Caloric Test Research Articles

Dynamic change of vestibular function and the long-term prognosis of vestibular neuritis.

To comprehensively evaluate the dynamic change of vestibular function during long-term follow-up of vestibular neuritis, as well as the co-relationship with the outcomes of vestibular neuritis (VN), which provides the recommendations for vestibular function tests during the course of VN. A prospective cohort study was conducted on 16 patients with acute VN. Caloric test, vHIT, rotatory chair tests, VEMP, dizziness handicap inventory (DHI) score, and dynamic dizzy scales (VAS-DD) was first performed within 7 days of neuritis onset, which were further re-evaluated during the 6-12 months of follow-up. The dynamic changes on multiple objective vestibular examinations were analyzed during the acute and recovery stage of VN. We further evaluated the co-relationship between the vestibular dysfunction scales and the prognosis of VN. In more than 6 months of follow-up, 44% of the ultralow frequency, 94% of the low-to-mid frequency, and 44% of the high-frequency function of the horizontal semicircular canal returned to normal (p < 0.05). The change degree in symmetry of the rotatory chair test was correlated with the gain of the horizontal semicircular canal on the vHIT and the unilateral weakness (UW) value on the caloric test (p < 0.05). The change in DHI score was correlated with the phase; change in VAS-DD level correlated with the symmetry and TC of the rotatory chair test at VN recovery stage (p < 0.05). There was no significant correlation between the change in DHI score or change in VAS-DD and the degree of vestibular function recovery (p > 0.05). In general, vestibular function improved during the course of VN. The rotatory chair test can be used to evaluate the overall function of the vestibular system and the compensatory state in patients with VN.

Do measures of gain asymmetry and catch-up saccades improve video head impulse test agreement with caloric results?

ObjectiveTo investigate the relative sensitivity and agreement of caloric testing and video head impulse test (vHIT) across four groups of vestibular disorders. MethodsCaloric and vHIT results of 118 patients with either Ménière’s disease, vestibular neuritis/labyrinthitis, vestibular migraine, or vestibular schwannoma were retrospectively analyzed. vHIT gain, gain asymmetry, and catch-up-saccades (≥100°/sec) were compared with reference limits of 91 controls. ResultsAbnormal caloric results and vHIT gain were recorded in 57.6 % and 33.1 % of patients, respectively. Consideration of all three measures increased vHIT sensitivity to 43.2 %, and concordance with caloric results improved from 66.1 % to 70.3 %. A significant interaction effect confirmed the relationship between tests depended on the diagnosis (p = 0.013). Vestibular migraine and vestibular neuritis/labyrinthitis produced similar results on both tests, usually normal and abnormal respectively. Vestibular schwannoma produced more caloric abnormalities than vHIT gain but not compared with catch-up-saccades and gain asymmetry; Ménière’s disease produced more caloric abnormalities than all vHIT measures. When vHIT was normal (all measures), a 37 % canal paresis was 90 % specific for Ménière’s disease. ConclusionsRates of vHIT catch-up-saccades and gain asymmetry can improve sensitivity and concordance with caloric testing, but this is disease-dependent. SignificancevHIT outcome measures are complementary to the caloric test and each other.

Age-related differences in the characteristics of persistent postural-perceptual dizziness.

To investigate differences in the clinical characteristics of patients with persistent postural-perceptual dizziness (PPPD) according to age. We retrospectively reviewed 143 patients diagnosed with PPPD. Patients were classified into three groups by age: young group (19 to 44 years, n = 60), middle-age group (45 to 64 years, n = 56), old group (65 to 85 years, n = 27). Demographic data, scores of the Dizziness Handicap Inventory (DHI), the Niigata PPPD Questionnaire (NPQ), the Hospital Anxiety and Depression Scale (HADS), precipitating conditions, and the results of vestibular function tests including caloric testing, video head impulse test (vHIT), cervical and ocular vestibular evoked myogenic potentials (cVEMPs and oVEMPs), and posturography, were compared among the three groups. While there were no significant differences in the scores of the DHI or NPQ, the total score and anxiety score in HADS in the young group were significantly higher than in the old group (p < 0.05, each). On the other hand, for precipitating conditions, the rate of peripheral vestibular diseases was significantly greater in the old group (77.8%) compared to the young group (41.7%, p < 0.01). There was no significant difference in the results of caloric testing, vHIT, cVEMPs, or oVEMPs among the three groups. For posturography, the velocity of the center of pressure with eyes-open as well as with eyes-closed was significantly greater in the old group compared to the young group and the middle-age group (p < 0.005, respectively). The clinical characteristics of PPPD were different according to age. Young patients tended to have stronger anxiety than old patients whereas the old patients had a higher proportion of peripheral vestibular diseases among the precipitating conditions compared to young patients.

