High-Frequency Vestibular Function Is Vulnerable to Presbyvestibulopathy.

INTRODUCTION: In 2019, mild vestibular function deficiency in elder populations was defined as presbyvestibulopathy (PVP) by the Classification Committee of the Bárány Society. The diagnostic criteria include tests for low-, mid-, and high-frequency vestibular function, represented by caloric testing, rotary chair testing, and head impulse testing, respectively. However, there is still a lack of large-scale reports supporting the relationship between vestibular function tests (VFTs) and aging. In this study, we evaluated whether each test is correlated with aging in the elderly population aged over 50. METHODS: This study retrospectively enrolled 1043 subjects from a single university hospital database after excluding those with unilateral and bilateral vestibulopathy, central dizziness, and acute dizziness. Enrolled subjects had caloric canal paresis <20%, vHIT lateral canal gain >0.6, vHIT interaural difference <0.3, and age >50 years old. RESULTS: Significant negative correlations with age were identified in the vHIT (p < 0.001) and rotary chair test (RCT) 1.0 Hz gain (p = 0.030). However, the caloric test (p = 0.739 and 0.745 on the left and right sides, respectively) and RCT 0.12 Hz gain (p = 0.298) did not show a significant correlation with age. A total of 4.83% of subjects aged 70 years or older showed sub-normal vHIT gain that met the criteria of PVP, whereas only 0.50% of subjects aged 60 to 69 did. The prevalence of sub-normal caloric test results, however, was not significantly different between the two age groups (21.55% in the 60-69 age group and 26.59% in the >70 age group). CONCLUSIONS: The high-frequency range vestibular function seems vulnerable to aging, and this is more discernible at age >70 years. The weak correlation between age and low-frequency vestibular function tests, such as the caloric test and low-frequency rotary chair testing, suggests the need to revisit the diagnostic criteria for PVP.

Presence of Spontaneous Nystagmus, Benign Paroxysmal Positional Vertigo, and Tumarkin Fall in Patients With Primary Headache and Their Responses to Caloric and Video Head Impulse Tests.

Background: Migraine, vestibular migraine (VM) and tension-type headache (TTH) are the most common disorders in dizziness and headache clinics, associated with dizziness or vertigo and postural imbalance, causing a substantial burden on the individual and the society. The objective of this research was to examine the presence of spontaneous nystagmus, comorbidity of benign paroxysmal positional vertigo (BPPV), and Tumarkin fall in patients; additionally, the study focused on assessing the patients' responses to bithermal caloric irrigation and video head impulse test (vHIT). Methods: Consecutive patients diagnosed with migraine, VM, and TTH according to the International Classification of Headache Disorders, third edition (beta version (ICHD-3ß)), who were referred to Dizziness and Headache Clinic were enrolled. BPPV and Tumarkin fall were assessed by questionnaires. The presence of BPPV was further evaluated through Dix-Hallpike or head roll maneuver, while spontaneous nystagmus was monitored using video-oculography during interictal period. Lastly, patients' responses to bithermal caloric irrigation and vHIT were analyzed. Results: There was a significantly higher incidence of spontaneous nystagmus in VM compared to both migraine and TTH. The drop attack episodes were slightly more frequent in VM than in TTH and migraine, though not statistically significant. The prevalence of BPPV was significantly higher in VM than in migraine and TTH. Unilateral vestibular paresis was more common in the VM group than in migraine and TTH. There was profound unilateral weakness (UW) in VM patients than in migraine, but no significant difference was found between VM and TTH. In VM, the percentage of saccades along with reduced vHIT gain was significantly higher than in migraine. Lastly, the percentage of abnormal response in vHIT was significantly lower than the percentage of abnormal UW in caloric irrigation across all groups. Conclusions: In VM patients, the prevalences of decompensated peripheral damage and BPPV were higher than in migraine and TTH patients as disclosed by the presence of peripheral spontaneous nystagmus and abnormal vHIT during the interictal period. Our findings suggest that the peripheral vestibular system acts as a significant mechanism in the pathogenesis of VM, and it might also be involved in migraine and TTH cases without vertigo symptoms.

