ACOUSTIC NEUROMAS

Acoustic neuromas, also known as vestibular schwannomas, are non-malignant tumors of the 8th cranial nerve. They most commonly arise from the covering cells (Schwann cells) of the inferior vestibular nerve. They can also arise within the labyrinth. Acoustic neuromas account for approximately 6% of all intracranial tumors, about 30% of brainstem tumors and about 85% of all tumors in the cerebellopontine angle region.

Acoustic neuromas occur most commonly in adults.

Forms of Acoustic Neuromas
There are two forms: a sporadic form and a form associated with an inherited syndrome called neurofibromatosis type II (NF2). Almost 95% of all cases are sporadic. NF2 is very rare, affecting only several thousand adults in the United States.

Signs and Symptoms
Hearing loss occurs in almost 95% of patients with acoustic neuroma. About 90% present with a one-sided, slowly progressive hearing impairment. Sudden hearing loss occurs in about 10% of patients. Even a sudden hearing loss with complete recovery can be caused by an acoustic neuroma.

Diagnosis
The optimal test for excluding an acoustic neuroma is a gadolinium enhanced T1 MRI of the brain.

Treatment options
Medical management (observation)
Surgery
CyberKnife Stereotactic Radiosurgery

PITUITARY TUMORS

Most pituitary tumors are benign, grow slowly and do not metastasize; however, they can cause the pituitary gland to produce either too many or too few hormones. Symptoms are directly related to their growth in size and include headaches, vision problems, nausea and vomiting. In women, less frequent or no menstrual periods or no milk from the breasts are common symptoms. In men, loss of facial hair, growth of breast tissue, and impotence can be signs of a pituitary tumor. Diseases related to hormone abnormalities include Cushing’s Disease and acromegaly.  Cushing’s Disease is a disease that causes fat to build up in the face, back and chest, and the arms and legs to become very thin. Acromegaly is a condition in which the hands, feet and face are larger than normal. Pituitary tumors often go undiagnosed because their symptoms resemble those of so many other more common diseases.

Prognosis
If diagnosed early enough, the prognosis is usually excellent. If diagnosis is delayed, even a non-functioning tumor can cause problems if it grows large enough to compress the optic nerve, the brain or the carotid arteries. Early diagnosis and treatment is the key to a good prognosis.

Diagnosis
Diagnostic tools for a pituitary tumor include visual field examination, neurological exam, MRI with gadolinium and blood tests.

Treatment Options
Surgery
CyberKnife Stereotactic Radiosurgery