Triple semicircular canal occlusion with endolymphatic sac decompression for intractable Meniere's disease.

Meniere's disease (MD) is characterized by idiopathic endolymphatic hydrops (ELH). Frequent vertigo attacks is the most disabling symptom of MD. This study evaluated the efficacy of triple semicircular canal occlusion combined with endolymphatic sac decompression in the treatment of frequent vertigo in patients with MD. Eleven patients with complete medical records were included in this study conducted from May 2021 to April 2022. All patients were enrolled to undergo triple semicircular canal occlusion (TSCO) with endolymphatic sac decompression (ESD). Various tests including pure tone audiometry (PTA), vestibular evoked myogenic potentials (VEMPs), the video head impulse test (v-HIT), caloric test data, the Dizziness Handicap Inventory (DHI), the Berg Balance Scale (BBS), and the Tinnitus Handicap Inventory (THI) were performed both before and after the surgery. The successful control rate of vertigo was 100% (9/9) in the average 23-month postoperative follow-up period, with complete control rate of 88.89% (8/9) and substantial control rate of 11.11% (1/9). Triple semicircular canal occlusion combined with ESD may be an effective treatment option for managing frequent vertigo attacks in patients with MD. This combination therapy has the potential to become a significant addition to the treatment framework for MD.

The Caloric Test Is More Consistent With the Presence of Endolymphatic Hydrops Than the Vestibular-Evoked Myogenic Potential Test in Meniere's Disease.

Objective This study aimed to investigate the correlation between enhanced inner ear magnetic resonance imaging (MRI) findings and vestibular and cochlear function test results in patients with definite Meniere's disease and confirmed endolymphatic hydrops. Methods Among 70 consecutive patients diagnosed with definite Meniere's disease, 49 underwent contrast-enhanced 3-T inner ear MRI. The patients also underwent pure-tone audiometry, glycerol, caloric, and vestibular-evoked myogenic potential (VEMP) tests. Correlations between the pure-tone audiometry, glycerol test, caloric test, VEMP test, and MRI findings were evaluated using the chi-square test or Fisher's exact test, Student's t-test, one-way ANOVA, and Bonferroni's post-hoc test. Results Contrast-enhanced inner ear MRI revealed that 33 of 49 patients (67.3%) had endolymphatic hydrops. Among them, 19 patients had bilateral endolymphatic hydrops, and 14 had unilateral hydrops. The mean hearing threshold was higher in patients with endolymphatic hydrops than those without (p< 0.001). The proportion of patients with positive glycerol test results was higher among those with endolymphatic hydrops than in those without (p= 0.01). The rate of abnormal caloric response in patients with and without endolymphatic hydrops was not significantly different (p= 0.09). Furthermore, the rate of abnormal VEMP response in patients with and without endolymphatic hydrops was not significantly different (p= 0.70). On the affected side, in the caloric test, the ratio of the presence of vestibular and cochlear hydrops was similar (p= 1.00). On the affected side, in the VEMP test, the ratio of the presence of vestibular and cochlear hydrops was also similar (p= 0.80). The consistency of the caloric test in detecting cochlear hydrops was higher than that of the VEMP test (p= 0.04). The consistency of the caloric test in detecting vestibular hydrops tended to be higher (but not significantly) than that of the VEMP test (p= 0.11). Conclusion The cochlea and vestibule on the clinically affected side were more likely to have endolymphatic hydropsrevealed by contrast-enhanced 3-T inner ear MRI than on the unaffected side. The sum of the three low frequencies (125, 250, and 500 Hz) of the pure-tone audiometry was higher in patients with endolymphatic hydrops than in those without endolymphatic hydrops. The caloric test was more consistent in detecting endolymphatic hydrops, especially cochlear hydrops, than the VEMP test in patients with definite Meniere's disease. The results of this study may contribute to the future diagnosis of Meniere's disease and improve the understanding of endolymphatic hydrops.

