Hearing is the ability to perceive sound by the human ear. The ear is divided into three compartments, i.e outer, middle and inner ear respectively. Sound waves are picked up by the outer ear (pinna), channelled through the auditory canal causing vibrations on the ear drum. These vibrations then vibrate through the ossicles in the middle ear. This stimulates the sensory hair cells in the inner ear namely the cochlear to produce nerve impulses that are transmitted to the brain to be interpreted as sound. Hence, any disruption in this conduction of sound can lead to hearing loss.

Q: How do I know if I am suffering from hearing loss? What are the possible symptoms I may face?

A: If you answer yes to the following symptoms for yourself or someone you know, you would probably be suffering from hearing loss.

• Frequently asking someone to repeat their questions?
• Having trouble hearing and understanding conversations especially in noisy background?
• Frequently turning up the volume on the TV and radio?
• Having difficulty hearing over the phone?
• Feeling depressed, avoiding conversations and social interactions?
• Feels that someone is mumbling all the time?

There are many among us who stay in denial about our hearing problems. The complaints usually come from the spouse or the family members who noticed those symptoms. Imagine the agony having to scream at you all the time just to get the message through to you and ultimately getting frustrated talking to you. Maybe it is about time to consider consulting an otolaryngologist (ENT) consultant or healthcare professional for help.

Q: What are the types of hearing loss?

A: There are three types of hearing loss i.e conductive, sensorineural and mixed hearing loss. Any problem in the outer or middle ear that prevents sound from being conducted properly is known as a conductive hearing loss. Conductive hearing loss is usually mild or moderate in degree, ranging from 25 to 65 decibels. Sensorineural hearing loss on the other hand is also known as “nerve deafness”. Sensorineural hearing loss results from missing or damaged sensory hair cells of the cochlea. This type of hearing loss can be classified as mild, moderate, severe or profound. Mixed hearing loss is a combination of the two.

Q: What are the other symptoms associated with hearing loss?

A: The other symptoms such as ringing in the ear or tinnitus, ear discharge, dizziness, facial weakness and headaches are to be rectified to rule out other possible causes during the consultation with the clinician.

Q: What are the common causes of conductive hearing loss?

A: Conductive hearing losses are usually temporary. The common causes I encounter are:

• Clogged ear wax. Believe it or not, ear wax is actually a good thing. Its job is to trap dust and other small particles before they reach the eardrum. Ear wax falls out of your ear canal naturally. In the case of excessive ear wax that becomes impacted, it’s best to let a professional remove it as injuring the ear drum can be avoided.
• Ear infection. It is always advisable to seek professional help if you experience any ear ache or discharge from your blocked ear. In severe and recurrent cases, this may even lead to permanent hearing damage or ascending infection affecting the brain that can be detrimental. This can also lead to perforation of the ear drum which may prolong the duration of hearing loss. I would usually advise proper ear hygiene and care before any surgical intervention is recommended to restore the integrity of the ear drum.
• Swimmer’s ear. If you have recently been swimming and are experiencing itching, pain or a feeling of fullness in your ear, you may be suffering from a condition called swimmer’s ear. This infection in your outer ear canal usually occurs when water remains in your ear after you’ve been swimming. It can also be caused by scratches or abrasions in your ear canal caused by using cotton swabs, hairpins or your finger to clean your ear canal. When this condition is properly treated by a medical professional, your hearing typically returns to normal.
• Fluid in the middle ear or glue ear. This occurs especially if you have the habit of forceful blowing of your nose when you are having constant flu due to allergies. The middle ear is connected to the back of the nose via the eustachian tube. The function of this tube is to maintain the ventilation and drainage of the middle ear space. Treating the nasal allergies and draining the middle ear will restore the hearing.

Q: What are the causes of sensorineural hearing loss?

A: Sensorineural hearing loss is usually permanent. It is often related to age which we termed as presbyacusis. The common age where the deterioration of hearing occur is around and after the 5th decade. However, those with strong familial history of hearing loss can encounter it even earlier.

Constant exposure to loud noisy environment in occupations like aviation, mining, factory, plumbing and music industries causes early hearing loss as well. This is termed as Noice-induced hearing loss (NIHL). For example, the noise produced by an aircraft can go as high as 130 dB. Hence, the usage of proper protective hearing gears cannot be stressed upon further. Trauma to the head causing disruption of the sensory nerves and damage to the cochlear invariably lead to permanent hearing damage. In these conditions, I would recommend hearing aids.

