Health Watch (Sensorineural Hearing Loss)

Bad H(ear) Day! 

The human ear is a vital sense organ in the body. Any minor injury or infection inflicted on its delicate parts can induce irreversible damage to the aural organ in want of timely care and cure. The latest condition plaguing the pair of ears is sensorineural hearing loss. ENT specialists weigh in.

Pic Courtesy: Wikimedia Commons 

By PRAMITA BOSE

Do you sleep with your earbuds on, listening to your favourite playlist? Or do you keep your mobile phone in bed beside your head and ears, frequently checking time and receiving emergency calls in the dead of the night, if any? Or are you constantly exposing your ears to loud, ear-splitting music on your iPod or boom box? Beware of such habits. These could result in partial or permanent hearing impairment.

Either the sensitive hair cells of the inner ear or the brain’s central processing nerve centres could be affected due to the harmful effects of jarring sounds and noises or on health grounds. Recently, renowned Bollywood playback artiste Alka Yagnik was in news for being afflicted with the disease of sensorineural hearing loss. Audiologists alert that lifestyle caution is paramount to ward off such cases.

Decoding SNHL

The sensorineural hearing loss (SNHL) disorder is caused by a weakness in the nerve of hearing. It results from damage of hair cell receptors in the cochlea (the spiral cavity of the inner ear producing nerve impulses in response to sound vibrations) or due to a tumour disturbing the hearing nerve.

“Reasons may vary from old age (affects both ears and progresses over time), excessive noise exposure, chronic ear diseases, abnormal tissue growths, ototoxic drugs (resulting in hearing loss, ringing sensation in the ear or balance disorders), etc. SNHL could also happen suddenly due to a viral illness. Babies too can be detected with deafness at birth due to SNHL,” informs reputed consultant ENT surgeon Dr. Manusrut from Yashoda Hospitals in Hyderabad.

Studying the symptoms and treating the diseases related to ear, nose and throat, otorhinolaryngologists claim that apart from the inner ear (cochlea), the neuronal pathways connecting the inner ear to the brain can cause SNHL. Infection, head injury and of course, heavy medication with side effects are some of the other reasons that might escalate the problem with a rapid loss of hearing in just a few days.

Ace ENT doctor Dr. Rohit Saxena adds several viruses like “HIV, mumps, influenza, measles” to the list that are known to cause SNHL.

“In this case, sounds may be unclear or muffled. Particularly, high-pitched sounds may not be audible at all to the patient like the voices of women, doorbells, alarms, et al. Plus, there could be difficulty in understanding speech because of a noisy ambience. A continuous hissing sensation could be felt in the ears,” inputs Dr. Saxena, who also heads the ENT department at Sharda Hospital in Greater Noida.

“Sad but true, the syndrome is generally permanent and impacts the clarity and loudness of sounds. The common signs of SNHL include a buzzing and ringing feeling in the ears. Prolonged hours of contact with the industrial environments, machines or construction activity in case of civil engineers, technical personnel and masons may lead to the destruction of actual hair cells of the cochlea,” reports eminent ENT expert Dr. P Harihara Murthy of Apollo Spectra Hospital, Bangalore.

Moreover, genetic mutation could be a cause for congenital hearing loss (early-onset SNHL) or a key factor in its later development in life, he adds ahead. 

It’s No Music to the Ears!

From musicians, rockstars, singers to today’s generation of music junkies — all are exposed to loud music, blaring beats, electronic sounds, noisy beeps, earphones and excessive mobile usage.

Can these be responsible for sensorineural hearing loss?

“Incessant exposure to loud noises can potentially cause SNHL. There has to be a restriction of daily consumption of loud noise and the decibel levels. This gamut encapsulates both professional and recreational exposure,” observes Dr. Manusrut.

Ear-drum beating music can harm the cochlea's fragile hair cells, especially when its intensity reaches a crescendo for an overstretched period of time. “Permanent hearing loss stems from the non-restoration of hair cells once being destroyed due to repeated onslaughts of loud music, whether it be from personal audio devices or in clubs or at concerts,” notes Dr. Saxena.

