Figure 2: Vestibular evaluation before (a, b) and after (c, d) intratympanic application of gentamicin during vestibular prehabilitation before vestibular schwannoma surgery (case 2). a.) Caloric testing (x-axis: time [min], y-axis: slow phase velocity [°/sec]): right-sided hypofunction. b.) n10 amplitudes of ocular vestibular evoked myogenic potentials (oVEMPs) indicate symmetric utricular function before gentamicin treatment. c.) Loss of right-sided caloric excitability following three applications of intratympanic gentamicin. d.) The marked asymmetry of oVEMP n10 amplitudes indicates gentamicin-induced loss of utricular function on the right side.