Evaluating vertebrobasilar insufficiency and Meniere's disease: Insights from cervical vestibular evoked myogenic potential and video head impulse test.

Background and purpose:

This prospective study aimed to investigate diffe-rences in video head impulse test (vHIT) and cervical vestibular evoked myogenic poten-tial (cVEMP) findings between patients with vertebrobasilar insufficiency (VBI) and Meniere’s disease (MD) who experience episodic vertigo attacks.

A total of 27 patients with VBI and 37 patients with MD were enrolled into the study in a tertiary referral center. Inclusion criteria consisted of patients with a minimum of two previous vertigo attacks, unaccompanied by any neurological symptoms during an attack. All patients underwent horizontal canal h-vHIT and c-VEMP assessments following pure sound audiometric examinations. First, vHIT and cVEMP results for low and high flow sides in VBI patients were analyzed. Subsequently, data from the low-flow side in VBI patients and the affected side in MD patients were compared.

The mean vHIT values for low and high-flow volume sides in VBI patients were 0.68 and 0.88, respectively. In MD patients, mean vHIT values for affected and healthy sides were measured as 0.77 and 0.87, respectively. Abnormal results were observed in 66.7% of VBI patients and 51.4% of MD patients, with no statistically significant difference between the findings (p> 0.05). Upon examining the affected side, c-VEMP responses were absent in 41% of MD patients and 48% of VBI patients, with no statistically significant difference between the groups (p> 0.05).

vHIT and cVEMP assessments can be utilized as supplementary tools to radiologic investigations for the clinical diagnosis and follow-up of VBI. However, no significant differences were observed between vHIT and cVEMP findings in patients with MD and VBI.

Role of the video head impulse test in the evaluation of vestibulo-ocular reflex in individuals with Parkinson's disease.

Background and purpose:

Parkinson’s disease (PD) is the most common movement disorder and the second most common neu­rodegenerative disease of the central ner­vous system. Dizziness is frequently reported by PD patients, yet there is a paucity of research focusing on the vestibulo-ocular reflex (VOR) in this population using high-frequency vestibular testing. This study aims to investigate the VOR in individuals with PD using the video head thrust test with and without suppression. 

Forty individuals with PD and 40 healthy individuals were included in the study. According to the Hoehn-Yahr Scale, individuals with PD were defined as early stage with a score of 1–2.5 and middle to late stage with a score of 3 to 5. The Head Impulse Testing Paradigm (HIMP) and Suppression Head Impulse Testing Paradigm (SHIMP) were applied to all individuals.

No statistically significant difference was observed between the PD group and the control group in terms of semicircular canal (SCC) gains in both HIMP and SHIMP tests. No catch-up saccades were observed in the right anterior, right posterior, left anterior, and left posterior SCC planes in the PD and control groups. However, in the right lateral SCC plane 32 patients in the PD group had saccades, while 8 patients in the control group had saccades. In the left lateral SCC plane, 32 patients in the PD group and 9 patients in the control group had catch-up saccades. A statistically significant difference was observed in the number and amplitude of saccades in the right and left lateral SCC planes compared to the control group (p<0.05). In addition, in the PD group, the amplitude, peak velocity, and latency of the anticompensatory saccades seen in SHIMP showed a statistically significant difference compared to the control group (p<0.05).

VOR in the vertical SCC plane was not affected in individuals with PD. However, VOR in the lateral SCC plane was affected. It was concluded that when evaluating VOR with both HIMP and SHIMP in individuals with PD, the presence of catch-up saccades should be focused on and evaluated for possible vestibular dysfunction, even though SCC gains are normal. This study will contribute to a deeper understanding of vestibular function in PD, potentially informing better management strategies for dizziness in this population. 

Vestibular Dysfunction in Euthyroid Children with Hashimoto's Thyroiditis.

A relationship exists between autoimmune thyroid disorders and vestibular dysfunction. This study aimed to analyze cervicalevoked myogenic potentials (cVEMP) and video head impulse test (vHIT) results between children with Hashimoto thyroiditis (HT) and healthy controls to determine vestibular end-organ problems. Thirty-six children with HT and 30 healthy subjects were recruited. The main inclusion criteria for the healthy group were the presence of normal thyroid function and no clinical history of vestibular problems. Each participant (both HT and healthy groups) was assessed using audiovestibular tests, cVEMP, and vHIT. There was no significant difference between the groups in terms of cVEMP (p1 and n1) latencies for both ears. There was no significant difference in cVEMP amplitudes (p1-n1 peak-to-peak) between the groups. There were statistically significant differences in the VOR gain of the right and left ears between the groups (P < .001, P < .001). When we considered lower cutoff value as 0.80 for VOR gain, 29 of 36 patients with HT (80.6%) had lower VOR gain scores. Only 1 of 30 healthy participants (3.3%) had a lower VOR gain score. This difference was statistically significant (P < .001). Subclinical vestibulopathy may occur in children with HT. The vHIT seems to be a valuable tool for identifying and screening preclinical vestibular pathologies in this patient group.

