Nerve deafness; Hearing loss - sensorineural; Acquired hearing loss; SNHL; Noise-induced hearing loss; NIHL; Presbycusis Sensorineural deafness is a type of hearing loss. It occurs from damage to the inner ear, the nerve that runs from the ear to the brain (auditory nerve), or the brain. The ear consists of external, middle, and inner structures. The eardrum and the 3 tiny bones conduct sound from the eardrum to the cochlea.
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. Symptoms may include:
Other symptoms include:
CausesThe inner part of the ear contains tiny hair cells (nerve endings), that change sounds into electric signals. The nerves then carry these signals to the brain. Sensorineural hearing loss (SNHL) is caused by damage to these special cells, or to the nerve fibers in the inner ear. Sometimes, the hearing loss is caused by damage to the nerve that carries the signals to the brain. Sensorineural deafness that is present at birth (congenital) is most often due to:
SNHL may develop in children or adults later in life (acquired) as a result of:
In some cases, the cause is unknown. What to Expect at Your Office VisitThe goal of treatment is to improve your hearing. The following may be helpful:
A cochlear implant may be recommended for certain people with severe hearing loss. Surgery is done to place the implant. The implant makes sounds seem louder, but does not restore normal hearing. You will also learn strategies for living with hearing loss and advice to share with those around you for talking to someone with hearing loss. ReferencesArts 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. 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. National Institute on Deafness and Other Communication Disorders website. Noise-induced hearing loss. NIH Pub. No. 14-4233. www.nidcd.nih.gov/health/noise-induced-hearing-loss. Updated May 31, 2019. Accessed June 23, 2020. 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. Version InfoLast reviewed on: 4/13/2020 Reviewed by: Josef Shargorodsky, MD, MPH, Johns Hopkins University School of Medicine, Baltimore, MD. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.  How do you rule out sensorineural hearing loss?Doctors use several types of tests to properly diagnose sensorineural hearing loss.. Physical exam. A physical exam can help differentiate SNHL from conductive hearing loss. ... . Tuning forks. A doctor may use a tuning fork test as an initial screening. ... . Audiogram.. How do you differentiate and diagnose a patient either having conductive or sensorineural deafness?Tuning fork tests like the Weber or Rinne test can help find the location of the hearing loss and determine if it is conductive or sensorineural, reports University of Iowa Health Care. Doctors can get additional information about your hearing loss from tympanometry and auditory brainstem response testing.
What test can help you detect sensorineural hearing loss?Audiometry tests can detect whether you have sensorineural hearing loss (damage to the nerve or cochlea) or conductive hearing loss (damage to the eardrum or the tiny ossicle bones).
How do you classify types of hearing loss?The term dB HL describes your hearing loss in decibels. The table below shows a common way to classify hearing loss.
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Degree of Hearing Loss.. |
