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Progressive hearing loss is said to impact one in four people worldwide, but the good news is that timely medical intervention can avert deafness. Image Credit: Shutterstock

Dubai: For many years, Habib-Ur Rahman, 42, from Peshawar, Pakistan, working as a driver in a Dubai-based company, struggled with progressive hearing loss. But he didn’t give it much thought.

Habib-Ur Rahman

“It was only my left ear that was impacted, so I was managing until one day fluid started oozing out from that ear and a sharp pain. I went to the hospital, underwent many tests. Initially, they tried medication, but when that failed, in October 2020, I had to undergo a surgery for the perforations in my inner ear. By God’s grace, I no longer suffer from any pain. I can hear well too,” Rahman said.

Doctors in Dubai say there are many others like Rahman who complain of progressive hearing loss as a result of exposure to high decibels of noise. Progressive hearing loss is said to impact one in four people worldwide, but the good news is that timely medical intervention can avert deafness and even restore the sense of hearing in as many as 90 per cent people.

According to research carried out by a UAE-based hearing aids and solutions company, approximately four per cent of the people in the country suffered from progressive hearing loss in 2017, while the World Health Organisation (WHO) estimates that about three per cent of the population in the Gulf region suffer from mild-to-moderate hearing loss. On March 3, this year, on the occasion of World Hearing Day, WHO released its first world report on hearing loss, which cautioned that about 2.5 billion people worldwide are likely to suffer from moderate-to-severe hearing loss by 2050.

What is hearing loss?

Dr Prashant Sharma, senior otolaryngologist at Prime Hospital, explained: “When we experience a failure in picking up sounds in the normal range of conversation, we are said to be experiencing a hearing loss. We actually hear with our brain.”

Understanding the anatomy of the ear is essential to recognise the first signs of loss of hearing. Image Credit: Shutterstock

Understanding the anatomy of the ear is essential to recognise the first signs of loss of hearing.

Dr Prashant Sharma

Dr Sharma said, “Our ear has three chambers — the outer ear, the middle ear and the inner ear. The outer ear that consists of the outer ear structure receives external sound waves as vibrations and these waves travel through the ear or auditory canal to the middle ear. The middle ear contains the ear drum and the three ossicle bones — malleus, incus and stapes. The eardrum vibrates with the sound waves and transmits it through the bones to the inner ear. The waves travel to the inner ear, which contains the cochlea and the auditory nerve. The cochlea, that has a coiled shape, consists of many sensory cells, fine fibres and fluid. The sound vibrations move in a fluid-like manner through the auditory nerve, which transmits these waves in the form of nerve impulses to the brain, where the auditory cortex interprets the signals and redirects it to the ear and then we are able to respond to the audio signals. Rather, we ‘hear’ and make sense of the noise around us. All this happens in a fraction of a second.”

Kinds of hearing loss

Dr Maher Khalil, otorhinolaryngology expert from the NMC Royale Hospital, Dubai, said: “There are three categories of hearing loss: Conductive hearing loss, sensory-neural hearing loss and mixed hearing loss.”

Conductive hearing loss: Occurs with a malfunction in the outer and middle ear. This could happen with sudden impact to the ear, wax or fluid collection in the ear canal, damage to the eardrum with a high sound, virus or bacterial infection. The conduction of the sound waves to the auditory nerve is impacted and usually this is an acquired hearing loss, which can be corrected with early medical intervention.

Dr Maher Khalil

“If medicines fail, then surgery can help reverse the condition in most cases. Most of the hearing loss that adults experience and those that are not congenital can actually be addressed successfully with early intervention,” added Dr Khalil.

Sensory-neural hearing loss: “Usually due to a genetic deficiency, birth defect or syndrome (such as Down’s Syndrome), the neural pathways carrying the vibration to the brain are impacted. These can be corrected with early diagnosis and cochlear implant surgery,” explained Dr Khalil.

Mixed hearing loss: Occurs when there is a combination of conductive and sensory-neural loss.

Most common cause of hearing loss

Noise pollution is one of the main reasons behind progressive hearing loss in adults. In a recently-conducted study in the United States, it was found that one in four college students in the age group of 18-24 experienced partial hearing loss. “That is because most youngsters spend most of their waking hours with their head phones attached to their ears, constantly exposing themselves to auditory sensation higher than 85 decibels,” said Dr Sharma.

“When a human being is exposed to a sound louder than 100 decibels for a long period of time, he is likely to suffer conductive hearing loss. During a normal conversation, we are exposed to a sound level of 50-60 decibels. Listening to music continuously on headphones, where people cancel out other noises or in a cinema hall, they are exposed to sound as loud 70-100 decibels. While watching a rock concert or live fireworks display with loud crackers, we can be exposed to sound that is in the range of 140 decibels. Exposure to loud decibels of sound progressively impacts our sense of hearing,” he added.

Subjective and objective hearing loss

Hearing loss can also be classified as objective and subjective. People who suffer from recurrent middle-ear infections, damage to the tympanic membrane due to fungal, bacterial or viral infections, can suffer from ear pain or a ringing sensation in the ears. This is also called tinnitus, which can lead to objective hearing loss, and is temporary. However, when left unattended for a long time, it can turn into permanent partial hearing loss.

