More is Better: Cochlear Implants

By Vivian Richardson, Ivanhoe Health Correspondent

ORLANDO, Fla. (Ivanhoe Newswire) -- One cochlear implant can change the world for someone with significant hearing loss. Now, researchers say two cochlear implants, devices that transmit sound signals to the brain, can make an even bigger difference.

Children with two cochlear implants are better able to understand speech and locate the source of different sounds, according to researchers from the University of Wisconsin-Madison. In a study of 55 deaf children who received a second implant several years after their first, investigators report the children were able to adapt to two-sided hearing over time, as it takes time for the brain to adjust to two sound signals.

"Using two ears helps with you with acoustic functions in complex environments, such as when you're trying to listen to important sounds in noisy environments or when you're trying to localize sounds," Ruth Litovsky, Ph.D., told Ivanhoe. As an expert in binaural hearing, or hearing with two ears, Dr. Litovsky wanted to know more about the actual benefits of having two cochlear implants.

The children in Dr. Litovsky's study all received their second implant years after their first surgery. The delay between implants may make adjusting to hearing on two sides a longer process. "From what I hear from a lot of surgeons, nowadays they are able to put both implants in at the same time without too much difficulty," Dr. Litovsky said, though she added there is not a lot of data to indicate which choice is clearly better.

Otologist Joseph Roberson, M.D., from the California Ear Institute in Palo Alto, Calif., recommends two implants to his patients.

"I think the bottom line question is, 'What would I do with my own child,'" said Dr. Roberson. "I would definitely have two implants." Some restrictions do apply, however. Both ears must be anatomically able to support an implant. For some people, Dr. Roberson explained, a cochlear implant in one ear combined with a hearing aide in the other would work best.

It is unusual for patients receiving cochlear implants to get more than one. Dr. Litovsky estimates only about 3 percent of the about 100,000 people with cochlear implants have two. Some insurance companies will only cover the cost of one implant, which can be as much as $50,000.

This article was reported by Ivanhoe.com, which offers Medical Alerts by e-mail every day of the week. To subscribe, click on: http://www.ivanhoe.com/newsalert/.

SOURCE: Ivanhoe interview with Ruth Litovsky, Ph.D., and Joseph Roberson, M.D.; 30th Annual Midwinter Meeting of the Association for Research in Otolaryngology in Denver, Feb. 10-15, 2007