Comparison of Cochlear Implant Efficacy in Pre- Versus Postsynaptic Auditory Neuropathy: A Systematic Review

Background: Etiological factors affecting outcomes of cochlear implants (Cis) are known; however, a direct comparison of efficacy based on lesion location is needed. We aimed to systematically examine the current evidence to compare the effectiveness of CIs in patients with presynaptic versus postsynaptic neuropathy. Methods: A comprehensive literature search was conducted across multiple databases, including MEDLINE (via PubMed), Embase, CENTRAL, Web of Science, Scopus, CINAHL, and PsycINFO. Studies were selected based on their examination of CI efficacy in patients with auditory neuropathy spectrum disorder, distinguishing between pre- and postsynaptic lesions using genetic markers or electrophysiological assessments. Results: Analysis of seven studies consistently highlighted the importance of etiological diagnosis in predicting CI outcomes. Genetic mutations were correlated with more favorable CI outcomes, emphasizing the role of genetic etiology. Electrophysiological measures also proved useful in assessing auditory function, further emphasizing the value of detailed diagnostics. Conclusion: Etiological factors generally influence CI outcomes; however, the success varies between pre- and postsynaptic neuropathies. Integrating genetic and electrophysiological diagnostics is crucial for predicting CI performance, suggesting a need for personalized approaches in evaluating CI candidates for more targeted and effective auditory rehabilitation.