The role of cVEMPs and vHIT in the evaluation of otosclerosis and its eventual vestibular impairment: preliminary findings

The role of cVEMPs and vHIT in the evaluation of otosclerosis and its eventual vestibular impairment: preliminary findings. Objectives: Otosclerosis is one of the most common causes of hearing loss in adults, with a prevalence of 0.3% to 0.4% in Caucasians. Vestibular symptoms may occur, with an incidence ranging between 5% and 57% of patients. The aim of our study is to evaluate the vestibular function and its eventual changes after stapes surgery in patients affected by otosclerosis. Methods: Prospective case-control study. Twenty patients (17 females; age range 33–58; mean age 44) who underwent surgery for otosclerotic disease between April 2012 and February 2014 were prospectively studied. These patients underwent preoperative and postoperative audiological tests. Furthermore, vestibular function was evaluated using the cervical evoked myogenic potentials test (cVEMPs) and video head impulse test (vHIT), preoperatively and postoperatively. A case-control study was also performed. Quantitative and statistical analysis of patients’ vestibular function was carried out both before and after stapes surgery. Results: The means of the vHIT gains in the case group were 1.03 on the right side and 1.01 on the left side. A significant difference between case and control groups was seen, with a lower left gain registered in the control group. No cases with a gain of less than 0.8 were found in either group. Moreover, a significant postoperative reduction in P1/N1 amplitude was seen in patients complaining of postoperative dizziness or vertigo.Conclusions: These findings indicate a probable traumatic saccular impairment in patients with vestibular symptoms. However, a longer follow-up may help in understanding the behaviour of cVEMPs in post-stapes surgery vertigo.