[Evaluation of e-NIHSS scale combined with HINTS for posterior circulation ischemic stroke with vestibular symptoms].

Objective:To explore the predictive value of HINTS bedside examination and e-NIHSS scale for posterior circulation ischemia with vestibular symptoms. Methods:136 cases in total patients with acute vestibular syndrome（AVS） hospitalized in our hospital from April 2021 to April 2023 were selected as the study subjects, According to the classification of AVS etiology, patients with central AVS, namely posterior circulation ischemia（PCI）, were divided into case group（68 cases） and peripheral AVS patients were control group（68 cases）, Collect data and perform head impulse test-nystagmus-test of skew deviation test beside the bed, two doctors evaluated the NIHSS and e-NIHSS scales for PCI patients with vestibular symptoms respecb tively, and recorded the results after they were consistent, and improved the head MRI examination. Results:The positive rate of head pulse test in PCI patients with vestibular symptoms was 3 cases（4.41%）, and 60 cases（88.24%） with peripheral symptoms; The positive rate of nystagmus test in PCI group was 64 cases（94.12%） and peripheral 21 cases（30.88%）; The positive rate of eye deviation test in PCI group was 55 cases（80.88%） and peripheral 8 cases（11.76%）. Comparing the data with the consistency of the final diagnosis, the sensitivity was 97.0%, the specificity was 95.7%, and the accuracy was 0.963. It passed the Kappa consistency test Kappa=0.926（P<0.01）. The patients in PCI group were scored, in which the NIHSS score of brainstem group was 1.51±0.59, and the e-NIHSS score was 4.05±1.71（P<0.05）; The NIHSS score of cerebellar group was 1.42±0.62, and the e-NIHSS score was 3.86±1.59（P<0.05）; NIHSS score of thalamus group was 1.31±0.73, e-NIHSS score was 3.56±1.27 （P<0.05）; NIHSS score of non-focus group was 1.11±0.43, e-NIHSS score was 3.06±1.20 （P<0.01）. The difference between e-NIHSS score and NIHSS score in each group was statistically significant. Conclusion:HINTS examination is highly consistent with the final diagnosis of the gold standard. The e-NIHSS scoring scale has a higher detection rate than the NIHSS scoring scale for patients with posterior circulation ischemia mainly characterize〓by vestibular symptoms.

Evaluation of the Effects of Optokinetic Stimuli and Dual-Task Performance on Vestibulo-Ocular Reflex Function in Children With Attention Deficit and Hyperactivity Disorder.

OBJECTIVES: This study investigated the effects of optokinetic stimuli and dual-task performance on vestibulo-ocular reflex (VOR) function. The study primarily focused on understanding the effects of attention deficit and hyperactivity disorder (ADHD) and its subtypes. STUDY DESIGN: A case-control study. SETTING: Tertiary medical centre. METHODS: Thirty-eight children diagnosed with ADHD and 40 typically developing (TD) children aged 8-18 were included in the study. According to their diagnostic reports, children diagnosed with ADHD were also examined in three subtypes: predominantly inattentive (ADHD-PI), predominantly hyperactive-impulsive (ADHD-HI) and the combined type. Functional head impulse test (fHIT) was applied to all participants in three conditions-with no additional stimulus, optokinetic stimulation and dual-task. Correct responses (CR) were determined for each group, and the conditions were compared. For the dual-task test performance, children were given a counting task. RESULTS: The findings of the study are significant. The CR values obtained from the fHIT tests applied under three different conditions were lower in the ADHD group compared to the control group. CR values for all fHIT conditions and all semicircular canals were lower in the ADHD-PI subtype and higher in the ADHD-HI subtype compared to other subgroups. CONCLUSION: This study has significant practical implications underscoring its relevance. fHIT, when applied with different protocols, can provide valuable information about the vestibular and cognitive states of children with ADHD. These results are particularly significant as the diagnosis of ADHD often relies on subjective interpretations, and fHIT offers a more objective and reliable method of evaluation.

