Otolith-ocular responses in Meniere's patients before and after endolymphatic shunt operation

Caloric testing in prone/supine position and constant velocity off-vertical axis rotation (OVAR) in yaw axis (rotate-then-tilt paradigm) can evaluate labyrinth function and vestibular-ocular reflex (VOR) behaviour before and after endolymphatic shunt surgery (ESS). Preoperative and postoperative otolith dysfunction can be documented by constant velocity OVAR, before the VOR is modulated by the vestibular compensation. Vestibulo-ocular responses in prone/supine position and linear VOR (lVOR) OVAR responses were observed in 10 patients before and after ESS. Ipsilateral caloric reaction in prone/supine position was reduced after ESS. Otolith-ocular function and canal-otolith-interaction were improved postoperatively. Meniere's patients with bias component opposite to normal when rotating towards the lesioned ear showed relief of symptoms postoperatively. The bias component returning to normal can help to identify the relief of Meniere's attacks after ESS. The canal-otolith interaction can be observed pre- and postoperatively by means of caloric reaction in prone/supine position as part of the clinical routine.