What is it?
An acoustic neuroma is a non cancerous tumor which is located on the vestibular nerve. In most cases, the tumor grows very slowly, or not at all.
Causes
Acoustic neuromas occur due to a faulty gene on chromosome 22. Normally, this gene produces a tumor suppressor protein that helps control the growth of Schwann cells covering the nerves. When this does not occur, a slow growth occurs on the nerve.
Symptoms
The vestibular nerve transmits information related to our balance and hearing. For this reason, a tumor on this nerve often results in an increased sense of imbalance, hearing loss, and ringing in the ears.
Diagnosis
Due to the slow growth of these tumors, initial symptoms tend to be very mild. For this reason, acoustic neuromas are often difficult to diagnose in the early stages. The preferred method of diagnosing an acoustic neuroma is through imaging – usually an MRI. The MRI can detect tumors as small as 1 mm in diameter. If an MRI is not appropriate, a CT scan may be ordered, although it is not able to detect small tumors. A hearing test may also be ordered to assess the ability of each ear to determine sound tones and frequencies.
Treatment
Treatments for acoustic neuromas vary depending on the size and growth of the tumor, overall health and the intensity and frequency of symptoms. Possible treatment options include monitoring the growth, vestibular/balance physical therapy, surgery, or radiation.
1. Monitoring
Simply monitoring the tumor is an option if the neuroma is small, isn’t growing or is growing slowly, and causing few or no signs or symptoms. Monitoring includes regular imaging and hearing tests, usually every six to 12 months, to determine if treatment is required at any point.
2. Vestibular Therapy
Vestibular Therapy is a specialized branch of Physical Therapy which specifically treats vestibular disorders. Your doctor may recommend Vestibular Therapy if your acoustic neuroma is causing symptoms such as balance problems, or dizziness. Through specialized exercises, physical therapy can help compensate for the damage caused at the vestibular nerve.
3. Surgery
If the tumor is large and causing symptoms which are having a significant impact on your quality of life, surgery may be required. The surgery, of which there are several techniques is performed under general anesthesia. The type of surgery is determine by the size of your tumor and the effects on hearing. The aim of the surgery is to remove all of the tumor if possible, along with avoiding damage to the facial nerve.
4. Radiation
For older adults who are not good candidates for surgery, and if the tumor is small, radiation may be an appropriate treatment. Images are taken to determine the exact location of the tumor, and gamma rays with a specific amount of radiation are then delivered to the tumor. The goal of radiation is to stop the growth of a tumor and preserve the facial nerve’s function to prevent facial numbness or paralysis.