Diagnosis dan Penatalaksanaan Penyakit Meniere

ABSTRACT&#x0D; Background: Meniere's disease is the third leading cause of vertigo after Benign Paroxysmal Positional Vertigo and vestibular neuritis. Meniere's disease is also known as endolymphatic hydrops. Acute symptoms of Meniere's disease are characterized by triad of vertigo, tinnitus and hearing loss. This disease is a challenge for ENT specialist in making a diagnosis and determining the right and optimal management. Objective: Provides knowledge about the diagnosis and management of Meniere's disease, so that it can be handled appropriately. Literature Review: Meniere's disease is an inner ear disorder characterized by spontaneous vertigo attacks, fluctuating low-tone sensorineural hearing loss, aural fullness and tinnitus. The most consistent finding and still being used as the basic mechanism of Meniere's disease to date is the discovery of endolymphatic hydrops. Diagnostic tests to diagnose Meniere's disease include audiometry, glycerol test, caloric test and electrocochleography. Meniere's disease can significantly affect quality of life and generally managed with dietary modifications such as a low-salt diet, medical therapy such as diuretics and surgery such as intratimpani injection and endolymphatic sac surgery. Conclusion: Meniere's disease is characterized by a triad of vertigo symptoms, low-tone sensorineural hearing loss and tinnitus. Making the diagnosis requires a detailed history with a complete audiology and vestibular examination. The management of Meniere's disease consists of dietary modifications, medical therapy and surgery.&#x0D; Keywords: meniere’s disease, endolymphatic hydrops, diuretics, intratimpani injection, endolymphatic sac surgery

A Case of Labyrinthitis Occuring in Undiagnosed Congenital Nystagmus

If direction-changing gaze-evoked nystagmus accompanies sudden hearing loss, central lesions should be considered as the cause. A 33-year-old female presented at our hospital with sudden hearing loss and dizziness. A series of vestibular function tests confirmed a visual fixation disorder with central causes; however, no specific findings were found on brain MRI. Subsequent smooth pursuit and optokinetic nystagmus tests confirmed bidirectional saccadic pursuit and reversed optokinetic nystagmus, suggesting congenital nystagmus. A history of abnormal eye tremors was rechecked, and labyrinthitis occurring in undiagnosed congenital nystagmus was diagnosed. The diagnosis can be challenging when vestibulocochlear disease occurs in patients with undiagnosed congenital nystagmus. In the absence of specific findings on MRI, vestibular function tests, including the optokinetic nystagmus and smooth pursuit tests, should be conducted. In particular, it is crucial to investigate the history of abnormal eye tremors.

Clinical diagnoses of patients showing caloric inversion

ObjectivesWhen air irrigation is used for caloric stimulation in patients with a perforated ear, warm irrigation may elicit a nystagmus that initially beats in the opposite direction of what is expected for warm irrigations, which is referred to as “caloric inversion”. This study aimed to investigate the disease group in which caloric inversion appeared in patients who underwent caloric testing and to classify the patterns of caloric inversion. MethodsWe conducted a retrospective review of bithermal caloric test results that were collected in our dizziness clinic between 2005 and 2022. Caloric inversion was defined when nystagmus induced by caloric stimulation appeared in the opposite direction to that expected. The incidence of caloric inversion among all patients who underwent bithermal caloric tests was calculated. To confirm the clinical diagnoses of the patients with caloric inversion, their clinical records were reviewed. ResultsOut of 9923 patients who underwent bithermal caloric tests, 29 patients (0.29%) showed a caloric inversion. The most common clinical diagnosis was chronic otitis media (21 of 29, 72%). Of the 21 patients with chronic otitis media, 20 patients showed a caloric inversion by warm air irrigation and one patient showed caloric inversion by cold air stimulation. Patients with clinical diagnoses other than chronic otitis media such as sudden sensorineural hearing loss, benign paroxysmal vertigo of childhood and recurrent vestibulopathy showed caloric inversion by warm air irrigation. Caloric inversion by warm water irrigation was observed in patients with lateral semicircular canal cupulopathy and recurrent vestibulopathy. Two patients (one with Meniere’s disease and one with age-related dizziness) showed caloric inversion by cold water irrigation. ConclusionCaloric inversion can be observed in various diseases other than chronic otitis media with tympanic membrane perforation. Special care should be taken in the interpretation of caloric test results. Level of EvidenceLevel 4.

The Need for Vestibular Implants in a Tertiary Referral Ear, Nose, and Throat Center and Its Relation to Hearing Status.

