Hearing loss is a disorder characterised by reduced ability to perceive sounds. The risk of developing hearing loss increases with aging. Based on the extent and development of the condition, hearing loss is categorised as sudden or gradual, partial or total, permanent or temporary. It may develop simultaneously in one or both ears.
Ability to hear is one of the most important senses that we humans have. Anatomically speaking, the ear is divided into 3 parts, the outer ear, the middle ear and the inner ear. Sound from external environment enters the ear through the ear canal and hits the ear drum. This causes the ear drum to vibrate, which gradually amplifies as it passes through the middle ear by the action of 3 tiny bones present in this region. The vibrations are then transformed into nerve impulses which travel to the brain and are interpreted as sounds.
Any disruption in the above mentioned process leads to hearing loss. Injury in the outer or middle ear leads to a condition called as conductive hearing loss. Damage to the inner ear, the 8th cranial nerve or the brain which helps in the production, transmission and interpretation of sound, leads to sensorineural hearing loss. With aging, development of sensorineural hearing loss is more common than conductive hearing loss.
Symptoms of Hearing Loss in Adults
Sudden hearing loss is noticed immediately by the patient where as in case of gradual hearing loss, the patient may not be aware of the symptoms. Affected individuals may have difficulty in understanding conversations and he or she may misunderstand what others say or ask them to repeat. They might be playing the television in a very high sound in order to hear. Some individuals are unable to hear the doorbell ring or phone ring. There may be other additional symptoms along with hearing loss such as:
- Tinnitus or ringing in one or both ears
- Fluid discharge or blood discharge from the ear canal
- Ear ache or severe tenderness in the ear canal
- Feeling of fullness or pressure build up inside the ears
- Equilibrium imbalance
- Nausea, headache, irritability etc.
Causes of Hearing Loss in Adults
The possible causes of hearing loss in adults are as follows:
- Aging as a Cause for Hearing Loss in Adults: Hearing loss is very common after the age of 60 years. This is also known as prebycusis. In these cases, usually both ears are affected. The affected individuals has difficulty in hearing high pitched sounds such as women’s voice, violins etc.; but they do not have difficulty hearing low pitched sounds such as men’s voices, bass guitar etc. necessarily. This occurs over a period of time and in most of the cases, the individual does not realize that he or she is experiencing hearing loss.
- Middle Ear Disorders as a Reason for Hearing Loss in Adults: Disorders in the middle ear can be caused by bacterial infection which in turn can lead to ear drum injury, fluid build-up in ears or damage to the bones of middle ear. These, if left untreated, can lead to diminished hearing or hearing loss over a period of time.
- Exposure to Loud Noise: Long term exposure to loud noise or sudden exposure to extremely loud noise can lead to destruction of the delicate cells present within the ears. This is a type of sensorineural hearing loss. It is commonly seen in individuals with a history of listening to loud music through ear phones or loud speakers.
- Otosclerosis: Otosclerosis is a type of conductive hearing loss caused by abnormal growth of middle ears bones. This disrupts the normal movement and function of these bones leading to hearing loss. This condition is commonly seen in individuals with known family history of otosclerosis.
- Acoustic Neuroma as a Reason for Hearing Loss in Adults: Acoustic neuroma is a type of non-cancerous tumor that grows on the 8th cranial nerve (which helps in conduction of signals between the ears and the brain). The symptoms include gradual loss of hearing with dizziness and equilibrium issues.
- Hearing Loss in Adults Due to Meniere’s disease: This condition is characterized by presence of excess fluid within the ear canal. This leads to dizziness, ringing in the ears, sensation of fullness in ears and hearing loss.
- Injury or Trauma: Hearing loss in adults can also occur due to injury or trauma to the ear drum. This can happen from inappropriate use of Q-tip, insertion of hair pins in the ear canals or injury from force of an explosion.
- Viral Infection: Viral infection can lead to sudden loss of hearing in adults or anyone for that matter. This is treated as a medical emergency and it usually occurs over a period of 3 days or less. It generally affects only one ear.
- Side Effect of Drugs: Certain medications (prescription drugs as well as over-the-counter drugs) can lead to hearing loss. These drugs include high dosage of aspirin, certain anti-biotics, anti-cancer medication used for chemotherapy, anti-malaria drugs etc.
- Other Causes of Hearing Loss in Adults: Other miscellaneous causes of hearing loss include cerumen impaction or excessive ear wax build up, acute infections etc.
Diagnosis of Hearing Loss in Adults
Diagnosis, treatment and management of hearing loss are done by an ENT specialist or an audiologist. A detailed case history is obtained followed by physical examination of the ears. History of recent exposure to loud music, infections, injury, and drug usage is obtained from the patient or the family members to reach a conclusion. A series of ear examination is done which includes the following:
- Physical examination of the ear canal with a lighted instrument• Conductive hearing loss test using a vibrating tuning fork placed on the bone behind the ear. This is also known as Rinne test.
- A test may be done by placing a vibrating tuning fork in the middle of the forehead to determine one sided hearing loss. This test is also known as Weber test.
- In some cases, the physician may use a hand held device to produce sounds of various intensities to check if the patient can hear them correctly. This is known as audioscopy testing.
Once hearing loss is diagnosed, he or she is referred to an audiologist, who will carry certain specific test to study his or her hearing sensitivity. This may also include tests to determine issues with the middle ear and eardrum’s ability to reflect sounds.
Treatment for Hearing Loss in Adults
Age related hearing loss in adults is often permanent and irreversible. In most of the cases, a hearing aid or an implant is recommended to improve communication. Hearing aid is a device which helps in amplification of external sounds electronically and it is generally effective in management of hearing loss in adults. A large variety of hearing aids are available in the market and can be purchased based on the requirement. Cochlear implants are artificial implants which help in translating sounds to electrical signals which are then carried to the brain. In some cases, treatment of the underlying issue helps in overcoming hearing loss. Surgical intervention may be considered in cases of otosclerosis, acoustic neuroma, ear drum damage etc.
Prevention of Hearing Loss in Adults
Certain precautionary measures can help in minimizing the risk of developing hearing loss in adults. These include the following:
- Wearing ear plugs or ear muffs when exposed to loud sound at work place or during other recreational activities.
- Avoid inserting cotton buds and other foreign objects in the ear canal.
- Wear protective helmet while riding a bike and wearing seatbelt while driving.
- Understanding possible side effects of new medications before starting them.
- Avoid listening to loud music particular through ear phones.
Hearing loss in adults could be a very difficult issue to manage or adjust initially. However, early diagnosis and intervention can help in proper management and improvement of the condition. Moreover, hearing loss in adults can be easily prevented by following the precautionary measures. Hearing loss could be difficult to adjust with and hence proper family support is required to cope with the situation.