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。     

视频头脉冲试验在眩晕疾病诊断中的应用研究

目的 探讨视频头脉冲试验（vHIT）评估周围性眩晕患者前庭眼反射（VOR）的临床价值。方法 选取2019年4月—2020年10月收治的52例良性阵发性位置性眩晕（BPPV）患者和57例前庭性神经炎（VN）患者为研究对象,并选取同期30名健康者作为对照。采用vHIT定量测定一对水平半规管平面、两对垂直半规管平面的VOR增益值及相应3个VOR增益不对称值,记录眼球追赶扫视信息,计算vHIT异常比率、增益值不对称比阳性率及代偿性扫视阳性率,并通过受试者工作特征曲线（ROC）分析vHIT诊断VN的敏感度和特异度。结果 与健康对照组和BPPV组比较,VN组患侧VOR增益值均减小,相应不对称值均增大。BPPV组与对照组增益值及增益不对称值比较,差异无统计学意义（P>0.05）;VN组vHIT异常比率、增益值不对称比阳性率及代偿性扫视阳性率均高于BPPV组;vHIT诊断VN的敏感度为85.96%,特异度为93.33%,阳性预测值为96.08%,阴性预测值为77.78%。结论 vHIT可通过VOR增益值、增益不对称值、vHIT异常比率、增益值不对称比阳性率及代偿性扫视阳性率对周围性眩晕患者的前庭功能进行评估,具有良好的临床应用价值。     

视频头脉冲试验在眩晕疾病诊治过程中的临床研究

目的探讨视频头脉冲试验(vHIT)评估中枢性眩晕和周围性眩晕的临床应用价值。方法选取2015年12月~2016年12月于我科就诊外周性眩晕者(外周组)38例、中枢性眩晕(中枢组)38例,及健康体检者40名作为对照组。采用vHIT检测获得各组3对半规管平面前庭眼反射(VOR)增益值和相应不对称值均值,计算vHIT异常比率、增益值不对称比阳性率及代偿性扫视阳性率。结果 (1)外周组患侧VOR增益值小于对照组和中枢组(均P0.01),而中枢组和对照组比较,差异无统计学意义(均P0.05);(2)外周组3个增益不对称值均高于对照组和中枢组(P=0.000)。中枢组水平增益不对称值与对照组比较,差异无统计学意义(P0.05),垂直增益不对称值低于对照组(均P0.05);(3)外周组vHIT异常比率、增益值不对称比阳性率及代偿性扫视阳性率均高于中枢组[36(94.74)vs 28(73.68);33(86.84)vs 13(34.21);29(76.32)vs 8(21.05);χ2=6.333、22.029、23.227,P=0.012、0.000、0.000]。结论vHIT通过VOR增益值、增益不对称值、vHIT异常比率、增益值不对称比阳性率及代偿性扫视阳性率评估眩晕患者的前庭功能,可以帮助鉴别诊断外周性眩晕和中枢性眩晕。     

骨导振动刺激诱发的前庭诱发肌源性电位

目的探讨B81骨振子在前庭诱发肌源性电位(vestibular evoked myogenic potentials, VEMPs)检测中的应用。方法对25例正常志愿者的双耳行插入式气导声刺激(air conducted sound, ACS),单侧乳突B81骨导振动刺激(bone conducted vibration, BCV)的VEMPs检查,并对ACS ,BCV VEMPs检查结果进行统计学分析。结果ACS ,BCV 眼肌前庭诱发肌源性电位(ocular vestibular evoked myogenic potentials, oVEMP)的引出率分别为92%（46/50）,98%（49/50）。BCV oVEMP与ACS oVEMP比较,两者引出率差异无统计学意义（P=0.36）;两者N1波潜伏期（P=0.00）、P1波潜伏期（P=0.00）、N1 P1波间期(P=0.01)及振幅(P=0.00)差异均具有统计学意义（P<0.05）;BCV oVEMP的N1、P1波潜伏期,N1 P1波间期均较短,而振幅较大。ACS ,BCV 颈肌前庭诱发肌源性电位(cervical vestibular evoked myogenic potential, cVEMP)的引出率均为100%（50/50）。BCV cVEMP与ACS cVEMP比较,N1波潜伏期差异无统计学意义（P=0.96）,P1波潜伏期（P=0.02）,P1 N1波间期(P=0.00)、振幅(P=0.04)均有统计学差异（P＜0.05）;BCV cVEMP的P1波潜伏期较短,P1 N1波间期较长,振幅较大。BCV oVEMP、ACS oVEMP、BCV cVEMP和ACS cVEMP的两耳间振幅不对称率（%）分别为：28.08±21.10、27.95±18.13、23.60±17.86、32.24±18.92。结论B81骨振子可以用于VEMPs的检测,骨导振动刺激在评价传导性听力损失患者的前庭耳石器功能时优于气导声刺激,可作为气导声刺激诱发VEMPs的补充检查。     

