Stapedius reflex measurements during surgery for cochlear implantation in children

Electrically evoked stapedius reflex measurements were obtained in 19 children during surgery for cochlear implantation. They all received the Nucleus device. Stapedius reflexes could be elicited in all the children with congenital deafness but not in all the children with an etiology of meningitis. The intraoperative stapedius reflex thresholds were compared with postoperative values obtained after fitting of the speech processor and with the children's long-term behavioral most comfortable levels (C-levels). The intraoperative reflex thresholds were considerably higher than the postoperative reflex thresholds (44 "stimulus level steps" on the average), which could in part be ascribed to the influence of anesthetics used during surgery. It was concluded that, especially in children with an etiology of meningitis, the intraoperative stapedius reflex threshold (even after corrections for the concentration of the volatile anesthetics used) was a weak predictor of the C-level.