Evaluation of Semicircular Canal Function in Relapsing Polychondritis Patients With Dizziness and Sensorineural Hearing Loss Using Video Head Impulse Test.

OBJECTIVE: To evaluate semicircular canal function using video head impulse test (vHIT) in relapsing polychondritis (RP) patients presenting with dizziness and sensorineural hearing loss. STUDY DESIGN: Retrospective case review. SETTING: Tertiary referral center. PATIENTS: Three patients with RP underwent vHIT and hearing tests. INTERVENTION: Diagnostic. MAIN OUTCOME MEASURES: The gain in vestibulo-ocular reflex (VOR) and the presence of catch-up saccade were examined, and the correlation between semicircular canal dysfunction and hearing loss was investigated. RESULTS: Of the six ears, five exhibited semicircular canal dysfunction. Among these, one ear showed dysfunction in two semicircular canals, while the remaining four ears demonstrated dysfunction in all three semicircular canals. Sensorineural hearing loss, ranging from moderate to profound, was detected by pure-tone audiometry in all six ears. Furthermore, a significant correlation was observed between VOR gain in the horizontal semicircular canal (HSC) and hearing level. CONCLUSIONS: This study demonstrated semicircular canal dysfunction in RP patients presenting with dizziness and hearing loss using vHIT. Moreover, a significant correlation was found between HSC dysfunction and the severity of hearing loss. While inner ear involvement is a key clinical symptom included in the diagnostic criteria for RP, there have been few reports evaluating vestibular dysfunction, and this is the first report on the evaluation of several cases using vHIT. Accurate assessment of vestibular function by vHIT may facilitate early diagnosis and intervention in RP, potentially improving patient outcomes.

Hyperventilation-Induced Nystagmus in Acute Unilateral Vestibulopathy: A Correlation with Vestibulo-ocular Reflex Gain and Clinical Implication.

Hyperventilation-induced nystagmus test (HINT) is capable of generating a response in 77.2% of cases of acute unilateral vestibulopathy (AUVP); both nystagmus toward the affected side (excitatory pattern) and toward the healthy side (inhibitory pattern) have been described. The aim of the study is to investigate the clinical and prognostic role of the test by evaluating its correlation with vestibulo-ocular reflex (VOR) gain. We evaluated 33 AUVP patients by performing the HINT and video head impulse test (V-HIT) during the acute phase and then at 15 and 90 days after the onset of the symptoms. The correlation between the VOR gain of the affected side and test responses was evaluated first, phase by phase, and then considering the pattern shown during the first assessments. Patients with a negative HINT had a higher mean VOR gain than patients with a positive test at both 15 and 90 days. Patients who showed an inhibitory pattern at the first assessment had a continuous improvement in V-HIT performance, while patients with an initial excitatory response had a transient decrease in gain at the subsequent evaluation (P=.001). No difference between these 2 groups emerged at 90 days (P=.09). The finding of a negative HINT during the follow-up correlates with good V-HIT performance and could be an indicator of good recovery. The inhibitory pattern is associated with a subsequent improvement; and it would be indicative of compensation. but, despite this, the prognostic value of the test is limited.

Assessing the Vestibulo-ocular Reflex of Contralesional Sides According to Head Impulse Velocity Utilizing the Video Head Impulse Test in Patients with Vestibular Neuritis.

There is a lack of comparative studies examining changes in vestibulo-ocular reflex (VOR) gain with head velocity in the video head impulse test (vHIT) of patients with vestibular neuritis (VN). Thus, the purpose of present study was to identify the effect of head impulse velocity on the gain of the VOR during the vHIT in patients with VN. Head impulse velocities ranging from 100%-200°/s [158.08 ± 23.00°/s in the horizontal canal (HC), 124.88 ± 14.80°/s in the anterior canal (AC), and 122.92 ± 14.26°/s in the posterior canal (PC) were used during vHIT trials of 32 patients with VN. Differences in VOR gain on the ipsilesional and contralesional sides according to head velocity were analyzed. The mean VOR gains in ipsilesional side were decreased to 0.47 in the HC and 0.56 in the AC, leading to marked asymmetry compared to the contralesional side; PC gain was relatively preserved at 0.82 in the ipsilesional side. The mean head impulse velocity applied during vHIT trials in each semicircular canal plane did not differ bilaterally. On the contralesional side, VOR gain was negatively correlated with head impulse velocity (R2=0.25, P=.004 in HC; R2=0.17, P=.021 in AC; R2=0.24, P=.005 in PC), while VOR gain on the ipsilesional sides of the HC and AC was not. Head impulse velocity may have a differential impact on VOR gain, depending on the degree of deficit. Increasing head velocity in vHIT may be considered to identify subtle deficits on the contralesional side of patients with VN.

