February 12, 2008

NEWS RELEASE

UNC Hospitals leads clinical trial of auditory brainstem implant in patients without tumors

Last July, surgeons at UNC Hospitals performed the first auditory brainstem implant procedure in the United States in a patient who did not have inner ear tumors associated with a condition called neurofibromatosis type II (NF2).

After several months of recovery, the patient who received the implant, 65-year-old Watson Hale of Morehead City, N.C., can now hear and understand speech to a limited extent and continues to improve.

“The big story here is that I was deaf as a door nail before the surgery,” Hale said recently, “and now I can hear.”

Hale’s hearing is still far below normal and he relies on lip reading to help him understand what others say to him. But for Hale to hear as well as he does now represents a huge step forward for him. Six years ago his hearing was normal, but he became completely deaf after contracting meningitis and spending several months in the hospital for that reason. Unfortunately, he did not benefit from a conventional cochlear implant because his hearing nerves were destroyed by the infection. After the auditory brainstem implant, Hale hopes that his hearing will continue to improve sufficiently for him to resume his work as a real estate appraiser.

His surgery was performed at UNC Hospitals on July 13 by Drs. Craig Buchman, professor of otolaryngology/head and neck surgery, and Matthew Ewend, chief of neurosurgery. It was the first in a new clinical trial to test the safety and effectiveness of the procedure in patients who have damaged auditory or hearing nerves but do not have NF2 tumors. Only two sites in the country currently are authorized to perform the procedure in this group of patients: UNC Hospitals and the House Ear Institute in Los Angeles.

The surgeons placed the electrodes from the auditory brainstem implant (ABI) through an opening in the back of the skull, in to an area of the brainstem that senses hearing. Collaborating with a team of audiologists, the electrodes were then stimulated and recordings from the brain were made. “Preliminary responses from the brain were very encouraging,” Buchman said. “A number of the stimulated electrodes generated neural responses that suggested that appropriate auditory stimulation was occurring. These were the kind of responses we were looking for and confirmed good placement of the device.”

The ABI was developed by the House Ear Institute in 1979 as a means of restoring hearing to NF2 patients who become deaf after surgery to remove tumors from their auditory nerves. The device was approved by the U.S. Food and Drug Administration in 2000 for use in this group of NF2 patients. It is not currently approved for use in patients without tumors, so the new clinical trial is aimed at obtaining FDA approval for use in non-tumor patients.

The ABI device works by bypassing the cochlea and the auditory nerves to transmit sound directly to the brainstem. The ABI is placed directly on the nerve center at the base of the brain. After the surgery, patients work with audiologists to test and adjust their wearable sound processors as they learn to understand and interpret new sounds. Most ABI recipients benefit through increased sound awareness, but must also use lip reading cues to understand speech.
The clinical trial seeks to enroll 3-5 patients at 2 sites.

ABOUT UNC HEALTH CARE

The UNC Health Care System is a not-for-profit integrated health care system owned by the state of North Carolina and based in Chapel Hill. It exists to further the teaching mission of the University of North Carolina and to provide state-of-the-art patient care. UNC Health Care is comprised of UNC Hospitals, ranked consistently among the best medical centers in the country; the UNC School of Medicine, a nationally eminent research institution; community practices; home health and hospice services in seven central North Carolina counties; and Rex Healthcare and its provider network in Wake County.