Tinnitus is the medical term given to the condition when a person hears sounds which are not coming from an external source. In other words, it is a perception of sound, when no noise is actually present.
The sound may be heard in one or both ears. It could be loud or soft, in high or low pitch, and other people usually cannot hear it. The condition may develop slowly or can occur suddenly.
Tinnitus can be:
- Subjective: The noises in the head or the ear are heard only by the affected individual. Mostly they are auditory or neurological reactions to loss of hearing, and a majority of cases come under this category.
- Objective: This happens rarely, when sounds from the circulation of blood from blood vessels or structures near the ear can be heard by other people, and the affected person.
Tinnitus is described as a condition that begins in the ear and continues in the brain, and is quite common, especially among older people. It may be a sign of an underlying medical condition. Tinnitus can disrupt the daily lives of affected people, who may find it difficult to concentrate or sleep. It could result in anger, severe frustration, or even depression.
The symptoms
Tinnitus is not a disorder by itself. It is more likely a symptom suggesting something wrong in the auditory apparatus. It could be within the ear, the nerve that connects the inner ear to the brain, or in the part of the brain that processes sound.
- The most common complaint is ‘’ringing in the ears’’. Other sounds have also been described such as buzzing, clicking, or a hissing sound. It may sound similar to music or even singing.
- Pulsatile tinnitus – This is a type of tinnitus in which people hear sounds that are in sync with their pulse.
- Some people complain that the sounds come and go, while others say they hear them all the time. In some people tinnitus disappears gradually, while in others, the body gets used to it.
- In some, it affects their hearing, and in others, it makes them sensitive to sound – a condition called hyperacusis.
Causes
The exact reason for tinnitus is not known, only that it is often accompanied by varying degrees of hearing loss. Such cases are usually due to inner ear damage.
The inner ear consists of a coiled, spiral tube called the cochlea and the auditory nerve.
The most common cause of tinnitus is damage to the hair cells in the cochlea. These cells help to transform sound waves into signals that the brain receives. If the brain cannot receive certain sounds, it starts to process other sounds (in the same frequency) to compensate for the loss of signals.
The cochlea:
- can undergo age-related wear and tear (presbycusis), usually involving both ears.
- can be damaged by repeated exposure to excessively loud noise, for instance, with factory workers, musicians, and construction workers. Such people tend to lose hearing in one ear typically, and the loss involves the same frequency of the triggering noise.
Some of the other known conditions associated with tinnitus are:
- Infections in the middle ear and sinus regions.
- Build-up of ear wax, or accumulation of fluid due to infection in the middle ear.
- A perforated eardrum.
- The temporo mandibular joint is on either side near the ears. It connects the lower jaw to the skull. Damage to muscles or ligaments of the joint causes pain and sounds that can also lead to tinnitus.
- Meniere’s disease which is associated with hearing loss and vertigo (a sensation of spinning)
- Otosclerosis where hearing loss is caused by abnormal bone growth in the middle ear.
- Tumours of the brain, thyroid disease, or hormonal changes in women.
- As a side effect of certain medications when they are started, and certain others when they are stopped. They include the pain killer category called NSAIDs or non-steroidal anti-inflammatory drugs; certain antibiotics; antimalarial drugs and certain cancer drugs.
A few rare causes of tinnitus:
- Head injury or exposure to a sudden loud noise such as an explosion or gunfire.
- Anaemia, high blood pressure, diabetes, or thyroid disease.
- Atherosclerosis, in which there is a narrowing of blood vessels (arteries).
Diagnosis
The symptoms have to be described in detail because it is important to know if the sound is continuous, if it is subjective or not, and whether one or both ears are affected. A complete examination of the ear is done to check for earwax or any infection.
Hearing tests
A complete audiological evaluation is done because hearing loss is often a cause of tinnitus. These are some of the hearing tests:
Subjective tests
- Speech recognition test or speech audiometry measures how well a person can hear and repeat particular words.
- Audiogram measures a person’s hearing across different volumes and frequencies.
Objective tests
- Tympanogram measures the functioning of the middle ear.
- Acoustic reflex testing shows how the middle ear muscles respond to loud noise.
- Otoacoustic emission testing uses sensitive microphones to measure the movement of hair cells inside the inner ear.
Other tests such as magnetic resonance imaging may be done to determine the specific reasons for the condition.
Treatment
There is no permanent solution to tinnitus, but any underlying medical condition that is causing it can be treated. For instance, earwax can be removed; any infection can be treated with antibiotics.
In situations where there is no specific cause, tinnitus is usually managed with a variety of procedures.
- Treatment for hearing loss: It is believed that the brain compensates for hearing loss by processing sound differently. Certain frequencies of sound that are no longer received by the brain cause it to adapt and change. Such situations can be improved with hearing aids.
- Sound therapy helps to distract the individual from the sounds of tinnitus. Special sound generators produce continuous soothing sounds that can be fitted in the ear.
- Counselling and cognitive behavioural therapy can reduce anxiety by changing one’s thoughts and behaviour. People learn to accept and cope with the condition.
- Self-help techniques involve yoga, deep breathing, listening to calm music, and engaging in hobbies to serve as a distraction from tinnitus.
Sources:
1.https://www.nhs.uk/conditions/tinnitus/
2.https://www.nidcd.nih.gov/health/tinnitus
3.https://www.nhsinform.scot/illnesses-and-conditions/ears-nose-and-throat/tinnitus