前庭自旋转试验检测结果分析

目的分析眩晕及平衡功能紊乱病人的前庭自动旋转试验（Vestibular Autorotation Test，VAT）检测结果，探讨VAT的临床应用价值。方法对65例眩晕及平衡功能障碍的患者在完成全面临床检查及耳神经功能检查的基础上行VAT测试。结果（1）单侧外周前庭功能损害10例，主要表现为水平前庭一眼反射（VOR）相位延迟及低增益，4例伴有非对称性异常，可伴有垂直VOR相位延迟及增益异常。（2）双侧外周前庭功能低下5例，非对称性均正常，主要表现为垂直VOR相位延迟及增益异常。（3）良性阵发性位置性眩晕（benign positional paroxysmal veaigo，BPPV）27例，其中有9例合并噪声性听力损失，主要异常表现为垂直VOR相位延迟和水平或垂直VOR高增益，部分可伴有水平VOR相位延迟。（4）可疑中枢性病变7例，多表现为水平VOR高增益和垂直VOR相位延迟。结论VAT能反应眩晕病人垂直VOR异常以及传统前庭功能检测不能显示的高频水平VOR异常，高频旋转试验是对前庭功能检测技术的发展和完善。     

前庭自旋转试验在前庭性偏头痛患者中的应用

目的探讨前庭自旋转试验（vestibular autorotation test, VAT）对前庭性偏头痛（vestibular migraine, VM）患者在前庭功能评估中的应用。方法对26例VM患者和20例正常人进行VAT检查，观察水平增益、水平相移、垂直增益、垂直相移、非对称性五项参数，≥1项异常，即评定为前庭功能异常，VAT试验阳性。结果VAT结果显示VM组21例（80.77%）前庭功能异常；对照组2例（10%）前庭功能异常，两组前庭功能异常检出率比较差异具有统计学意义（P<0.05）。VM患者增益异常18例（69.23%），其中水平增益增高12例次，垂直增益增高4例次,水平增益降低1例次，水平增益部分增高部分降低2例次。VM患者相移延迟16例（61.54%），其中水平相移延迟13例次，垂直相移延迟5例次。VM患者非对称性异常3例（11.54%），提示水平通路双侧前庭功能不对称，右侧功能较弱。VM患者增益异常以2.0~2.7 Hz为主，相移异常以3.5~5.9 Hz为主。结论VM患者以增益增高、相移延迟为主要特征，水平测试比垂直测试敏感。VAT对VM患者的前庭功能评估有效，其诊断能提供有价值的参考依据。     

前庭功能损失后普遍存在电动头脉冲试验中水平前庭眼反射的恢复

目的：对急性单侧外周前庭功能损失的患者使用电动头脉冲试验量化前庭功能的恢复,并把这些结果与其他体征和症状相比较。方法：使用电动头脉冲旋转仪记录30例突发单侧前庭功能障碍的患者平均在发生后3d（前期）的潜在的水平前庭眼反射（VOR）,20例患者平均3个月后（后期）继续测量。计算VOR增益和不对称（-x±s）。结果：从前期的患侧增益0．49±0．21到后期的0．79±0．23（P=O．0000）有高度显著改善。各自的不对称从（32±18）％到（12±14）％（P=0．0002）也有高度显著改善。至少80％的患者增益或不对称恢复。后期的高症状评分与低增益（P=0．043）和高不对称（P=0．018）有相关性。结论：用电动头脉冲旋转仪来测量减少的水平VOR增益,突发单侧前庭功能损失后至少部分恢复。除了眼震的传统评价,头脉冲试验的反应为前庭损失的严重程度和恢复提供了有价值的信息。     