Patients with bilateral vestibulopathy (BVP) are at increased risk of falling and have poor quality of life. Several research groups are currently developing and investigating vestibular implants to treat BVP. The goal was to identify how many patients can be considered eligible for vestibular implantation. The objective vestibular implantation criteria for research were applied to the results of the caloric irrigation test, the sinusoidal harmonic acceleration test, the video head impulse test, and the cervical and ocular vestibular evoked myogenic potential tests. Vestibular implant eligibility was situated between 3.6% and 15.7% (semicircular canal implant: 3.6%; otolith implant: 15.7%; combined implant: 4.8%). Only 16 out of the 29 patients (55%) eligible for a vestibular implant had bilateral severe-to-profound hearing loss. The remaining 45% (13/29) thus have better hearing in at least 1 ear. Vestibular implant eligibility in an ear, nose, and throat department was situated between 3.6% and 15.7%, depending on the type of implant that was considered. In addition, the data showed that 45% of the eligible patients had normal-to-moderate hearing in at least 1 ear. In other words, only recruiting patients with (bilateral) severe-to-profound hearing loss for vestibular implantation leads to the systematic exclusion of about half of the candidates. Structure-preserving surgical techniques are thus a major future challenge in the field of vestibular implantation.

Evaluation of Mental Rotation Ability in Patients with Unilateral Benign Paroxysmal Positional Vertigo.

Our study aims to determine whether there are differences in mental rotation abilities between unilateral benign paroxysmal positional vertigo patients and healthy controls using object-based mental rotation tasks. Our study included 17 unilateral posterior canal benign paroxysmal positional vertigo patients and 20 healthy adults. Spontaneous nystagmus test, saccade test, and dynamic positional tests with videonystagmography and object-based mental rotation test with 2-dimensional images of cubes rotated at certain angles in 3-dimensional space were performed on the participants. The mental rotation test response time and the number of correct answers were compared between patients and controls. We also evaluated whether there was a relationship between saccade test parameters and mental rotation test parameters in our study. No significant relationship was found between benign paroxysmal positional vertigo patients and controls on any of the dependent measures (P -gt; .05). When we evaluated the relationship between saccadic latency and accuracy and mental rotation test response time and number of correct answers in benign paroxysmal positional vertigo patients, no significant relationship was found (P -gt; .05). Our findings show that unilateral, posterior canal benign paroxysmal positional vertigo does not affect object-based mental rotation performance. In our study, no correlation was found between saccadic function and mental rotation ability in unilateral benign paroxysmal positional vertigo patients.

Higher Cardio-Ankle Vascular Index Values in Patients With Vestibular Neuritis May Indicate a Better Prognosis.

The presumed etiology of vestibular neuritis (VN), a sudden onset of spontaneous vertigo without auditory or cranial nerve symptoms, includes viral infections and vascular disorders. However, no clinical test for estimating vascular disorders in VN has been reported. Moreover, estimating the etiology of VN is important to predict the prognosis and select appropriate treatment. This study aimed to evaluate the cardio-ankle vascular index (CAVI), which reflects arterial stiffness and elasticity, as an additional indicator for estimating the prognosis and etiology of VN. Among 207 consecutive patients with suspected VN, 88 patients diagnosed with definite VN were enrolled. Age, initial and final percent canal paresis (CP) in the caloric test, CAVI, presence or absence of vestibular-evoked myogenic potential asymmetry, and medical history were evaluated using univariate and multivariate analyses. Patients with VN with high CAVI had a better prognosis than those with low CAVI. High CAVI was a factor for improvement in percent CP, in addition to younger age and less severe initial percent CP in the Cox proportional hazard model. CAVI can be an additional indicator for estimating the prognosis and etiology of VN. This indicator can potentially be applied to other diseases, including vascular disorders with other etiologies.

