Improved Outcomes in Auditory Brainstem Implantation with the Use of Near-Field Electrical Compound Action Potentials. (December 2014)

• Record Type: Journal Article
• Authors: Mandalà, Marco; Colletti, Liliana; Colletti, Giacomo; Colletti, Vittorio
• Is Part Of: Otolaryngology--head and neck surgery. Volume 151:Number 6(2014:Dec.)
• Page Start: 1008
• Page End: 1013
• Publication Date: 2014-12
• Subjects: auditory brainstem implant -- intraoperative monitoring -- electrical compound action potentials -- electrical auditory brainstem response; Head -- Surgery -- Periodicals; Neck -- Surgery -- Periodicals; Otolaryngology -- Periodicals; 617.51
• DOI: 10.1177/0194599814551151
• Languages: English
• ISSNs: 0194-5998

Abstract

Objective: To compare the outcomes (auditory threshold and open-set speech perception at 48-month follow-up) of a new near-field monitoring procedure, electrical compound action potential, on positioning the auditory brainstem implant electrode array on the surface of the cochlear nuclei versus the traditional far-field electrical auditory brainstem response. Study Design: Retrospective study. Setting: Tertiary referral center. Subjects and Methods: Among the 202 patients with auditory brainstem implants fitted and monitored with electrical auditory brainstem response during implant fitting, 9 also underwent electrical compound action potential recording. These subjects were matched retrospectively with a control group of 9 patients in whom only the electrical auditory brainstem response was recorded. Electrical compound action potentials were obtained using a cotton-wick recording electrode located near the surface of the cochlear nuclei and on several cranial nerves. Results: Significantly lower potential thresholds were observed with the recording electrode located on the cochlear nuclei surface compared with the electrical auditory brainstem response (104.4 ± 32.5 vs 158.9 ± 24.2, P = .0030). Electrical brainstem response and compound action potentials identified effects on the neighboring cranial nerves on 3.2 ± 2.4 and 7.8 ± 3.2 electrodes, respectively ( P = .0034). Open-set speech perception outcomes at 48-month follow-up had improved significantly in the near- versus far-field recording groups (78.9% versus 56.7%; P = .0051). Conclusions: Electrical compound action potentials during auditory brainstem implantation significantly improved the definition of the potential threshold and the number of auditory and extra-auditory waves generated. It led to the best coupling between the electrode array and cochlear nuclei, significantly improving the overall open-set speech perception.