INTRODUCTION:
Cochlear implants (CIs) are the one of the first examples of a neural prosthesis that can substitute a sensory organ to directly stimulate the auditory nerve. The core functions of a CI are to convert the input sounds into meaningful electrical stimulation patterns, and then to deliver these patterns to the auditory nerve fibers through a number of electrodes. The initial programming data include setting threshold levels (T-levels) and comfortable levels (C-levels). Accurate programming of these levels is required for a good map to access hearing and speech perception with the CI. Contraction of the stapedial muscle can be elicited by an adequate electrical stimulus. Electrically evoked stapedius reflex (ESR) has a threshold and demonstrates amplitude growth till saturation. Using Electrically evoked stapedius reflex threshold (ESRT)-based maps can be an objective method to program both adult and especially pediatric implantees, where behavioural responses are difficult to obtain. The goal of this study will be to compare ESRT-based mapping and behavioural-based mapping and whether if an ESRT-based mapping is a reliable and effective alternative for behavioural-based mapping when the latter cannot be obtained.