Department of Otolaryngology - UT Memphis

The acoustic neuroma slowly grows in this canal and eventually may extend inward toward the brain. If the tumor grows large enough to press upon the brainstem, it will cause major problems. The most common complaint of a patient with an acoustic neuroma is hearing loss in one ear. Other symptoms include ringing in the ears, imbalance, spinning vertigo, numbness in the ear or facial area, and headache.

How is acoustic neuroma diagnosed?

A patient may be suspected of having an acoustic neuroma if a hearing test reveals sensorineural (nerve) hearing loss in one ear. It is important to note that most people with such hearing loss do not have an acoustic neuroma. Currently, the best way to diagnose an acoustic neuroma is with an MRI scan. This is an MRI scan showing an Acoustic Neuroma of the left vestibular nerve. This patient complained of diminished hearing in the left ear, and had no other problems. His audiogram showed mild nerve hearing loss on the left.

How quickly will an acoustic neuroma grow?
Acoustic neuromas are very slowl growing tumors. Growth is usually over several years. These tumors are benign- not cancer, and they will not spread to other areas. Symptoms are caused by pressure on nearby structures as the tumor grows.

What are the potential treatments for an acoustic neuroma?
The common recommendation for an acoustic neuroma is surgical removal, to prevent further neurological problems from future growth. A specialized form of radiation therapy is used in some cases. For some patients it may be best to give no therapy, and repeat the MRI scan after several months to determine whether the tumor is growing.

How are these tumors removed?
The tumors are removed by a team of surgeons, including a neurotologist and a neurosurgeon. This allows for the optimal access to the tumor and the most skilled resection of the tumor while avoiding complications. There are several approaches or ways for us to remove the tumor. If appropriate, hearing can be preserved in cases of small tumors in which the hearing in the affected ear is still functional. We typically utilize a middle fossa approach for hearing preservation. In this approach the neurosurgeon and the neurotologist combine to access the tumor within the bony canal from above. This approach allows for identification and preservation of the nerves and resection of the tumor.

If the tumor is large and/or if the hearing in the affected ear is not functional, then we utilize a translabyrinthine approach to remove the tumor. Utilizing this approach, the surgeons go through the inner ear and access the tumor and remove it. This offers a direct and rapid approach to tumor removal, however hearing is sacrificed with this procedure. Another surgical approach for tumor removal is the suboccipital route, in which the surgeons come from behind the ear to remove the tumor. This is a popular approach in many centers and can be performed as a hearing preservation approach or as an approach where hearing is sacrificed.

How long will I stay in the hospital after surgery?
Patients undergoing this surgery should anticipate being in the hospital between 5 to 7 days. In addition, they should plan to be off work for at least 3 to 4 weeks.

Do all tumors have to be removed?
No. Smaller tumors in the older patient (65 years or older) may not require any treatment at all. We know 35% - 40% of these tumors do not grow. Therefore, in these patients, we frequently advocate no surgery but rather repeating the MRI scan at regular intervals to assure that the tumor is not growing. If these scans confirm a lack of significant tumor growth, then the patient can be confident that this tumor will not cause them problems in their lifetime. Conversely, if the tumors grow significantly, then surgery can be undertaken.

What about radiation therapy for acoustic neuroma?
Radiation therapy has been advocated for the treatment of acoustic neuromas. This form of radiation therapy is referred to as the Gamma Knife or the Linear Accelerator (Linarc). Neither of these approaches cure the tumors, however radiation therapy can slow or stop tumor growth. The main advantage of this treatment is that it is quick, painless and involves no surgery. However this treatment does not cure the tumor, nor is it complication free. Facial paralysis, hearing loss, and numbness of the face, can occur after radiation therapy.

What are the complications of acoustic neuroma surgery?
The following represents a summary of the common potential complications of this surgery.

Hearing loss. The ability of surgeons to preserve hearing is related to the size of the tumor and the level of hearing prior to the surgery. Even when hearing preservation surgery is chosen, there is still a significant risk of total hearing loss in the affected ear. Spinning vertigo almost always occurs after surgery. This usually lasts for 2 to 3 days and is well controlled with available medication. The patients may have residual imbalance after the surgery and this will gradually improve over a period of weeks to months. It is important that the patient stays as active as possible after surgery to hasten their recovery.

Facial paralysis. A temporary paralysis of the face may occur after surgery, particularly with larger tumors. With very large tumors there is significant risk of permanent facial paralysis. This may require separate surgical intervention at a later date. Numbness of the face. In very large tumors the nerve supplying the sensation of the face may be affected.

Infection. Any time brain surgery is performed, there is risk of infection (meningitis). Patients are on antibiotics in the postoperative period to attempt to prevent infections. Should infection occur this is treated with intravenous antibiotics.

Spinal Fluid leak. The brain is lined in a cushion of fluid. When brain surgery is undertaken, there is always risk of leakage of this fluid through the wound. We are meticulous in our closure of the wounds to try to prevent this complication. This is almost always treated by bedside treatments and rarely, if ever, requires further surgery.