Neurotology

Specialization on the parts of the brain and nervous system that relate to hearing and balance.

Auditory nerve

 

Neurotology, or neuro-otology, is a specialized area of otolaryngology, also known as ear, nose, and throat (ENT) medicine.

As the name ENT might suggest, an otolaryngologist is a medical specialist with extensive training in diseases and disorders of the – you guessed it – ear, nose, and throat. However, a neurotologist specializes one step further by focusing specifically on the parts of the brain and nervous system that relate to hearing and balance.

Another sub-specialty of otolaryngology is known as otology. Otologists are similar to neurotologists in that they deal with disorders of hearing and the ear, but do not have the specific training required to manage diseases that require specialized knowledge of the brain.

Another way of explaining it is that neurotology is the overlap between neurology (study of the brain and nervous system) and otology (study of the ear).

Conditions Managed by a Neurotologist

Neurotology is concerned with a number of neurological disorders of the ear, auditory nerve, and skull base. They can also be involved in managing facial injuries and hearing loss. Here are just some of the conditions that fall into a neurotologist’s arena.

Vertigo, dizziness, and balance disorders

This group of disorders encompasses over a dozen conditions, including Meniere’s disease, vestibular migraines, benign paroxysmal positional vertigo, superior canal dehiscence syndrome, and vestibular neuritis.

Symptoms of a balance disorder can include the sensation of dizziness or feeling like you (or your surroundings) are spinning. You may feel like you’re about to fall over (or you may indeed actually fall over). Some people experiencing an episode of imbalance or vertigo can also report lightheadedness, blurred vision, disorientation, anxiety and panic. Your heart rate and blood pressure may increase, and some people can also suffer nausea and vomiting.

Balance disorders can be caused by all sorts of things, including medications, head injuries, or even low blood pressure when standing up too quickly. However, often no underlying cause can be identified.

The treatment suggested by your neurotologist will vary depending on your diagnosis and what causative factors can be identified. For example, Meniere’s disease may be treated with lifestyle modifications or medications. In some cases, severe Meniere’s disease may require surgery, which can be performed by your neurotologist.

Cochlear implants

Hearing loss can range from mild to profound and be due to a variety of causes. In many situations, a hearing aid is sufficient to help the user regain functional hearing. However, sometimes, only a cochlear implant will do.

A cochlear implant differs from a hearing aid in that it entirely bypasses the ear and its structures and connects straight into the auditory nerve. Conversely, a hearing aid amplifies the sounds around the wearer.

Cochlear implants were first FDA-approved in the mid-1980s to treat deafness in adults but have since been approved for use in children over the age of 1 year old. These devices are surgically implanted by a neurotologist. One part of the device is attached to side of the head behind the ear, comprising of a transmitter, microphone, and receiver/stimulator, while an electrode array receiving electrical impulses from the stimulator is surgically implanted into the inner ear.

Though cochlear implants don’t mimic normal hearing, they allow the brain to recognize sounds from the environment as well as understand speech. Children who receive cochlear implants during their critical language development period have a much better chance of establishing normal language skills compared to children who don’t have timely access to this treatment.

Acoustic neuroma

An acoustic neuroma is a benign tumor that grows along the vestibular nerve that leads from your inner ear to the brain. Another name for an acoustic neuroma is a vestibular schwannoma, as this growth tends to develop from the Schwann cells that envelope the nerve fibers.

The symptoms of an acoustic neuroma may be difficult to identify, particularly in the early stages. However, as the growth enlarges, it can interfere with the function of nearby nerves in the face, blood vessels, or other parts of the brain. This can lead to symptoms such as:

  • Hearing loss, usually worse on one side
  • Tinnitus on one side
  • Dizziness
  • Balance difficulties
  • Loss of sensation or muscle control in the face

It’s not common for an acoustic neuroma to present a threat to life, but if it grows large enough, it may press on the brainstem.

Small tumors that demonstrate no or very slow growth can be monitored with regular scans and hearing tests. This management tends to be most appropriate for asymptomatic tumors or if more aggressive treatment would carry more risk than benefit.

If the acoustic neuroma is starting to cause problems, it can be treated with either surgery or radiation therapy to shrink or remove the tumor, whether partially or completely.

Tinnitus

Tinnitus is a phantom noise that only you can hear, without any external source. While most people describe their tinnitus symptoms as the sound of ringing, it can also present as clicking, roaring, buzzing, or hissing. Some people experience tinnitus for most of their waking hours, while for others it may come and go. Whatever the description, tinnitus can be a real bother and is related to anxiety, depression, and difficulties in concentration and memory.

The exact cause of tinnitus is still not fully understood, though it has been associated with noise damage, ear infections, Meniere’s disease, brain tumors, earwax, and certain medications. Tinnitus is known to be a neurological issue, possibly due to abnormal neural activity in the ear and auditory areas of the brain.

At this point in time, tinnitus doesn’t have a cure, but there are strategies to help tinnitus suffers better manage their condition. These treatments include:

  • Hearing aids to treat hearing loss associated with tinnitus. Many hearing aid devices are also fitted with a tinnitus masking function, which works to provide a background noise to make you less aware of the tinnitus
  • Counseling equips you with management strategies to cope with the effects of tinnitus. This can include techniques taught to relax and tune out the tinnitus, or even how to fall asleep effectively at night when tinnitus would otherwise keep you awake
  • Acoustic neural stimulation is a more novel treatment for very intrusive or persistent tinnitus. This device is worn like a pair of headphones, which play a broadband acoustic signal. The aim of this therapy is to modify your neural circuits to desensitize your awareness of the tinnitus
  • Antidepressants and antianxiety medications. If tinnitus is contributing to poor mental health, these medications can aid in lifting your mood and alleviating depressive or anxiety symptoms

The list of conditions treated and managed by a neurotologist goes on and on. It covers hard-to-pronounce words such as glomus tumors, cerebrospinal fluid leaks, otosclerosis, autoimmune inner ear diseases, mastoiditis, facial paralysis, and cholesteatoma, among others. If you’re experiencing symptoms relating to hearing, balance, your ears, face, or head, your first stop should be with your primary care family physician. After an assessment, your doctor can then refer you to the relevant specialist, such as an ENT doctor specializing in neurotology.