Hearing loss
Decreased hearing; Deafness; Loss of hearing; Conductive hearing loss; Sensorineural hearing loss; Presbycusis
Hearing loss is being partly or totally unable to hear sound in one or both ears.
The ear consists of external, middle, and inner structures. The eardrum and the three tiny bones conduct sound from the eardrum to the cochlea.
Considerations
Symptoms of hearing loss may include:
- Certain sounds seem overly loud in one ear
- Difficulty following conversations when two or more people are talking
- Difficulty hearing in noisy areas
- Trouble telling high-pitched sounds (such as "s" or "th") from one another
- Less trouble hearing men's voices than women's voices
- Hearing voices as mumbled or slurred
Associated symptoms may include:
- Feeling of being off-balance or dizzy (more common with Ménière disease and acoustic neuroma)
- Feeling of pressure in the ear (in the fluid behind the eardrum)
- Ringing or buzzing sound in the ears (tinnitus)
We often take for granted all of the sounds around us, the bark of a dog, the buzz of a bee, or the melody of our favorite symphony. Yet for many people, the world is a very quiet place. They've lost the ability to hear sounds in one or both ears. Let's talk about hearing loss. To understand how you lose hearing, you first need to know what normally happens inside your ear when you hear. Say that a fire engine roars past. First, the sound of the siren reaches your eardrum in your outer ear. Your eardrum vibrates, which moves three tiny bones in your middle ear. These bones push the sound along to the cochlea, a fluid-filled chamber in your inner ear. The cochlea is lined with tiny hairs that vibrate when the sound waves hit them. These hairs convert the sound waves into an electrical signal. That's when your brain realizes that a fire engine is headed toward you. Hearing loss can have many different causes. Loud noises, pressure changes while you're scuba diving, or a head injury can all damage the delicate structures in your ear that allow you to hear. Infections like measles, mumps, and meningitis can also damage the ear. Sometimes earwax can build up in your ear and block your hearing like a plug. As you get older, you may gradually lose your hearing, even if you don't have an illness or injury. When the damage or other problem is to your outer or middle ear, it's called conductive hearing loss. For example, your eardrum may not vibrate when you hear sound. Or, the tiny bones in your middle ear may not move sound to the inner ear. Sensorineural hearing loss is caused by a problem in the inner ear. Often it's because the tiny hair cells that move sound through the ear don't work right because of damage or disease, and stem cells in the ear can't keep up with the repair. If you have problems with both your inner and outer ear, then you have mixed hearing loss. So, how do you treat hearing loss? If you're noticing that voices sound fuzzy and you can't make out what people are saying, see your doctor for a hearing test. The doctor will examine your ears, and give you a test called audiometry to check the type and amount of hearing you've lost. You may also have imaging tests such as a CT or MRI scan if you've had a head injury. A hearing aid can amplify sounds to help you hear more clearly. Today's hearing aids are so small they're barely noticeable. If you have a buildup of earwax in your ear, an ear syringe filled with warm water can help flush it out. Sometimes surgery can be done to fix damage in your ear and improve your hearing. Don't accept hearing loss as an inevitable part of growing older. See your doctor for a hearing evaluation. Often, hearing loss that's due to a problem in your outer or middle ear can be reversed. Protect the hearing that you do have by avoiding loud noises, and wearing earplugs when you have to be exposed to loud sounds.
Causes
Conductive hearing loss (CHL) occurs because of a mechanical problem in the outer or middle ear. This may be because:
- Sound is not reaching the eardrum.
- The eardrum is not vibrating in response to sound.
- The 3 tiny bones of the ear (ossicles) are not conducting sound properly.
Causes of conductive hearing loss can often be treated. They include:
- Buildup of wax in the ear canal
- Damage to the very small bones (ossicles) that are right behind the eardrum
- Fluid remaining in the ear after an ear infection
- Foreign object that is stuck in the ear canal
- Hole in the eardrum
- Scar on the eardrum from repeated infections
Sensorineural hearing loss (SNHL) occurs when the tiny hair cells (nerve endings) that detect sound in the inner ear are injured, diseased, do not work correctly, or have died. This type of hearing loss often cannot be reversed.