Clinical characteristics and lateralization of the horizontal semicircular canal light cupula.

Introduction: Positional vertigo and nystagmus are the main symptoms and signs of dizziness, respectively. Despite the clinical utility of the supine roll test (SRT) and null point (NP) in diagnosing light cupula, a type of positional vertigo, there exists a notable gap in the literature concerning the comprehensive evaluation of lateralization values based on various nystagmus characteristics and the intensity of direction-changing positional nystagmus (DCPN) in the SRT, particularly in comparison to the NP. Additionally, limited data on abnormal canal paresis (CP) in light cupula patients underscores the need for further research with a larger patient population to elucidate this mechanism. This study aims to investigate the characteristics of positional nystagmus and lateralization of the horizontal semicircular canal (HSCC) light cupula, which is a type of positional vertigo and nystagmus that is poorly understood. Methods: Eighty-five patients (17 males, 68 females; mean age, 60.9 years) with light cupula were reviewed. We summarized the characteristics of spontaneous nystagmus and positional nystagmus, including supine positioning nystagmus, bow nystagmus, and lean nystagmus. Then, the side of the NP was identified as the affected side, and the values of the fast phase direction of the spontaneous nystagmus, supine positioning nystagmus, bow nystagmus, and lean nystagmus, as well as the intensity of the DCPN in the SRT, were used to diagnose the affected sides. Caloric testing was also performed for some patients. Results: Light cupula was observed in 5.7% of the patients with positional nystagmus. The frequencies of supine positioning nystagmus (88.2%), bow nystagmus (90.6%), and lean nystagmus (83.5%) were higher than spontaneous nystagmus (61.2%) (p < 0.001). The second NP (NP2) (92.9%) and third NP (NP3) (83.5%) were readily detected, affecting the left and right sides in 38 and 47 patients, respectively. Lateralization through the fast phase directions of bow nystagmus and lean nystagmus did not significantly differ from that of NP (all p > 0.05). However, the accuracy rate of lateralization through the sides with more vigorous DCPN in the SRT was 63.5%, significantly lower than through NP (p < 0.001). Particularly in patients with supine positioning nystagmus (n = 75), the rate was only 58.7% (p < 0.001). However, the rate was 100% in patients without supine positioning nystagmus (n = 10). Among the 70 patients who underwent caloric testing, 37 had abnormal CP, and the sides of the reduced caloric reaction were ipsilateral to the affected sides of the light cupula in 83.8% of the patients. Conclusion: Besides utilizing the NP to determine the affected side, the fast phase direction of the bow nystagmus or lean nystagmus can also aid in identification. However, a simple comparison of the intensity of DCPN in SRT cannot provide accurate lateralization, especially in patients with supine positioning nystagmus. There is a high incidence of CP on the affected side of the light cupula.

The correlation of hearing prognosis and caloric test results in Meniere's disease: a follow up study.

BACKGROUND: Hearing loss is important in the diagnosis and treatment of Meniere's disease (MD). However, little is known about the factors associated with hearing changes in MD. AIMS/OBJECTIVES: This study aimed to investigate the correlation between hearing prognosis and caloric test (CT) results in MD. MATERIAL AND METHODS: Ninety consecutive patients diagnosed with unilateral definite MD underwent pure tone audiometry (PTA) and CT at initial visits, and were re-tested PTA at the 6-month follow-up. RESULTS: Fifty-three of ninety MD patients (58.89%) had abnormal CT results. The change of PTA (cPTA = initial PTA-last PTA) was negatively correlated with canal paresis (CP) values (overall association p = 0.032 and non-linear association p = 0.413). Multivariate linear model showed that as the CP value changed from 0 to 1, the cPTA decreased by -13.31 dB (95% CI: -24.03, -2.6) (p = 0.016). Stratified analysis found that the association was present in MD patients of Stage 1 and 2 (p < 0.05) but not in patients of Stage 3 and 4 (p > 0.05). CONCLUSIONS AND SIGNIFICANCE: Elevated CP values may be linked to worse hearing outcomes in MD, especially in Stage 1 and 2 patients. Conducting a caloric test at the initial consultation may aid in assessing hearing regression in MD.

