Electrically Evoked Stapedial Reflex Threshold Levels: Relationship with Behavioural ‘T’ and ‘C’ Levels in Cochlear Implant Users

Abstract

Use of objective measures for programming cochlear implants in young children has become important due to their inability to provide reliable behavioural responses. The present study was carried out to determine the relationship between eSRT levels and threshold (‘T’) and comfort (‘C’) levels. A total of 11 participants in the age range of 5 to 16; 6 years were included. All participants used ‘Nucleus’ cochlear implants. The eSRT levels were measured from the electrodes 1, 7, 12, 17 and 22. These values were compared with the participants’ behaviourally set ‘T’ and ‘C’ levels. Paired t-test was used to compare the eSRT levels with the ‘C’ levels for the selected 5 electrodes. Spearman’s rank correlation was also used to investigate the relationship between the eSRT levels and behaviourally set ‘C’ and ‘T’ levels. The results revealed that the eSRT levels were higher than the ‘C’ levels in all the participants. Also, a significant difference between eSRT levels and ‘C’ levels was seen when the data of all the participants were analysed. However, no significant difference between eSRT levels and ‘C’ levels were obtained for the electrodes 1, 12, 17 and 22, when 6 participants with the difference of less than 30 current levels between eSRT levels and ‘C’ levels were analysed. Also, no significant correlation between the eSRT levels and ‘T’/’C’ levels were obtained. The eSRT levels obtained in the current study were found to overestimate the ‘C’ levels in most of the participants. However, these levels did not exceed the UCL of the participants.