The Effects of Gusher-Related Intracochlear Pressure Changes on Hearing Preservation in Cochlear Implantation: A Comparative Series

Aim: To investigate and compare residual hearing preservation between patients based on the presence of intraoperative gusher. Methodology: We retrospectively compared 2 cohorts of cochlear implant recipients significantly distinguished by whether or not they experienced gusher intraoperatively. Patients underwent cochlear implantation using 24-mm lateral wall electrode arrays as well pharmacologic steroid protection. All patients were assessed by a hearing implant MDT. Hearing preservation rates and speech perception outcomes were assessed at 1, 6, 12, 24, 36, 48, and 60 months. Results: The patients with no gusher demonstrated complete hearing preservation. The patients with gusher demonstrated significant postoperative reduction of hearing thresholds, which declined at a significantly higher pace during follow-up. All patients demonstrated significantly better speech performance after cochlear implantation. Conclusion: The present study suggests that intraoperative gusher is associated with a significant drop in residual hearing, both immediately and over time, which may be related to the large change in intracochlear pressure intraoperatively.