Olfactory schwannoma.

We report a case of olfactory schwannoma with calcification. Intraoperative findings indicated that the tumour originated from the olfactory groove. Intraoperative findings of previous studies have not indicated a clear relationship between subfrontal schwannoma and the olfactory nerve, which seems strange, given the association between tumours and cranial nerves at other sites. We suggest this observation has not been reported because the growing olfactory schwannoma changes the local morphology, affecting the appearance of the olfactory nerve.