Road to Recovery

The common query is whether the auditory senses of a human ear can attain normalcy after the problem subsides. Or should the patient be always mindful of listening to sounds with only lower decibels?

After suffering from sensorineural hearing loss (SNHL), the degree and origin of the damage will determine how well the auditory senses can function again.

“In certain situations, such as transient hearing loss brought on by a sudden exposure to loud noises, the ability to hear may fully or partially be regained. Patients are advised to watch out for further damages and protect their ears by listening to sounds at minimal decibel levels to prevent additional stress and injury. Turning down the audio volume is one of the safest listening techniques in the recuperating stage,” prescribes Dr. Saxena.

Unhealthy Habits to Unfollow

Many people have a habit of sleeping with mobile phones on and keeping the device besides their head and ears. Also, many fall asleep with the earbuds on. Can these affect the brain cells, sensitive nerves and the ear, resulting in hearing loss?

“We are already seeing such cases in our daily routine. Teens with such behaviour are increasingly complaining of SNHL and a ringing sensation in the ear called Tinnitus, which is also irreversible. Professionals exposed to consecutive meetings with unceasing usage of headphones are also suffering from hearing issues,” rues Dr. Manusrut.

Echoing similar views, Dr. Saxena states that “such bad habits could bear severe consequences as far as general health is concerned besides triggering hard of hearing.”

Endlessly taxing the auditory system and delicate ear nerves might emanate aggravated noise-induced hearing loss over time. Additionally, the proximity of mobile phones to the body and direct contact with the ears and the head may induce discomfort and deprive adequate hours of sound sleep.

“However, there is no concrete proof from researches that these gadgets directly damage brain cells or cause hearing loss,” reminds Dr. Saxena. “Sleep disturbances and prolonged noise exposure might have an indirect impact on our well-being. Therefore, it is medically instructed to restrict the timespan and the volume of sound exposure within permissible limits,” he shares.

With the ongoing studies exploring the long-term effects of low-level radiation, Dr. Murthy says that “electromagnetic radiation from mobile phones is sometimes argued to negatively impact the brain cells and the nerves.”

Assisted Hearing

External auditory devices like hearing aids, FM (frequency modulated) system and cochlear implants are said to provide significant assistance to patients with sensory hearing loss. One wonders if these technical advancements help lessen the intensity of hard of hearing to a great degree.

“Patients with moderate-to-severe SNHL can use hearing aids, whereas in severe-to-profound cases, cochlear implants come in handy. Kids born with hearing defects also need implants and a prolonged speech therapy to acquire the sense of speaking or talking,” summarises Dr. Manusrut.

Hearing aids work just as amplification devices function with signal processing. The machine amplifies the sound, making it easier for the damaged hair cells in the cochlea to detect and transmit sound signals to the brain.

Modern digital hearing aids are equipped with advanced technology that adjusts the amplifier based on the environment, cutting the background noise and enhancing speech clarity. They analyse the incoming sounds and change the amplification automatically in response to the received sound as well as block the annoying whistling sounds that can arise with the use of the hearing aid.

“FM systems, often used in conjunction with hearing aids, work by transmitting the sound directly from a microphone worn by a speaker or a source to the listener's or the receiver’s device, thus slashing the impact of distance and background noise or an echo. This technology is specifically beneficial in educational settings, where it helps students with hearing loss catch their teachers’ lectures more clearly,” Dr. Saxena explains the technical process.

Cochlear implants electrically stimulate the auditory nerve. They are more advanced devices designed for individuals with severe-to-profound SNHL who do not benefit from hearing aids. The implant is a tiny, sophisticated electronic device that can generate sounds to a person with deep auditory deficiency. It consists of an external component or a processor that sits behind the ear, capturing and processing sounds, and an internal counterpart placed under the skin by a surgical procedure, which converts these sounds into electrical impulses. The patient gets adjusted to the new sound within weeks.

