Results of Intraoperative ECochG During The Insertion of Two Types of Electrode Array: Slim Modiolar and Straight Electrode - OMAI 2018- The 10th International Symposium on Objective Measures in Auditory Implants

Angel Ramos de Miguel ¹ Christo Bester ³ Stephen O'Leary ³ Angel Ramos Macías ²

¹Acoustic and Balance Lab, Complejo Hospitalario Universitario Insular Materno-Infantil de Gran Canaria, Las Palmas, Spain
²Otorhinolaryngology - Head and Neck Surgery, Complejo Hospitalario Universitario Insular Materno-Infantil de Gran Canaria, Las Palmas, Spain
³Department of Otolaryngology, University of Melbourne, Melbourne, Australia

INTRODUCTION: Intraoperative, intracochlear electrocochleography (ECochG) will provide a means to monitor cochlear function and neural response during cochlear implant electrode insertion.

METHODS: Intracochlear ECochG was performed in 15 patients. The ECochG response was monitored from the apical-most electrode. The amplitude of the first harmonic was plotted and monitored in near real time by the audiologist-surgeon team during CI electrode insertion. 15 patients from 33 to 54 years old, with an average of 41 years . 8 of them were implanted with the CI532 and 7 the CI522 Cochlear AG. The different patterns in the insertion track were classified in Types A, B and C according to Harris et al (2017).

RESULTS: . 3 cases with no ECoG responses after cochlear approach were found with no residual hearing observed postoperatively. According to the in first harmonic amplitude change we found: 4 Type A ECoG response, all of them keep complete residual hearing at 6m postop. 5 Type B ECoG response (2 keep complete residual hearing at 6m potop and 3 drop of residual hearing was observed after 6m postop). 3 Type C ECoG response (In 2 cases some residual hearing drop observed after 6m postop and in 1 case complete residual hearing was observed at 6 m postop). No differences were found between CI532 and CI522 electrodes.

CONCLUSION: Three ECochG is a useful tool to evaluate the residual hearing in CI patients. More studies anr needed to achieved more knowledge regarding the relationship among ECoG and the presence of cochlear trauma, and functional outcomes.