Hearing impairment, deafness or hearing loss refers to a partial or total reduction in the ability to hear. The factors that caused hearing impairment are not limited to age, noise, illness and physical trauma. The severity of the hearing impairment can be diagnosed, and it is measured in decibels. The symptoms may be mild, moderate, severe or profoundly.1 in 6 of the UK adult population is affected by hearing loss.
The diseases or circumstances that can cause deafness are:
● Excessive noise exposure
● Chicken pox
● Sickle cell disease
● Lyme disease
● Diabetes, as studies have shown that people with diabetes are more likely to have some kind of
● A treatment for tuberculosis (TB), streptomycin, that is believed to be a key risk factor
● Some cancers
● Teenagers exposed to second-hand smoke
● Damage to the eardrum or middle ear can cause hearing loss and deafness in a range of ways.
Types of hearing loss:
Most of the people lose some degree of their hearing as they reach 65 and older, one out of three people have some type of hearing impairment. There are three types of hearing loss which are as follows:
Sensorineural hearing loss:
This is the most common type of hearing loss. Patients may experience a lack of sensitivity of sound or clarity of sound. The condition results in gradual loss of the sound receptors and nerve endings. The main reason of sensorineural hearing loss is hair cell damage, which is caused by long-term exposure to loud noises or high frequency sounds.
Conductive hearing loss:
In this type of hearing loss the vibrations are not passing through outer ear to the inner ear, specifically the Chloe. The main cause is the obstruction in the outer or middle ear, infections and diseases of the middle ear. Total deafness is rarely occurs due to conductive hearing impairments, and properly fitted hearing aid and sometimes surgical correction usually provides benefit.
Mixed hearing loss:
It is the combination of both conductive and sensorineural hearing loss. It is caused by long-term ear infections which leads to damage both eardrum and the ossicles. Surgical intervention may restore hearing, but it is not always effective.
Some people are born deaf, while others suddenly become deaf due to an accident and illness. Symptoms progress gradually over time.
The following signs may indicate a hearing problem in newborn:
● The baby does not turn their head toward a noise, before the age of 4 months.
● The baby still has not uttered a single word, before the age of 12 months.
● The infant does not appear to be startled by a loud noise.
● The infant only seems to be aware of certain sounds.
● The child keeps on saying “what” or “pardon”.
● The child is behind others in oral communication at the same age.
● The utterances of the child are not clear.
Levels of hearing loss
The audiologists classified the hearing loss in the four levels which are as follows:
Mild hearing loss:
The quietest sounds you can hear with mild hearing loss are between 25 and 40 dB. If there is a lot of background noise then it is difficult for a person to understand the words other people are saying.
People with moderate hearing loss cannot hear sounds that are less than 40-75 dB. It is very hard for a person with moderate deafness to understand the normal speech without using a hearing aid.
Severe hearing loss:
In severe hearing loss it is almost impossible to understand a normal speech without using a hearing aid. The person can only hear a sound that is above 70-89 dB.
A person who cannot hear a sound below 90 dB has profound deafness. Using hearing aid is ineffective in this case and people rely on lip-reading, gesture and other visual cues.