Washington, April 27 : A Loyola University Health System study has found that a device that produces tiny skull vibrations is highly beneficial for hearing impaired.
The researchers found that this system of conducting sound through skull bone is a big boost to people who are deaf in one ear and can't be helped by hearing aids or cochlear implants.
For the study, sixty Loyola patients were asked to compare their hearing before and after getting the system, called Baha.
Their ability to hear in a quiet environment improved by 28 percent, the trouble they had with background noise decreased by 33 percent and the difficulties they experienced with reverberating sounds in such settings as churches and lecture halls was reduced by 29 percent.
The only downside: there was a 7 percent increase in the annoyance caused by loud sounds such as fire truck sirens.
"People are hearing much better," said V. Suzanne Jeter, an audiologist at Loyola Oakbrook Terrace Medical Center.
Each year, more than 60,000 people in the United States become deaf in one ear due to such causes as chronic ear infections, congenital conditions, inner ear disease, injuries or tumors.
The study cited the example of Jim McGinn of Wheaton, who is completely deaf in his right ear, but can still hear from that side.
McGinn, a retired accountant, lost hearing on his right side due to an acoustic neuroma, a benign tumor in the inner ear. At the dinner table, he struggled to hear what people to his right were saying. And when driving his car, he couldn't hear the passenger.
A Loyola surgeon implanted a small titanium post in McGinn's skull, behind his right ear. The sound processor clips on to this post. The battery-operated processor is roughly the size of an adult thumb, from the tip to the first knuckle.
A microphone picks up sound waves, and a computer chip converts the sound waves into electrical signals that vibrate the skull. These tiny vibrations, which McGinn can't feel, travel to the inner portion of his left ear, where they are detected as sound. McGinn removes the sound processor when showering or sleeping.
"It's a dramatic difference. I'm getting conversation from around the table now, not just from the left side," McGinn said.
Since 2004, Loyola doctors have put the device in 130 patients. The total cost per patient ranges from 10,000 dollars to 15,000 dollars. Medicare and most insurance plans cover it, Jeter said.
Jeter presented the study at the 10th International Conference on Cochlear Implants and Other Implantable Auditory Technologies in San Diego.