NF2 and NF2-related schwannomatosis: Sporadic CVS are caused by somatic mutation within vestibulocochlear nerve Schwann cells [4], whereas NF2-related schwannomatosis, formerly neurofibromatosis type 2 or NF2 [5,6], is caused by systemic mutation in the NF2 gene on 22q12.2 [4,7,8].