“The impulses are sent to electrodes in the cochlea to stimulate the auditory nerve, thus allowing the brain to perceive sound. This technology can provide a sense of hearing to those who are completely hard of hearing. With this hassle-free equipment, patients can upgrade their ability to seamlessly communicate and interact with their surrounding environment,” details the doctor.

Nocturnal protocols:

 To reduce sound exposure, it's highly recommended to keep phones away from beds at night or turn on the airplane mode. Mobile phones can also disrupt sleep through notifications, vibrations and screen light, indirectly affecting auditory health and the overall well-being due to poor sleep quality.

 Using earplugs or headphones while sleeping is a strict no-no as this can cause uneasiness, irritation or infections from pressure and moisture buildup, thereby raising the risk of hearing problems like tinnitus or ear contagions over time.

Precautionary measures:

 Reducing the volume and averting perpetual exposure to deafening sounds is the key to prevent SNHL.

 Wear earplugs or noise-canceling headphones in loud environments to protect the ears.

 Prevent ear infections by practising good ear hygiene and avoid putting objects into the ears.

 Post extended periods of loud exposure, give your ears some downtime.

Heightened risks of SNHL:

● Consistent exposure to loud music above 85 decibels compromises on the normal capacity of hearing. The volume can be further cranked up in live concerts, big gigs and at noisy extravaganzas, such as nightclubs or even one’s personal music gadgets can be set with extremely high-frequency sounds.

● Acoustic trauma can be caused by sudden overwhelming noises like electronic honks, alarms and any other sharp screechy sounds unpleasant to the ear.

● Loud music from earphones delivers sound energy directly into the ear canal causing possible damage. The truth is that earbuds can be more injurious than over-the-ear headphones since they rest much closer to the eardrum.

● Maximum risks come from long phone calls with the device being pressed to the ear at length, listening to music even on the go or tuning in to viral videos set to high volume and an indefinite usage of headphones.

FACTOID:

 To enhance hearing and verbal comprehension, turn up the

volume of noises.

 In cases of unexpected SNHL, steroids may be given to improve hearing and reduce inflammation.

 One should never use headphone on high volume or avoid long-term usage of headphone.

 Clear your ears on a regular basis. If there is a family history, be very careful from the word go.

 Try to manage chronic conditions like diabetes and blood pressure, which might affect the hearing ability.

 For optimal results and to preserve the hearing function with stability, early diagnosis and treatments are essential.

 Viral infections like meningitis and meniere’s disease — a disorder of the inner ear causing hearing loss, ringing or buzzing in the ears and vertigo or dizzy spells — can lead to SNHL.

 A majority of congenital SNHL cases result from hereditary defects in the patient's genetic makeup.

 SNHL is more likely to occur in premature newborns with very low birth weight or those required to be urgently put on a ventilator for a long period. Also, birth trauma complications precipitating hypoxia (low levels of oxygen in body tissues inducing breathlessness) during delivery may lead to a baby’s hearing loss. Further, extreme jaundice (hyperbilirubinemia) at birth may cause damage to the auditory nerve.

 SNHL is often genetically acquired at the time of birth or after an infant or a child is born due to pregnancy and childbirth complications or infection, such as cytomegalovirus or rubella. Unique problems are found in young children with congenital or early-onset SNHL.

 Sensorineural hearing loss (SNHL) affects both adults and minors. Usually affecting both ears equally, it gets worse over time. Albeit the causes and prevalence of SNHL may vary between the young and the old, both age groups are susceptible to it.

 It is prevalent in elderly people because they are older and have been exposed to more noise over time. The cumulative effects of their aging process upon the inner ear structures and nerve pathways make their age bracket very vulnerable to SNHL.

 Individuals with exposure to loud noise over a long duration, such as those engaged in professions like civil engineering and music industry as well as persons who use headphones set to high volumes are prone to sensory hearing loss.

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