Acoustic Neuroma

From WikiGenetics

1 Name of Condition
2 Definition
3 Description, Signs and Symptoms
4 Inheritance
5 Diagnosis
6 Treatment and Management
7 Prognosis
8 Resources
9 References

[edit] Name of Condition

Acoustic Neuroma, also referred to as: Acoustic neurilemoma, Acoustic neurinoma, or Vestibular schwannoma.

[edit] Definition

Acoustic neuroma is a benign tumor that develops on the cranial nerve that links the brain to the inner ear. While it is one of the most common forms of brain tumors, it is still rare, with about 1 in 100,000 cases estimated.

[edit] Description, Signs and Symptoms

As the tumor grows, it creates pressure against the cranial nerves associated with hearing and balance, thus causing the signs and symptoms of acoustic neuroma.

These symptoms include:

loss of hearing (typically gradual) on one side
ringing noise in the affected ear
loss of balance or dizziness
loss of feeling or tingling sensation in the face

[edit] Inheritance

While the actual cause of acoustic neuromas is currently unknown, there have been rare cases of tumors demonstrating neurofibromatosis 2, which is a genetic disorder involving the vestibulocochlear nerve and tumor growth. These patients have an aggressive form of acoustic neuroma on both sides of the nerve.

[edit] Diagnosis

Since most of the symptoms of acoustic neuroma are similar to those of more typical middle ear complications, the tumor is difficult to diagnose, especially during its early stages. Tests used to diagnose the condition are;

ear exams like the Brainstem auditory evoked response (BAER) to check hearing and neurological function
hearing tests given by audiologists
scans like magnetic resonance imaging (MRI) or computerized tomography (CT) of the head
balance function evaluation by way of a electronystagmography (ENG) test

[edit] Treatment and Management

Treatment for management of an acoustic neuroma involves: monitoring of the rate at which the tumor is growing, radiation to inhibit further growth of the tumor or surgery for removal.

[edit] Prognosis

With early detection and proper treatment, the prognosis is generally good, although long term-loss of hearing and tinnitus (ringing in the ear) are common. Facial numbness, balance difficulties, and headaches are typical in patients. Regrowth of a tumor is possible even with radiation or surgery, thus continual observation is important. For the small percentage of patients with the neurofibromatosis 2 genetic disorder, the prognosis is not as good due to the increased risks associated with having tumors on both sides (bilateral) rather than just one side (unilateral).