Individuals with partial hearing loss may benefit from hybrid cochlear implant

Jan 11, 2011

Hearing loss can affect anyone, at any time. But it can be especially frightening for someone who suddenly starts to lose his hearing during adulthood. Tom Groves, 77, first noticed his diminishing hearing when he was in his early 40s. He was unable to hold conversations with large groups of people; found it nearly impossible to socialize in high-background noise environments like restaurants; and couldn't enjoy radio, TV and movies unless they were captioned. Now, Groves is hearing much better than he has in 30 years, thanks to an experimental hybrid cochlear implant.

Northwestern Memorial Hospital is one of nine centers in the U.S., and the only in Illinois, that is participating in a study investigating the effectiveness of a new cochlear implant device that aims to restore hearing for individuals with high-frequency hearing loss and functional low-frequency hearing.

This group of patients doesn't meet the criteria for conventional because they have near perfect residual hearing in low pitches that allows them to perform well on tests used to determine candidacy for traditional implants. However, their hearing in high pitches is so poor that a hearing aid is not helpful, making them ideally suited for the hybrid implant which addresses both issues.

"We are hopeful that the hybrid cochlear implant will provide a subset of people who were previously not candidates for an the opportunity to test the device to determine if they can experience sound again," said Northwestern Medicine neurotologist Andrew Fishman, MD, principal investigator of the study, staff in the departments of and neurosurgery at Northwestern University's Feinberg School of Medicine, and Mr. Groves' cochlear implant surgeon. "The potential for patients with a significant amount of residual hearing, but a large amount of high-frequency hearing loss, to have an alternative to would be a great improvement to what is currently available."

Cochlear implants were FDA approved in 1984 as a treatment option for restoring hearing in people with severe and profound . The surgical implant system is designed to stimulate the auditory nerve by bypassing damaged parts of the ear. A small battery-operated mini "computer" and microphone are worn on the outside of the ear and convert sounds into electric signals. The signals are then transmitted to implant electrodes in the cochlea, which stimulate the nerve endings so sound can be perceived by the brain.

The hybrid cochlear implant works in the same way as traditional cochlear implants, stimulating nerve endings in the cochlear so that high-pitched sounds can be heard. In addition, it also involves amplification for low-pitched sounds, similar to a hearing aid. Like traditional cochlear implants, the hybrid version is worn outside the ear and converts sounds into acoustic and electric signals.

"The surgical implantation of cochlear devices is typically done on an outpatient basis, and usually with non-serious complications, aside from mild discomfort following surgery," said Northwestern Medicine otolaryngologist Alan Micco, MD, co-investigator of the study and chief of otology/neurotology at the Feinberg School of Medicine. "A few weeks following surgery, the activation process and fine-tuning take place to determine what audio thresholds work best for the individual, and sounds can usually be perceived shortly thereafter."

Post-activation evaluations take place at three, six and 12 months following the initial activation process to assess progress of the cochlear implant. An audiologist will also test the implant to determine if participants are able to understand words, sentences in noisy and quiet environments, as well as music recognition.

A few months post-surgery, Groves is happy to have some of his hearing restored. "I'm very excited and encouraged by my experience with the implant. I know I'm hearing better than I have for many, many years and for that I'm very grateful."

Explore further: US scientists make embryonic stem cells from adult skin

add to favorites email to friend print save as pdf

Related Stories

MRI machines may damage cochlear implants

Dec 01, 2008

Patients with cochlear implants may want to steer clear of certain magnetic imaging devices, such as 3T MRI machines, because the machines can demagnetize the patient's implant, according to new research published in the ...

Cochlear implants slightly less beneficial in older patients

May 17, 2010

Older adults appear to benefit significantly from cochlear implants, but not as much as younger patients who had similar levels of hearing impairment before surgery, according to a new study by researchers at The Medical ...

Recommended for you

Leeches help save woman's ear after pit bull mauling

Apr 18, 2014

(HealthDay)—A pit bull attack in July 2013 left a 19-year-old woman with her left ear ripped from her head, leaving an open wound. After preserving the ear, the surgical team started with a reconnection ...

New pain relief targets discovered

Apr 17, 2014

Scientists have identified new pain relief targets that could be used to provide relief from chemotherapy-induced pain. BBSRC-funded researchers at King's College London made the discovery when researching ...

User comments : 0

More news stories

Cancer stem cells linked to drug resistance

Most drugs used to treat lung, breast and pancreatic cancers also promote drug-resistance and ultimately spur tumor growth. Researchers at the University of California, San Diego School of Medicine have discovered ...

Making graphene in your kitchen

Graphene has been touted as a wonder material—the world's thinnest substance, but super-strong. Now scientists say it is so easy to make you could produce some in your kitchen.