Benign paroxysmal positional vertigo (BPPV) is a common vestibulopathy and involves failed dissolution and dislocation of calcium carbonate crystals into the semicircular canal. This causes short-lasting vertigo during changes in head position. Oftentimes, BPPV can be resolved within a single clinic visit, but secondary to many known risk factors, BPPV can recur. This case report follows a patient with extremely frequent recurrences despite a lack of known risk factors. A 55-year-old female experienced BPPV in December 2022, with successful canalith repositioning treatment from otolaryngology. On having a recurrence in March 2023, the patient underwent videonystagmography including caloric testing, and MRI, all of which showed normal findings besides left posterior-canal BPPV. From December 2022 to February 2024, the patient had 13 recurrences, each treated to resolution, confirmed by repeating positional tests and per subjective report for at least 2 weeks following. The incidence of BPPV recurrence is reported higher in females, however, this could not be interpreted as a causative factor. Though many other risk factors are documented in literature, this patient\'s history, demographics, imaging, and blood tests were all negative. This case report highlights a gap in knowledge of vestibular pathophysiology, as this patient\'s high rate of recurrence remains unexplained.

Patients with the cardinal symptoms \"vertigo\" or \"dizziness\" may be a real challenge for the treating otorhinolaryngologist. While the first part of this educational series was focused on history taking and bedside neurotological examination, the present paper is devoted to difficult aspects of vestibular laboratory testing, including getting the indication right, what to do if my patient is not able to fully cooperate during the tests, how to choose the adequate diagnostic procedure depending on the patient\'s comorbidities, how to interpret discordant results of various tests. Finally the paper addresses which conclusions can be drawn (and cannot be drawn) from normal findings in vestibular testing and how to communicate this result to the dizzy patient.
UNASSIGNED: Patient:innen mit dem Leitsymptom „Schwindel“ stellen häufig eine diagnostische Herausforderung für die betreuenden Hals-Nasen-Ohren-Ärzt:innen dar. Während im ersten Teil dieser Fortbildungsreihe der Fokus auf der Anamnese und klinisch-neurootologischen Untersuchung lag, behandelt der vorliegende zweite Teil wichtige Aspekte der „schwierigen“ apparativen Vestibularisprüfung, insbesondere: Indikationsstellung, Lösungsansätze bei eingeschränkter Kooperationsfähigkeit der Patient:innen, Auswahl der vestibulären Tests in Abhängigkeit von Komorbiditäten, Interpretation von diskrepanten Befunden aus einzelnen Teiluntersuchungen. Des Weiteren wird dargelegt, welche Schlussfolgerungen aus einer normwertigen Vestibularisprüfung gezogen werden können (und welche nicht) und wie dieses Ergebnis den Patient:innen erläutert werden kann.

OBJECTIVE: 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.
CONCLUSIONS: 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.
METHODS: Level 4.

BACKGROUND: 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.
METHODS: 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.
RESULTS: 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).
CONCLUSIONS: 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.

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.
OBJECTIVE: 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).
CONCLUSIONS: 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.

OBJECTIVE: Patients often have basic audiometry (BA) but not objective diagnostic tests of the vestibular system (VNG) when complaining of symptoms of a vestibular disorder. The relationship of BA results to VNG results is unknown. This study sought to determine if BA scores are related to impaired VNG scores.
METHODS: We reviewed electronic medical records at a tertiary care center, for patients seen between 2015 and 2021 who had had both a BA and a VNG (n = 651). BA subtests were pure tone averages, word recognition, and tympanogram. VNG subtests were cervical vestibular evoked myogenic potentials, Dix-Hallpike maneuvers, and bi-thermal caloric tests. All tests were summarized as normal/abnormal.
RESULTS: More subjects had abnormal BA than abnormal VNG scores. Age but not sex was significantly related to abnormal scores. High BP was a significant comorbidity in 15 % of the sample, more in patients with abnormal than normal VNG scores. Although the abnormal BA and abnormal VNG were significantly related, pure tone averages and tympanogram scores were not related to VNG subtests. Abnormal word recognition with both ears combined was significantly related to normal and abnormal bi-thermal caloric tests.
CONCLUSIONS: If the clinician needs to know of any VNG impairment, in general, then performing a BA without a VNG might suffice. If the clinician needs information about the details of possible vestibular impairment, then a VNG should be performed.

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%).
CONCLUSIONS: 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.
METHODS:

Persistent postural-perceptual dizziness (PPPD) is induced by preceding conditions that cause balance disorders. To investigate the association between vestibular function and preceding balance disorders in PPPD patients, a retrospective chart review was performed. Vestibular function in 55 PPPD patients was measured using the caloric test, cervical vestibular evoked myogenic potential testing to air-conducted sound (ACS cVEMP), ocular vestibular evoked myogenic potential testing to bone-conducted vibration (BCV oVEMP), and video head impulse testing (vHIT). Patients were classified according to the type of preceding balance disorder. The age-stratified Cochran-Mantel-Haenszel (CMH) test and the exact test for the common odds ratio were conducted to evaluate the association between preceding n ≥ 4 balance disorders and present peripheral vestibular dysfunction. PPPD patients with preceding vestibular neuritis presented a significant positive association with abnormal caloric responses (p = 0.013), while those with preceding benign paroxysmal positional vertigo (BPPV) had significantly lower rates of abnormal BCV oVEMP (p = 0.003). Furthermore, patients with preceding vestibular neuritis showed lateral semicircular canal dysfunction, while those with preceding BPPV presented normal utricular functions. These results present the influence of preceding balance disorders on the vestibular function in PPPD.

