Comparison of Objective Assessment of Oculomotor Function and Subjective Balance Test in Individuals with ANSD and Healthy Individuals

Abstract

Several studies have reported vestibular abnormalities, in addition to the established auditory dysfunction in individuals with ANSD. Despite their clinical relevance, objective analyses of behavioral balance assessments in conjunction with central oculomotor pathway function remain scarce in the literature. The aim of the present study was to compare the balance function scores of stabilometry and craniocorpography between individuals with and without ANSD. In addition, this study compared the central vestibular function using the VNG test between individuals with ANSD and healthy individuals. Thirty participants were included in the study of the age range of 18-55 years that were divided into two groups with the first group containing individuals diagnosed with ANSD and second group with fifteen healthy individuals. Saccade test, smooth pursuit test, optokinetic test and spontaneous nystagmus test were administered under VNG. To assess balance function scores, the Unterberger test, Romberg test and Tandem walking test of craniocorpography and, escalating sensory denial and escalating motor complexity of stabilometry were administered. Results revealed statistically significant differences between individuals diagnosed with ANSD and healthy individuals for average rightward gain of saccade test and average of gain of left to right optokinetic test in VNG. No significant difference was present in parameters of craniocorpography and stabilometry except for the vestibular sensory function scores. No correlation was present in the majority of parameters of VNG with the parameters of craniocorpography and stabilometry. The results from the VNG assessments align with existing evidence suggesting that auditory neuropathy spectrum disorder (ANSD) predominantly affects peripheral pathways, with minimal involvement of central oculomotor functions. Furthermore, the objective evaluation of behavioral balance performance highlights the role of central compensatory mechanisms and the intricate integration among multiple systems responsible for maintaining postural control, which may mitigate the functional consequences of vestibular impairment. The limited sample size of this study warrants the generalization of the findings of this study.