Comparative study of vestibular function preservation in manual versus robotic-assisted cochlear implantation

Objective To compare vestibular outcomes in cochlear implant (CI) surgery, between robotic-assisted insertion of the electrodes versus manual insertion. Methods We performed a monocentric retrospective study. From March 2021, the robotic system RobOtol© was used for all CI cases. We compared this robotic-assisted insertion group with a manual insertion group of patients who received a CI between July 2020 and March 2021. Primary objective was vestibular outcome. We used objective vestibular function tests: caloric testing, Vestibular Evoked Myogenic Potential (VEMP), and Video Head Impulse Test (VHIT). Secondary objectives were postoperative complications including patient-reported postoperative vertigo. Results We found no statistically significant difference between the two groups in terms of caloric testing, VEMP or VHIT outcomes. In patient-reported outcomes, there was significantly more vertigo in the manual insertion group compared with robotic-assisted insertion. Conclusion It is hypothesized that a non-traumatic insertion would cause less vestibular dysfunction postoperatively. Larger prospective studies are required to determine whether robotic-assisted CI insertion has a significant impact on vestibular outcomes in CI surgery.

The Effects of Unilateral Labyrinthectomy on Monoamine Neurotransmitters in the Medial Vestibular Nucleus of Rats.

This study aimed to investigate the effects of unilateral labyrinthectomy (UL) on monoamine neurotransmitters in the medial vestibular nucleus (MVN) of rats. Adult Sprague-Dawley rats were utilized for the vestibular impaired animal model through UL. The success of the model establishment and the recovery process were evaluated using vestibular behavioral tests, including spontaneous nystagmus, postural asymmetry, and balance beam test. Additionally, the expression levels of c-Fos protein in the MVN were assessed by immunofluorescence. Furthermore, changes in the expression levels of monoamine neurotransmitters, including 5-hydroxytryptamine (5-HT), norepinephrine (NE), dopamine (DA), and histamine in the MVN, were analyzed using high-performance liquid chromatography (HPLC) at different time points after UL (4 h, 8 h, 1 day, 2 days, 4 days, and 7 days). Compared to the sham control group, the UL group exhibited the most pronounced vestibular impairment symptoms at 4 h post-UL, which significantly decreased at 4 days and almost fully recovered by 7 days. Immunofluorescence results showed a notable upregulation of c-Fos expression in the MVN subsequent to the UL-4 h, serving as a reliable indicator of heightened neuronal activity. In comparison with the sham group, HPLC analysis showed that the levels of 5-HT and NE in the ipsilesional MVN of the UL group were significantly elevated within 4 days after UL, and peaked on 1 day and 2 days, respectively. DA showed an increasing trend at different time points up to 7 days post-UL, while histamine levels significantly increased only at 1 day post-UL. UL-induced dynamic changes in monoamine neurotransmitters during the early compensation period in the rat MVN may be associated with the regulation of the central vestibular compensation mechanism by the MVN.

The acute vestibular syndrome: prevalence of new hearing loss and its diagnostic value

ObjectivesTo assess the prevalence of new hearing losses in patients with acute vestibular syndrome (AVS) and to start to evaluate its diagnostic value for the differentiation between peripheral and central causes.DesignWe performed a cross-sectional prospective study in AVS patients presenting to our Emergency Department (ED) from February 2015 to November 2020. All patients received an MRI, Head-impulse test, Nystagmus test and Test of skew (‘HINTS’), caloric testing and a pure-tone audiometry.ResultsWe assessed 71 AVS patients, 17 of whom had a central and 54 a peripheral cause of dizziness. 12.7% had an objective hearing loss. ‘HINTS’ had an accuracy of 78.9% to diagnose stroke, whereas ‘HINTS’ plus audiometry 73.2%. ‘HINTS’ sensitivity was 82.4% and specificity 77.8% compared to ‘HINTS’ plus audiometry showing a sensitivity of 82.4% and specificity of 70.4%. The four patients with stroke and minor stroke had all central ‘HINTS’. 55% of the patients did not perceive their new unilateral hearing loss.ConclusionsWe found that almost one-eighth of the AVS patients had a new onset of hearing loss and only half had self-reported it. ‘HINTS’ plus audiometry proved to be less accurate to diagnose a central cause than ‘HINTS’ alone. Audiometry offered little diagnostic accuracy to detect strokes in the ED but might be useful to objectify a new hearing loss that was underestimated in the acute phase. Complete hearing loss should be considered a red flag, as three in four patients suffered from a central cause.

