头脉冲抑制试验

头脉冲抑制试验（suppression head impulse paradigm,SHIMP）是在头脉冲试验（head impulse paradigm, HIMP）或者视频头脉冲试验（video head impulse test,vHIT）基础上发展而来的一种新型检查技术。SHIMP和HIMP都是通过计算前庭眼动反射增益（vestibulo ocular reflex gain,VOR gain）及校正性扫视（corrective saccades）来评估半规管功能的检查方法。VOR增益在两种检查中测定方法相似,扫视却相互补充：在HIMP中,代偿性扫视显示了前庭功能的损失,而在SHIMP中,反代偿性扫视显示了前庭功能的保留。本文就SHIMP的检测方法、原理及研究进展等进行综述。     

突发性聋伴眩晕患者头脉冲抑制试验特征分析

目的 探讨头脉冲抑制试验在外周前庭疾病中的应用价值.方法 以2019年10月至2020年4月确诊的33例突发性聋伴眩晕患者为研究对象,进行视频头脉冲试验(video head impulse test,vHIT),获取患者患侧头脉冲试验(head impulse paradigm,HIMP)和头脉冲抑制试验(suppr...     

视频头脉冲试验研究现状

视频头脉冲试验（video head impulse test, vHIT）是在Halmagyi头脉冲床旁检查基础上发展而来的视频头脉冲前庭诱发性试验,近年来被认为是一种能够反映前庭眼动反射（vestibulo-ocular reflex, VOR）直接通路完整性的无创高频检测技术,它除了能客观的评价水平半规管功能,还可对垂直半规管定量测定。本文就其起源和发展、主要原理、检测方法和临床应用做一综述。     

不同头动速度对健康人群视频头脉冲前庭眼反射增益的影响

目的研究视频头脉冲试验中不同头动速度对前庭眼反射增益的影响。方法对50名健康受试者应用视频头脉冲试验仪进行测试,以不同头动速度(50°/s-100°/s、101°/s-150°/s、151°/s-200°/s、201°/s-250°/s、251°/s-300°/s)将前庭眼反射增益值分组,分析头动速度对增益的影响。结果水平半规管平均增益按不同头动速度组(50°/s-100°/s、101°/s-150°/s、151°/s-200°/s、201°/s-250°/s、251°/s-300°/s)分别为0.992±0.130、0.983±0.154、0.999±0.151、0.945±0.142、0.835±0.106,其中201°/s-250°/s组与101°/s-150°/s组(P<0.05,P=0.035)、151°/s-200°/s组(P<0.01,P=0.000)差异显著,251°/s-300°/s组和其他组别间差异均显著(P1<0.01,P1=0.000;P2<0.01,P2=0.000;P3<0.01,P3=0.000;P4<0.05,P4=0.010);前半规管平均增益按不同头动速度组分别为0.984±0.136、0.916±0.181、0.926±0.179、0.895±0.169、0.863±0.174,其中50°/s-100°/s组和101°/s-150°/s组(P<0.05,P=0.018)、201°/s-250°组(P<0.01,P=0.005)间VOR增益差异显著;后半规管平均增益按不同头动速度组(50°/s-100°/s、101°/s-150°/s、151°/s-200°/s、201°/s-250°/s、251°/s-300°/s)分别为0.997±0.158、0.846±0.156、0.793±0.130、0.815±0.112、0.830±0.046,50°/s-100°/s组和101°/s-150°/s组(P<0.01,P=0.000)、151°/s-200°/s组(P<0.01,P=0.000)、201°/s-250°/s组(P<0.01,P=0.000)间差异显著,101°/s-150°/s组和151°/s-200°/s组间差异显著(P<0.01,P=0.001)。结论前庭眼反射增益随头动速度的提高呈现递减的趋势,其中部分组别存在显著差异,实际操作中应避免头动速度过低导致的结果误判。     

头脉冲试验评价单侧外周前庭病变患者的前庭眼动反射功能

目的 观察单侧外周前庭病变(unilateral peripheral vestibular disorder,uPVD)患者的头脉冲试验(head impulse test,HIT)和冷热试验,探讨HIT在眩晕患者前庭眼动反射功能评价中的临床价值.方法 135例uPVD患者均在同一天进行HIT与冷热试验检查.HIT左右两侧各测试3次.结果 判别方法为:在HIT检查中,以出现≥2次典型的回跳性眼震为阳性结果,出现≤1次典型的回跳性眼震为阴性;记录冷热试验中的半规管轻瘫(canal paresis,CP)值.并以冷热试验为前庭眼动反射功能检查的标准方法,分析HIT的灵敏度、特异度、阳性预测值及阴性预测值.结果 所有135例uPVD患者中,HIT出现3次阳性的有19例,出现2次阳性的为26例,HIT检查阳性率为33.3%,且所有阳性结果均发生在患侧;HIT检查出现1次和未出现回跳性眼震的共90例,阴性率为66.7%.HIT与冷热试验相比较,CP<30%时,HIT阳性6例,阴性58例;CP值为30%～99%,HIT 阳性24例,阴性28例;CP值为100%时,HIT阳性15例,阴性4例.以冷热试验为前庭眼动反射功能标准测试方法,则HIT的灵敏度为54.9%,特异度为90.6%,阳性预测值为86.7%,阴性预测值为64.4%.结论 对uPVD患者水平半规管前庭眼动反射功能进行评价,HIT与冷热试验相比较,其特异度高而灵敏度较低,提示HIT不能取代冷热试验的临床价值或作为其筛查试验方法,但HIT可作为冷热试验的补充,两种方法应结合应用.

