March 17, 2010 - The FDA has approved Esteem, a fully implantable hearing aid with no visible external parts.
Esteem is approved for adults 18 and older with moderate to severe sensorineural hearing loss. This is the kind of hearing loss caused by genetic factors or by damage to the inner ear from noise, viral infections, or aging.
In a clinical trial, the device worked better than external hearing aids for 56% of patients, worked as well as an external hearing aid for 37%, and worked worse for 7%.
The most common side effects were caused by the surgery to implant the device in the inner ear. Over 40% of patients had a taste disturbance, nearly 20% had imbalance or dizziness, and 7% had facial paralysis. Most of these side effects got better within a year.
Another side effect may be wallet shock. The cost of the Esteem system is $30,000. Normal hearing aids range in price from several hundred to several thousand dollars.
But the Esteem system is radically different from hearing aids. It has three parts:
- The sensor detects vibrations coming into the ear and translates them to electric signals.
- The sound processor takes electric signals from the sensor and amplifies them to compensate for an individual patient's hearing loss.
- The driver receives these enhanced electric signals and turns them back into vibrations, which are transmitted to the inner ear and perceived by the brain as sound.
A possible drawback to the device is that the battery can be replaced only via a surgical procedure, which can be done under local anesthetic. The battery lasts about 4.6 years if left on 24 hours a day, 6.6 years if left on 16 hours a day, and nine years if left on eight hours a day.
The FDA approval has strings attached. Esteem maker Envoy Medical Corp. must conduct two studies: a follow-up study to see what happens to the 61 patients in the original study; and a new study of 120 Esteem recipients to assess the incidence of facial paralysis a month after implantation and safety five years after implantation.
"The approval of Esteem provides patients with an option to alleviate their hearing loss by using a device with no readily visible external components," Jeffrey Shuren, MD, JD, director of the FDA's device center, says in a news release.