Comparative utility of vestibular function tests in patients with peripheral and central vestibular dysfunction

BackgroundBithermal caloric irrigation, video head impulse test (vHIT), and rotational testing are commonly used to assess peripheral vestibular function, but the relative clinical utility of each test in differentiating patients with peripheral vestibulopathy is debated. ObjectivesTo determine whether (1) the combination of two or more vestibular tests enhances diagnostic utility over a single test; (2) abnormal test results on vestibular tests correlate with one another. MethodsRetrospective analysis of data collected from multidisciplinary vestibular clinics at two academic medical centers from 2016 to 2022. Results150 patients (54.10 ± 15.09 years, 88 females) were included. No individual test was significantly better at predicting the presence of peripheral vestibular damage (p > 0.05). vHIT test results improved significantly when combined with either the caloric test (p = 0.007) or rotary chair test (p = 0.039). Caloric and rotational testing had high sensitivity (74.65% and 76.06%, respectively) and specificity (83.54% and 78.48%, respectively). vHIT demonstrated excellent specificity (89.87%) but poor sensitivity (47.89%). Caloric, vHIT, and rotary chair tests results did not correlate with one another (p > 0.05). ConclusionsVestibular function tests have comparable diagnostic utility, yet each offers unique advantages. Caloric and rotational testing may be best suited for screening peripheral damage and vHIT may function ideally as a confirmatory test.

Vestibular function after simultaneous bilateral cochlear implantation in adults.

Binaural hearing enhances speech intelligibility, source localization, and speech comprehension in noisy environments. Although bilateral cochlear implantation (CI) offers several benefits, concerns arise regarding the risk of bilateral postoperative vestibular dysfunction with simultaneous CI. This study aimed to longitudinally evaluate changes in vestibular function in adult patients who underwent simultaneous bilateral CI using minimally invasive electrodes and surgical techniques. A retrospective review was conducted on 10 patients who underwent simultaneous bilateral CI at our hospital. Vertigo symptoms and vestibular function test results were examined preoperatively, 1-6 months postoperatively, and 1 year postoperatively. Nystagmus tests, caloric reflex tests, vestibular evoked myogenic potentials (VEMP) measurements, and static stabilometry were performed as vestibular function tests. Although an initial transient decline in vestibular function was observed, no significant long-term decline was observed in the caloric reflex test, ocular VEMP (oVEMP), or cervical VEMP (cVEMP). Moreover, regardless of the presence or absence of abnormalities in caloric reflex, oVEMP, or cVEMP, no significant deterioration was detected in the static stabilometer test. While two patients reported preoperative dizziness, all patients were symptom-free 1 year postoperatively. The findings suggest that using current minimally invasive electrodes and surgical techniques in simultaneous bilateral CI leads to temporary vestibular function decline postoperatively. However, most patients experience a recovery in function over time, highlighting the potential safety and efficacy of the procedure. Simultaneous bilateral CI surgery is viable, depending on the patient's auditory needs and burden.

Objective Neurological Testing Methods Used to Follow Up Vestibular Neuritis Depending on Different Factors.

We analyze the impact of different factors on clinical performance and prognosis in vestibular neuritis (VN) and explore indicators that could accurately reflect changes in patients' symptoms at different stages. We observed patients with VN during the acute and recovery phases. Clinical symptoms, vertigo-related scales, neurological examination, vestibular function tests (caloric test, video head impulse test (vHIT), vestibular evoked myogenic potential (VEMP)), and the history of disease (underlying diseases, glucocorticoid therapy) were recorded at onset and at 4 and 12 weeks after onset in VN patients. Multiple linear regression analysis was used to identify vestibular function tests that had a linear regression relationship with the subjective quantitative results. At 4 weeks after onset, the group without underlying disease had better improvement in EEV, gain, and UW than the group with underlying disease (P < 0.05). There was a significant difference in the change in DHI, EEV, gain of the affected horizontal semicircular canal in the vHIT and unilateral weakness (UW) between the glucocorticoid treatment group and the no glucocorticoid treatment group (P < 0.05), and glucocorticoid treatment group was better. The change value in the gain of horizontal canals in the vHIT was mainly positively and linearly correlated with the EEV scores (P<0.001). Possible dynamic correlation between vHIT results and vestibular symptoms. The absence of underlying disease and the receipt of glucocorticoid therapy significantly contributed to the improvement of objective vestibular function tests in the short term, while the improvement of subjective vertigo may correlate with the different objective measures and questionnaire. We believe that the improvement of the affected horizontal semicircular canal gain value in the vHIT can be used as a reference indicator of the degree of improvement of vestibular symptoms with superior vestibular neuritis.

