©

Hearing Systems
for Acoustic Neuroma Patients

Contents:

Before deciding on any hearing aid, please obtain the advice and guidance of a competent audiologist. Be certain that the audiologist is professionally certified and licensed by the state to practice audiology.

Originally contributed by Dick Barker.  Indented text is by AN patients.


BAHA Hearing Aid

BAHA (Bone Anchored Hearing Aid) is a revolutionary new system for helping people with single sided deafness (SSD);  it received clearance from the FDA in Sept. 2002.   It is manufactured by a European company called Entific (http://www.entific.com). Here are some facts about it:

  1. The device takes sounds and converts them to vibrational energy, sending them through the skull to the good ear, without involving the ear canal on either side. BAHA is made with Titanium, a metal which actually bonds with bone tissue at the molecular level (this is termed osseointegration), and the bone then acts as a pathway for sounds to travel.
  2. It requires a 30-60 minute surgery with a local anaesthetic, comparable to a dental procedure; the patient can go home immediately afterwards. 
  3. During this surgery, 3mm or 4mm titanium implant (a stud) is mounted on the skull behind the deaf ear. It take about three months for the implant to bond to bone tissue, after which it is connected to the sound processing device. This is a small digital device (about 5/8 inch by 1/2 inch by 1/4 thick). It just press fits onto the stud, and can be unclipped when you don't want to wear it. There are no devices in or around the good ear.  If a person is dissatisfied it can be removed.
  4. The ability to hear seems to improve with time.  That is, hearing is typically better at one year post placement than at 6 months post placement.  Some patients have reported that the BAHA has helped with tinnitus, while others reported no change.
  5. BAHA has been in a pilot market in France and the UK since 1999. To date 250 people have used this device for SSD, with 50% of them being AN patients. With BAHA, the sound can apparently be as good as in the good hearing ear. We have been told that even whispers become audible and comprehensible.
  6. Those with average bone threshold of 45 db or better can qualify for BAHA; a doctor's/audiologists exam is necessary to determine eligibility. There is a test strap (like a hair band) one can wear for a few days to determine if BAHA would be helpful. 
  7. The unit must be kept clean, and removed at night or during showers. There is a toggle switch that allows a person to focus on one on one, or for background. There is apporox. 3% complication rate, mainly from infections due to not keeping the unit clean.  

BAHA relies on the other ear to receive the vibrations that it transmits, and to translate them into sound. It is therefore appropriate for patients with unilateral hearing loss only. Many AN patients fall in this categority and may benefit from this device.

(6/03) I talked to the [BAHA] rep.  I am a 20-month post op surgery patient. I tried on the BAHA simulator and I was amazed how well it worked. I could hear again!!! The rep gave the figure of $7,000 to $10,000 and insurance may cover some if it.

(7/03) At the meeting [of our AN support group with a BAHA rep] a headset was passed around that gave the person an idea what it would be like.  One person stated that she could hear better with just the headset than the BI cross hearing aids that she wore to the meeting.  Some persons stated that there was a mechanical sound to it.  Most stated that it felt like they were hearing from the deaf side.

Both the unit and the surgery carry significant costs.

[I know a patient] who had the BAHA placed last spring.  He stated that a ball park figure would be $9000. - $10,000. for the surgical portion and a additional $5,000. for the unit.  His insurance paid...  Had he had to pay for it himself he's not sure that he would have paid this much.

Insurance coverage varies.  Some insurance companies will cover the surgery, but not the hardware, so it's important to make sure what is covered. Doctors must often provide a letter of medical necessity. We heard that Acoustic Neuroma patients are having an easier time obtaining coverage than persons who have lost hearing due to other reasons.  Be prepared to appeal if denied, a number of times perhaps. 

This device reminds us of a transcranial CROS hearing aid, which also used the skull as a path for the sounds to travel. However, with nothing implated into the skull itself, the quality of sound transmission for this older device was poor, which is why the newer generation of CROS hearing aids is wireless rather than transcranial.  It also reminds us of cochlear implants and auditory brainstem implants, which process the sound and translate it directly to electric signals which are sent though the implant, bypassing the damaged hearing structures in the ear. However, the sounds quality with these implants is not good, far from replacing the normal hearing as BAHA does.

Here is the site for BAHA hearing device users, run by UK patients.