Vestibular Pathology as Early Finding of Friedreich's Ataxia in a 16 Years Old Woman.

Friedreich's ataxia is degenerative disease frequently starting around puberty and it's characterized by a progressive gait ataxia, limb weakness, apparition of Babinsky sign, loss of deep tendon reflex, dysarthria and skeletal deformities. The development of vestibular pathology is common but not completely understood. A 16 years old woman with early vestibular defects in relation to a latter Friedreich's ataxia diagnosis is reported.

Vestibular assessment in children with sensorineural hearing loss: diagnostic accuracy and proposal for a diagnostic algorithm.

Introduction: Vestibular assessment in children with sensorineural hearing loss (SNHL) is critical for early vestibular rehabilitation therapy to promote (motor) development or guide decision making towards cochlear implantation (timing of surgery and laterality). It can be challenging from a clinical viewpoint to decide which vestibular tests should be performed for a pediatric patient. The aim of this study was to evaluate the diagnostic accuracy of several clinically available vestibular tests in children with SNHL, and to provide recommendations for the implementation of vestibular testing of children in clinical practice, to screen for vestibular hypofunction (VH). Methods: A two-center retrospective chart review was conducted. Eighty-six patients between the age of 0 and 18 years were included in this study with SNHL. Vestibular tests included video headimpulse test (VHIT), caloric test (performed at the age of four or higher), rotatory chair and cervical vestibular evoked myogenic potential (cVEMP). A combination of the clinical assessment and (combinations of) vestibular test outcomes determined the diagnosis. The diagnostic quality of tests and combination of tests was assessed by diagnostic accuracy, sensitivity and specificity. Results: VH was diagnosed in 44% of the patients. The VHIT and caloric test showed the highest diagnostic accuracy compared to the rotatory chair and cVEMP. All combinations of VHIT, caloric test and cVEMP showed improvement of the diagnostic accuracy compared to the respective tests when performed singularly. All combinations of tests showed a relatively similar diagnostic accuracy, with the VHIT combined with the caloric test scoring the highest. Adding a third test did not substantially improve the diagnostic accuracy. Discussion: Vestibular testing is feasible and VH is highly prevalent in children with SNHL. A proposed diagnostic algorithm recommends starting with VHIT, followed by cVEMP for children under the age of four, and caloric testing for older children if VH is not confirmed with the first test. Performing a third test is redundant as the diagnostic accuracy does not improve substantially. However, challenges remain, including the lack of a gold standard and the subjective nature of the diagnosis, highlighting the need for standardized testing and increased understanding of VH in this population.

Clinical diagnoses of patients showing caloric inversion.

OBJECTIVES: When 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. METHODS: We 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. RESULTS: Out 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. CONCLUSION: Caloric 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 EVIDENCE: Level 4.

A novel methodology to demonstrate vestibulo-ocular reflex using caloric stimulation in undergraduate physiology laboratory.

