Hearing loss can affect anyone at any age. It can result from things like heredity, disease, environmental factors, trauma, or simply a consequence of aging.
Hearing loss can also affect both ears or only one, known as unilateral hearing. Some are born unable to hear in one ear, while others develop unilateral hearing in adulthood.
What Is Unilateral Hearing Loss?
According to data produced by the World Health Organization, hearing loss affects roughly five percent of the world’s population.
This makes it one of the leading causes of disability globally — affecting more than 430 million people.
Furthermore, hearing loss has widespread effects on overall health, from cognitive decline to impaired socialization (especially among children).
Hearing loss also casts an economic burden, from health care costs, unemployment rates, and the losses in work productivity.
This only accounts for the hearing loss that is actually diagnosed.
Many people live with undiagnosed hearing loss. One example is unilateral hearing loss, a condition that affects normal hearing.
Unilateral hearing loss (UHL) refers to hearing loss in one ear, as opposed to bilateral hearing loss, which affects both ears.
This condition is also referred to as single-sided hearing loss. Unilateral hearing loss occurs when the hearing in one ear is within normal ranges, and the other has some degree of reduction in normal hearing.
Is Unilateral Hearing Loss a Common Condition?
This condition varies in severity and degree, ranging from mild to profound hearing loss or even deafness. It can affect anyone at any age.
However, many people experience unilateral hearing loss from birth.
Auditory statistics by the American Speech-Language-Hearing Association state that one out of every 1,000 children is born with congenital unilateral hearing loss.
Those with pediatric UHL are at a greater risk for experiencing academic and social-emotional issues and speech-language difficulties.
That is why early diagnosis and intervention are key to creating a good quality of life.
However, UHL is not limited to a condition at birth. It can also occur later in life, either gradually or suddenly.
Single-Sided Deafness (SSD) and UHL
Single-sided deafness, also known as unilateral deafness, is a more severe type of UHL where the hearing loss is so reduced it is considered non-functional (deaf).
In simple terms, someone with single-sided deafness hears very little to no sound in the affected ear. Hearing devices like hearing aids or interventions such as a cochlear implant may or may not be effective.
What Are the Symptoms and Causes of Unilateral Hearing Loss?
One of the most common symptoms among those with unilateral hearing loss is the difficulty or the inability to locate or pinpoint where sounds are coming from, called sound localization or spatial hearing.
Instead, those with UHL often perceive all sounds coming from their good ear when sounds actually originate in the direction of their affected ear.
This condition acts as sort of a blind spot when it comes to locating a sound source.
Also, those with UHL experience limited speech understanding in noisy environments.
Background noises flood the normal hearing ear along with the speech, making concentration and the differentiation of sounds very difficult.
Due to this fact, a reported positive from those with UHL is sometimes better sleep since they experience little to no background noise when sleeping on their better hearing ear.
Some other common signs and symptoms of UHL could include:
- Tinnitus (ringing) in the affected ear.
- Constantly having to ask others to repeat themselves.
- Irritability and fatigue from struggling to listen all day.
- Favoring one ear over the other in conversations.
- Having to increase the volume on televisions, radio, etc.
- Inattentiveness (common among school-age children).
There are many causes of unilateral hearing loss, ranging from congenital hearing loss at birth to even trauma.
Two main types of hearing loss can result in UHL: sensorineural hearing loss and conductive hearing loss.
Unilateral Sensorineural Hearing Loss
Sensorineural hearing loss is the most common type of hearing loss.
This type of hearing loss is a result of normal aging and falls under the category of age-related hearing loss (presbycusis).
Although sudden sensorineural hearing loss can happen, it typically happens gradually over time and affects older adults.
Unilateral sensorineural hearing loss happens when components in the inner ear degenerate due to aging, such as damage to hair cells, cochlea, and auditory nerves.
Some other causes of unilateral sensorineural hearing loss can include medication side effects, Ménière's disease, genetic abnormalities, cochlear otosclerosis, and more.
Unilateral Conductive Hearing Loss
Conductive hearing loss is often the result of trauma or obstruction of the structures or the auditory system that inhabit sounds from passing through the outer and middle ear.
This type of unilateral hearing loss can be temporary or permanent.
Some unilateral conductive hearing loss causes include obstruction from an earwax buildup, trauma to the small bones in the middle ear, chronic ear infections, and more.
Testing and Diagnosis
Binaural hearing (ability to hear in both ears) is usually tested among infants at birth and through annual hearing tests among school-age children.
But these sorts of tests are not always definitive. The only way to get a thorough hearing test is by scheduling an appointment with a hearing care provider.
Hearing care professionals include those who work in audiology and otolaryngology, such as audiologists or ear, nose, and throat (ENT) physicians.
These professionals are trained to test for the prevalence of hearing impairments.
Treatment and Management Options for UHL
Suppose you’ve already been diagnosed with unilateral hearing loss.
In that case, it's best to speak with your audiologist about the different treatment options available, ranging from non-medical management (amplification from hearing aids) to surgical interventions like a hearing implant (cochlear implants).
Other treatment and management options could include:
- Contralateral Routing of Signal (CROS) Devices. A CROS system uses two separate devices. One device is a hearing aid (worn on the better ear). The other drive contains a microphone that picks up the sounds from the poor hearing side, sending it to the hearing aid in your better ear.
- Bone Conduction Hearing System. A bone conduction hearing system (also called a bone-anchored hearing system) uses an external sound processor that attaches to a headband or a surgical implant. This processor picks up sound from the poor hearing ear and sends it to the other side via bone conduction. It improves sound awareness on the affected side.
For school-aged children, management strategies for UHL are often taught by professionals like speech-language pathologists who are trained in specific interventions to help children cope with hearing loss within the classroom setting.
Hearing loss can happen at any stage of life. Unilateral hearing loss is a type of hearing loss that only affects one ear.
This condition can present its own unique set of challenges, such as difficulty locating sounds.
Thankfully, there are effective options out there to help manage this condition.
The best course of action is to consult an audiologist who can provide you with the best treatment options.
For more resources on hearing loss, explore the USA Rx blog here.