CROS Hearing Systems

Wireless CROS (Contralateral Routing of Signals) systems are designed for individuals with little or no hearing in one ear, which is typically the case for acoustic neuroma patients. In the CROS system, sound is sent via from a microphone on the bad ear to a receiver worn on the good ear.  The latest systems are wireless, sending signal via radiowaves:

My right ear is deaf because of the Acoustic Neuroma and I wore a hearing aid in my left ear. Now with the new CROS unit I can hear on the right side! The unit behind the ear on the right side is really a radio transmitter that picks up sound on the right and transmits it to the left ear hearing aid. I can hear much better all around me now. I heard of a CROS hearing aid but I expected it to be a wire across my head. There may be such a system but it is not the one I have, which is manufactured by Telex. I am very pleased with the set up. 

The aid I have is called "model CIC", from the Lori Medical Laboratories... It was fitted by Dr. Aleo who is an audiologist.  This aid sends sound vibrations from my dead ear to my good ear without a wire. It has really improved my quality of life. The cost is between 500 an 1900 dollars depending on how small it is, smaller being less visible and more expensive.

I now am the proud owner of a Cros Aid. After 15 years of one-sided hearing, I am really enjoying actually hearing all the sounds around me. The best part was going through a drive-in and not having to turn around so my right ear could hear what was being said. What a difference it makes.

If the good ear needs amplification, there is a BiCROS system that uses a microphone on each ear and a receiver on the better ear. A combination unit with a user controlled switch is called a MultiCROS system. Depending on the circuitry needed, the cost of a wireless CROS system can range from $800 to $1100.

(by Ellen Farfel) I am writing to tell everyone about the new hearing system I am wearing. My right ear is deaf because of the acoustic neuroma and I wore a hearing aid in my left ear. Now with the new units (behind the ear type) I can hear on the right side! The unit on the right side is really a radio transmitter and picks up sound on the right and transmits it to the left ear hearing aid. I can hear much better all around me now. I heard of a cros hearing aid but I expected it to be a wire across my head. There may be such a system but it is not the one I have. The units are manufactured by Telex. I am very pleased with the set up and hope others benefit from the same thing.

Telex Communications, Inc., of Minneapolis, MN, is a manufacturer of CROS systems. In promotional materials, Telex describes benefits and limitations of the CROS systems:

Benefits

Limitations

  1. The user can hear sounds more easily without having to turn the better ear towards the sound.
  2. Easier listening means less stress & fatigue.
  3. Extra cues are provided for locating sound.
  4. A sense of sound balance is restored. 
  1. Background noise is not eliminated.
  2. All sound is sent to one ear; no true binaural hearing.
  3. Directional assistance is limited.
  4. Radio signal is subject to electrical interference.
  5. User may need two different battery sizes for the unit.
  6. User needs to wear two instruments.

Digital Hearing Aids

Fully digital hearing aids became available in the U.S. about three years ago. These are, in effect, miniaturized computers that can be programmed to meet individual needs and adjust automatically to changing levels of sound in the environment. "In a conventional hearing aid, sound enters the hearing aid, is made louder, and then is delivered to the ear. [In digital hearing aids], "sound is picked up by a microphone, but instead of being sent to an amplifier it is sent to a converter that digitizes the sound (This means turning the sound into a series of O’s and 1's, a binary signal, a signal that can be delivered to a computer). This digitized sound can be manipulated according to the computer program designed to meet the specific needs of the user before it is sent to the receiver and on into the wearer’s ears." Digital hearing aids come in many styles, and reports are that they are very good. Annoying feedback and background noise can be greatly reduced. But digital aids are expensive, and just because they are digital does not mean they will be the best choice for everyone over the conventional aids and programmable analog aids that have been available for many years. Selecting the proper hearing aid is something that an individual patient needs to decide after being tested by and with the advice of an audiologist.


