High Fidelity

Audiologist René H. Gifford, left, adjusts the external sound processor worn by patient and study subject Ally Sisler-Dinwiddie, AuD’07. Having her cochlear implant remapped has made a huge difference in her quality of life, says Sisler-Dinwiddie. (Credit: John Russell)

Imagine hearing the words and tone of your dining companion in a crowded restaurant when once you heard overwhelming noise. Longtime cochlear implant users are now reporting dramatic improvements in hearing, thanks to Vanderbilt researchers.

“Our automated image-guided programming method can dramatically improve a person’s hearing with a cochlear implant, even if implantation happened a long time ago,” says Benoit M. Dawant, the Cornelius Vanderbilt Professor of Engineering and director of the Vanderbilt Initiative in Surgery and Engineering (ViSE).

More than 200,000 people worldwide have cochlear implants, and the number of newly implanted recipients is increasing rapidly. Although cochlear implants are considered standard-of-care treatment for severe to profound hearing loss, the quality of hearing is not on par with normal fidelity and recipients may experience only marginal hearing restoration. Users from the newly implanted to the long-term could experience better hearing with Vanderbilt’s new programming process.

Vanderbilt’s interdisciplinary research team drew on the work of students, professors and medical professionals from the School of Engineering, School of Medicine, Vanderbilt University Medical Center and Vanderbilt Bill Wilkerson Center. In addition to Dawant, the team included audiologist René H. Gifford, MS’97, assistant professor of hearing and speech sciences and audiology director of Vanderbilt’s cochlear implant program; Dr. Robert F. Labadie, professor of otolaryngology and associate professor of biomedical engineering; and then-graduate student Jack H. Noble, BE’07, MS’08, PhD’11, now a research assistant professor in electrical engineering and computer science.

The new automatic technique uses patients’ pre- and postoperative CT scans to determine the location of implanted electrodes and where overlap is occurring, possibly causing interference in the transmission of signals. The image-guided strategy and software, which Noble developed as a Ph.D. student, then pinpoint which electrodes can be turned off—thereby improving hearing fidelity. No surgery is required, and the process can be accomplished in one office appointment.

The project continues to enroll new study participants. Currently, adults are being recruited, although Gifford, who is also director of pediatric audiology at Vanderbilt, says she believes children in particular will benefit from the new programming because it can be mapped with or without responses from the patient.