Relationship between electrically evoked stapedius reflex threshold (ESRT) and stimulus burst duration in a group of children using cochlear implants.

Objectives: Objective measures mostly used to fit cochlear implants are the are the electrically evoked action potentials in the first place, followed by the electrically evoked stapedial reflex thresholds (ESRT). Several studies have shown that the general correlation between ESRT and subjectively measured comfort levels (MCL) is high (Hughes, 2012; Alvarez et al, 2007; Gordon, Papsin and Harrison, 2004; Lorens et al., 2004). ESRT variation due to stimulus duration needs to be investigate specially in the pediatric population regarding deviation according to stimulus length as well loudness. Material and methods: 26 children at the age less than 5 years, Med- El CI users, with all 12 active electrodes, with no cochlear malformation. Stimulation parameters as follow: burst duration: 100, 200, 300, 500 ms, stimulating electrodes: 2, 6, 9, 11. Results: For 13 children we managed to complete the procedure and to record ESR threshold for all mentioned durations, for seven children we receive no ESR response, for the rest -- we stopped the measurement. Conclusions: ESRT threshold values depend on such parameter as burst duration. Further measurements need to be done to find correlation between MCLs and objective threshold for different burst durati [ABSTRACT FROM AUTHOR]