Disease-Specific Patterns of Multidimensional Video Head Impulse Test Parameters in Peripheral Vestibular Disorders

Summary

This study characterizes the multidimensional vHIT features of MD, SSHL-V, and VN, and explores the potential relationship between compensatory saccades and early high-frequency vestibular dysfunction, with age showing no confounding effect.

Abstract

Video Head Impulse Test (vHIT) multidimensional parameters—namely vestibulo‑ocular reflex (VOR) gain, gain asymmetry (GA), and compensatory saccades (CS)—are core indicators for assessing peripheral vestibular dysfunction. The combined use of vHIT and caloric testing facilitates differential diagnosis of various vertigo syndromes. In this retrospective study, 310 adult patients with unilateral peripheral vestibular disorders were enrolled, comprising 170 cases of Ménière’s disease (MD), 110 cases of sudden sensorineural hearing loss accompanied by vertigo (SSHL‑V), and 30 cases of vestibular neuritis (VN). All participants underwent vHIT and a caloric test within 72 hours of symptom onset, prior to any therapeutic intervention. Analysis of vHIT metrics revealed distinct impairment patterns across the three disorders. Ménière’s disease was primarily characterized by CS abnormalities in the lateral semicircular canal (SCC), with a low gain reduction rate. Sudden sensorineural hearing loss with vertigo presents multi-planar impairment affecting both the lateral and posterior SCCs. Vestibular neuritis displayed concurrent abnormalities in VOR gain and compensatory saccades in the lateral SCC. In patients with normal VOR gain, unilateral weakness (UW) values were significantly elevated in CS‑positive groups for most semicircular canals. Age-stratified analysis revealed that age did not exert a discernible confounding effect on VOR gain or CS. This study systematically delineates the distinct vHIT parameter profiles of three common peripheral vestibular disorders, explores the possible relationship between compensatory saccades and early high-frequency vestibular dysfunction, and examines their relationship with caloric test outcomes.

Introduction

Vertigo is a common and complex clinical symptom, with approximately 60% of cases resulting from peripheral vestibular disorders¹. These disorders arise from pathological damage to the vestibular apparatus or vestibular nerve, leading to abnormal vestibulo-ocular reflex (VOR) function. Accurate assessment of vestibular function requires the combined use of the Video Head Impulse Test (vHIT) for evaluating high-frequency VOR function and the caloric test for evaluating low-frequency function.

Ménière's disease (MD), sudden sensorineural hearing loss with vertigo (SSHL-V), and vestibular neuritis (VN) are three common peripheral vestibular disorders with distinct underlying pathophysiologies. MD is primarily characterized by endolymphatic hydrops. It has been reported that patients with MD frequently exhibit normal vHIT gain values despite reduced responses on the caloric test². However, it remains unclear whether changes in semicircular canal diameter due to endolymphatic hydrops affect the occurrence of compensatory saccades (CS) in vHIT. SSHL-V is primarily caused by inner-ear microcirculatory disturbance or viral infection, involving both the cochlea and the vestibular apparatus; however, the pattern and extent of semicircular canal involvement remain controversial^3,4. VN results from selective inflammation of the vestibular nerve. Lee et al.⁵reported that 80.56% of VN patients had normal vHIT gain values, whereas Molnar et al.⁶observed synchronous abnormalities between vHIT and caloric test results. These pathophysiological differences may lead to distinct patterns of vHIT parameter abnormalities, yet systematic characterization of multidimensional vHIT profiles across these three disorders remains lacking.

The vHIT provides multiple parameters for evaluating semicircular canal function, including VOR gain (G), gain asymmetry (GA), and compensatory saccades (CS). VOR gain reflects the function of the direct vestibulo-ocular reflex arc, whereas CS represents a centrally mediated compensatory mechanism. However, most existing studies have relied on VOR gain as the sole evaluation metric, and patients with normal gain but abnormal saccades have often been excluded from the criteria used to determine abnormality. Furthermore, reports on the sensitivity and specificity of vHIT parameters vary considerably. A meta-analysis reported a sensitivity of 31%–36% and specificity of 83%–98%, while another study reported a sensitivity of 54%–90% and specificity of 46%–90%^7,8. This variability may be closely related to the lack of standardization in the selection of assessment parameters and interpretation criteria. Regarding the normal range of VOR gain, different studies have proposed varying thresholds^{9,10,11,12,13}. Nicolas et al. suggested >0.6, MacDougall et al. advocated >0.7, while Isaac and Alexander et al. proposed >0.8. These inconsistencies suggest that reliance on a single gain metric may be insufficient for a comprehensive assessment of vestibular function.