突发性聋与前庭神经炎的前庭损伤差异性研究

目的　通过比较研究伴有前庭损伤的突发性聋和前庭神经炎,探讨两类疾病前庭损伤的差异。方法  2016-02-25～2016-07-20解放军总医院耳鼻咽喉头颈外科眩晕诊疗中心,突发性聋组55例,其中39例伴眩晕患者;前庭神经炎组46例。前庭双温冷热试验、头脉冲试验、颈性前庭诱发肌源性电位、眼性前庭诱发肌源性电位评价及比较突发性聋及前庭神经炎两组疾病前庭损伤差异性。结果　前庭双温冷热试验突发性聋组异常率25.45%,前庭神经炎组异常率97.82%,两组比较差异有统计学意义（χ2=54.01,P＜0.001）。头脉冲试验：突发性聋组异常率9.09%,前庭神经炎组异常率32.61%,两组比较差异有统计学意义（χ2=8.72,P =0.003）。颈性前庭诱发肌源性电位突 发性聋组异常率69.10%,前庭神经炎组异常率43.47%,两组比较差异有统计学意义（χ2=6.72,P =0.010）;眼性前庭诱发肌源性电位突发性聋组异常率54.55%,前庭神经炎组异常率63.04%,两组比较差异无统计学意义（χ2=0.745,P =0.388）。结论　突发性聋与前庭神经炎两组患者前庭损伤比较,突发性聋合并眩晕者更有可能为球囊/前庭下神经受累,损伤部位更多靠近神经终末端,损伤是低频段的;前庭神经炎的前庭损伤范围大,损伤是全频段的,高位可能性更大。     

后循环缺血性眩晕患者的前庭功能变化

目的　通过检测后循环缺血性眩晕（posterior circulation ischemic vertig, PCIV）患者前庭神经电生理和眼动功能的变化以探讨PCIV的前庭功能变化。 方法　对已经由临床和磁共振动脉成像或CT血管造影证实为PCIV的患者分别进行颈性前庭诱发肌源电位（cervical vestibular evoked myogenic potential, cVEMP）、眼性前庭诱发肌源电位（ocular vestibular evoked myogenic potential,oVEMP）、视频眼震电图（videonystagmography, VNG）及前庭双温交替试验（alternate bithermal caloric test, BT） 等检查,并将各项检测数据与对照组的相应数据进行统计学分析。结果　病例组cVEMP, oVEMP的潜伏期及左侧峰间振幅与对照组比较差异有统计学意义。病例组和对 照组cVEMP左右侧潜伏期差异分别为（t =11.4、9.55、 7.17和7.71, P＜0.00）。左侧峰间振幅差异（t =3.07, P＜0.00）。oVEMP左右侧潜伏期差异分别为（t =7.88、5.35、 7.58和6.39, P＜0.00）。左侧峰间振幅差异为（ t =2.33, P＜0.00）;右侧峰间振幅及双侧振幅差比值比较差异无统计学意义（P＞0.05）; VNG检查病例组扫视试验、平稳跟踪试验及视动试验的异常率明显增高,与对照组比较差异有显著性意义（扫视试验：χ2=7.35, P＜0.01;平稳跟踪试验及视动试验： χ2=8.08, P＜0.005）。病例组半规管轻瘫指数阳性率43%,对照组18%,两组半规管轻瘫指数对比差异有统计学意义（χ2=4.40, P＜0.05）。结论　VEMP主要检测前庭神经的电生理变化, VNG和BT注重于视眼动和视前庭功能检测,能够在神经体征和影像学变化出现前敏感检测出PCIV的前庭功能异常变化,对PCIV的诊断、治疗和预后判断具有较大的价值,值得临床推广应用。     

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。     

Video head impulse test (vHIT) in migraine dizziness

Background and objective

Migraine is an extremely prevalent primary headache disorder that frequently associates parallel symptoms such as dizziness, tinnitus and hearing loss. Our aim is to investigate differences in video head impulse (vHIT) results with patients suffering from vestibular migraine (VM) and healthy people, taking into consideration mean values of vestibule ocular reflex (VOR) gain, occurrence of the compensatory saccades latency and amplitude. According to the results, determine the usefulness of vHIT in vestibular migraine diagnostics.

Motorized head impulse rotator for horizontal vestibulo-ocular reflex: Normal responses

OBJECTIVE: To characterize the horizontal angular vestibulo-ocular reflex using a new motorized head impulse rotator and electro-oculography technique. DESIGN: Prospective case-control study. PARTICIPANTS: We included 22 healthy volunteers with unpredictable, horizontal motorized head impulses with a mean velocity of 170 degrees/s and a mean acceleration of 1550 degrees/s2. We recorded head and eye position and calculated gain, asymmetry, and latency of the vestibulo-ocular reflex. All subjects underwent testing twice while viewing a far (140 cm) target to evaluate the repeatability of the measurement. In addition, 8 of these subjects underwent testing while viewing a near (15 cm) target. We reported findings as mean +/- SD. RESULTS: The mean gain during the 30-millisecond interval before peak head velocity and during the interval when head velocity ranged from 100 degrees /s to 120 degrees/s was 1.08 +/- 0.10. The mean asymmetry in gain between sides was 3.7% +/- 2.8%, and the mean latency of the vestibulo-ocular reflex was 3.4 +/- 6.3 milliseconds. There was a statistically significant correlation between consecutive gain measurements for each subject (r = 0.59; P=.004). The mean gain for the near target was 1.26 +/- 0.10 and was significantly higher than that for the far target (P = .002). CONCLUSIONS: The vestibulo-ocular reflex measurements using our novel system are comparable to those achieved using other techniques. These results suggest that a motorized head impulse rotator with electro-oculography allows reliable and fast measurement of the vestibulo-ocular reflex. In addition, the method is safe, repeatable, and thus could be a useful tool in the clinical assessment of the vestibulo-ocular reflex.     

