Preoperative Assessment of Cervical Vestibular Evoked Myogenic Potentials (cVEMPs) Help in Predicting Hearing Preservation After Removal of Vestibular Schwannomas Through a Middle Fossa Craniotomy

OBJECTIVE To determine whether cervical vestibular evoked myogenic potentials (cVEMPs) are predictive of hearing preservation in patients undergoing vestibular schwannoma removal through middle fossa craniotomy approach. STUDY DESIGN Retrospective case study. SETTING Tertiary referral center. PATIENTS Eighteen patients who underwent a middle fossa craniotomy for vestibular schwannoma (stage I or II of Koos classification) with attempted hearing preservation from January 2008 to February 2016 were retrospectively reviewed. INTERVENTION Pre-surgical cVEMPs test, videonystagmography (caloric test), and magnetic resonance imaging (MRI) as well as a pre- and post-surgical audiometry test. MAIN OUTCOME MEASURES cVEMPs parameters including amplitude asymmetry ratio (AR), P13, and N23 latencies and peak-to-peak amplitude between P13 and N23 waves were calculated. Hearing data were classified according to the AAO-HNS hearing classes. The nerve of origin of the tumor was specified during surgery and the largest tumor diameter was measure on MRI axial plane on T2-CISS weighed images. RESULTS Preoperative amplitude asymmetry ratio was lower (n = 15, Mann-Whitney U test, p