Sensorineural hearing loss is commonly caused by:
- Acoustic neuroma
- Age-related hearing loss
- Childhood infections, such as meningitis, mumps, scarlet fever, and measles
- Ménière disease
- Regular exposure to loud noises (such as from work or recreation)
- Use of certain medicines
Hearing loss may be present at birth (congenital) and can be due to:
- Birth defects that cause changes in the ear structures
- Genetic conditions (more than 400 are known)
- Infections the mother passes to her baby in the womb, such as toxoplasmosis, rubella, or herpes
The ear can also be injured by:
- Pressure differences between the inside and outside of the eardrum, often from scuba diving
- Skull fractures (can damage the structures or nerves of the ear)
- Trauma from explosions, fireworks, gunfire, rock concerts, and earphones
Home Care
You can often flush wax buildup out of the ear (gently) with ear syringes (available in drug stores) and warm water. Wax softeners (like Cerumenex) may be needed if the wax is hard and stuck in the ear.
Take care when removing foreign objects from the ear. Unless it is easy to get to, have your health care provider remove the object. Don't use sharp instruments to remove foreign objects.
See your provider for any other hearing loss.
When to Contact a Medical Professional
Contact your provider if:
- Hearing problems interfere with your lifestyle.
- Hearing problems do not go away or become worse.
- The hearing is worse in one ear than the other.
- You have sudden, severe hearing loss or ringing in the ears (tinnitus).
- You have other symptoms, such as ear pain, along with hearing problems.
- You have new headaches, weakness, or numbness anywhere on your body.
What to Expect at Your Office Visit
The provider will take your medical history and do a physical exam.
Tests that may be done include:
- Audiometric testing (hearing tests used to check the type and amount of hearing loss)
- CT or MRI scan of the head (if a tumor or fracture is suspected)
- Tympanometry
The following surgeries may help some types of hearing loss:
- Eardrum repair
- Placing tubes in the eardrums to remove fluid
- Repair of the small bones in the middle ear (ossiculoplasty)
The following may help with long-term hearing loss:
- Assistive listening devices
- Safety and alert systems for your home
- Hearing aids
- Cochlear implant
- Learning techniques to help you communicate
- Sign language (for those with severe hearing loss)
Cochlear implants are only used in people who have lost too much hearing to benefit from a hearing aid.
References
Arts HA, Adams ME. Sensorineural hearing loss in adults. In: Flint PW, Francis HW, Haughey BH, et al, eds. Cummings Otolaryngology: Head and Neck Surgery. 7th ed. Philadelphia, PA: Elsevier; 2021:chap 152.
Eggermont JJ. Types of hearing loss. In: Eggermont JJ, ed. Hearing Loss. Cambridge, MA: Elsevier Academic Press; 2017:chap 5.
Kerber KA, Baloh RW. Neuro-otology: diagnosis and management of neuro-otological disorders. In: Jankovic J, Mazziotta JC, Pomeroy SL, Newman NJ, eds. Bradley and Daroff's Neurology in Clinical Practice. 8th ed. Philadelphia, PA: Elsevier; 2022:chap 22.
Le Prell CG. Noise-induced hearing loss. In: Flint PW, Francis HW, Haughey BH, et al, eds. Cummings Otolaryngology: Head and Neck Surgery. 7th ed. Philadelphia, PA: Elsevier; 2021:chap 154.
Shearer AE, Shibata SB, Smith RJH. Genetic sensorineural hearing loss. In: Flint PW, Francis HW, Haughey BH, et al, eds. Cummings Otolaryngology: Head and Neck Surgery. 7th ed. Philadelphia, PA: Elsevier; 2021:chap 150.
Weinstein B. Disorders of hearing. In: Fillit HM, Rockwood K, Young J, eds. Brocklehurst's Textbook of Geriatric Medicine and Gerontology. 8th ed. Philadelphia, PA: Elsevier, 2017:chap 96.
Version Info
Last reviewed on: 5/30/2022
Reviewed by: Josef Shargorodsky, MD, MPH, Johns Hopkins University School of Medicine, Baltimore, MD. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