Changes of video head impulse test before and after translabyrinthectomy in patients with acoustic neuroma. / å¬ç¥žç»ç˜¤æ‚£è€ ç»è¿·è·¯åˆ‡é™¤æœ¯å‰åŽè§†é¢‘å¤´è„‰å†²è¯•éªŒçš„å˜åŒ–.

OBJECTIVES: Acoustic neuroma (AN) is a benign tumor that usually affects a patient's hearing and balance function. For the screening and diagnosis of AN, the traditional approach mainly relies on audiological examination and magnetic resonance imaging (MRI), often ignoring the importance of vestibular function assessment in the affected area. As an emerging method of vestibular function detection, video head impulse test (vHIT) has been widely used in clinic, but research on its use in AN diagnosis is relatively limited. This study aims to explore the value of vHIT in the diagnosis of AN, vestibular dysfunction assessment, and postoperative compensation establishment in unilateral AN patients undergoing unilateral AN resection through labyrinthine approach. METHODS: This retrospective study was conducted on 27 AN patients who underwent unilateral AN resection via labyrinthine approach from October 2020 to March 2022 in the Department of Otolaryngology-Head and Neck Surgery, the Second Xiangya Hospital, Central South University. vHIT was performed 1 week before surgery to assess vestibular function, pure tone audiometry (PTA) was used to assess hearing level, and ear MRI was used to assess tumor size. Follow-up vHIT was conducted at 1 week, 1 month, 6 months, and 1 year post-surgery. The correlation of vHIT with hearing and tumor size was analyzed. RESULTS: Preoperative vHIT showed that the posterior semicircular canal on the affected side was the most common semicircular canal with reduced vestibulo-ocular reflex (VOR) gain. There was a correlation between the VOR gain of vHIT on the affected side and the hearing level (r=-0.47, P<0.05) or tumor size (r=-0.54, P<0.01). The results of vHIT on the affected side showed that the hearing level and mean VOR gain of the anterior semicircular canal increased slightly with time, and the amplitude and saccade percentage of the dominant saccades of the 3 semicircular canals increased, while the latency time decreased, with the most obvious changes occurring 1 week post-surgery. CONCLUSIONS: vHIT can effectively monitor the changes of vestibular function in AN patients before and after surgery and has application value in assisting the diagnosis of vestibular dysfunction in AN patients.

Can Video Head Impulse Testing Be Used to Estimate the Involved Canal in Benign Paroxysmal Positional Vertigo?

BACKGROUND:  There may be confusion about which canal is involved in patients with benign paroxysmal positional vertigo (BPPV), especially with those that have subtle findings. The study aimed to determine if video head impulse testing may be used in such patients as a diagnostic tool. Symptom scoring and treatment efficiency in BPPV are essential parts of the process. Therefore, inventories like "Dizziness Handicap Inventory" may be useful in this regard. METHODS:  Patients with posterior and lateral canal BPPV were included. Video head impulse testing was performed prior to treatment and 1 week after treatment. Vestibuloocular reflex (VOR) gains were noted and compared to the opposite side. The presence of correction saccades was noted as well. Also, pretreatment and posttreatment Dizziness Handicap Inventory scores were compared. RESULTS:  Fifty-seven patients were diagnosed with posterior canal BPPV, and sixteen were with horizontal canal BPPV. In patients with posterior canal BPPV, there was no difference between the involved canal VOR gains and the other canals on the same side (P=.639). The involved horizontal canal did not differ from the opposite horizontal canal. Patients with lateral canal BPPV show more significant improvement after treatment compared to patients with posterior canal BPPV. CONCLUSION:  Video head impulse testing may not be used to estimate the involved canal in BPPV; however, it may be used to evaluate the efficiency of the treatment, especially in the lateral canal.

[Correlation between parameters of suppression head impulse paradigm and changesin DHI score in acute vestibular neuritis].