Certain antibiotics, chemotherapy and antimalarial drugs have known complications affecting the sensory nerves as well. These drugs may cause temporary or permanent damage depending on the dosage and the duration of treatment. Cessation of the medications sometimes can revert the person to normal hearing threshold. Infectious diseases like mumps, measles and meningitis often affect the hearing equally.

Q: Can one be born with hearing loss?

A: Yes. 1 in 1000 newborns can be born with congenital hearing loss. More than half of all cases of prelingual (before the child can speak) deafness are genetic. The remaining 40-50% of all cases of congenital hearing loss are due to nongenetic effects, such as prematurity, postnatal infections, ototoxic drugs, or maternal infection (with cytomegalovirus [CMV] or rubella). Most cases of genetic hearing loss are autosomal recessive and nonsyndromic.

Q: How do I know if my child has hearing loss?

A: In Malaysia, introduction of Newborn Hearing Screening Programme nationwide where all newborns are screened at birth before being discharged from the hospital has come to full force in recent years. The newborns are tested with a simple device – Otoacoustic Emission (OAE), best done while the baby is asleep in a quiet environment. Those who pass the test are cleared with normal hearing at birth. However, progressive hearing loss during the childhood period cannot be ruled out.

The ones who does not pass the test – REFER are kept for follow up with the otolaryngologist for further evaluation. Failing the first OAE test does not dictate the newborn as the one with hearing loss. Sometimes, the debris and hair in the ear canal can produce similar results. Usually, the newborn will be subjected to a repeat OAE before determining the status of hearing. Subsequent follow up with otolaryngologist, audiology and speech team will aim towards restoring hearing via hearing aids or cochlear implant respectively. The objective of this nationwide programme aims towards restoration of hearing with normal speech, identifying them as early as possible in order for the child to attend normal school.

Q: What will the otolaryngologist do to determine the status of hearing in children and adults?

A: A child learning to speak requires normal hearing threshold. Children with delayed speech are commonly brought to a healthcare professional for possibility of hearing impairment. Both adult and child will be examined for other possible causes of hearing loss by the otolaryngologist before handing them over to the audiologist for further evaluation. A child at preschool age will be subjected to auditory brainstem response (ABR) testing and elder ones with play audiogram. In adults, a pure tone audiometry test is commonly done to determine the level of hearing. Hearing aids are only prescribed depending on the severity of hearing loss.

Q: How does hearing aid work? What are the issues I may face when I wear them?

A: Hearing aids carry sounds from the environment into your ear and make them louder. Most hearing aids nowadays are digital and mostly battery powered. Small microphones within the hearing aid collect sounds from the environment. A computer chip with an amplifier converts the incoming sound into digital code. It then analyses the sound based on your hearing loss, listening needs and the level of the sounds around you. The amplified signals are then converted back into sound waves and delivered to your ears through speakers.

Sadly, up to 40% of the populations who are prescribed hearing aids end up not using them. Common excuses are they are uncomfortable, causing ear ache, too loud and has whistling sounds. These are due to improper fitting of the device. Hence, proper fitting and regular follow ups with the audiology team are important for compliance. Social taboo among our society is another problem. I would always advice them to wear the hearing aids like aided spectacles as spectacles are worn to aid vision, similarly the hearing aids are worn to aid hearing.

Q: I am shy. Can I wear a less noticeable hearing aid?

A: There are various features and styles of hearing aid in the market nowadays. However, the power required varies depending on the severity of hearing loss. The smaller aids may not have the power to give you the improved hearing you may expect.

Completely in the canal (CIC) or mini CIC is molded with silicone material to fit inside your ear canal. It improves mild to moderate hearing loss in adults. Although this is the smallest and least visible aid, it lacks certain features like volume control with short battery span.

In the canal (ITC) hearing aid is molded to fit partially in the ear canal. This style is also suitable for adult with mild to moderate hearing loss. The downside is similar to the CIC style.

In the ear (ITE) hearing aid is custom made as the name mentioned to fit in the ear. This is helpful for people with mild to severe hearing loss. This is easier to handle with longer battery lifespan and better power. However, the ability to pick up background noise is also unavoidable and can be quite annoying.

Behind the ear (BTE) hearing aid hooks over your ear and rests behind the ear. A tube connects the hearing aid to a custom earpiece called an earmold that fits in your ear canal. This type is appropriate for people of all ages with almost any type of hearing loss. This is the traditional type if hearing aid.