Cochlear Implant Upper Stimulation Levels: eSRT vs. Loudness Scaling

Abstract

ObjectiveTo assess the difference in speech recognition and sound quality between programming upper stimulation levels using behavioral measures (loudness scaling) and electrically evoked stapedial reflex thresholds (eSRTs).Study DesignDouble-blinded acute comparison study.SettingCochlear implant (CI) program at a tertiary medical center.PatientsEighteen adult (mean age = 60 years) CI users and 20 ears.Main Outcome MeasuresSpeech recognition scores and sound quality ratings.ResultsMean word and sentence in noise recognition scores were 8 and 9 percentage points higher, respectively, for the eSRT-based map. The sound quality rating was 1.4 points higher for the eSRT-based map. Sixteen out of 20 participants preferred the eSRT-based map.ConclusionsStudy results show significantly higher speech recognition and more favorable sound quality using an eSRT-based map compared with a loudness-scaling map using a double-blinded testing approach. Additionally, results may be understated as 18 of 20 ears had eSRTs measured before study enrollment. Results underscore the importance of incorporating eSRTs into standard clinical practice to promote best outcomes for CI recipients.