Objective:To explore the correlation between the parameters of suppression head impulse paradigm（SHIMP） and changes in dizziness handicap inventory（DHI） scores. Additionally, to evaluate the degree of vertigo and prognosis of patients with acute vestibular neuritis through SHIMP parameters. Methods:Thirty-three patients with acute vestibular neuritis were enrolled for DHI evaluation, vHIT and SHIMP. A secondary DHI score were evaluated after after two weeks, once patients no longer exhibited spontaneous nystagmus. The decrease in the second DHI score was used as the efficacy index（EI）. All patients were divided into significantly effective group, effective group and ineffective group based on EI. Differences of the VOR gain values of SHIMP and the anti-compensatory saccade were compared among the three groups. Results:There were 13 cases in the significant effective group, 11 cases in the effective group, and 9 cases in the ineffective group. ①The mean gain of the horizontal semicircular canal in the significant effective group, the effective group, and the ineffective group was（0.50±0.11）, （0.44±0.12）, and（0.34±0.08）, respectively. The difference between the significant effective group and the ineffective group was statistically significant（P<0.01）. The gain of horizontal semicircular canal was positively correlated with EI（r=0.538 5, P<0.01） 。②The occurrence rate of the anti-compensatory saccade in the significant effective group, the effective group, and the ineffective group was（51.23±19.59）, （33.64±17.68）, and（13.78±11.81）, respectively. Pairwise comparisons between each group showed statistical significance（P<0.05）. The occurrence rate of anti-compensatory saccade was positively correlated with EI（r=0.658 2, P<0.01）. Conclusion:The horizontal semicircular canal gain and the occurrence rate of the anti-compensatory saccade in SHIMP for patients with acute vestibular neuritis were closely correlated with decrease in DHI score.

Positional End-Point Nystagmus in Patients with Diagnosis of Acute Unilateral Vestibulopathy.

INTRODUCTION: Recently, end-point nystagmus, traditionally observed in an upright position, has been identified in the Dix-Hallpike position among healthy subjects, suggesting a physiological origin.However, its characteristics in individuals with vestibular hypofunction remain unexplored. OBJECTIVE: To elucidate the impact of vestibular hypofunction on the characteristics of positional end-point nystagmus. METHODS: Thirty-one patients diagnosed with acute unilateral vestibulopathy according to Bárány Society criteria were selected. A video head impulse test was conducted in all participants, followed by McClure and Dix-Hallpike maneuvers with and without gaze fixation, and with the initial position of the eye in the straight-ahead position or in the horizontal end-point position. Nystagmus direction, sense, latency, slow-phase velocity, and duration were recorded. The relationship between these characteristics and video head impulse test values was analyzed. RESULTS: Positional end-point nystagmus was observed in 92.6% of subjects with vestibular hypofunction, significantly more than in healthy individuals. Nystagmus direction varied depending on the performed positional test and on the vestibulo-ocular reflex gains. Gaze occlusion and the initial horizontal end-point position increased its frequency. CONCLUSION: Vestibular hypofunction influences the manifestation of positional end-point nystagmus. Recognizing this nystagmus can aid in resolving diagnostic uncertainties and preventing the misdiagnosis of benign paroxysmal positional vertigo in subjects with acute unilateral vestibulopathy.

Vestibular evaluation with video head impulse test in pediatric cochlear implant patients.

BACKGROUND: The cochlear implant (CI) is effective for rehabilitating patients with severe to profound sensorineural hearing loss. However, its placement and use have been associated with various complications, such as those affecting the vestibular system. The objective of this study was to compare vestibular function using the video head impulse test (vHIT) in pediatric patients before and after CI placement. METHODS: A descriptive and retrospective study was conducted. The outcomes of 11 pediatric patients of both sexes with a history of profound hearing loss were evaluated. The results of vestibular-ocular reflex (VOR) gain, saccades, asymmetry, Pérez Rey (PR) index, and VOR/saccade ratio for both ears obtained by the vHIT test before and after CI placement were compared. RESULTS: Of the 11 patients evaluated, the VOR gain showed that 81.8% had normal function, 18.2% had hypofunction, and no patients had hyperfunction before implantation. No statistically significant differences were found when compared with post-implant off and post-implant on conditions (p > 0.05). The extracted variables, asymmetry, PR index, and the VOR/saccades ratio also showed no statistically significant differences between the pre- and post-implant conditions, whether off or on. CONCLUSIONS: The vestibular function of pediatric patients did not show significant changes before and after CI placement. The vHIT test is a valuable tool for assessing vestibular function and could be considered a criterion for surgical and rehabilitation decisions in patients undergoing CI placement.

