The University of Minnesota announced today that it will lead a $9.7 million grant over the next five years from the National Institutes for Health (NIH) BRAIN Initiative to develop a new implantable device and surgical procedure with the goal of restoring more natural hearing to people who are deaf or severely hard-of-hearing.
The international team is made up of engineers, scientists, surgeons, and medical researchers from three countries that span three universities. The team also includes researchers from two medical device companies.
Since the mid-1980s, the cochlear implant has been used to treat deafness. The device consists of an electrode array that is implanted in the bony, snail-shaped structure in the ear, called the cochlea, to stimulate the auditory nerve that projects to the brain. According to the National Institutes on Deafness and Other Communication Disorders, the number of people who use cochlear implants keeps growing. More than 324,200 people across the world have cochlear implants. In the United States, more than 96,000 people have cochlear implants, which includes about 38,000 children.
Cochlear implants have been proven to be an effective treatment option in many people with hearing loss caused by a lesion or disease of the inner ear or the auditory nerve. However, certain individuals cannot benefit from a cochlear implant due to specific anatomical variations in the cochlea that limits the ability to implant the device or sufficiently activate the auditory nerve. In addition, cochlear implants are positioned within the cochlea and transmit electrical current across the bony cochlear wall to reach the auditory nerve. Not all of the intended current reaches the auditory nerve in a focused manner.
The vision of this new grant project is to implant an electrode array directly into the auditory nerve. This approach not only provides access to the hearing pathway for those who cannot be implanted into the cochlea, but may also improve activation of the auditory pathway to the brain that could be helpful for hearing in noisy environments and music.
"We hope that our proposed auditory nerve implant could lead to a new generation of neural technologies and greatly advance novel treatment options in the hearing implant industry," said Hubert Lim, the lead researcher on the grant and an associate professor in the University of Minnesota's Department of Biomedical Engineering in the College of Science and Engineering and Department of Otolaryngology in the Medical School.
In the first three years of the grant, the team will develop the technology and surgical approach as well as assess the safety and functionality of the auditory nerve implant in pre-clinical studies. During the last two years of the project, the researchers will implant devices in up to three deaf patient volunteers who cannot sufficiently benefit from cochlear implants due to anatomical reasons.
"Work to develop brain or intracranial solutions beyond the cochlear implant is getting more attention in recent years," Lim said. "This is an exciting time with many new advancements in nerve and brain technologies across the neuroscience community. Although we are still many years out before such solutions become widely integrated into treatment options for hearing conditions, I'm honored and optimistic that our team is working on novel technology that one day may be able to achieve more natural hearing, such as hearing in noisy environments or the intricacies of music."