The study aims to develop a novel methodology to demonstrate the vestibulo-ocular reflex (VOR) and nystagmus by caloric stimulation in an undergraduate medical physiology laboratory. The experimental setup involved two sets of electrodes: one set positioned laterally to both eyes, and another set positioned vertically over either the right or left eye. The caloric method is used to stimulate ears, which involves irrigation of warm (44°C) and cold (30°C) water into the ears while maintaining a temperature difference of approximately ±7°C from the body temperature. The changes in chorioretinal potential were calibrated to angular displacement by a two-point calibration method, and angular velocity was derived after taking the first-time derivative. The results obtained from the digital data acquisition system were compared to the traditional instrument used in our Otorhinolaryngology Department [Interacoustics Videonystagmography (VNG) System for hospitals, medical grade] for the normal subject's data. No significant differences in angular velocity were noted (P > 0.05). The cold stimuli elicit a more pronounced VOR compared to the warm stimuli. It has been consistently observed that the onset of nystagmus occurs approximately 20 s after irrigation, reaching its peak intensity between 45 and 90 s, and gradually diminishing until it ceases after approximately 200 s. Our developed methodology enables the recording and quantification of nystagmus using easily accessible equipment. This study serves the goal of visualizing the physiological process of VOR and thereby fulfills the goal of an effective teaching tool for demonstrating to undergraduate medical students.NEW & NOTEWORTHY We developed a novel methodology to demonstrate and visualize the most common and important physiological phenomenon like the vestibulo-ocular reflex as a teaching module for undergraduate students.

Vestibular function assessment in Idiopathic sudden sensorineural hearing loss: a prospective study.

PURPOSE: Idiopathic sudden sensorineural hearing loss (ISSHL) can cause acute damage not only to the auditory function, but also to the vestibular function in addition to damage to the hearing function. The aim of this study was to perform vestibular assessment using caloric test and video head impulse test in patients with idiopathic sudden sensorineural hearing loss. In addition, to evaluate the relationship of dizziness with vestibular tests and post-treatment responses of vestibular tests. METHODS: This is an observational, longitudinal and prospective study, including patients diagnosed with idiopathic sudden sensorineural hearing. Patients were divided into two groups according to the presence of vestibular complaints at presentation: Group 1: Patients with vestibular complaints, Group 2: Patients without vestibular complaints. All subjects underwent pure tone audiometry (PTA) testing, cold caloric test and video head impulse test (vHIT) during their admission and on the 10th day, 3rd month, and 1st year of their follow-up outpatient clinic controls. A unilateral weakness (UW) in the caloric test response was quantified according to the Jongkees formula. RESULTS: A positive and significant relationship was found between the degree of hearing loss according to the ASHA criteria pre-treatment and the level of improvement created according to Siegel criteria at the 10th day, 3rd month, 1st year after treatment (respectively p = 0.001, p = 0.001, p < 0.001). When both short-term and long-term results were evaluated after treatment, a positive improvement in the degree of hearing loss was observed. A statistically significant difference was observed between Groups 1 and 2 when the pre-treatment, at 10 days, 3 months and 1 year after treatment the caloric test UW value was compared (respectively p = 0.020, p = 0.004, p = 0.004, p = 0.004). A statistically significant difference was observed between Groups 1 and 2 when the pre-treatment, at 10 days, 3 months and 1 year after treatment vHIT lateral canal VOR value was compared (respectively p = 0.000, p = 0.001, p = 0.000, p = 0.004). When both short-term and long-term results were evaluated after treatment, a positive improvement was observed in both caloric test results and lateral vHIT VOR values. Pre-treatment, post-treatment 10th day, 3rd month, 1st year vHIT anterior and posterior canal VOR values were found to be VOR˃0.8 in all patients. No difference was observed in anterior and posterior canal VOR values. CONCLUSION: Vertigo in patients with ISSHL "as objectively confirmed through caloric testing and vHIT" can be considered a sign of severe cochlear damage. Our study demonstrated a significantly increased risk of vestibular affect in patients with ISSHL, especially in the presence of vertigo. Thus, we conclude that the focus in ISSHL should not only be on the cochlea but also on the vestibular system.

Impact of endolymphatic hydrops on the function of the horizontal canal during caloric stimulation in Ménière's disease.