Dos and don’ts to protect sense of hearing:
* Go in for genetic counselling prior to marriage, especially in consanguine marriages, to avoid any chromosomal abnormalities that can lead to genetic hearing loss.
* Have an auditory examination to assess your newborn’s hearing.
* If the examination casts doubts on the hearing ability, conduct another detailed behavioural test once the child begins school. * If your child is diagnosed with moderate-to-severe hearing loss, consider a cochlear implant as early as possible.
* In adults, do not ignore ear pain or inner-ear discharge.
* Do not clean your ear with ear buds or sharp instruments. Seek the help of your ENT in case of excess wax. This could be discharge from an infected ear.
* While swimming, make sure to block your ear canal with proper ear blocks to prevent water entering and also to maintain optimum pressure in the ear canal.
* Pregnant mothers can undergo screening for TORCH syndrome to avoid hearing defects in their newborns. TORCH syndrome is an acronym for a group of conditions such as Toxyplasmosis, Other agents, Rubella, Cytomegalovirus and Herpes Simplex virus. All these conditions can actually pass through the placenta and can impact the hearing capacity of the foetus. Both pregnant mothers and neonatals are advised to undergo TORCH syndrome screening.
* A diet that is healthy and balanced, with large portions of fruit and raw vegetables and fibre, is advised to keep cholesterol under control and maintain a healthy heart. Blocked carotid artery can also create some pressure and block the sense of hearing.
* Undergo auditory assessments, at least once every year, in case you experience some hearing deficit and be prepared to go in for early intervention to avoid hearing loss.

Subjective hearing loss can occur in people who suffer from vascular blocks in the middle ear or tight carotid arteries due to blocks that can pressure the ear, causing tinnitus.

How hearing loss is treated

The traditional treatment for hearing loss for someone with moderate-to-profound partial hearing loss is a cochlear implant, which is implanting a neuro-prosthetic, electronic device in the inner ear to facilitate the transmission of sound waves to the brain. An external microphone in the outer ear behind the external ear helps capture the sound that travels to the implant and signals are sent via the implant to the brain to facilitate hearing.

The Auditory Brain-stem Implant (ABI) is an electronic hearing device, which is completely internal with no external microphone and is implanted in the brain stem via a brain surgery. It provides the sensation of sound waves to a partial-to-profoundly deaf person as it creates sound awareness. It is usually implanted in people with damaged auditory nerves.

The Piezo Electric membrane implant is still a subject of study and research, undertaken by Japanese audiologists. This device consists of a thin hair-like membrane, which, when implanted, can mimic the vibrations on the fine hair cells of the tympanic membrane and create electrical impulses in response to sound stimuli that can travel to the brain stem and be transmitted to the middle and external ear to facilitate hearing. Such membranes are relatively new devices and still undergoing tests.

Can hearing loss be prevented?

A WHO report pointed out that almost 60 per cent of hearing loss in children could be prevented through measures such as immunisation for prevention of rubella and meningitis, improved maternal and neonatal care and screening for and early management of otitis media — inflammatory diseases of the middle ear.

In adults, noise control, safe listening and surveillance of ototoxic medicines, together with good ear hygiene, can help maintain good hearing and reduce the potential for hearing loss.

Newborns too are affected, so get them tested

Dr Haitham Morsi

Audio sounds are the building blocks for speech, semantics and emotional development of a child. According to Dr Haitham Morsi, specialist otorhinolaryngology (ENT) at Canadian Specialist Hospital, it is very important for parents to get their newborns screened after a few days of birth without wasting time. It is estimated that three children in 1,000 suffer from hearing disability in the UAE, which could be due to inner-ear infection, some injury or a congenital flaw. “The earlier the hearing loss is detected and action taken, the better it is for the child as his scholastic learning in school, his social communication with friends and family all are impacted,” said Dr Morsi.

Children can suffer from congenital hearing loss due to chromosomal abnormalities, or syndromes. A hearing screening is possible in neonatals as the latest screening methods can measure the extent of loss of hearing in infants. Dr Morsi said that in many children with conductive hearing loss frequent cough, cold and respiratory infections played a major role in impact hearing. “Mild hearing loss is common in children with ear infection, but it usually gets better after the infection clears,” said Dr Morsi. He added that it was important to attend to hearing loss symptoms as it could trigger speech or developmental delays. “This occurs if there is non-resolving effusion behind the ear drum and spread of infection.”

Middle-ear infection or otitis media can be acute or chronic among children. Acute otitis media causes severe pain, aural fullness, fever, headache, unsteadiness and crying. On the other hand, chronic otitis media is accompanied by hearing loss with or without painless ear discharge. It’s diagnosed clinically.

In case of sensory-neural loss of hearing, it is possible to detect as early as a few weeks after the birth of an infant and minimise any developmental deficit in him or her. Parents must get neonatal hearing screening for their newborns. While school-going children can undertake behavioural tests or undergo audiometer testing, in case of infants, sound wave activity is measured with new tests.

Viral, bacterial infections

Dr Morsi said that the most common cause of hearing loss in children could be due bacterial or viral infections, nasal allergy, hypertrophy of adenoids, low immunity and breast-feeding while the infant is lying down. Uncommon causes have been attributed to cholesteatoma (a pearly mass within the middle ear space). The pain starts with activities such as scuba diving or during a take-off or landing while on a plane where an individual experiences pain in the ear due to sudden change in air pressure. This can lead to a sharp pain, blocked ears and in some cases, bleeding in the middle ear.