Unilateral Hearing Loss (Single-Sided Deafness)

What is unilateral hearing loss?

A unilateral hearing loss occurs when hearing in one ear is within normal limits, while hearing in the other ear has some degree of reduction in hearing. Unilateral hearing loss can range from mild to profound in severity. You can have unilateral hearing loss from birth, or hearing loss can develop later in life, suddenly or gradually.

What is single-sided deafness?

Single-sided deafness (SSD) is a type of unilateral hearing loss where the reduction in hearing is so severe that your ear is considered to be non-functional or deaf. That is, a person has no or limited access to sound in that ear and may or may not benefit from hearing aid on that ear.

How common is unilateral hearing loss?

An estimated 60,000 Americans have unilateral hearing loss. The condition affects all genders and ages.

Approximately 1 child in 1,000 is born with unilateral hearing loss, and approximately 7% of adults in the U.S. have unilateral hearing loss.

Signs and symptoms of single-sided deafness may include:

• Tinnitus (ringing) in only one ear.
• Asking others to repeat themselves.
• Favoring one ear over the other on the phone or in conversations.
• Having trouble localizing sounds.
• Turning the television up louder.
• Noticing it is more difficult to understand conversations, especially in noisy environments.
• Withdrawing from certain social situations.
• Feeling fatigued or irritable at the end of the day from listening.

What should I do if I think I have unilateral hearing loss or single-sided deafness?

If you suspect you have hearing loss, schedule a hearing test with an audiologist. If you suspect you have a sudden hearing loss, schedule an appointment with an ear, nose, and throat (ENT) physician immediately, as this may need to be treated right away for best results.

If you have been diagnosed with unilateral hearing loss, talk to your audiologist about non-medical management options such as amplification and communication strategies and/or an ENT physician to discuss medical or surgical intervention such as implantable devices. Managing the hearing loss earlier rather than later often yields better results, so it's important to seek treatment options as soon as your hearing loss is identified.

Why is it important to manage unilateral hearing loss or single-sided deafness?

It's beneficial to hear with two ears for several reasons. Our brain “hears” best when it receives input from both ears. For example, input from both ears allows our brain to separate speech from background noise to hear better in noisy places, such as restaurants, classrooms and social gatherings.

Sound localization is only possible when there is sound input from both ears. For safety reasons, this is especially important when you need to identify a sound source quickly. In addition, our brain actually amplifies the intensity of the sound when it receives input from both ears so that we can hear softer sounds with two ears compared to only one ear.

How is unilateral hearing loss managed?

Hearing loss treatments often depend on what causes your hearing loss and how severe it is.

Management options for unilateral hearing loss or single-sided deafness include:

• Hearing Aid: A hearing aid is the most common device option for unilateral hearing loss when you have a mild or moderate hearing loss. Your hearing aid is programmed to increase the loudness of the incoming sounds so that they're audible and compensate for the reduction in hearing. A hearing aid may be an option for you if it's able to make speech loud and clear enough to meet your listening needs.
• Contralateral routing of signal (CROS) devices: A CROS system involves two separate devices, both of which look like a hearing aid. One of the devices is indeed a hearing aid — it's worn on the better ear. The other device contains a microphone that picks up the sounds from that side and sends it to the hearing aid on your better ear. CROS hearing systems don't restore hearing in the poorer hearing ear, and they don’t help localize sounds. But they do allow you to pick up sounds from the poorer ear side.
• Cochlear implant: A cochlear implant involves a surgically implanted device as well as an external sound processor. These two parts work together to bypass part of the inner ear that is causing difficulty hearing and directly stimulate the hearing nerve. The goal of the cochlear implant is to provide sound to the ear with hearing loss. A cochlear implant may help with speech understanding, ringing in your ear and sound localization, and is an alternative to hearing aids.
• Bone conduction hearing system: A bone conduction or bone-anchored hearing system includes an external sound processor that attaches to a headband or a surgical implant. The sound processor picks up sound from the poorer-hearing side and sends it to the better hearing ear by bone conduction. The goal of the bone-anchored hearing system for single-sided deafness is to provide sound awareness on the poorer-hearing side. Bone-anchored hearing systems do not restore hearing in the ear with hearing loss. Instead, they allow you to be aware of sounds on the side with the non-functional ear. Bone-anchored hearing systems also do not help with ringing in the ear or sound localization but may be a good option particularly when a cochlear implant is not an option.
• Frequency modulation (FM) systems: FM systems use radio waves to send speech and other signals from a microphone directly to a receiver. The receiver may be a sound field speaker or sent to an ear-level device, such as a hearing aid, cochlear implant, or as a stand-alone piece worn in the better-hearing ear. With an FM system, you’ll hear voices more loudly and clearly when in background noise or in a reverberant listening environment, or if the speaker is a distance from you. FM systems are often used by schoolchildren in the classroom to hear their teachers and peers better, but they can often be purchased separately for individual use outside of the classroom for children and adults.

In addition to devices, communication strategies and environmental modifications can help people with hearing loss communicate more effectively.

How can I prevent unilateral hearing loss or single-sided deafness?

Exposure to loud noises is one of the most preventable causes of hearing loss. To lower your family’s risk of noise-induced hearing loss:

• Turn down the volume (if possible) on electronic devices, earbuds and toys.
• Wear sound-reducing earplugs (inside your ears) or earmuffs (outside your ears) when attending loud events or working with power tools or in noisy environments.

What is the prognosis (outlook) for people who have unilateral hearing loss?

Some people with unilateral hearing loss regain part or all of their hearing with treatment. But for many people, hearing loss is permanent. New hearing-assist devices are helping more people hear better.

When should I call the doctor?

You should call your healthcare provider if you develop hearing loss or experience:

• Balance problems or dizziness.
• Chronic ringing in ears (tinnitus).
• Severe earache.
• Sudden deafness.

What questions should I ask my doctor?

You may want to ask your healthcare provider:

• Why did I lose my hearing?
• What type of hearing loss do I have?
• What is the best treatment for me?
• Should I consider a hearing aid?
• What changes can I make to protect my hearing?
• Should I look out for signs of complications?

A note from Cleveland Clinic

Many people have some degree of hearing loss in one or both ears. Unilateral hearing loss can affect your ability to take part in conversations and activities. Infants born with unilateral hearing loss or single-sided deafness can get help from early speech and language therapies. Hearing specialists can determine the best treatments to help you hear better. Hearing assist devices may help.