Flat-based fitting: the evaluation and usefulness of a new strategy-based fitting approach for cochlear implants.

Abstract

The traditional fitting method for cochlear implants (CI), the single-channel fitting (SCF), is effective but time-consuming. A fitting method that is significantly faster to perform, but provides at least equivalent speech understanding and subjective benefit would be of clinical usefulness. The study explored the ability of flat strategy-based fitting (FSBF) maps to fill this need. Participants were 16 experienced CI users. They were fit with: SCF maps; the maps that the participants used in their everyday lives, called fine-tuned clinical (FTC) maps; and FSBF maps. The fittings were assessed objectively via speech understanding in noise, time needed to create the map, deviation from FTC map, and correlation between auditory response telemetry thresholds and normalized charge levels; and subjectively via spectral balance and hearing quality. FSBF maps were significantly faster to generate. FTC maps provided the best subjective hearing quality. In all other assessments, no significant differences were found. FSBF maps can save time and provide CI users with the same level of speech understanding in noise. Participants may have preferred the FTC maps that they were already acclimated to them. These results suggest that the FSBF method could be used in first-fittings or in challenging fitting situations, but subsequent fine-tuning is required in follow-up appointments to improve sound quality. The FSBF method can be a useful and time-saving alternative fitting method in first-fittings or in challenging fitting situations.