Can and should vestibular schwannoma surgery be carried out via the endoscopic transcanal approach?
Reviewed by Aileen Lambert

The extent and scope of endoscopic ear surgery has rapidly progressed in recent years, and this paper, from one of the leading proponents of this technique, reports on the outcomes of a case series of patients who have had total excision of a vestibular schwannoma (VS) using an endoscopic-assisted transcanal retrocochlear approach to the IAC. The middle and apical turns of the cochlea are entirely preserved and the basal turn is partially preserved during the surgical dissection. The six consecutive patients in this study, collected in a three-month period, underwent surgery for VS tumours less than 20mm, without extension to the cerebellar-pontine angle, with serviceable hearing and normal facial nerve function. The paper uses detailed anatomic diagrams and endoscopic images to describe the approach used. In all cases reported in this series, the facial nerve was preserved and the tumour was completely excised. Post-excision EABR (electrically evoked auditory brainstem response) was used to document cochlear function outcomes – five out of the six patients tested had detectable intraoperative EABR after tumour removal. The authors state that this provides evidence of preserved auditory (and cochlear nerve) functionality and could allow cochlear implantation. They also explain that this study is part of a plan to develop this technique to allow not only preservation of hearing, but potentially restoration of hearing lost as part of the natural history of the VS progression. We await further results from this unit, and others, to see if this is a new direction for VS treatment in the future. It is worth mentioning that the patients in this cohort would, in the UK, be more likely to be offered stereotactic radiosurgery as first-line treatment for tumours of this size and location, rather than surgical excision.

Hearing Restoration During Vestibular Schwannoma Surgery With Transcanal Approach: Anatomical and Functional Preliminary Report.
Marchioni D, Veronese S, Carner M, et al.
OTOLOGY AND NEUROTOLOGY
2018;39(10):1304-10.