The efficacy of Electric Acoustic Stimulation for partial deafness: first clinical results in Japan

Abstract

Objective: To evaluate the efficacy of Electric Acoustic Stimulation (EAS) for high frequency hearing loss patients in Japan, and to determine the effect of EAS in individuals with residual lower frequency hearing, on speech perception in quiet and noisy condition. Study Design: Prospective design. Patients and Methods: Nine patients with profoundly high frequency hearing loss were recruited. All patients were assessed with an audiological test battery, and underwent cochlear implantation with a round window approach using the MED-EL FLEXeas electrode. Residual hearing, Japanese monosyllable words and speech discrimination abilities were evaluated at the point of 1, 3 and 6 months after EAS activated. Results: There were no cases with complete hearing loss in residual hearing after implantation. Low frequency residual hearing was preserved in eight patients, and one patient with a loss of residual hearing benefited from electrical stimulation. All EAS patients showed significant efficacy on all audiological tests over time. Conclusion: At the lower frequency hearing preservation with cochlear implant can be possible by round window approach as atraumatically surgical technique and FLEXeas electrode. AS the results with EAS demonstrate that this newly devise is effective in Japanese speaker with high frequency hearing loss.