As discussed above, a radiological phenotype of bilateral IAM schwannomas relating to the eighth cranial nerves is pathognomonic of an underlying diagnosis of NF2 rather than the presence of a sporadic eighth nerve schwannoma.8 Additionally, we now suggest that the presence of an apparently isolated multifocal vestibular schwannoma should raise the strong possibility that the individual has a form of NF2. This evidence concerns the gene NF2 and schwannoma.