A clinical evaluation of head impulse testing

The head impulse test is a simple clinical test comprising high acceleration head rotation. In the presence of a severe unilateral vestibular weakness the normal vestibulo-ocular reflex is replaced by a misalignment of the eye followed by a series of corrective saccades which are evident to the examiner. Previous reports have shown the high sensitivity of the head impulse test in detecting complete unilateral weakness, but indicate poor sensitivity for mild weaknesses. This prospective, blinded study examined the head impulse test in a general clinical population of balance disorder patients to examine the sensitivity and specificity of the test, and to determine the degree of vestibular weakness that is required before the test becomes positive. One hundred and fifty patients were examined and the head impulse test results were compared to results from bithermal caloric testing. Results show that the overall sensitivity of the head impulse test is 34% with a specificity of 100%. The test does not detect mild or moderate vestibular weaknesses but is very sensitive to the presence of a severe paresis (87.5%). Head impulse testing will not replace caloric testing but is a very useful adjunct to it.     

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.     

Video head impulse test in bilateral vestibulopathy

IntroductionBilateral vestibulopathy is a rare chronic condition with multiple etiologies. Bilateral vestibulopathy is characterized mainly by unsteadiness when walking or standing, which worsens in darkness, as well as oscillopsia. The degree of handicap caused by bilateral vestibulopathy is variable and remains controversial.ObjectivesTo determine the value of the video Head Impulse Test in quantifying vestibular deficit and to establish its impact on the quality of life.MethodsTwenty patients (mean age, 41.9 years; range 14–80 years) fulfilling the recent Barany criteria of bilateral vestibulopathy, responded to the Situational Vertigo Questionnaire and underwent vestibular examination including fixation, positional tests, oculomotor test battery and video head impulse test.ResultsThe relation between each of the video head impulse test parameters and the scores from the questionnaire were statistically analyzed. We observed that patients with covert saccades on the video head impulse test were more likely to have a better quality of life than those with both covert and overt saccades, regardless of the vestibulo-ocular reflex gain in each semicircular canal. The presence of covert saccades was found to be associated with an improved quality of life regardless of the severity of vestibule ocular reflex-deficit. Our conclusion was that vestibule ocular reflex gain, measured by video head impulse test, does not quantify the severity of affection of quality of life in patients with bilateral vestibulopathy.ConclusionCovert saccades are strategies aiming at minimizing the blurring of vision during head movement, that is an adaptive mechanism that improves quality of life. Therefore, we recommend that video head impulse test should be a part of the routine diagnostic workup of bilateral vestibulopathy.     

Video head impulse test in vestibular migraine

IntroductionVestibular migraine as an entity was described in 1999 and its pathophysiology is still not established. Simultaneously with research to better understand vestibular migraine, there has been an improvement in vestibular function assessment. The video-head impulse test is one of the latest tools to evaluate vestibular function, measuring its vestibular-ocular reflex gain.ObjectiveTo evaluate vestibular function of vestibular migraine patients using video-head impulse test.MethodsCross-sectional case-control study homogeneous by age and gender with vestibular migraine patients according to the 2012–2013 Barany Society/International Headache Society diagnostic criteria submitted to video-head impulse test during intercrisis period.Results31 vestibular migraine patients were evaluated with a predominantly female group (90.3%) and mean age of 41 years old. Vestibular function was normal in both patient and control groups. Gain values for horizontal canals were similar between the two groups, but gain values for vertical canals were higher in the group with vestibular migraine (p < 0.05). Patients with vestibular migraine felt more dizziness while performing the video-head impulse test than control subjects (p < 0.001).ConclusionsPatients with vestibular migraine present normal vestibular function during intercrisis period when evaluated by video-head impulse test. Vertical canals, however, have higher gains in patients with vestibular migraine than in control subjects. Vestibular migraine patients feel dizziness more often while conducting video-head impulse test.     