INTRODUCCIÓN: El implante coclear es un dispositivo eficaz para la rehabilitación de pacientes con hipoacusia neurosensorial severa a profunda. Sin embargo, su colocación y uso se ha asociado a diversas complicaciones, entre ellas a nivel del sistema vestibular. El objetivo del presente estudio fue comparar la función vestibular mediante la prueba de videoimpulso cefálico (vHIT) de pacientes pediátricos antes y después de la colocación del implante coclear. MÉTODOS: Se llevó a cabo un estudio descriptivo y retrospectivo. Se evaluaron los resultados de 11 pacientes pediátricos de ambos sexos con antecedente de hipoacusia profunda. Se compararon los resultados de ganancia del VOR, sacadas, asimetría, índice PR así como la relación VOR/sacadas para ambos oídos obtenidos mediante la prueba vHIT antes y después de la colocación del implante coclear. RESULTADOS: De los 11 pacientes evaluados, la ganancia del VOR mostró que el 81.8% tenía normofunción, 18.2% hipofunción y ningún paciente hiperfunción antes del implante. Al compararlo con la ganancia post implante apagado y post implante encendido no se encontraron diferencias estadísticamente significativas (p > 0.05). Las variables sacadas, asimetría, índice PR así como la relación VOR/sacadas tampoco mostraron diferencias estadísticamente significativas entre las condiciones pre y pos implante ya sea apagado o encendido. CONCLUSIONES: La función vestibular de pacientes pediátricos no mostró cambios significativos previo y posterior a la colocación del implante coclear. La prueba vHIT es una herramienta útil que permite evaluar la función vestibular y que podría considerarse como criterio para tomar decisiones quirúrgicas en pacientes que se encuentran en protocolo para implante coclear.

The Role of Asymmetry Values, Gain, and Pathological Saccades of the Video Head Impulse Test (vHIT) in Sudden Sensorineural Hearing Loss.

OBJECTIVE: The purpose of this study was to evaluate the value of asymmetry values, gain, and pathological saccades of the video head impulse test (vHIT) in sudden sensorineural hearing loss (SSNHL). STUDY DESIGN: Retrospective study. SETTING: Tertiary referral center. PATIENTS: A total of 226 individuals diagnosed with unilateral definite SSNHL were hospitalized. The assessment included a comprehensive evaluation of medical history, pure-tone test, acoustic impedance, positional test, video nystagmography (VNG), vHIT, vestibular evoked myogenic potentials (VEMPs) and magnetic resonance. INTERVENTIONS: vHIT, VNG, cVEMP, oVEMP. Statistical analysis was performed with SPSS version 22.0 for Windows. MAIN OUTCOME MEASURES: The asymmetry values, gain, and pathological saccades of the vHIT. RESULTS: The abnormal gain of vHIT in anterior, horizontal, and posterior canal in SSNHL patients with vertigo were revealed in 20 of 112 (17.9%), 24 of 112 (21.4%), and 60 of 112 (53.6%), respectively. The vHIT pathological saccades (overt + covert) of anterior, horizontal, and posterior canal in SSNHL patients with vertigo were observed in 5 of 112 (4.6%), 52 of 112 (46.4%), and 58 of 112 (51.8%), respectively. Multivariate analysis indicated that the prognosis of patients with vertigo was correlated with vHIT gain of posterior canal, pathological saccade in horizontal canal, asymmetric ratio of horizontal canal gain, asymmetric ratio of posterior canal gain, Canal paresis (%) on caloric test and spontaneous nystagmus. CONCLUSION: In the vHIT of patients with SSNHL with vertigo, the posterior canal is most easily affected. Reduced gain of posterior canal, pathological saccade of horizontal canal, and larger asymmetric gain of posterior canal and horizontal canal may be negative prognostic factors.

Neck rigidity: a pitfall for video head-impulse tests in Parkinson's disease.