Assistive Listening Devices (ALDs)

A hearing aid is not always the answer to a hearing loss. Also available today are many types of assistive listening devices, ALDs. In contrast to hearing aids, which are general purpose hearing devices that make all sounds louder, ALDs are designed to increase the loudness of a desired sound, while minimizing or eliminating background noise. For example, one useful system employs a compact transmitter (microphone) that can be placed near a speaker at a meeting or in a classroom to send the speaker’s voice directly to your headset receiver (earphones). There are also systems for listening to TV, radio or stereo, and special amplifying devices that attach to telephone receivers. Most have volume control dials. For anyone considering an ALD for personal use, the American Speech-Language-Hearing Association (ASHA) recommends seeking the help of an audiologist to determine which device is best. For more information on ALDs, write to:

ASHA
Consumer Affairs Division
10801 Rockville Pike, Rockville, MD 20852
(1-800-638-8255)


Cochlear Implants

The cochlear implant is an electronic device which restores partial hearing to a totally deaf ear, appropriate only for those who "are unable to understand speech even with powerful hearing aids" in one or both ears.  This device replaces the work of hair cells in the temporal bone (cochlea) in the inner ear, when the hair cells do not work but the hearing nerve does.   Those AN patients who have completely lost their hearing as a result of the tumor's growth often fall in this category; AN patients with partial hearing loss, or those with a severed hearing nerve, are not candidates for cochlear implants.

The cochlear implant consists of a sound processor worn in the ear, which translates sounds into electrical signals, and electrodes, which are implanted directly into the cochlea to transmit these signals directly to the hearing nerves. A public service leaflet of the American Academy of Otolaryngology - Head and Neck Surgery, Inc., notes: "Part of a cochlear implant is surgically implanted in the ear (temporal bone) and part is worn externally like a hearing aid. However, a cochlear implant is not a hearing aid in the sense of making sound louder or clearer. It is a medical device which bypasses damaged parts of the inner ear and electronically stimulates the nerve of hearing."

The cochlear implant does not restore normal hearing, but it can help the wearer -- with proper training -- understand speech and perceive sounds from the environment.  The House Ear Institute observes: "It is the patient who becomes deaf (after they learn to talk) who is most likely to benefit significantly from the cochlear implant. The work of implant investigators over the last 30 years has shown that the implant provides, among other things, an awareness of environmental sounds, improved speechreading, and usually at least some speech discrimination.  Full speech discrimination, however, is not yet possible."  

The latest research shows that receiving a cochlear implant to restore hearing dramatically increases the risk of developing bacterial meningitis.

There is active research to improve cochlear implant technology.  It is hoped that sometime in the future, it will be possible to provide a perfectly working "electronic ear" to those whose natural ear is no longer works.


Auditory Brainstem Implant

Auditory Brainstem Implants (ABIs) have been approved by the FDA in 2000. They can restore hearing for patients who are deaf as a result of AN surgery, when their hearing nerve became damaged or severed.  It is the first hearing-assisting device that is implaned directly in the brain:

Removal of tumors often requires severing the auditory nerves. With the nerves cut, electrical signals from the ear cannot reach the brain, which causes deafness. The ABI device is implanted in the brain where it electrically stimulates an area that normally receives signals from the ear. A pocket-sized speech processor, worn by the patient, picks up sounds, changes them to electrical pulses and relays the pulses to the device.

ABI is installed at the time of tumor removal, and are an important consideration when removing a tumor from the only hearing ear, such as for NF2 patients. Results are varied.  Some users find it very effective, once they get used to it; some have reported that they even use it on the telephone. Others report less successful results, but any hearing whatsoever is very important to those who otherwise would have none.

ABIs are made by the Cochlear Corp. of Englewood, CO (http://www.cochlear.com); the full device name is "Nucleus 24 Multichannel Auditory Brainstem Implant".  ABI is not to be confused with cochlear implants, which are for cochlear problems as opposed to nerve problems. 


Paying for hearing aid

Medicare does not pay for hearing aids; insurance sometimes does.  When hearing aid is not covered by insurance, other sources may be available for those who are still working. 

My insurance HMO would not pay for my hearing aid, but my doctor put me in touch with the Department of Vocational Rehabilitation since my job relied on the telephone. They paid for the whole thing and even said they would pay for head set if I wanted. They were very nice to work with and I couldn't believe they took care of it for me. I live in Kentucky, so I don't know what the organization would be called in your state, but maybe your hearing doctor could help you out there.

My regular HMO did not cover it, but I had a re-imbursement from work for part of the cost.

Being on Medicare - no they won't pay for hearing aids. But your state rehabilitation department will pay for them as long as a person is still working and can qualify on the salary. 

©

Last Edited: Wednesday, November 19, 2003