Neurofibromatosis type 2 [NF2] is an inherited disease which is mainly characterized by the development of multiple schwannomas and meningiomas. Incidence of the disease is about 1 in 60, 000.
Affected individuals inevitably develop schwannomas, typically affecting both auditory-vestibular nerve which lead in hearing loss and deafness. The majority of patients present with hearing loss, which is usually unilateral at onset and may be accompanied or preceded by tinnitus. Vestibular schwannomas may also cause dizziness or imbalance as a first symptom. Nausea, vomiting or true vertigo are rare symptoms, except in late-stage disease. NF II is caused by a defect in the gene that normally gives rise to a product called Merlin or Schwannomin, located on chromosome 22. Diagnosis is based on clinical and neuroimaging studies. Presymptomatic genetic testing is an integral part of the management of NF2 families. Prenatal diagnosis and pre-implantation genetic diagnosis is possible