The auditory (eighth) nerve neuroma is a benign tumor of the nervous system that is located in the part of the brain through which the auditory nerve passes. The symptoms of the auditory nerve neuroma are not specific, which may delay an accurate diagnosis. What are the causes and symptoms of an acoustic neuroma? What is the treatment?

Auditory nerveis otherwise a tumor of the VIII nerve orneuroma of the eighth nerve(vestibulocochlear), i.e. the nerve of the two sensory organs - hearing and balance. An auditory neuroma comes from cells that make up the nerve sheath called Schwann cells.

The auditory neuroma belongs to the group of tumors of the cerebellopontine angle (these are tumors of the central nervous system) and is the most frequently diagnosed (80-90% cases) neoplasm of this type. Other diagnosed tumors of the post-cerebellar angle are cholesteatoma, meningiomas, as well as ( although rarely) hemangiomas, teratomas and lipomas.

Auditory neuroma - causes and risk factors

Tumors of the VIII nerve on one side are acquired disease, while neuromas that occur on both sides are hereditary and are a symptom of type 2 neurofibromatosis.

Auditory neuroma occurs in 1 in 100,000 people annually

The causes of the acquired disease are unknown, but the factors that increase the risk of its development include:

  • smoking
  • epilepsy diagnosed at least 10 years ago
  • for women - giving birth to a child

Auditory neuroma - symptoms

As a result of pressure on the structures of the brain by a growing tumor, symptoms such as:

  • mono- or asymmetric sensorineural hearing loss that progresses gradually over months or years and is most often high-frequency. Sudden deafness is very rare. Hearing remains normal in a small percentage of patients (even with a large tumor)
  • tinnitus - usually constant, one-sided, high-frequency. Noises covering low frequencies or periodically appearing are less frequent
  • imbalance - usually there is feelings of instability or loss of balance. Common bouts of vertigo withspinning sensation, nausea and vomiting

Some patients may develop nerve paresis:

  • facial - remains almost unnoticed by most patients
  • trigeminal - initially there is tingling and numbness in the middle, upper and lower parts of the face, burning of the tongue, loss of sensation in this area, and eventually weakness and atrophy of the masticatory muscles.

Unusual symptoms such as taste disturbance, sore throat or sore eye, dry eye, headache, and vomiting of unclear cause usually indicate late disease.

Auditory neuroma - diagnosis

If a neuroma of the auditory nerve is suspected, audiological tests are performed (including tonal and verbal audiometry and brainstem evoked potentials - ABR), electronystagmography, i.e. balance organ examination, and imaging tests - temporal bone tomography, magnetic resonance imaging the posterior fossa of the skull with Gd-DTPA contrast (an alternative is FSE-MRI, or fast spin echo MRI). A three-dimensional reconstruction can also be performed, which enables an accurate assessment of the structures of the central fossa of the skull.

Auditory neuroma - treatment and surgery

Treatment consists in the complete removal of the tumor, but care must be taken to maintain neurological functions. In some cases, it is possible to choose radiotherapy or be limited only to radiological observation (in the case of slowly growing tumors).

Category:

Oncology