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.     

Cervical vestibular evoked myogenic potentials and video head impulse test in Ménière disease

IntroductionMénière's disease is among the most frequent causes of vestibular disorders. Although it is a clinical diagnosis, a better understanding of the pathophysiology and clinical course of the disease through tests would allow improvement in the prognosis and more effective treatments.ObjectivesTo describe the results of the cervical vestibular evoked myogenic and video head impulse test in patients with a defined diagnosis of Ménière's disease and to correlate them with disease duration.MethodsThe sample consisted of 50 participants, of whom 29 comprised the study group and 21 the control group. The individuals were submitted to a questionnaire, otoscopy, audiometry and vestibular function assessment through the cervical vestibular evoked myogenic potential and video head impulse test.ResultsFor the video head impulse test, lateral canal gain values below 0.77 were considered abnormal and for the vertical channels, below 0.61. The percentages of normality were 82.76% for lateral, 89.65% for posterior and 91.37% for anterior canals. For the cervical vestibular evoked myogenic potential, the upper limits of normal for latencies were defined as 18.07 ms for p13 and 28.47 ms for n23; and in the SG, 19.57% showed prolongation of latency of p13 and 4.35% of wave n23, whereas 18.96% did not show biphasic potential.ConclusionsFor the video head impulse test, a decreased gain of the vestibulo-ocular reflex for the lateral canal was observed, with a higher incidence of overt type corrective saccades compared to the control group. For the cervical vestibular evoked myogenic potential, there was a significant difference between the groups for the inter-amplitude parameter, including for asymptomatic ears. There was no correlation between the results of the tests and disease duration.     

Evaluation of the vestibulo-ocular reflex in patients with chronic otitis media

IntroductionIn recent years, scientific evidence has shown that chronic otitis media may cause balance and vestibular dysfunction.ObjectiveTo compare the results of the video head impulse test (gain and symmetry of the vestibulo-ocular reflex and presence of covert and overt saccades) in patients with chronic otitis media and controls.MethodsCross-sectional study of patients with chronic otitis media (study group), aged between 18 and 60 years. The patients in the study group were further divided according to the chronic otitis media type as (1) non-suppurative, (2) suppurative, and (3) cholesteatomatous. For the comparative analysis, we selected volunteers with no history of ear and vestibular diseases (control group), who met the same inclusion and exclusion criteria as the study group. Patients in both groups underwent a video head impulse test.ResultsThe study group consisted of 96 volunteers, and the control group of 61 individuals. The prevalence of vestibular symptoms was 66% in the study group and 3.2% in the control group (p < 0.001). The results show a higher prevalence of changes in the vestibulo-ocular reflex gain (22.9%) and corrective saccades (12.6%) in the chronic otitis media group compared to the control group (p < 0.001). Despite the higher prevalence of changes in gain, the average vestibulo-ocular reflex gains in the chronic otitis media groups were within the pre-defined values ??of normality; however, the mean vestibulo-ocular reflex gain in the anterior semicircular canal was statistically worse in the cholesteatomatous chronic otitis media group compared to controls (p < 0.001). Regarding the corrective saccades, the prevalence of saccades was statistically higher in the suppurative and cholesteatomatous chronic otitis media subgroups compared to the non-suppurative and control groups (p = 0.004).ConclusionThe present study demonstrated that chronic otitis media is associated with a higher prevalence of vestibular symptoms and also a higher prevalence of changes in gain and corrective saccades when compared to controls.     

Clinical use of child-friendly video head impulse test in dizzy children

ObjectiveTo investigate the high-frequency vestibular functions using a child-friendly video head impulse test and to classify vestibular symptoms using a standard nomenclature guideline in dizzy children.Materials and methodsThe video head impulse test with a remote camera was used in this study. The data of 40 dizzy children (7.30 ± 4.75 years) were analyzed retrospectively.ResultsThe high-frequency vestibulo-ocular reflex gains of 14 (35%) dizzy children in the study group were reduced, whereas the vestibulo-ocular reflex gains of 26 (65%) dizzy children were normal. Two of them had a dramatic reduction in vestibulo-ocular reflex gains on their affected SCCs, but no corrective saccades as their gazes had not been fixated on the target at the onset of head impulses. In dizzy children, the most common cause was inner ear malformation (15%) and the most common vestibular symptom was unsteadiness (25%).ConclusionThe high-frequency vestibular function of the VOR in dizzy children, especially those suffering from IEM and unsteadiness, can be quickly screened using the vHIT device with the remote camera. However, clinicians should be careful during the interpretation of traces in the pediatric group.