Hearing loss is often a natural part of the aging process. Sometimes, we may not even know it’s happening. According to Statistics Canada, many Canadians aged 40 to 79 are unaware they have it. Hearing loss can be subtle at first and turn into more noticeable experiences, like reduced clarity and difficulty hearing certain sounds and pitches. While aging is the most common cause, extreme noise exposure or biological dysfunction can also lead to these conditions. The main types of hearing loss are conductive, sensorineural, and mixed. In this post, we’ll explore the differences, including options for treatment.
Difference Between Conductive and Sensorineural Hearing Loss
The ear is anatomically split into three sections: external, middle, and inner. The external or outer ear consists of the following components:
- Auricle (Pinna): the cartilage and skin
- External auditory canal: the tube connecting the outer to the inner ear
- Eardrum: the membrane that divides the external from the middle ear
The middle ear has the following parts:
- Ossicles: three tiny bones that transmit sound waves to the inner ear
- Eustachian tube: links the middle ear with the back of the nose and helps to equalize pressure in the middle ear to transfer sound waves properly
Finally, the inner ear consists of:
- Cochlea: contains the tiny hairs and nerves for your auditory nervous system
- Vestibule: has receptors for forward, backward, and up and down motion balance
- Semicircular canals: contain hair cell receptors responsible for rotary motion balance
Hearing loss can impact one or more of the three sections and their respective parts. Sensorineural hearing loss impacts the inner ear or auditory nervous system, while conductive hearing loss affects the outer or middle ear.
Sensorineural Hearing Loss
As mentioned above, sensorineural hearing loss consists of damage to the inner ear or nerves responsible for delivering sound to the brain. The cochlea in your inner ear has tiny hair cells that receive sound waves and convert them into electrical impulses for the brain. When these functions are damaged, it impacts our ability to decipher sounds. This is the most common type of hearing loss among older adults but can affect people of all ages.
Causes
Sensorineural hearing loss can be caused by aging or noise-induced hearing loss, which is sudden or prolonged exposure to loud noises. Other causes of this condition can include the following:
- Injuries, specifically to the head
- Genetic predisposition
- Bacterial or viral infections of the inner ear
- Ototoxic medications, like aspirin (in large doses), ibuprofen, naproxen, neomycin, and bleomycin, among others
- Meniere’s disease (a disorder causing periods of ringing in the ears)
Symptoms
People with sensorineural hearing loss may experience a reduced ability to hear sounds with clarity and high frequencies, like high-pitched voices. The following signs may indicate this kind of condition:
- Turning up the volume on televisions or phones
- Misunderstanding conversations
- Constantly asking others to repeat what they said
- Thinking that other people are always mumbling
- Straining to hear others
- Tinnitus (ringing or buzzing) in the ears
Treatment
Treatment for sensorineural hearing loss often involves hearing aids. Because it’s an age-related or noise-induced condition, damage usually cannot be reversed. Hearing aid devices can be an excellent way to improve the reception of sounds around you. Cochlear implants may be an option if these devices can’t recover hearing abilities. In some cases, if an inner ear infection causes this loss, antibiotics can be used for treatment.
If you experience sudden hearing loss over a few hours or days, visit a hearing specialist immediately, as any delay in seeking help can decrease the effectiveness of medicinal treatments.
Conductive Hearing Loss
Conductive hearing loss can be temporary or permanent and impacts the outer and middle ear, stopping sound waves from travelling to the inner part that contains the auditory nerves. This condition can affect anyone but commonly impacts children who insert objects into their ears or experience frequent ear infections.
Causes
The causes of conductive hearing loss can come from physical blockages or dysfunctioning eardrums or bones. Other common causes include the following:
- Excess earwax
- Ruptured eardrum
- Fluid buildup from an outer or middle ear infection
- Abnormal bone growth
- Hearing disorders like atresia (the absence or closure of the ear canal) or stenosis (ear canal narrowing)
- Abnormal growths or tumours
- Eustachian tube dysfunction
Symptoms
Some signs of conductive hearing loss overlap with sensorineural but are largely distinct due to the differences in locations and causes. Here are some of the symptoms to look for:
- Reduced ability to hear sound but not clarity
- A “plugged” ear sensation
- Tinnitus (ringing or buzzing) in the ears
- Pain or fluid buildup due to an ear infection
Treatment
Conductive hearing loss treatment can reverse the impairment in many cases. Depending on the cause of your condition, treatment may consist of the following:
- Removing earwax
- Removing any foreign objects from the ear canal
- Prescription antibiotics if its an ear infection
- Surgery
- Hearing aids, if the hearing loss is irreversible
Mixed Hearing Loss
This condition combines sensorineural and conductive hearing loss, occurring in the inner, middle, and outer ear. People with mixed hearing loss have different experiences from those suffering from one type or the other because both sets of symptoms are usually present. For example, a person with aging-related sensorineural hearing loss and conductive hearing loss due to a physical blockage of earwax may experience the following symptoms:
- Difficulty deciphering sounds in noisy environments
- Reduced hearing clarity that makes it hard to make out consonants
- Difficulty hearing high-pitched sounds
- Tinnitus, or ringing in the ears
- Pressure, pain or a “plugged” sensation in the ears
- Abnormal odours coming from the ear canal
- Fluid discharge
Treatment for mixed hearing loss is often a multi-step process that involves taking care of the conductive and sensorineural aspects separately. Typically, conductive hearing loss is treated first by removing blockages or prescribing antibiotics for ear infections. Once this occurs, there should be a noticeable difference in your hearing abilities.
Sensorineural hearing loss can be more challenging to treat because it’s often permanent, as outlined above. Hearing aids are typically the best option to enhance your ability to receive and interpret sounds.
Hearing Loss Prevention
Sensorineural and conductive hearing losses have varying causes and can lead to unavoidable permanent damage, like in the case of aging. Despite this, there are essential steps you can take to protect your ears. For example, you can:
- Wear earplugs or earmuffs in noisy environments or when operating loud machinery
- Get a hearing test every three to five years
- See a doctor or specialist immediately if you notice anything unusual, like blockages or a suddenly reduced ability to hear
Getting the Hearing Help You Need
If you are concerned about your hearing, an online test can help determine if you need to see an audiologist. From there, these hearing health professionals can diagnose the type of hearing loss you have. Whether you experience the symptoms outlined above, have a family history of hearing loss, or need peace of mind, consider booking an in-person appointment at Robillard Hearing Centres.
We understand that a hearing loss diagnosis can feel overwhelming. That’s why we’re here. Our audiologists can help highlight details about your condition and facilitate empathetic discussions about what this means for your health. Based on your diagnosis, our team can recommend the types of hearing aids suitable for you. If you have questions about your hearing health, reach out to us today.