Video head impulse tests (video-HITs) are commonly used for vestibular evaluation; however, the results can be contaminated by various artifacts, including technical errors, recording problems, and participant factors. Although video-HITs can be used in patients with Parkinson's disease (PD), the effect of neck rigidity has not been systematically investigated. This study aimed to investigate the effect of neck rigidity on video-HIT results in patients with PD. We prospectively recruited 140 consecutive patients with PD (mean age ± standard deviation = 68 ± 10 years, 69 men) between September 2021 and April 2024 at Korea University Medical Center. The video-HIT results were compared with those of 19 age- and sex-matched healthy participants. Neck rigidity was stratified as a subdomain of the Movement Disorder Society-Unified Parkinson's Disease Rating Scale motor part (MDS-UPDRS-III). In 59 patients, the vestibulo-ocular reflex (VOR) gain was overestimated in at least one canal plane (58/140, 41%), mostly in the anterior canal (AC, n = 44), followed by the horizontal (HC, n = 15) and posterior canals (PC, n = 7). VOR gain overestimation was also observed in patients with no (18/58, 35%), subtle (20/58, 34%), or mild (17/58, 29%) neck rigidity. Multivariable logistic regression analysis showed that VOR overestimation was positively associated with neck rigidity (odds ratio [OR] [95% confidence interval] = 1.51 [1.01-2.25], p = 0.043). The head velocities of patients decreased during head impulses for the AC (p = 0.033 for the right AC; p = 0.014 for the left AC), whereas eye velocities were similar to those of healthy participants. Our findings suggest that neck rigidity may be a confounder that can contaminate video-HIT results. Thus, the results of video-HITs, especially for the AC, should be interpreted with the context of head velocity during head impulses in patients with neck rigidity.

Computerized Rotational Head Impulse Test: Age-Dependent Normative Data.

PURPOSE: The objective of this study was to determine the normative vestibulo-ocular reflex gain output values of the computerized rotational head impulse test (crHIT) with stationary visual targets (earth bound) in healthy participants in each decade age band of life: 10-19, 20-29, 30-39, 40-49, 50-59, 60-69, and 70+ years. METHOD: Seventy-seven community-dwelling participants (10-85 years of age) with normal lateral semicircular canal (SCC) functioning and no symptoms or history of vestibular dysfunction were recruited through convenience sampling and assessed with the crHIT using stationary targets. These participants were assessed using two standard protocols in a randomized order. RESULTS: Results from 77 participants (M age = 46 years; 43 women, 34 men) were analyzed. Pearson's correlation coefficient and simple linear regression indicated a statistically significant relationship between crHIT gain output and age (p > .05) for right gain, 1030°/s2, and left gain, 1005°/s2. Although a statistically significant relationship was found, the slope was minor, demonstrating that the clinical effect of age on crHIT gain output was insignificant. Furthermore, no statistically significant relationship exists between crHIT gain output and gender (p > .05). Age-dependent normative data were calculated using the 2.5th and 97.5th confidence interval (CI) percentile method. The responses of angular vestibulo-ocular reflex (aVOR) gain values for crHIT are expected to occur within the range for lower limit reference interval (RI) of 0.85-0.9 and upper limit RI of 1.11-1.18 for 1030°/s2 and lower limit RI of 0.86-0.92 and upper limit RI of 1.13-1.16 for 1005°/s2. It can be expected that 90% CI of the population with normal lateral SCC functioning will have aVOR gain values that fall within this range. CONCLUSION: Despite a statistically significant relationship that exists with aVOR gain output and age, the changes are minor, declining by 0.0088 units per 10 years, justifying the same normative data for all decade age bands.

Evidence for the differential efficacy of yaw and pitch gaze stabilization mechanisms in people with multiple sclerosis.

People with multiple sclerosis (PwMS) who report dizziness often have gaze instability due to vestibulo-ocular reflex (VOR) deficiencies and compensatory saccade (CS) abnormalities. Herein, we aimed to describe and compare the gaze stabilization mechanisms for yaw and pitch head movements in PwMS. Thirty-seven PwMS (27 female, mean ± SD age = 53.4 ± 12.4 years old, median [IQR] Expanded Disability Status Scale Score = 3.5, [1.0]. We analyzed video head impulse test results for VOR gain, CS frequency, CS latency, gaze position error (GPE) at impulse end, and GPE at 400 ms after impulse start. Discrepancies were found for median [IQR] VOR gain in yaw (0.92 [0.14]) versus pitch-up (0.71 [0.44], p < 0.001) and pitch-down (0.81 [0.44], p = 0.014]), CS latency in yaw (258.13 [76.8]) ms versus pitch-up (208.78 [65.97]) ms, p = 0.001] and pitch-down (132.17 [97.56] ms, p = 0.006), GPE at impulse end in yaw (1.15 [1.85] degs versus pitch-up (2.71 [3.9] degs, p < 0.001), and GPE at 400 ms in yaw (-0.25 [0.98] degs) versus pitch-up (1.53 [1.07] degs, p < 0.001) and pitch-down (1.12 [1.82] degs, p = 0.001). Compared with yaw (0.91 [0.75]), CS frequency was similar for pitch-up (1.03 [0.93], p = 0.999) but lower for pitch-down (0.65 [0.64], p = 0.023). GPE at 400 ms was similar for yaw and pitch-down (1.88 [2.76] degs, p = 0.400). We postulate that MS may have preferentially damaged the vertical VOR and saccade pathways in this cohort.