PURPOSE: When a dizzy patient with episodic vertigo has an abnormal caloric and a normal video head impulse test (vHIT), this caloric-vHIT dissociation provides vital information for a diagnosis of Ménière's disease (MD). Endolymphatic hydrops (EH), a histological marker of MD, is hypothesized to be involved in the caloric-vHIT dissociation in MD through hydropic duct distension of the horizontal semicircular canal (SC). This study was designed to determine the impact of EH on the function of horizontal SC during caloric stimulation. METHODS: Caloric test and vHIT were used to evaluate the function of horizontal SC every six months, annual magnetic resonance imaging (MRI) was used to evaluate the degree of EH size in the vestibule, and monthly vertigo and hearing evaluation was done for 12 months. EH shrinkage was defined as the size change of vestibular EH from significant to none. RESULTS: Among 133 MD patients evaluated for eligibility, 67 patients with caloric-vHIT dissociation entered the study. Fifteen participants had EH shrinkage (G-I), while 52 participants had no remarkable EH change (G-II). Average values (IQR) of the maximum slow phase velocity in G-I and G-II were 29.6 (13.0-34.0) and 25.9 (17.3-31.3), respectively, at baseline, 26.1 (9.0-38.0) and 23.6 (18.0-28.3) at 12 months. Two-factor repeated-measures ANOVA showed no significant differences between the groups (P = 0.486). The values of vestibulo-ocular reflex gain of the horizontal SC in G-I and G-II remained above 0.8 during the study period. CONCLUSIONS: EH detected by MRI shows limited correlation with caloric stimulation results.

Estimated incidence and characteristics of vestibular neuritis in Japan: A nationwide survey.

OBJECTIVE: To assess the annual incidence of vestibular neuritis (VN) in the Japanese population. METHODS: We conducted a mail-based survey targeting otolaryngologic clinics and hospitals across Japan to estimate the annual number of patients who were newly-diagnosed with VN during the one-year period of 2021. Using a stratified sampling method, we selected 1,107 departments and asked them to report the number of new patients with VN and their demographics. The total number of VN patients was estimated by multiplying the reported numbers by the reciprocal of the sampling rate and response rate. RESULTS: The overall survey response rate was 40.5 % (448 departments). The estimated number of newly-diagnosed VN patients in 2021 was 8,861 (95 % confidential interval [CI], 2,290-15,432) The annual incidence of VN was 7.05 per 100,000 population in Japan. The male-to-female ratio of VN patients was 0.96, and the mean age was 60.3 ± 16.1 years (range 11-94 years). CONCLUSIONS: The annual incidence of VN in Japan in 2021 had almost doubled and the mean age had become older compared to the previous study in 1993 (annual incidence; 3.5 per 100,000 per year; mean age: 45 years).

Subjective and objective responses to caloric stimulation help separate vestibular migraine from other vestibular disorders.

BACKGROUND: Nystagmus generated during bithermal caloric test assesses the horizontal vestibulo-ocular-reflex. Any induced symptoms are considered unwanted side effects rather than diagnostic information. AIM: We hypothesized that nystagmus slow-phase-velocity (SPV) and subjective symptoms during caloric testing would be higher in vestibular migraine (VM) patients compared with peripheral disorders such as Meniere's disease (MD) and non-vestibular dizziness (NVD). METHODS: Consecutive patients (n = 1373, 60% female) referred for caloric testing were recruited. During caloric irrigations, patients scored their subjective sensations. We assessed objective-measures, subjective vertigo (SVS), subjective nausea (SNS), and test completion status. RESULTS: Nystagmus SPV for VM, MD (unaffected side), and NVD were 29 ± 12.8, 30 ± 15.4, and 28 ± 14.2 for warm irrigation and 24 ± 8.9, 22 ± 10.0, and 25 ± 12.8 for cold-irrigation. The mean SVS were 2.5 ± 1.1, 1.5 ± 1.33, and 1.5 ± 1.42 for warm irrigation and 2.2 ± 1.1, 1.1 ± 1.19, and 1.1 ± 1.16 for cold-irrigation. Age was significantly correlated with SVS and SNS, (p < 0.001) for both. The SVS and SNS were significantly higher in VM compared with non-VM groups (p < 0.001), and there was no difference in nystagmus SPV. VM patients SVS was significantly different to the SVS of migraineurs in the other diagnostic groups (p < 0.001). Testing was incomplete for 34.4% of VM and 3.2% of MD patients. To separate VM from MD, we computed a composite value representing the caloric data, with 83% sensitivity and 71% specificity. Application of machine learning to these metrics plus patient demographics yielded better separation (96% sensitivity and 85% specificity). CONCLUSION: Perceptual differences between VM and non-VM patients during caloric stimulation indicate that subjective ratings during caloric testing are meaningful measures. Combining objective and subjective measures could provide optimal separation of VM from MD.