Therefore, the present study aimed to (1) explore the heterogeneous patterns of vHIT multidimensional parameters (G, GA, and CS) in three common peripheral vestibular disorders–MD, SSHL-V, and VN; (2) evaluate the relationship between CS status and caloric test results in patients with normal vHIT gain; and (3) assess the potential confounding effect of age on vHIT parameters. By systematically analyzing vHIT parameter patterns across these disorders, a reference framework was developed to interpret vHIT abnormalities in clinical practice and to identify the strengths of individual parameters in different diagnostic scenarios.

Protocol

The study was approved by the Ethics Review Board of Sun Yat-sen Memorial Hospital, Sun Yat-sen University (No. SYSKY-2025-572-01). Written informed consent was waived because of the retrospective nature of the study.

Patient selection
A total of 310 adult patients with unilateral peripheral vertigo were retrospectively enrolled between April 2020 and February 2025. The cohort comprised 137 males and 173 females, with a mean age of 51.05 ± 14.05 years. According to established international diagnostic criteria^14,15,16, 170 patients were diagnosed with Ménière's disease (MD), 110 with sudden sensorineural hearing loss accompanied by vertigo (SSHL-V), and 30 with vestibular neuritis (VN). The left ear was affected in 164 patients and the right ear in 146.

Eligible patients had complete medical history records and comprehensive clinical examination data and met the established diagnostic criteria for MD, SSHL-V, or VN. Patients were excluded if they had incomplete medical or examination records, an undetermined diagnosis of vertigo or central vertigo, or had received medications affecting central nervous system excitability or inhibitory function within 24 h before vestibular testing.

All patients underwent caloric testing and the video Head Impulse Test (vHIT) on the same day, within 72 h of symptom onset and before receiving any treatment. Before testing, all participants received standardized information regarding the purpose of the examinations and the required precautions.

Caloric test
Caloric testing was performed using an infrared video nystagmography system. Patients were placed in the supine position with the head elevated by 30° to align the lateral semicircular canals (SCCs) vertically. Before testing, the external auditory canals were examined using an electric otoscope. Following system calibration, a blind eye mask was applied, and each ear was sequentially irrigated with cold air (24 °C) and warm air (50 °C) in the following order: right cold (RC), left cold (LC), right warm (RW), and left warm (LW). Each irrigation lasted 60 s, during which nystagmus responses were recorded. An interval of 2–3 min was maintained between irrigations, and subsequent stimulation was initiated only after complete resolution of nystagmus and vertigo symptoms.

Slow-phase velocity (SPV) was measured during a 10-s interval corresponding to the peak caloric response. Unilateral weakness (UW) was calculated using the Jongkees formula, and a UW value ≥25% was considered abnormal¹⁷.

Video Head Impulse Test
The vHIT was performed using a video-oculography-based head impulse testing system with dedicated vestibular data acquisition and analysis software. Participants were seated approximately 1.5 m from a fixed visual target positioned at eye level while wearing lightweight goggles equipped with a high-speed video camera and head-motion sensor. Standard calibration was performed according to the manufacturer's instructions. The examiner stood behind each participant, stabilizing the head with one hand positioned near the posterior neck to minimize goggle displacement.

Rapid, unpredictable, low-amplitude head impulses (15°–20°) were delivered without prior warning in the plane of the target SCC. Testing included horizontal impulses for the right and left lateral SCCs (RL-LL plane) and vertical impulses for the right anterior-left posterior (RA-LP) and right posterior-left anterior (RP-LA) canal planes. Head impulses were delivered at velocities of 150–300°/s until at least 20 artifact-free responses had been obtained for each canal.