Advances in the diagnosis and management of acute vertigo.

BACKGROUND: Patients presenting to the emergency department with acute vertigo pose a diagnostic challenge. While 'benign' peripheral vestibulopathy is the most common cause, the possibility of a posterior circulation stroke is paradoxically the most feared and missed diagnosis in the emergency department. OBJECTIVES: This review will attempt to cover the significant advances in the ability to diagnose acute vertigo that have occurred in the last two decades. The review discusses the role of neurological examinations, imaging and specific oculomotor examinations. The review then discusses the relative attributes of the Head Impulse-Nystagmus-Test of Skew plus hearing ('HINTS+') examination, the timing, triggers and targeted bedside eye examinations ('TiTrATE'), the associated symptoms, timing and triggers, examination signs and testing ('ATTEST') algorithm, and the spontaneous nystagmus, direction, head impulse testing and standing ('STANDING') algorithm. The most recent technological advancements in video-oculography guided care are discussed, as well as other potential advances for clinicians to look out for.

Use of the Head Impulse, Nystagmus, Test of Skew ('HINTS') assessment to aid differential diagnosis in acute vestibular syndrome in the hyperacute stroke setting.

BACKGROUND: Differential diagnosis of acute vertigo syndrome is challenging given the similarities between clinical presentations of posterior circulation stroke and peripheral vestibular dysfunction. The Head Impulse, Nystagmus, Test of Skew ('HINTS') assessment is a clinical bedside test used to aid diagnosis. METHODS: Comprehensive training on use of the Head Impulse, Nystagmus, Test of Skew assessment was provided to one stroke consultant, and the effectiveness of the test in that setting was assessed. Further education was completed with more members of the stroke and emergency department multi-disciplinary team. Quality improvement measures including magnetic resonance imaging use and bed utilisation were explored. RESULTS: Following training of one stroke consultant, the Head Impulse, Nystagmus, Test of Skew assessment was found to be a feasible, accurate bedside test within this acute stroke service. Further training for the multi-disciplinary team was completed, but outcome measures were not explored because of the coronavirus disease 2019 pandemic and maternity leave. CONCLUSION: There is a role for trained members of the multi-disciplinary team to successfully use the Head Impulse, Nystagmus, Test of Skew assessment in hyperacute stroke settings, to aid diagnosis in acute vertigo syndrome.

Video head impulse test in subacute and chronic stroke survivors: new perspectives for implementation of assessment in rehabilitation.

INTRODUCTION: The Video Head Impulse Test (vHIT) is a safe and reliable assessment of peripheral vestibular function. Many studies tested its accuracy in clinical settings for differential diagnosis and quantification of the vestibulo-oculomotor reflex (VOR) in various disorders. However, the results of its application after lesions of the CNS are discordant and have never been studied in rehabilitation. This study aims to assess the VOR performance in a sample of stroke survivors. METHODS: This is a cross-sectional study on 36 subacute and chronic stroke survivors; only persons with first-ever stroke and able to walk independently, even with supervision, were included. We performed VOR assessments for each semicircular canal by vHIT and balance assessments by the Berg Balance Scale and the MiniBESTest scale. RESULTS: Two hundred and sixteen semicircular canals were assessed using the Head Impulse paradigm (in both the vertical and horizontal planes), while 72 semicircular canals were assessed using the Suppressed Head Impulse paradigm (horizontal plane). There was a high prevalence of participants with dysfunctional canals, particularly for the left anterior and right posterior canals, which were each prevalent in more than one-third of our sample. Furthermore, 16 persons showed an isolated canal dysfunction. The mean VOR gain for the vertical canals had confidence intervals out of the normal values (0.74-0.91 right anterior; 0.74-0.82 right posterior; 0.73-0.87 left anterior). CONCLUSION: Our findings suggest that peripheral vestibular function may be impaired in people with stroke; a systematic assessment in a rehabilitation setting could allow a more personalized and patient-centred approach.