Clinical diagnoses of patients showing caloric inversion

Abstract Objectives When 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. Methods We 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. Results Out 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. Conclusion Caloric 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 Evidence: Level 4.

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

AIM: 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. METHODS: 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. RESULTS: 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). CONCLUSION: 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.

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

Purpose: 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. Methods: 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. 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. Conclusion: 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.

Meniere Disease treated with transcutaneous auricular vagus nerve stimulation combined with betahistine Mesylate: A randomized controlled trial.

BACKGROUND: Meniere Disease is a clinical condition defined by hearing loss, tinnitus, and aural fullness symptoms, there are currently no any medications approved for its treatment. OBJECTIVE: To determine whether taVNS as an adjunctive therapy could relieve symptoms and improve the quality of life in patients with Meniere disease. METHODS: In this Single-center, single blind, randomized trial, participants were assigned to transcutaneous auricular vagus nerve stimulation (taVNS) group and sham taVNS group. The primary outcome measures comprised Tinnitus Handicap Inventory, Dizziness Handicap Inventory, Pure Tone Auditory, Visual analogue scale of aural fullness. Secondary outcome measures comprised the 36-Item Short Form Health Survey, video head impulse test, and the caloric test. RESULTS: After 12 weeks, the THI (-11.00, 95%CI, -14.87 to -7.13; P < 0.001), DHI (-47.26, 95%CI, -50.23 to -44.29; P < 0.001), VAS of aural fullness (-2.22, 95%CI, -2.95 to -1.49; P<0.01), and Pure Tone Thresholds (-7.07, 95%CI, -9.07 to -5.06; P<0.001) were significantly differed between the two groups. In addition, SF36(14.72, 95%CI, 11.06 to 18.39; P < 0.001), vHIT (RD, 0.26, 95 % CI, -0.44 to -0.08, RR, 0.43, 95 % CI, 0.22 to 0.83, P < 0.01), and the caloric test (RD, -0.24, 95 % CI, -0.43 to -0.04, RR, 0.66, 95 % CI, 0.44 to 0.95, P = 0.02) have significant difference between two group, respectively. CONCLUSIONS: These findings suggest that taVNS combined with Betahistine Mesylate relieve symptoms and improve the quality of life for patients with Meniere Disease. taVNS can be considered an adjunctive therapy in treatment of Meniere Disease. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT05328895.

Impact of Endolymphatic Hydrops and Semicircular Canal Dysfunction on the Incomplete Recovery of Acute Low-Frequency Sensorineural Hearing Loss.

OBJECTIVE: The reasons for short-term, incomplete recovery of some acute low-frequency sensorineural hearing loss (ALFHL) are unclear. We investigated the impact of endolymphatic hydrops and semicircular canal dysfunction on the incomplete recovery of ALFHL. METHODS: The impact of electrocochleography (EcochG), caloric test, video head impulse test (vHIT), cervical vestibular-evoked myogenic potential (cVEMP), and ocular vestibular-evoked myogenic potential (oVEMP) results on the incomplete recovery of 86 patients with ALFHL was analyzed. The correlation between a high abnormal rate of vestibular-evoked myogenic potential (VEMP) and aural fullness, dizziness, and level of hearing loss was also examined. RESULTS: Abnormal oVEMP with an odds ratio (OR) of 6.071 (P = .002) and EcochG with an OR of 5.919 (P = .005) were independent risk factors for incomplete recovery in ALFHL, but abnormal cVEMP, caloric test, and vHIT were not independent risk factors for ALFHL. There was no correlation between a high abnormal rate of VEMP and aural fullness, dizziness, or level of hearing loss in ALFHL. CONCLUSION: Abnormal oVEMP and EcochG values rather than caloric test and vHIT were risk factors for incomplete recovery of ALFHL, which may be related to the difficulty of successfully treating utricular and cochlear hydrops. High abnormal rate of VEMP was not correlated with hearing loss level, aural fullness, or dizziness in ALFHL. Abnormal oVEMP and EcochG values can indicate poor short-term prognosis of ALFHL.

