Evaluation of Semicircular Canal Functions by the Video Head Impulse Test (vHIT) in Individuals with Motion Sickness

Background: In the occurrence of motion sickness, the functioning of the vestibular system in harmony has an important role. Aim/Objective: To evaluate the effectiveness of the vestibular system in individuals with motion disease with the Video Head Impulse Test (vHIT) device, which evaluates the vestibulo-ocular reflex (VOR). Materials and Methods: Thirty individuals with motion sickness (21 females, 9 males) and 30 healthy individuals (11 females, 19 males) without any vestibular complaints were examined with the vHIT device. All participants were older than 18 years. Results: It was observed that VOR gain values of the individuals with motion disease were significantly lower than those of the healthy individuals. Asymmetry values of the individuals with motion disease in all semicircular canals were higher than those of the healthy individuals; however, this difference was statistically significant only in the anterior semicircular canal. Conclusion and Significance: The observation of low gain values in all semicircular canals in individuals with motion sickness suggested that individuals with motion sickness may experience dysfunction in the sensory organelles in the vestibular system. Studies with larger case series and audiological test batteries will help us better understand motion sickness. Keywords: Motion sickness; vestibular; vHIT DOI: 10.7176/JHMN/79-05 Publication date:August 31st 202

Normative values for semicircular canal function with the video head impulse test (vHIT) in healthy adolescents

Background: The vHIT device, which has a mechanism based on measuring the VOR gain, helps us to quickly evaluate six semicircular canals. Aims/Objectives: The aim of this study was to establish normative values for semicircular canal function with the video head impulse test (vHIT) battery in normal adolescents. Material and methods: 100 (50 females, 50 males) individuals aged 11–18 years, with a mean age of 14.99 years, were included in the study. Results: As a result of the vHIT evaluations performed with vHIT Otometrics ICS Impulse A/S Taastrup, Denmark, the mean lateral canal vestibulo-ocular reflex (VOR) gain value was 0.96, the mean anterior canal VOR gain value was 0.89, and the mean posterior canal VOR gain value was 0.87, all of which were within the normal value range. Conclusion and significance: While the VOR gain values and asymmetry values are within the normal value range and are similar to the literature, no statistically significant correlation was observed between these values and age. As a result, the vHIT battery is an easy, fast, and practical test method that can be used in adolescents

An evaluation of the test-retest reliability of the functional head impulse test in healthy young adults

AimTo determine the test and retest reliability of the functional head impulse test (fHIT) in healthy young adults.Materials and methodsThirty-three healthy participants (17 women, 16 men) aged 18-30 years were included in the study. Each participant underwent the fHIT twice, 1 week apart, by the same experienced clinician. Intraclass correlation coefficients (ICCs) were used to determine test-retest reliability.ResultsThere was no statistically significant difference between the results of total percentage of correct answer (CA%) of the fHIT obtained in session 1 and session 2 measurements in the lateral, anterior, and posterior semicircular canals (SCCs) (p > 0.05). ICC values for test-retest reliability were found to range from 0.619 to 0.665 for the three semicircular canals (SCCs).ConclusionThe test-retest reliability of the fHIT device was moderate. Attention, cognition, and fatigue may be the factors reducing reliability. In the diagnosis, follow-up, and rehabilitation processes of vestibular diseases in clinics, changes in the fHIT CA% can be used to assess vestibulo-ocular reflex (VOR) functionality

Evaluation of utricular and saccular function in BPPV patients: The role of VEMP in diagnosis

Aim: The pathological cause of Benign Paroxysmal Positional Vertigo (BPPV) is the degeneration of the otolith organs (utricle and sacculus). Vestibular Evoked Myogenic Potentials (VEMP) assess the functions of the otolith organs. The objective of this research was to evaluate the otolith organ functions of patients with unilateral idiopathic BPPV (canalolithiasis of the posterior and lateral semicircular canals) by cVEMP and oVEMP tests. Material and Methods: The study prospectively included 35 patients with BPPV (canalolithiasis of the posterior and lateral semicircular canals) and 30 healthy individuals. Bilateral cVEMP and oVEMP tests were administered to all participants. Participants were divided into three groups: control, BPPV-affected ear, and unaffected ear.Results: In our study, cVEMP and oVEMP abnormalities were statistically significantly different both between the affected and unaffected ear groups and between the affected ear and control groups. There were statistically significant differences in the cVEMP and oVEMP amplitude values both between the affected and unaffected ear groups and between the affected ear and control groups. Also, the asymmetry ratios of the cVEMP and oVEMP tests were statistically significantly different between the case group and the control group. The cVEMP and oVEMP wave latencies (p1, n1, p1-n1) were not statistically significantly different among the BPPV-affected ear, unaffected ear, and control groups. The results of measurements were not statistically significantly different between the posterior and lateral canal involvement subgroups of BPPV patients.Conclusion: Abnormal cVEMP and oVEMP test results, which are observed more frequently in patients with BPPV compared to the control group, indicate utricular and saccular degeneration. Higher oVEMP abnormality ratios compared to those of cVEMP in BPPV patients suggest that utricular dysfunction may be more common than saccular dysfunction