Bilateral Vestibular Schwannoma
Bilateral vestibular schwannomas affect both hearing nerves and are usually associated with a genetic disorder called neurofibromatosis type 2 (NF2). Half of affected individuals have inherited the disorder from an affected parent, and half seem to have a mutation for the first time in their family. Each child of an affected parent has a 50 percent chance of inheriting the condition.
Unlike people with a unilateral vestibular schwannoma, individuals with NF2 usually develop
symptoms of vestibular schwannoma in their teens or early adulthood. In addition, people with NF2 usually develop multiple brain- and spinal cord-related tumors. They can also develop tumors of the nerves associated with:
- Swallowing
- Speech
- Eye and facial movement
- Facial sensation.
Determining the best way to manage bilateral vestibular schwannomas as well as the additional nerve, brain, and spinal cord tumors is more complicated than deciding how to treat a unilateral vestibular schwannoma. Further research is needed to determine the best treatment for individuals with neurofibromatosis type 2.
Causes of Vestibular Schwannoma
No one knows the exact cause or causes of vestibular schwannoma. Doctors cannot always explain why one person gets the condition and another does not. However, research has shown that people with certain risk factors for this condition are more likely than others to develop it. A risk factor is anything that increases a person's chance of developing a disease.
Specific vestibular schwannoma risk factors include:
- Age (the tumor most often appears in people between the ages of 30 and 60)
- Family history of neurofibromatosis type 2.
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