The Value Electrical Stapedial Reflex Thresholds (eSRTs) Cochlear Implant Mapping

One of the most significant challenges in cochlear implant programming, particularly for very young children and those with an associated pathologies, is the measurement of subjective comfort levels (= C-Subjective). Currently, to define this C-Subjective level, patients are presented with a loudness scale and must indicate whether the sound stimulus, sent via the implant, is soft, comfortable, or loud. The lower and upper stimulation levels must be determined for each electrode in order to program the implant. For many patients this can be difficult due to a lack of auditory experience and confusion between the sensation of sound intensity (weak or loud) and frequency (low or high).

A less commonly used but more objective approach to programming upper stimulation levels involves the use of the electrical stapedial reflex threshold (eSRTs) value. eSRTs are a promising measure, given the demonstrated correlation between the threshold that generates a stapedial reflex and the C-subjective level. Furthermore, eSRTs can be recorded in the majority of patients, and can typically be evoked at a comfortable stimulation level i.e. inferior to the uncomfortable level.

The main objective of this study is investigate the link between subjective comfort levels (C-subjective levels) and the eSRT.