Exploring Anatomy-Based Fitting for Cochlear Implantation: A Narrative Review

Importance Anatomy-based fitting (ABF) in cochlear implant (CI) users is an emerging method that individualizes the frequency allocation of the sound-coding strategies based on cochlear anatomy, aiming to reduce frequency-to-place mismatch and improve auditory outcomes. Objective To review current evidence on the rationale, processes, applications, and clinical significance of ABF, with a focus on its potential to improve speech perception, music appreciation, and overall sound quality. Design Narrative review of published literature on ABF in CI users, including English-language clinical studies identified through searches of PubMed, Scopus, and Web of Science using the terms “Anatomy-Based Fitting” and “Cochlear Implantation,” without restrictions on age or gender, while excluding non-English publications, animal studies, conference abstracts, letters, and commentaries. Intervention or Exposures Conceptual and technical approaches to individualizing CI frequency allocation using anatomical information obtained through medical imaging (eg, high-resolution computed tomography) to determine electrode array position relative to the modiolus and lateral wall, guiding optimal frequency allocation. Main Outcome Measures Different types of outcome measures were reported, including speech recognition, music and sound quality, psychoacoustic, electrophysiological, and patient-reported measures. Results Published studies suggest that aligning frequency mapping with individual cochlear anatomy can improve speech intelligibility, especially in challenging hearing settings, and enhance overall user satisfaction. Conclusions ABF is a promising method for CI fitting that accounts for anatomical variability to optimize frequency allocation, potentially improving auditory performance. Relevance Incorporating ABF into CI clinical practice may enhance individualization and improve hearing outcomes, representing a promising future direction in auditory rehabilitation.