Central auditory protheses to treat neural deafness including the novel double shank auditory midbrain implant

Background:

Patients with neural deafness cannot benefit from cochlear implants. Central auditory prosthesis bypass the damaged auditory nerve and stimulate electrically surgically accessible structures of the auditory system. 2 devices are currently available, the auditory brainstem implant (ABI) and the auditory midbrain implant (AMI). The presentation will focus on indications, surgical concept, results and future developments.

Methods:

85 ABI and 7 AMI patients were included in this study, suffering either from Neurofibromatosis type 2 (n = 51), postmeningitic deafness (n = 7), auditory nerve aplasia (n = 24) or cochlear aplasia (n = 10) with 39 children. AMI was chosen in patients with non functioning ABI due to brainstem damage or electrode migration. Electrode placement was checked intraoperatively by EABR monitoring and navigation and postoperatively by CT scan. All patients had audioverbal training. Postoperative hearing was measured with age adjusted audiometric measures.

Results:

84 patients have auditory sensation and use the device on a daily basis. The majority of patients has enhancement in lipreading, 39 patients achieved different levels of open set speech understanding. Children show a wide range of results with CAP scores between 1 and 6, on average 4.. AMI patients had ordered pitch sensation and better speech recognition scores than ABI patients.

Conclusion:

Central auditory prostheses are an effective therapy for both adults and children with neural deafness. The results show a large variability across patients which can be attributed to the number of active electrode contacts, electrode placement in the IC or additional function damage to the auditory pathways.

Publication History

Publication Date:
18 April 2018 (online)