The vestibulocochlear nerve, also known as auditory vestibular nerve, is the eighth cranial nerve and is responsible for maintaining balance and hearing in a patient. This special sensory nerve has two nerve branches, the vestibular branch and the cochlear branch. The vestibular branch helps with the balance control of a person, helps a person maintain an upright posture and ascertain their spatial positioning. The function of the cochlear branch is to help the brain to detect sound which is transmitted through vibrations in hair cells. Damage to vestibulocochlear nerve impairs the person’s ability to maintain equilibrium and to hear. There are various factors which damage the vestibulocochlear nerve.
What are the Causes of Nerve Damage in the Ear?
Some of the common causes of nerve damage in the ear are:
The sensory nerve endings (hair cells) of the vestibulocochlear cochlear nerve can get damaged by ear infections. The most common type of ear infection is otitis media, which is the middle ear infection. Another infection is vestibular neuronitis where there is inflammation of the vestibular part of the vestibulocochlear nerve causing balance disorders in the patient. Infections in children, such as measles, mumps and chickenpox, can also cause nerve damage in the ear.
Trauma or injury to the head which causes skull fracture can cause damage to the vestibulocochlear nerve. The vestibulocochlear nerve exits through the temporal bone from the brain and passes into the internal acoustic meatus and gets divided into two branches. Injury to the temporal bone can also cause damage to the vestibulocochlear nerve resulting in impairment of balance and hearing.
Noise pollution, such as exposure to loud music either over a period of time or suddenly, can cause nerve damage in the ear and result in hearing loss. Excessive and persistent noise damages the nerve endings present in the inner ear which can lead to permanent hearing loss. Nerve damage in the ear can also cause tinnitus, which is a condition where the patient feels persistent ringing in the ears.
Brain tumors or tumors of the skull can also cause damage to the vestibular or acoustic branches of the vestibulocochlear nerve. Acoustic neuroma is a noncancerous growth thought to occur as a result of genetic factors. This tumor can develop in vestibular portion of the nerve and is also termed as vestibular schwannoma. Some of the common symptoms of Acoustic neuroma include balance disorders, hearing loss and tinnitus.
Treatment of Nerve Damage in the Ear
Treatment depends on the cause of the nerve damage and can include the use of medications, surgery and hearing aids.
- Cleveland Clinic: https://my.clevelandclinic.org/health/diseases/9642-vestibular-schwannoma-acoustic-neuroma
- American Academy of Otolaryngology: https://www.entnet.org/content/acoustic-neuroma
- American Speech-Language-Hearing Association (ASHA): https://www.asha.org/public/hearing/Causes-of-Hearing-Loss/
- Johns Hopkins Medicine: https://www.hopkinsmedicine.org/health/conditions-and-diseases/vestibular-neuritis-and-labyrinthitis