Intraoperativ assessment of auditory nerve function using round-window eABR

Recording of electrically evoked auditory brainstem responses (eABR) provides a useful tool for the preoperative evaluation of auditory nerve function in challenging Cochlear Implant (CI) candidates. In addition, measures of electrically evoked responses can support the CI indication and evaluate the auditory function during the rehabilitation process. Especially in challenging clinical cases like malformations of the cochlea and/or auditory nerve, neurofibromatosis, acoustic neuroma surgery or auditory synaptopathy/neuropathy (AS/AN) a preoperative eeABR recording with transtympanic, electrical stimulation at the promontory, the round window niche or intracochlear in the basal turn can provide important indication criteria for CI-surgery or prognostic factors regarding the rehabilitation outcome after cochlear implantation. Compared with promontorial, electrical stimulation in the round window niche provides much more reliable and reproducible eABR (rw-eABR). The rw-eABR technique and results from different clinical cases will be presented. For electrical stimulation we used a free programmable neurostimulator "ISIS" (inomed company, Germany). In comparison to the mostly used promontory stimulation, round window stimulation leads to better and more reliable results.

Publication History

Article published online:
19 April 2024