Abstract
Objective Ipsilateral cochlear implantation (CI) in vestibular schwannoma (VS) has been an
emerging trend over the last two decades. We conducted the first systematic review
of hearing outcomes comparing neurofibromatosis 2 (NF2) and sporadic VS undergoing
CI. A comparison of the two populations and predictor of outcome was assessed. This
is an update to a previously presented study.
Data Sources Systemic data searches were performed in PubMed NCBI and Scopus by an academic librarian.
No restrictions based on the year of publication were used.
Study Selection Studies were selected if patients had a diagnosis of NF2 and a CI placed in the affected
side with reports of hearing outcome. Two independent reviewers screened each abstract
and full-text article.
Data Extraction Studies were extracted at the patient level, and the assessment of quality and bias
was evaluated according to the National Institutes of Health Quality Assessment Tool.
Main Outcome Measures Outcome predictors were determined by using the chi-square test and Student's t-test.
Results Overall, most CI recipients functioned in the high-to-intermediate performer category
for both sporadic and NF2-related VS. Median AzBio (Arizona Biomedical Institute Sentence
Test) was 72% (interquartile range [IQR]: 50) in NF2 patients and 70% (IQR: 7.25)
in sporadic patients. Larger tumor size predicted a poorer final audiometric outcome.
Conclusions Categorization of hearing outcome into superior performance and inferior performance
based on sentence recognition revealed a generally good hearing outcome regardless
of treatment or patient population. Select patients with sporadic and NF2 VS may benefit
from CI.
Keywords
vestibular schwannoma - acoustic neuroma - neurofibromatosis type 2 - cochlear implant
- hearing conservation surgery - hearing rehabilitation - stereotactic radiosurgery
