Objective: This study is designed to test the hypothesis that preservation of residual hearing in a pediatric population is possible using standard electrode arrays with full-length insertions. Surgical technique during implantation also is described.
Study Design: Retrospective review of patient medical records.
Setting: Academic tertiary care center.
Patients: Thirty-one severely to profoundly hearing impaired pediatric patients with some residual hearing precochlear implantation.
Intervention: Cochlear implantation using a modified "soft surgery" protocol.
Main Outcome Measures: Preimplant and postimplant pure tone thresholds and pure-tone average were calculated from unaided preoperative and postoperative audiograms from 250, 500, and 1,000 Hz. Hearing preservation rates were determined to be complete (loss of ≤10 dB), moderate (loss of 11-20 dB), marginal (loss of 21-40 dB), or none (loss of >40 dB or no response at the limits of the audiometer). Functional residual hearing rates (defined in this study as at least 1 threshold better than or equal to 75 dB HL for 250, 500, or 1,000 Hz were calculated.
Results: Complete hearing preservation was achieved in 14 (45.2%) of 31 patients, whereas 28 (90.3%) of 31 had at least partial hearing preservation (loss of ≤40 dB). The preoperative to postoperative low-frequency pure-tone average had a mean change of 18.5 dB and median change of 20 dB. Of the patients who had preoperative functional hearing, 9 (50.0%) of 18 maintained functional residual hearing postoperatively for at least 1 pitch.
Conclusion: Preservation of residual hearing is feasible in pediatric cochlear implant patients using standard-length electrode arrays with full insertions. These data have implications for cochlear implantation in pediatric patients who are at higher risk of progressive hearing loss than adults.
Departments of *Otolaryngology-Head and Neck Surgery, and †Anatomy and Neurobiology, ‡Program in Audiology and Communication Sciences, Washington University School of Medicine; §Cochlear Implant Program, Saint Louis Children's Hospital; and ∥Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri, U.S.A.
Address correspondence and reprint requests to Richard A. Chole, M.D., Ph.D., Department of Otolaryngology-Head and Neck Surgery, Washington University School of Medicine, Campus Box 8115, 660 South Euclid Avenue, St. Louis, MO 63110; E-mail: firstname.lastname@example.org
Supported by grants NIH/NIDCD R01 DC000263 (RAC) and NIH/NIDCD K08 DC 006869 (TEH).