Abstract：

Objective To evaluate the function of vestibular ocular reflex (VOR) in patients with unilateral peripheral vestibular disorder (uPVD) by the head impulse test (HIT). Methods The HIT and caloric test were carried out in 135 cases of patients with uPVD. The results of HIT were considered as normal (negative reaction) and abnormal (positive reaction). The results of vestibular function evaluated by caloric test were divided into three kinds, including normal, decreased and deficit according to the degree of canal paresis as less than 30 percent, from 30 to 99 percent, and equal to 100 percent, respectively. The sensitivity, specificity, positive and negative predictive value of HIT in assessing the vestibular function was analyzed. Results For the 135 patients with uPVD, the HIT was normal in 90 ( 66.7% ) cases and abnormal in 45 (33.3%) cases. When the caloric test was normal, the HIT was normal or abnormal in 58 cases and 6 cases, respectively. And when the canal paresis was from 30 to 99 percent, the HIT was normal or abnormal in 28 and 24 cases, respectively. When the vestibular function was deficit (CP was 100% ), the HIT was normal or abnormal in 4 cases and 15 cases, respectively. When the results of caloric test were considered as the standard method to evaluate the VOR, the sensitivity, specificity, positive and negative predictive value of HIT were 54.9%, 90.6%, 86.7%, and 64.4%, respectively. Conclusions When assessing the function of VOR in patients with uPVD, the HIT could not replace the caloric test, but it can be a supplementary method. The information from both the HIT and caloric test can be combined to evaluate the patients with vestibular hypofunction comprehensively.     

视抑制试验的临床应用研究

对２００例诊断明确的几种周边和中枢前庭疾病患者，在进行冷水试验的同时测试了视抑制功能，用眼震电图仪记录，计算ＶＳ值。１６２例周围性前庭损害者ＶＳ均正常，３８例中枢前庭损害者中２７例ＶＳ异常，占７１％。讨论了各种定量测试固视机能方法的优缺点，并就各种眩晕疾患的视抑制试验结果进行分析，探讨其临床意义。     

视频头脉冲试验的应用现状及研究进展北大核心CSCD

视频头脉冲试验(Video head impulse test,vHIT)是一种高频前庭功能检查技术,对于外周前庭疾病的判断起到重要作用。本文旨在探讨视频头脉冲试验的应用现状以及目前国内外的研究进展,希望帮助医师更好地运用vHIT进行眩晕疾病的辅助判断。     

Repeated video head impulse testing in patients is a stable measure of the passive vestibulo-ocular reflex

ObjectivesThe video head impulse test (vHIT) is used as a measure of compensation yet it’s stability in patients with vestibular pathology is unknown.Methods144 patients (n = 72 female, mean 54.46 ± 15.8 years) were grouped into one of three primary diagnoses (Peripheral, Central, or Mixed). Subjects were further categorized based on sex (male versus female), ear (left versus right; ipsilesional versus contralesional), age (six groups ranging from 19 to 84 years), and duration between visits (five groups, mean 191.46 ± SE 29.42 days, median 55.5 days). The gain of the VOR during passive head rotation was measured for each semicircular canal (horizontal, anterior, posterior).ResultsThere was no difference in the VOR gain within any semicircular canal between the two visits (horizontal: p = 0.179; anterior: p = 0.628; posterior: p = 0.613). However, the VOR gain from the horizontal canals was higher than the vertical canals for each visit (p < 0.001). Patients diagnosed with peripheral vestibular pathology had significantly lower (p ≤ 0.001) horizontal semicircular canal gains at each visit. There was no difference in VOR gain between sex (p = 0.215) or age groupings (p = 0.331). Test-retest reliability of vHIT in patient subjects is good (ICC = 0.801) and the VOR gain values across two separate visits were significant and positively correlated (r = 0.67) regardless of sex, ear, age, or duration between visits.ConclusionThe vHIT is a stable measure of VOR gain over two different times across a variety of vestibular patients with no influence of age or sex.     

Detection of isolated covert saccades with the video head impulse test in peripheral vestibular disorders

Objectives

The function of the semicircular canal receptors and the pathway of the vestibulo-ocular-reflex (VOR) can be diagnosed with the clinical head impulse test (cHIT). Recently, the video head impulse test (vHIT) has been introduced but so far there is little clinical experience with the vHIT in patients with peripheral vestibular disorders. The aim of the study was to investigate the horizontal VOR (hVOR) by means of vHIT in peripheral vestibular disorders.

