CC BY 4.0 · J Neurol Surg Rep 2019; 80(01): e1-e9
DOI: 10.1055/s-0038-1673649
Case Report
Georg Thieme Verlag KG Stuttgart · New York

Intraoperative Monitoring of the Cochlear Nerve during Neurofibromatosis Type-2 Vestibular Schwannoma Surgery and Description of a “Test Intracochlear Electrode”

Anand V. Kasbekar
1   Cambridge Skull Base Unit, Cambridge University Hospitals NHS Foundation Trust, Cambridge, United Kingdom
2   Department of Otorhinolaryngology, Head and Neck Surgery, Nottingham University Hospitals NHS Trust, Nottingham, United Kingdom
3   NIHR Nottingham Biomedical Research Centre, University of Nottingham, Nottingham, United Kingdom
,
Yu Chuen Tam
4   Emmeline Centre, Cambridge University Hospitals NHS Foundation Trust, Cambridge, United Kingdom
,
Robert P. Carlyon
5   Medical Research Council Cognition and Brain Sciences Unit, Cambridge, United Kingdom
,
John M. Deeks
5   Medical Research Council Cognition and Brain Sciences Unit, Cambridge, United Kingdom
,
Neil Donnelly
1   Cambridge Skull Base Unit, Cambridge University Hospitals NHS Foundation Trust, Cambridge, United Kingdom
,
James Tysome
1   Cambridge Skull Base Unit, Cambridge University Hospitals NHS Foundation Trust, Cambridge, United Kingdom
,
Richard Mannion
1   Cambridge Skull Base Unit, Cambridge University Hospitals NHS Foundation Trust, Cambridge, United Kingdom
,
Patrick R. Axon
1   Cambridge Skull Base Unit, Cambridge University Hospitals NHS Foundation Trust, Cambridge, United Kingdom
› Author Affiliations
Further Information

Publication History

26 November 2016

27 July 2017

Publication Date:
04 February 2019 (online)

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Abstract

Objectives A decision on whether to insert a cochlear implant can be made in neurofibromatosis 2 (NF2) if there is objective evidence of cochlear nerve (CN) function post vestibular schwannoma (VS) excision. We aimed to develop intraoperative CN monitoring to help in this decision.

Design We describe the intraoperative monitoring of a patient with NF2 and our stimulating and recording set up. A novel test electrode is used to stimulate the CN electrically.

Setting This study was set at a tertiary referral center for skull base pathology.

Main outcome measure Preserved auditory brainstem responses leading to cochlear implantation.

Results Electrical auditory brainstem response (EABR) waveforms will be displayed from different stages of the operation. A cochlear implant was inserted at the same sitting based on the EABR.

Conclusion Electrically evoked CN monitoring can provide objective evidence of CN function after VS excision and aid in the decision-making process of hearing rehabilitation in patients who will be rendered deaf.