Objective: To compare hearing preservation (HP) outcomes between lateral wall (LW) and perimodiolar (PM) cochlear implant electrode arrays. Databases reviewed: PubMed, Embase, Scopus, Web of Science, and ScienceDirect for studies published between January 2018 and April 2025. Methods: This review adhered to PRISMA guidelines. Studies were included if they reported HP outcomes stratified by electrode type (LW or PM) undergoing primary cochlear implantation (CI). The Joanna Briggs Institute (JBI) tools were used to assess risk of bias. Meta-analyses were conducted using random-effects models, and subgroup analyses were performed based on follow-up duration and HP criteria. Heterogeneity was assessed through the I ² statistic. Results: Of 976 screened records, 80 studies met inclusion criteria for synthesis, and 72 studies (n=3783 ears) were included in the meta-analysis. The overall pooled HP rate was 45.9% for LW electrodes and 34.2% for PM electrodes ( P <0.000005). In 18 head-to-head comparison studies (n=1710), the pooled risk ratio favored LW arrays (RR=1.24 0.99, 1.56, P =0.057). A sensitivity analysis excluding short-term studies (≤1 mo follow-up) revealed statistically significant superiority for LW arrays (RR=1.37 1.06, 1.77, P =0.016). Conclusions: LW electrode arrays were associated with higher overall HP rates compared with PM designs, although differences varied across follow-up durations and study types. Electrode selection should consider preoperative hearing status, cochlear anatomy, and surgeon experience to optimize outcomes.
Elisha et al. (Mon,) studied this question.