Dissociation between video head impulse test and caloric test: a marker of menière's disease? - A systematic review and meta-analysis.

OBJECTIVE: To analyze, by means of a systematic review and meta-analysis, the proportion of patients with Meniere's disease who have altered caloric test and vHIT, as well as to determine the prevalence of altered caloric test and normal vHIT dissociation in the diagnosis of Meniere's disease. METHODS: The literature search had no restriction regarding the period of publication on the following indexed data platforms: PubMed, PubMed PMC, BVS-Bireme, Web of Science, Embase and Cochrane Library. Articles that evaluated patients with Meniere's disease who underwent caloric test and vHIT were included. Two researchers independently conducted the analysis of the articles, promoting the selection and capture of data, following the recommendations of the PRISMA method, and complying with the criteria for articles inclusion and exclusion defined in the research protocol. In case of disagreement during the selection process, a third researcher was included for analysis. RESULTS: From a total of 427 initial studies, the researchers selected 12 articles, published between 2014 and 2021, with a total of 708 patients evaluated, with a mean age of 52.72 years old. The prevalence of patients with Meniere's disease with altered caloric reflex test was 64% (95% CI 57%‒71%), while the prevalence of altered vHIT was only 28% (95% CI 16%-40%). The prevalence of the altered caloric test + normal vHIT dissociation was 47% (95% CI 37%-57%). CONCLUSION: The video head impulse test and the caloric test are valuable tools for vestibular assessment. The dissociation of findings between these two tests in patients with Meniere's disease was more prevalent in this meta-analysis and may be a result of the tonotopy of specialized hair cells in the ampullary crest. The prevalence of altered caloric test was 64% and anormal vHIT was 28%. The dissociation caloric asymmetry and normal vHIT was observed in 47% of the patients.

Vestibular Tests Related to Tumor Volume in 137 Patients With Small to Medium-Sized Vestibular Schwannoma.

OBJECTIVE: The video head impulse test (vHIT) and cervical and ocular vestibular evoked myogenic potentials (cVEMP and oVEMP) are new methods for measuring peripheral vestibular function. The objectives of this study were to compare these tests and the traditionally used caloric test in patients with small and medium-sized untreated vestibular schwannoma (VS) and to measure the correlation between the tests' results and tumor volume. STUDY DESIGN: National cross-sectional study. SETTING: Tertiary university clinic. METHODS: Prevalence of abnormal cVEMP, oVEMP, caloric test, and 6-canal vHIT results on the tumor side and the nontumor side were compared and related to tumor volume with regression analyses in 137 consecutive VS patients assigned to a wait-and-scan protocol in the period 2017 to 2019. RESULTS: The sensitivity of 6-canal vHIT, caloric test, cVEMP, and oVEMP to detect vestibulopathy in VS patients was 51%, 47%, 39%, and 25%, respectively. Normal tests were found in 21% of the patients. The results of vHIT and caloric test were related to tumor volume, but this was not found for cVEMP and oVEMP. CONCLUSION: The caloric test and 6-canal vHIT showed the highest sensitivity in detecting vestibulopathy in untreated VS patients. vHIT, and particularly the posterior canal, was limited with a high prevalence of abnormal results on the nontumor side. A combination of cVEMP and caloric test was favorable in terms of a relatively high sensitivity and low prevalence of abnormal results on the nontumor side. Larger tumors had a higher rate of pathology on caloric testing and vHIT.