Evaluation of oVEMP and cVEMP in Superior Semicircular Canal Dehiscence Cases

Abstract

Superior semisircular canal dehiscence (SSCD) is a disease of the audiovestibular system, which occurs as a result of the lack of bone layer covering the superior semisircular canal. The disease forms a third window in the inner ear due to the lack of bone layer. The third window that occurs forms a pseudo conductive type of hearing loss, which has decreased bone thresholds in the audiometry test. Vestibular evoked myogenic potentials are an electrophysiological measurement method in which the responses of the neck or eye muscles to an acoustic stimulus are recorded by means of electrodes. The purpose of use is to evaluate the functions of the urticle and saccule, which are the vestibular end organs. Therefore its primary purpose is to diagnose semicircular canal dehiscence. This review is based on research from the last decade; diagnostic results of ocular vestibular evoked myogenic potentials (oVEMP) and cervical vestibular evoked myogenic potentials (cVEMP) tests were evaluated in cases of superior semicircular canal dehiscence (SSCD). Studies indicate abnormal decreases in cVEMP test thresholds on the affected side in SSCD cases. Additionally, a significant increase in oVEMP amplitude on the affected side has been reported. Results; It shows that evaluating these two tests together will contribute to the diagnosis of semicircular canal dehiscence cases.