An acoustic neuroma is a benign tumor of the cranial nerve that connects the inner ear and the brain. Though noncancerous and typically slow growing, it can affect both hearing and balance, and may cause hearing loss, tinnitus and dizziness. In rare cases, tumors may become large enough to press against the brain, interfering with vital processes and even leading to death.
What Causes Acoustic Neuroma?
A small percentage of acoustic neuromas are the result of an inherited disorder called neurofibromatosis type II (NF2), associated with a malfunctioning gene on chromosome 22. This genetic disorder often causes benign tumors to develop on the balance nerves on both sides of the head. More often than not, acoustic neuromas are classified as sporadic, meaning their exact cause is unknown.
There are no known risk factors for acoustic neuromas other than having a parent with NF2. If this is the case, children have a 50 percent chance of inheriting the condition themselves.
Signs of Acoustic Neuroma
Acoustic neuromas, sometimes called vestibular schwannomas, usually grow very slowly (or not at all). Because of this, symptoms early on are often difficult to spot. Patients may notice gradual hearing loss that is sometimes accompanied by tinnitus. If the tumor continues to grow, additional symptoms are likely to develop. These include dizziness and vertigo, facial numbness and weakness, a tingling sensation in the face, changes in taste, hoarseness, difficulty swallowing, headaches and confusion. Early diagnosis and treatment can help prevent more serious symptoms.
Detecting Acoustic Neuroma
The patient’s otolaryngologist can diagnose an acoustic neuroma primarily through a review of their symptoms in conjunction with a hearing test and imaging scans (MRI). Because growth of the tumor is usually very slow, many times the patient’s doctor will simply want to monitor the tumor’s progress over time, especially when few symptoms are present. Regular imaging tests every six to 12 months can track any growth.
Acoustic Neuroma Treatment
Tumors that are growing or causing symptoms generally require treatment. Gamma knife radiosurgery delivers radiation that stops the tumor from growing. Microsurgery is the other treatment option, particularly for large tumors with compression of the brain structures, tumors that are causing symptoms and in the interest of preserving hearing when tumors are small.
Our institution has a high volume acoustic neuroma program and performs all three surgical approaches for these tumors with particular expertise in hearing preservation. For more information, please call us at (720) 848-2800 or visit our acoustic neuroma clinic website.