Schwannomas are usually located in the angle between the cerebellum and the pons, in the back of the skull (the posterior fossa).
Schwannomas are usually very slow-growing.
Common symptoms of Schwannoma are one-sided hearing loss and buzzing or ringing in the ear. Dizziness may also occur, although it is less common. If the tumor affects the facial nerve (the 7th cranial nerve, which is located next to the 8th cranial nerve), facial paralysis may occur. Other symptoms include difficulty in swallowing, impaired eye movement, taste disturbances, and unsteadiness.
Schwannomas account for about 8% of all primary brain tumors. They typically occur in middle-aged adults, and females are twice as likely as males to have this tumor.
Like many tumor types, the exact cause of Schwannoma is not known. However, it is believed to occur when there is a defect in a gene that normally prevents tumors from forming.
Total removal using microsurgical techniques is often possible. Stereotactic radiosurgery may be used as an alternative to surgery in some patients.