Objective:This study was conducted to evaluate the applications of vestibular function tests in diagnosis, identifying tumor origins and prognosis of vestibular rehabilitation of patients with acoustic neuroma. Methods:This research is a single-center cross-sectional clinical study, which retrospectively analyzed the data of 335 patients with acoustic neuroma from March 2013 to March 2020 in the Eye and ENT Hospital of Fudan University. The study included caloric test, cervical and ocular vestibular evoked myogenic potentials（cVEMP, oVEMP）, video head impulse test（vHIT） and sensory organization test（SOT）. Firstly, the sensitivity, specificity, and Yoden index of each test were calculated. Secondly, the internal relevance of these tests was studied for application in judging the origins of the tumor. Results:The abnormal rates of caloric test, cVEMP, oVEMP, vHIT and SOT was 85.3%, 86.1%, 85.5%, 55.6% and 67.7% in these participants. Among all the vestibular function tests included, the caloric test showed the best sensitivity（0.855）, specificity（0.981）, and Yoden index（0.836）. The study found that the higher the Koos grades, the higher the abnormal rates of the caloric test, vHIT, and oVEMP（Cochran-Armitage test, P<0.05）. There was no significant relationship between the combination of abnormal vestibular function tests and tumor origin nerves（P>0.05）. Conclusion:Majorlty of the participants in this study with acoustic neuroma showed abnormal results in SOT related to poor balance control. More than half of the patients had at least two abnormal result of the battery of vestibular function tests, among which the caloric test was proved to have better sensitivity and specificity. The higher the Koos grades of the tumor, the higher the abnormal rates of the caloric test, vHIT, and oVEMP.
目的：通过对听神经瘤患者前庭功能进行多方面评估，探究不同前庭检测技术在前庭功能障碍诊断、代偿建立及肿瘤起源分析中的价值，为听神经瘤患者的前庭功能预后评价及康复策略提供借鉴。 方法：回顾性分析2013年3月—2020年3月复旦大学附属眼耳鼻喉科医院耳鼻喉科收治的335例听神经瘤患者的多种术前前庭功能检查结果，包括温度试验、颈性前庭诱发肌源性电位（cVEMP）、眼性前庭诱发肌源性电位（oVEMP）、视频头脉冲试验（vHIT）及感觉统合试验（SOT），研究其在听神经瘤侧别判断中的灵敏度、特异度和约登指数等，分析各项检查的内部相关性，以及在肿瘤起源判断中的价值，并根据SOT结果对患者前庭代偿情况进行总结。 结果：入组患者中温度试验、cVEMP、oVEMP、vHIT、SOT检查异常率依次为85.3%、86.1%、85.5%、55.6%和67.7%，其中温度试验表现出相对最优的灵敏度（0.855）、特异度（0.981）和约登指数（0.836）。相关性分析结果提示随听神经瘤Koos分级增加，温度试验、vHIT和oVEMP检查异常率也在增加（Cochran-Armitage趋势检验，P<0.05）。各项前庭功能检查异常与对应肿瘤来源神经之间未见显著相关性（P>0.05）。 结论：多数听神经瘤患者术前存在前庭相关平衡障碍。超过50%的患者存在两项及以上前庭功能检查异常，提示前庭功能损伤范围较广。Koos分级越高，患者术前温度试验、vHIT和oVEMP检查异常率也更高。在判断患侧前庭功能异常方面，温度试验相对于cVEMP、oVEMP和vHIT检查显示出更佳的灵敏度与特异度。.

UNASSIGNED: Nonspecific complaints of hearing loss, vertigo, imbalance, and instability, without a defined etiology, are very prevalent in the elderly population, with a great impact on morbidity and mortality in this age group. The objectives of this study were to verify whether there is age-related vestibular dysfunction and to test the association of vestibular dysfunction with presbycusis in the elderly population.
UNASSIGNED: Original retrospective analytical cross-sectional study, carried out with 80 patients who underwent a videonystagmography and complete audiometric evaluation due to nonspecific vestibular complaints, without a specific vestibular disorder diagnosis. Patients were selected and divided into two distinct age groups (group A: >60 years; group B: 18-50 years) and, in both groups, we analyzed the caloric tests and the pure-tone audiometry.
UNASSIGNED: In the vestibular evaluation, we found that there was a statistically significant difference (P < 0.05) between groups in the prevalence of bilateral vestibular weakness (group A: 22.5%; group B: 5%), and that the increase in age, above 60 years, is negatively correlated with the mean total caloric response. Additionally, we obtained a reasonable negative and statistically significant correlation (r = -0.320, P < 0.05) between the mean bone conduction thresholds at high frequencies and total caloric responses in group A.
UNASSIGNED: In patients with hearing loss, it is essential to perform a complete vestibular study to diagnose vestibular disorders and, consequently, prevent adverse outcomes that may result from these alterations.