You may never have heard of acoustic neuromas. That’s because, although they can be debilitating, they’re also rare, affecting 2,000–3,000 people in the United States each year. We’re taking this opportunity to support Acoustic Neuroma Awareness Week by helping you learn about these rare tumors and how we treat them.
So what is an acoustic neuroma? You’ve heard the word “acoustic” before, probably describing a soft guitar sound or the quality of sound in a room. It means “related to sound or the sense of hearing.” A neuroma is a tumor that grows from a nerve. Put those together and an acoustic neuroma is a tumor that grows on the acoustic nerve, the nerve that runs from the brainstem to the ear and transmits information about sound and balance.
If it seems strange that an “acoustic” neuroma affects not only hearing but balance, you might be surprised to learn that our sense of balance is largely controlled by structures in the inner ear. These structures form the vestibular system, which allows us to sense gravity and motion. This is why sometimes an ear infection can make you feel unsteady on your feet.
Acoustic neuromas grow from the protective sheath of cells that surround the acoustic nerve. As these tumors grow they can compress the nerve, causing symptoms such as ringing in the ears, hearing loss, vertigo and balance problems. As the tumor grows larger it can press on other nerves that run between the brainstem and the face, resulting in facial numbness, headaches and nausea. In some cases these tumors can even cause hydrocephalus, a blockage of the flow of cerebrospinal fluid between the brain and spinal cord. When this fluid is blocked it builds up pressure and squeezes the brain, causing headaches, cognitive problems and trouble walking. Hydrocephalus is a serious complication and can be fatal if left untreated.
The good news is that these tumors are not cancerous and they grow slowly. This usually gives patients and neurosurgeons time to decide how best to treat the neuroma. In fact, for small tumors that aren’t causing symptoms, neurosurgeons often take a hands-off, wait-and-see approach.
But because these tumors are so rare, and because they’re in such a delicate area, not all hospitals and surgeons have experience treating them. It takes a great deal of practice and expertise to treat an acoustic neuroma without causing damage to the delicate facial nerves surrounding it.
Columbia neurosurgeon Dr. Michael Sisti is one of the few neurosurgeons with extensive experience in acoustic neuroma treatment. He has logged more than 30 years treating these rare tumors, and we can almost say he wrote the book on them, as he recently wrote the chapter on acoustic neuromas in the 13th edition of Merritt’s Neurology, a standard textbook for doctors studying the brain. In 2016 he was honored by the Acoustic Neuroma Association of New Jersey for his dedication to neuroma patients. His expertise is so well known that when Dr. Jose Nasser, a fellow neurosurgeon from Brazil, realized that he himself had one of these rare neuromas, he came immediately to Dr. Sisti for treatment.
Dr. Sisti has a few different approaches he uses to treat acoustic neuromas. If the tumor is too large to take a wait-and-see approach but is still smaller than 2.5 cm, Dr. Sisti may bring the patient in to Columbia’s Gamma Knife Center for radiosurgery. Gamma Knife uses precise beams of radiation that target the tumor while leaving the healthy structures around it untouched.
Radiosurgery treatment is usually short and relatively painless because the neurosurgeon does not have to make an incision or perform open surgery. The patient is sometimes able to go home that same day. Typically radiosurgery is done by attaching a special frame to the patient’s scalp which guides the surgeon to deliver gamma radiation to just the right spot. While this frame is more comfortable and less invasive than surgery, thanks to a recent upgrade of Columbia’s Gamma Knife some patients can even be treated without the frame. Our new Leksell Gamma Knife Icon system allows many patients to be treated with a comfortable facial mask instead. More than 500 acoustic neuromas have been treated with our Gamma Knife system, with excellent results. You can read more about a typical radiosurgical procedure here, and about our new Gamma Knife upgrade here.
In Dr. Nasser’s case, his acoustic neuroma was too large to be treated by radiosurgery. These larger tumors must be removed by open neurosurgery. Because neuromas can be located in delicate areas that affect facial sensation and movement, sight, hearing and fine motor control, it takes a great deal of skill to successfully remove them without damage. Dr. Nasser knew when he underwent his surgery that he was at risk of never being able to practice neurosurgery himself again. But thanks to Dr. Sisti, Dr. Nasser was able to return to his practice neuroma-free.
Dr. Sisti has had a great deal of success using both methods, surgery and Gamma Knife radiosurgery, to remove tumors while making sure the surrounding nerves in the face remain undamaged. Dr. Sisti and some of his colleagues recently studied 383 consecutive patients of Dr. Sisti to gather information about the safest and most effective way to treat neuromas. The results of the study made the cover of the Journal of Neurosurgery. Dr. Sisti and his co-author found that in many cases, using surgery to remove most of the neuroma and then following up with Gamma Knife radiosurgery to treat any remaining pieces of tumor brings the best results.
To learn more about the work Dr. Sisti and his colleagues are doing, follow the links below. Our neurosurgeons are always looking for better and safer ways to treat neuromas and all other brain tumors.
You have added pages to your clipboard. Please log in or create an account to share them or use later.
You are now being taken to Columbia Neurosurgery's site dedicated to the spine.
Use this button to save pages to your clipboard for future use.OK. Got it.