Type of Electrode Insertion and Hearing Preservation Outcomes

• Published in: Otolaryngology-head and neck surgery 2011-08, Vol.145 (2_suppl), p.P104-P104
• Main Authors: Rivas, Alejandro, Forero, Victor H., Rivas, Adriana, Haynes, David S., Rivas, Jose A., Wanna, George
• Format: Article
• Language: English
• ISSN: 0194-5998; 1097-6817
• DOI: 10.1177/0194599811416318a200

Objective: Assess the levels of hearing preservation during cochlear implant surgery by comparing different electrode insertion techniques (standard cochleostomy, soft surgery, round window). Method: Retrospective chart review looking at levels of hearing preservation after cochlear implantation in children and adults, using different electrode insertion techniques (N = 144 ears from 32 patients). Pre- and postoperative pure tone thresholds at 250, 500, and 1000 Hz frequencies were measured. Statistical analysis was performed using nonparametric method (Kruskal Wallis test). Results: One hundred and four (72%) procedures were performed using standard cochleostomy, 25 (17 %) procedures were performed using soft surgery, and 15 (11 %) procedures were performed using round window insertion. Postoperative hearing thresholds were used as the main outcome measure. In all groups, residual hearing was preserved in different degrees (total: 30 %, moderate: 27 %, marginal: 37 %, none: 6 %). Statistically significant differences were encountered between the 3 groups. Soft surgery technique and round window insertion had better hearing preservation results compared to standard cochleostomy (P < .008 and P < .009, respectively). No difference between round window and soft surgery techniques was encountered (P = .07). Conclusion: Although cochlear implants are a revolutionary technology, they carry the risk of destroying residual hearing. Our study demonstrates that the use of soft surgery or round window techniques warrants better residual hearing when compared to standard cochleostomy.