Neurofibromatosis type 2 (NF2) is much less common than NF1, affecting about 1 in 25,000 people worldwide regardless of sex or ethnicity. The disorder is characterized by the development of benign tumors called vestibular schwannomas (also called acoustic neuromas) on the nerve that carries sound and balance information from the inner ear to the brain (the eighth cranial nerve). These tumors, which affect both ears, often lead to partial or complete hearing loss. NF2 can also cause schwannomas to develop on other cranial or peripheral nerves as well as other tumors such as meningiomas (tumors of the membranes surround the brain and spinal cord) and ependymomas (tumors that develop from cells that line the ventricles of the brain and center of the spinal cord). The disorders can also cause the development of cataracts, potentially compromising vision.
While most people develop symptoms in the late teens and early adult years, about 10 percent of people develop symptoms during late childhood. The most common symptoms of NF2 include ringing in the ears (tinnitus), gradual hearing loss, and balance problems.