Technology that's music to her ears

Raleigh girl, 5, is one of the first to get a major cochlear upgrade

When Rachel Skergan was diagnosed with congenital deafness shortly after she was born, her parents made a choice that would alter her life: She would not be taught to sign with her hands or read lips.

Instead, they would rely on technology to allow her to hear and talk.

Rachel, now a chatty 5-year-old from Raleigh, received a cochlear implant in her left ear when she was 10 months and another in her right ear when she was 2 1/2. Weekly therapy sessions helped her interpret and reproduce sounds the implants generated, and her family took extra steps to improve her listening skills.

But still missing was music.

Rachel could hear melodies and beats. She could carry a tune, and she followed the beat when she danced, her mother Natalie Skergan said. Still, the details of music were missing -- the plinking of piano keys, the rat-tat-tat of a drum beat or the weeping of the strings in a full orchestra at play.

To capture those details, Rachel has become one of the first children in this country to be fitted with the latest cochlear technical upgrade: a speech processor that promises to improve the hearing of music.

The device was brought to market this summer by a small Durham company called Med-El. The privately owned Austrian firm, which put its North American headquarters in Durham because of the scientific expertise in the Triangle, is one of only three cochlear implant manufacturers in the United States.

In the more than 20 years since the Food and Drug Administration approved the first cochlear implant, microchips inside processors have gotten smaller and more powerful. That has improved the sound quality, but biomedical engineers are still working to capture the full range of musical sounds.

Med-El's technology, like that of the other manufacturers, digitizes the sound that is picked up and sent to the electrodes implanted in the patient's cochlea. Med-El claims its software allows it to better fine-tune the signal received by the patient.

Because music is such a complex sound, research now focuses on software that would allow an audiologist to better program a processor to each person's hearing damage, said Charles Finley, a biomedical engineer who teaches at UNC-Chapel Hill and N.C. State University. Finley was part of a group of Triangle researchers who in the mid-1980s came up with the multiple-electrode design that cochlear implants still follow.

"Every system has its limits," Finley said. "The same implant system can do remarkably well in one person and poorly in another."

Early implants are best

Technological limitations are partly why only half of the children who could benefit from a cochlear implant have one. Of about 38,500 Americans with cochlear implants, 15,500 received them as children, according to the most recent figures from the National Institute on Deafness and Other Communication Disorders.

The hearing of deaf children develops best with cochlear implants in place early on. The longer the auditory nerve isn't stimulated, the more likely it is that the brain uses nerve cells dedicated to hearing for other purposes -- a process that is difficult or impossible to fully reverse. The implications go beyond just being able to talk and listen. The ability to fully appreciate music has been linked to better math skills.

Cost -- an implant costs about $70,000 per ear, including surgery -- poor access to audiology and auditory-verbal therapy services and insufficient insurance reimbursements are also to blame, according to an April paper in a peer-reviewed medical journal.