Plontke, Stefan K.

Objective To evaluate cochlear implant speech perception among patients with sporadic inner ear schwannoma who underwent ipsilateral implantation. Study Design Retrospective multi-institutional cohort study. Setting Eleven tertiary academic medical centers across Germany, Denmark, and the United States. Patients One hundred six patients with sporadic inner ear schwannoma who received an ipsilateral cochlear implant from 2011 to 2022. Interventions Ipsilateral cochlear implantation with observation, stereotactic radiosurgery, or microsurgery for tumor management. Main Outcome Measures Monosyllabic speech perception testing scores and rates of open-set speech perception. Results Among 106 patients studied, 101 (95%) achieved open-set speech perception with a median of 24 months (interquartile range [IQR] 12–42 mo) of audiometric follow-up. Median ipsilateral monosyllabic speech perception testing achieved was 72% (IQR 54–85%), and median ipsilateral AzBio in quiet was 75% (IQR 46–90%). Most (91 of 106 [86%]) underwent microsurgery for tumor control, with cochlear implantation performed simultaneously in 98% (89 of 91) of these patients. The ability to achieve gross total resection significantly differed by tumor complexity, with 97% of low-complexity tumors, 100% of intermediate complexity, and 0% of high-complexity tumors undergoing gross total resection (p < 0.001). However, among patients managed with microsurgery, there was not a statistically significant difference in post-cochlear implantation monosyllabic speech perception scores across complexity groupings, with median scores of 75 and 70% for patients with tumors of low or intermediate complexity and those with tumors of high complexity, respectively (p = 0.5). Eight of 102 patients (8%) assessed experienced deterioration in cochlear implant performance over time. Among the subset of 39 patients with available MRI to review, the region of surveillance interest could be visualized postoperatively on MRI in all cases. Conclusions Open-set speech perception is achieved in most patients with inner ear schwannoma undergoing ipsilateral cochlear implantation. Although cochlear implantation in high-complexity inner ear schwannomas is only possible with incomplete tumor resection, long-term open-set speech perception outcomes are similar to lower-complexity tumors.

Objective To compare cochlear implant (CI) speech perception outcomes in patients with sporadic vestibular schwannoma (VS) managed with observation, radiosurgery, or microsurgery. Study Design Retrospective review. Setting Eleven tertiary academic medical centers. Patients One hundred patients with sporadic VS who received an ipsilateral CI. Interventions Ipsilateral cochlear implantation. Main Outcome Measures Pure-tone thresholds, monosyllabic speech perception testing scores, and rates of open-set speech acquisition. Results Of the 100 patients studied, 54 underwent microsurgery, 26 underwent radiosurgery, 19 continued observation, and 1 underwent multimodal therapy. Among all patients, the median post-implantation pure-tone average was 31 dB (interquartile range [IQR] 25–39 dB) and the median monosyllabic speech perception score was 30% (IQR 0–60%) at a median of 12 months (IQR 5–25 months) post-implantation. Patients who were managed with microsurgery (median speech perception score 11%, IQR 0–52%) exhibited poorer implant outcomes overall compared with those managed with observation (median speech perception score 52%, IQR 40–72%) or radiosurgery (median speech perception score 30%, IQR 16–60%). Open-set speech perception was achieved in 61% of patients managed with microsurgery, 100% with observation, and 80% with radiosurgery. In a multivariable setting, those managed with observation (p = 0.02) or who underwent radiosurgery (p = 0.04) were significantly more likely to achieve open-set speech perception compared with patients who underwent microsurgery. Conclusions Cochlear implants offer benefit in selected patients with sporadic VS. Although achieved in over half of people after microsurgery, open-set speech perception is more reliably attained in patients who are treated with observation or radiosurgery compared with microsurgical resection. These data may inform patient counseling and VS tumor management in people who may benefit from implantation.

ABSTRACT Over the past two decades, there has been increasing interest in the diagnosis and management of schwannomas of the inner ear including hearing rehabilitation with cochlear implants. However, tumor nomenclature and classification within the literature have been variable and oftentimes cumbersome. The term “intralabyrinthine schwannoma” is in common use when describing these tumors but is a potential source of confusion given that people often use the term “labyrinth” or “labyrinthine” to refer to the vestibular component of the inner ear only (i.e., labyrinthectomy or the translabyrinthine approach). During the Ninth Quadrennial Conference on Vestibular Schwannoma and Other Cerebellopontine Angle Lesions in Bergen, Norway, in May 2023, a multidisciplinary group of conference participants met and discussed issues pertaining to current terminology and classifications to enhance clarity and to reflect recent advances in tumor management and hearing rehabilitation. Although a variety of terms have been previously used to describe inner ear schwannomas, consensus was achieved on the term “inner ear schwannoma (IES)” to describe eighth nerve schwannomas of the cochlea, vestibule, or semicircular canals. Subgroups under this term comprise intravestibular, intracochlear, or intravestibulocochlear inner ear schwannomas (low complexity tumors), inner ear schwannomas with transfundal extension into the internal auditory canal but without modiolar involvement (intermediate complexity tumors), and inner ear schwannomas with transfundal extension with modiolar involvement (high complexity tumors). The details of the recommendations for an updated and simplified tumor nomenclature centered around tumor control and hearing rehabilitation with cochlear implantation are presented.