The evaluated vHIT parameters included vestibulo-ocular reflex (VOR) gain, gain asymmetry (GA), and pathological compensatory saccades (CS). Gain asymmetry was calculated using the formula GA = (R − L)/(R + L), where R and L represented the VOR gain values of the corresponding right and left SCC planes, respectively. Abnormal VOR gain was defined as <0.8 for the lateral SCCs and <0.7 for the vertical (anterior and posterior) SCCs. Pathological CS was defined as compensatory saccades occurring in more than 50% of head impulses, with a peak saccade velocity exceeding one-half of the corresponding peak head velocity and directed consistently with the VOR¹⁸. All vHIT recordings were acquired using the left-sided camera, irrespective of the affected ear. All examinations were performed by the same experienced technician, who remained blinded to the patients' clinical diagnoses throughout data acquisition.

Statistical analysis
Statistical analyses were performed using R software (version 4.2.1). To evaluate the potential confounding effect of age on vHIT parameters, patients were stratified according to the World Health Organization age classification into young (18–44 years, n = 100), middle-aged (45–64 years, n = 154), and elderly (≥65 years, n = 56) groups. Continuous variables with normal distribution were presented as mean ± standard deviation, while those with non-normal distribution were expressed as median with interquartile range (Q1, Q3). Categorical variables were reported as frequencies and percentages [n (%)]. The Kruskal-Wallis test was used to compare multiple groups with non-normally distributed data. Categorical variables were compared using the chi-square test or Fisher's exact test.

Within each disease group and inter-group comparison, the chi-square test and McNemar test were used to compare the frequencies of gain reduction and pathological CS among the three SCCs. The Mann–Whitney U test was used to compare UW median values between the CS-positive and CS-negative groups in patients with normal VOR gain. Receiver operating characteristic (ROC) curve analysis was performed separately within each disease group to evaluate the discriminatory performance of lateral SCC VOR gain and right lateral-left lateral SCC gain asymmetry (RL-LL GA) for caloric UW status. Optimal ROC cut-off values were determined using the maximum Youden index, and the areas under the ROC curves were compared using the DeLong test. 2 × 2 contingency tables were constructed to evaluate the diagnostic performance of pathological CS, and 95% confidence intervals for sensitivity, specificity, positive predictive value, and negative predictive value were calculated using the Clopper–Pearson exact method. All tests were two-sided, and P < 0.05 was considered statistically significant. Bonferroni correction was applied to adjust for multiple comparisons.

Results

Age-stratified analysis of vHIT parameters
The baseline characteristics of the three age groups are summarized in Table 1. Sex distribution was comparable among the groups (P = 0.906), whereas the distribution of disease types differed significantly (P = 0.0003), with a higher proportion of patients with Ménière's disease (MD) in the middle-aged group and a higher proportion of patients with vestibular neuritis (VN) in the young group.

Th...

Discussion

The present study enrolled 310 patients with peripheral vestibular disorders (Ménière's disease, sudden sensorineural hearing loss with vertigo, and vestibular neuritis) between April 2020 and February 2025, which partially overlaps with the recruitment period and patient cohort of a previously published 5-year retrospective study from the same research group (Zhang et al., Clin Otolaryngol, 2025; recruitment period: October 2018 to July 2024). The estimated overlap accounts for approximately 32.9% of the p...

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Video Head Impulse Test	Interacoustics	EyeSeeCam 1.1	The video head impulse test (vHIT) system, engineered for rapid and objective quantification of the vestibulo-ocular reflex (VOR), enables assessment of vestibular dysfunction in patients presenting with dizziness. Operating via real-time capture of head and eye movements through a high-speed camera, the system evaluates vestibular function, detects both covert and overt saccades, and supports vestibular function testing across all six semicircular canal planes. It is equipped with a lightweight anti-slip eye mask, ensuring both testing accuracy and patient comfort.
Video-nystagnography system	ZEHNIT Medical Technology	VertiGoggles-M system	Integrating a high-speed infrared binocular camera, the system enables high-precision 3D tracking of both ocular and head movements even under dark conditions, and supports real-time recording of horizontal, vertical, and torsional eye movements. It is indicated for the diagnostic evaluation of dizziness, vertigo, and balance disorders. Featuring plug-and-play USB connectivity, it is compatible with all standard caloric testing protocols.