This topic provides information about sensorineural hearing loss (SNHL). Be sure to check our general page on all types of hearing loss if you are looking for more information.
What is Sensorinueral Hearing Loss?
Sensorineural hearing loss is a type of hearing loss that involves damage to the inner ear (cochlea) or to the nerve pathways that run from the inner ear to the brain (vestibulocochlear nerve, cranial nerve VIII).
Sensorineural hearing loss can be broken down into two different subsections:
- sensory hearing loss
- neural hearing loss
Sensory Hearing Loss
The sensory portion of sensorineural hearing loss is a result of dysfunction of the organ of hearing, called the cochlea. Most sensory hearing loss is the result of abnormalities of the tiny hair cells in the cochlea.
Neural Hearing Loss
The neural component of sensorineural hearing loss involves dysfunction of the cranial nerve which connects the cochlea to the auditory centers of the brain, called the vestibulocochlear nerve, or cranial nerve VIII.
What Causes Sensorineural Hearing Loss?
Sensorineural hearing loss may be present at birth. This is called a congenital sensorineural hearing loss and may be the result of an underdeveloped cochlea or vestibulocochlear nerve, exposure to a virus such as Rubella in the womb, or a rare chromosomal syndrome.
An acquired sensorineural hearing loss may also develop over an individual’s lifetime. An acquired sensorineural hearing loss has several possible causes, including:
- Hereditary or genetic progressive hearing loss
- Extended exposure to loud noises
- Ototoxic medications (drugs that are toxic to the ears)
- Disease or illness
- Aging, also termed presbycusis
- Physical trauma
What are the Symptoms of Sensorineural Hearing Loss?
Symptoms of a sensorineural hearing loss can include:
- Difficulty hearing or understanding conversation, especially in noisy environments
- Difficulty understanding television
How is it Diagnosed?
A sensorineural hearing loss is diagnosed by an Audiologist after completing a comprehensive hearing evaluation. Testing for a sensorineural hearing loss will typically include the following:
- Acoustic Reflexes
- Air conduction pure-tone thresholds
- Bone conduction pure-tone thresholds
- Speech discrimination test
The use of these tests will determine whether the hearing loss is sensorineural, or whether it is a different type of hearing loss. To distinguish whether the hearing loss is sensory versus neural, Otoacoustic Emission (OAE) and Auditroy Brainstem Response (ABR) testing may also be included.
How is it Treated?
SNHL is the most common type of permanent hearing loss. In most cases it cannot be medically or surgically corrected. Sensorineural hearing loss is classified in different degrees including, mild, moderate, severe and profound.
Sensorineural hearing loss results in difficulty hearing soft sounds and can lead to impaired communication. Sensorineural hearing loss can be effectively managed with hearing aids or other hearing technology.