Methods

Using the vHIT, we examined the hVOR in a group of 117 patients and a control group of 20 healthy subjects. The group of patients included vestibular neuritis (VN) (n = 52), vestibular schwannoma (VS) (n = 31), Ménière's disease (MD) (n = 22) and bilateral vestibulopathy (BV) (n = 12).

Results

Normal hVOR gain was at 0.96 ± 0.08, while abnormal hVOR gain was at 0.44 ± 0.20 (79.1% of all cases). An abnormal vHIT was found in VN (94.2%), VS (61.3%), MD (54.5%) and BV (91.7%). Three conditions of refixation saccades occurred frequently in cases with abnormal hVOR: isolated covert saccades (13.7%), isolated overt saccades (34.3%) and the combination of overt and covert saccades (52.0%).

Conclusions

The vHIT detects abnormal hVOR changes in the combination of gain assessment and refixation saccades. Since isolated covert saccades in hVOR changes can only be seen with vHIT, peripheral vestibular disorders are likely to be diagnosed incorrectly with the cHIT to a certain amount.     

Changes of video head impulse test results in lateral semicircular canal plane by different peak head velocities in patients with vestibular neuritis

Background: The peak head velocity influences on the video head impulse test (vHIT) results, but it has been not known how much the difference is.

Aims: To evaluate the clinical evidence for the superiority of high-velocity compared to low-velocity vHIT.

Material and methods: vHIT was performed in 30 patients with vestibular neuritis using two peak head velocities (mean 80 vs. 240°/s). vHIT gains and parameters of corrective saccades (CSs) were compared. A vHIT gain of ≤0.8 or a peak CS velocity of ≥100°/s was considered pathologic.

Results: The vHIT gains were significantly lower (mean 0.5 vs. 0.6), and GA was larger (35 vs. 25%) at high-velocity vHIT, compared to low-velocity vHIT. CSs were significantly more frequent (100 vs. 80%) and peak CS velocities were larger (252 vs. 112°/s) at high-velocity vHIT. The abnormal rates based on vHIT gains were higher (90% vs. 73%) and CSs occurred more frequently (100% vs. 80%) at high-velocity vHIT. The abnormal rates based on the peak CS velocity were significantly higher at high-velocity vHIT (100% vs. 57%).

Conclusion: High-velocity vHIT is superior to low-velocity vHIT with a difference of 17–20% based on pathologic vHIT gains and presence of CSs.     

HITCal: a software tool for analysis of video head impulse test responses

Conclusion: The developed software (HITCal) may be a useful tool in the analysis and measurement of the saccadic video head impulse test (vHIT) responses and with the experience obtained during its use the authors suggest that HITCal is an excellent method for enhanced exploration of vHIT outputs. Objective: To develop a (software) method to analyze and explore the vHIT responses, mainly saccades. Methods: HITCal was written using a computational development program; the function to access a vHIT file was programmed; extended head impulse exploration and measurement tools were created and an automated saccade analysis was developed using an experimental algorithm. For pre-release HITCal laboratory tests, a database of head impulse tests (HITs) was created with the data collected retrospectively in three reference centers. This HITs database was evaluated by humans and was also computed with HITCal. Results: The authors have successfully built HITCal and it has been released as open source software; the developed software was fully operative and all the proposed characteristics were incorporated in the released version. The automated saccades algorithm implemented in HITCal has good concordance with the assessment by human observers (Cohen’s kappa coefficient = 0.7).     

Effect of different head impulse procedures on vestibulo-ocular reflex gain

Objectiveto study the effects on vestibulo-ocular reflex (VOR) gain using both video head impulse test (vHIT) and Suppression Head impulse test (SHIMP) either using the outward or the inwards head impulse.MethodsTwenty healthy subjects were enrolled in the study. They were examined using otometric vHIT and SHIMP test lateral plane using the lateral outwards head impulse ten impulses for each side and the inwards head impulse ten impulses for each side. The VOR gain resulting from the outwards versus inwards head impulse during the vHIT and SHIMP were statistically compared.ResultsTwenty healthy subjects, 10 Males and 10 females with a mean age 35 ± 11.7. Paired t- test showed no statistical significance difference in the mean VOR gain of right lateral semicircular canal (1.1 ± .12) using outwards versus (1.03 ± .22) inwards head impulses, nor for the left lateral semicircular canal mean VOR gain (1.1 ± .22) using outwards head impulse (1.1 ± .3) for inwards head impulse in vHIT. Paired t- test showed no statistical significance difference in the mean VOR gain of right lateral semicircular canal (0.96 ± 0.2)using outwards versus (1.04 ± 0.2) inwards head impulses, nor for the left lateral semicircular canal mean VOR gain (0.98 ± 0.25) using outwards head impulse (1.1 ± 0.28) for inwards head impulse in SHIMP test. No statistical significant difference was found between the VOR gain resulting from the right versus the left semicircular canal.ConclusionThe starting head position does not affect the VOR gain using both vHIT and SHIMP tests.