionally by the muscles or bones in the middle ear

Common causes of tinnitus

In many people, tinnitus is caused by damage to the tiny nerve endings (hair cells) in the inner ear, which then send faulty electrical signals to the brain. These faulty signals are interpreted as sound by the brain, resulting in tinnitus. The commonest causes of this are:

• Age-related hearing loss. (Prebyacusis) Common over the age of 60, but may start earlier. Degeneration of the inner ear hair cells causes tinnitus.

• Noise-induced hearing loss. Prolonged exposure to loud sounds (eg industrial noise, power tools, and firearms), without appropriate ear protection, causes inner ear damage resulting in hearing loss and tinnitus. Loud music through headphones may also cause hearing loss if played loudly for long periods. Tinnitus caused by short-term exposure, such as attending a loud concert, usually goes away; both short- and long-term exposure to loud sound can cause permanent damage.

Other common causes are

• Earwax blockage. If wax completely blocks the ear canal, hearing loss and tinnitus may occur. This is usually easily treatable by your ENT specialist.

• Stiffening of the bones in your middle ear (otosclerosis) may affect your hearing and cause tinnitus. May run in families or come on during pregnancy.

Less common causes of tinnitus

Some causes of tinnitus are less common, including:

• Meniere's disease. This is caused by inner ear fluid pressure changes. Although usually patients get attacks of tinnitus, hearing loss, dizziniess, and fullness in the ear, tinnitus may be a sign of early Meniere’s.

• TMJ disorders. The jaw joint (temporomandibular joint) is right in front of your ear, and problems with it, often in people who clench or grind their teeth, may cause tinnitus.

• Head injuries or neck injuries. Many people with whiplash injuries experience tinnitus, hearing loss or dizziness. It will often settle as the neck problems settle. Head injuries can affect the inner or middle ear, hearing nerves or the part of the brain linked to hearing. Such injuries generally cause tinnitus in only one ear.

• Acoustic neuroma. This is a noncancerous (benign) tumour on the nerve of balance and hearing. Usually causes tinnitus in only one ear.

• Eustachian tube dysfunction. Either obstructive or patulous tube problems can be associated with tinnitus. See Eustachian Tube Dysfunction section for more details.

• Muscle spasms in the inner ear. Muscles behind the ear drum can go into spasm, causing tinnitus, hearing loss and a feeling of fullness in the ear. This may be for no reason, but can also be caused by neurologic diseases, including multiple sclerosis.

Circulatory problems linked to tinnitus

• High blood pressure can make tinnitus more noticeable. Usually in both ears. Important to see your GP if this is the case, to discuss other cardiovascular risk factors (high cholesterol, smoking, family history, diabetes)

• Atherosclerosis. Hardening of the large arteries that run near your inner ear reduces their ability to flex or expand with each heartbeat. This causes blood flow to become more forceful, making it easier for your ear to detect the beats. You can generally hear this type of tinnitus in both ears. Sometimes if one of the main arteries in the neck or head is very hardened and narrowed, or kinked, it causes turbulent blood flow, which may just be on one side.

• Head and neck tumours. A lump pressing on (or arising from) blood vessels in or near the ear can cause tinnitus and other symptoms.

• Turbulent blood flow. Narrowing or kinking in a neck artery (carotid artery) or vein in your neck (jugular vein) can cause turbulent, irregular blood flow, leading to tinnitus.

• Capillary malformations. (arteriovenous malformation (AVM)). These are abnormal connections between arteries and veins, and can cause turbulent blood flow, resulting in tinnitus, usually just in one ear.

Medications that can cause tinnitus

Tinnitus may be a side effect of one of your medications, which may stop if your doctor can find an alternative drug. It is important to note that although many medications have tinnitus listed as a side effect, often this actually affects less than 1 in 1000 of all people on that drug. In addition, some drugs that cause tinnitus are given for a serious condition where there is no alternative medication.

Common medicines that can cause tinnitus include:

• Antibiotics, particularly aminoglycosides (gentamicin, streptomycin). These are usually given intravenously for serious infections. Antiobiotic ear drops containing gentamicin are generally safe to give.

• Chemotherapy medications, including methotrexate, cisplatin, carboplatin, oxaliplatin

• Water tablets (diuretics), such as bumetanide or furosemide. Probably only cause permanent damage when used together with other ototoxic drugs

• Quinine medications used for malaria or other health conditions

• Certain antidepressants (selective serotonin reuptake inhibitors, SSRIs) which may worsen tinnitus in some people (eg citalopram, fluoxetine, sertraline)

• Aspirin, usually at very high doses, but some people are unusually sensitive and develop tinnitus at low doses 

In addition, some herbal supplements can cause tinnitus, as can nicotine and caffeine.

Risk factors

Anyone can experience tinnitus, but these factors may increase your risk:

• Loud noise exposure. 

• Age. 

• Sex. Men are more likely to experience tinnitus.

• Stress. Higher stress levels may result in tinnitus or worsen pre-existing tinnitus.

• Smoking. 

• Cardiovascular problems. High blood pressure, narrowed arteries.

Complications

Tinnitus can significantly affect quality of life. Although it affects people differently, if you have tinnitus, you may also experience:

• Fatigue

• Stress

• Sleep problems

• Trouble concentrating

• Memory problems

• Depression

• Anxiety and irritability

Treating these linked conditions may not affect tinnitus directly, but it can help you feel better.

Prevention

In many cases, tinnitus is the result of something that can't be prevented. However, some precautions can help prevent certain kinds of tinnitus.

• Use hearing protection. 

• Turn down the volume when listening to amplified music with no ear protection or listening to music at very high volume through headphones. Over the ear headphones may be better than ear buds, since you don’t have to have the volume so high to drown out ambient noise.

• Take care of your cardiovascular health. Regular exercise, eating right and taking other steps to keep your blood vessels healthy can help prevent tinnitus linked to blood vessel disorders.

Further information

The British Tinnitus Association website has lots of really useful information about tinnitus diagnosis and treatment.