Case series: Downbeat nystagmus in SCA27B

BackgroundSpinocerebellar ataxia (SCA) 27B, first reported in late 2022, is caused by the abnormal expansion of GAA repeats in the first intron of the FGF14 gene, which encodes the fibroblast growth factor 14. Case presentationWe present two late-onset cases, each manifesting mild cerebellar ataxia accompanied by omnidirectional downbeat nystagmus, which was enhanced in a suspended head position. None of the patients exhibited impaired head impulse or caloric tests. Repeat-primed PCR and targeted long-read nanopore sequence analysis of the FGF14 GAA repeat site identified more than 250 repeats, leading to the diagnosis of SCA27B. DiscussionDownbeat nystagmus is reported to be associated with disturbances in the suppression of the vestibulo-ocular reflex (VOR). Our patients with SCA27B demonstrated downbeat nystagmus, likely due to a disruption of the VOR at the level of the cerebellar cortex, a potentially characteristic clinical feature of SCA27B. We have included video footages of eye movements recorded using Frenzel goggles for these cases. ConclusionsOmnidirectional downbeat nystagmus may be a distinctive clinical feature of SCA27B.

Visual–vestibular sensory integration during congruent and incongruent self-rotation percepts using caloric vestibular stimulation

Introduction: The present study sets out to determine which sensory system mostly influences self-motion perception when visual and vestibular cues are in conflict. We paired caloric vestibular stimulation that signaled motion in either the clockwise or counter-clockwise direction with a visual display that indicated self-rotation in either the same or opposite directions.Methods: In Experiment 1 (E1), caloric vestibular stimulation was used to produce vestibular circular vection. In Experiment 2 (E2), a virtual optokinetic drum was used to produce visual circular vection in a VR headset. Vection speed, direction, and duration were recorded using a potentiometer knob the participant controlled in E1 and E2. In Experiment 3 (E3), visual and vestibular stimuli were matched to be at approximately equal speeds across visual and vestibular modalities for each participant setting up Experiment 4 (E4). In E4, participants observed a moving visual pattern in a virtual reality (VR) headset while receiving caloric vestibular stimulation. Participants rotated the potentiometer knob while attending to visual–vestibular stimuli presentations to indicate their perceived circular vection. E4 had two conditions: 1) A congruent condition where calorics and visual display indicated circular vection in the same direction; 2) an incongruent condition where calorics and visual display indicated circular vection in opposite directions.Results and discussion: There were equal reports of knob rotation in the direction consistent with the visual and vestibular self-rotation direction in the incongruent condition of E4 across trials. There were no significant differences in knob rotation speed and duration in both conditions. These results demonstrate that the brain appears to weigh visual and vestibular cues equally during a visual–vestibular conflict of approximately equal speeds. These results are most consistent with the optimal cue integration hypothesis.

Identification of vestibular loss in children with sensorineural hearing loss using the balance subset of the BOT-2 test

BackgroundVestibular loss in children with sensorineural hearing loss (SNHL) is quite high. Despite the high prevalence of vestibular loss and balance impairment in children with SNHL, they are rarely assessed by clinicians and therefore are commonly undiagnosed. The purpose of the study was to evaluate the balance subset of the Bruininks-Oseretsky Test (BOT-2) as a tool to identify vestibular loss in children with SNHL and to determine its predictive values for vestibular loss.MethodsThe study included 210 children allocated into 4 groups: group 1 (control healthy children), group II (children with SNHL but without vestibular loss), group III (children with SNHL and unilateral vestibular loss), and group IV (children with SNHL and bilateral vestibular loss). Caloric test, video head impulse test (vHIT), and cervical vestibular evoked myogenic potential (c-VEMP) test were used for vestibular assessment in children with SNHL and to allocate them accordingly into one of the aforementioned groups. Scores of the balance subset of the BOT-2 were compared among the three groups and compared to the control healthy children.Results21.4% of children with SNHL but without vestibular loss have balance deficit revealed by the balance subset of the BOT-2, reflecting its better sensitivity for detecting balance deficit than the physiologic vestibular tests. Children with unilateral or bilateral vestibular loss (groups III and IV) showed a more significant balance deficit than children without vestibular loss (group II). The worst balance score was found in children with bilateral vestibular loss. The positive predictive value of the BOT-2 for peripheral vestibular loss in children with SNHL was 88%.ConclusionThe balance subset of the BOT-2 has particularly good predictive values for vestibular loss in children with SNHL. The test is a simple, easy, fast office test which does not require any costly equipment.