BACKGROUND:  Assessment of nystagmus fixation suppression can be used as an additional diagnostic tool for patients with an acute vestibular syndrome to distinguish between a central or peripheral cause. We investigated the ability of physicians to detect fixation suppression using a nystagmus simulation model.
METHODS:  We used a nystagmus simulator to measure the accuracy of the nystagmus fixation suppression test. Fixation suppression was assessed randomly in 6170 trials by 20 otorhinolaryngologists and neurologists, segregated into 2 groups based on their neurootological experience, a beginner and an experienced group. The simulator presented random nystagmus slow velocity (SPV) reductions and presented 3 conditions with either changed nystagmus frequency, amplitude, or both.
RESULTS:  The cutoff for the discernment of fixation suppression ranged from 1.2 to 14°/s nystagmus velocity difference. The more intense the baseline nystagmus was, the more difficult was the detection of fixation suppression. There was not significant difference (P >.05) in the cutoff values in the experts group compared to the novices for all 3 different conditions. Both, novices and experts, detected frequency changes easier than differences of the nystagmus amplitude. Test sensitivity was very low (19%-65%) for discernment of small nystagmus velocity differences of <2°/s by experts.
CONCLUSIONS:  In our study, there was no difference between experts and novices in detection of nystagmus suppression by visual fixation. The examiners could only detect large suppression effects at low-intensity baseline nystagmus. Overall, the sensitivity and accuracy of a clinical fixation suppression test is low and the assistance with a video-oculography device is highly recommended.

OBJECTIVE: Lateral semicircular canal BPPV (LSC-BPPV) is diagnosed with the Head Yaw Test (HYT) by observing nystagmus direction and comparing the nystagmus intensity on both sides according to Ewald\'s laws. Head Pitching Test (HPT) is a diagnostic maneuver performed in the upright position by bending the patient\'s head forward (bowing) and backward (leaning) and observing the evoked nystagmus. We aimed to assess the sensitivity of HPT in correctly diagnosing LSC-BPPV through the quantitative measurement of Bowing and Leaning nystagmus slow-phase velocity (SPV).
METHODS: One hundred cases of LSC-BPPV were prospectively enrolled. HPT was performed, looking for pseudospontaneous, bowing, and leaning nystagmus. HYT was considered for the \"final diagnosis.\" HPT was defined as \"diagnostic\" if the nystagmus was present in at least one position, \"undiagnostic\" if no nystagmus was detectable. The direction and the SPV of nystagmus in all positions were analyzed and compared to determine the degree of agreement between HPT and HYT.
RESULTS: Sixty-four geotropic and 36 apogeotropic forms were diagnosed. HPT was diagnostic in 80 cases, with no difference between the two forms. According to Ewald\'s laws, the direction of stronger nystagmus evoked by HPT agreed with the HYT results in 39/52 (75%) cases in geotropic forms and 21/28 (75%) cases in apogeotropic forms. The agreement between HPT and HYT was \"substantial\" considering all the cases and \"almost complete\" considering only the patients with diagnostic HPT.
CONCLUSIONS: Quantitative HPT is a valid test in diagnosing the affected side and form of LSC-BPPV, even if less reliable than HYT.

BACKGROUND: To improve diagnostic precision in pediatric vertigo, particularly in Vestibular Migraine of Childhood (VMC), probable VMC (pVMC), Recurrent Vertigo of Childhood (RVC), and unspecified categories, by delineating clinical characteristics and prevalence to refine diagnostics and treatments.
METHODS: Retrospective analysis of 102 pediatric patients (five to 18 years; 46 females, 56 males) at the Dizziness Center of the Otolaryngology Department in a tertiary-level hospital from January 2019 to December 2023. Patients were classified into VMC, pVMC, RVC, and indeterminate groups. Evaluations included audiometry and vestibular tests (video head impulse test [vHIT] or caloric testing), conducted in the audiology unit and vestibular testing laboratory. Data were analyzed using IBM SPSS 20.0.
RESULTS: Diagnoses were 8.8% VMC, 31.4% pVMC, 51.0% RVC, and 8.8% indeterminate. Nausea and vomiting were common in VMC and pVMC; cochlear symptoms like tinnitus and hearing loss predominated in VMC. Although vestibular testing showed no significant group differences, VMC had more vHIT abnormalities and RVC had more caloric test anomalies.
CONCLUSIONS: This study highlights the need for comprehensive diagnostics in pediatric vestibular disorders, revealing unique and overlapping traits across VMC, pVMC, and RVC. Insights call for further research to refine diagnostic criteria and improve treatment methods.

BACKGROUND: The subjective visual vertical (SVV) test can evaluate otolith function and spatial awareness and is performed in dedicated vertigo centers using specialized equipment; however, it is not otherwise widely used because of the specific equipment and space requirements. An SVV test smartphone app was developed to easily perform assessments in outpatient facilities.
OBJECTIVE: This study aimed to verify whether the SVV test smartphone app with commercially available virtual reality goggles can be used in a clinical setting.
METHODS: The reference range was calculated for 15 healthy participants. We included 14 adult patients with unilateral vestibular neuritis, sudden sensorineural hearing loss with vertigo, and Meniere disease and investigated the correlation between the SVV test results and vestibular evoked myogenic potential (VEMP) results.
RESULTS: The SVV reference range of healthy participants for the sitting front-facing position was small, ranging from -2.6º to 2.3º. Among the 14 patients, 6 (43%) exceeded the reference range for healthy participants. The SVV of patients with vestibular neuritis and sudden sensorineural hearing loss tended to deviate to the affected side. A total of 9 (64%) had abnormal cervical VEMP (cVEMP) values and 6 (43%) had abnormal ocular VEMP (oVEMP) values. No significant difference was found between the presence or absence of abnormal SVV values and the presence or absence of abnormal cVEMP and oVEMP values; however, the odds ratios (ORs) suggested a higher likelihood of abnormal SVV values among those with abnormal cVEMP and oVEMP responses (OR 2.40, 95% CI 0.18-32.88; P>.99; and OR 2, 95% CI 0.90-4.45; P=.46, respectively).
CONCLUSIONS: The SVV app can be used anywhere and in a short period while reducing directional bias by using virtual reality goggles, thus making it highly versatile and useful as a practical otolith dysfunction screening tool.

OBJECTIVE: This study aimed to correlate the symptoms and signs with the findings of laboratory vestibular function tests in patients with spinocerebellar ataxia (SCA).
METHODS: We retrospectively recruited 26 patients with SCA (9 men, median age: 52, age range: 21-67). Assessments included Dizziness Handicap Inventory, EuroQoL Five-Dimension, symptom questionnaires manifesting during walking in daily life, the Scale for the Assessment and Rating of Ataxia (SARA), and vestibular function tests including 3D video-oculography, video head impulse test, subjective visual vertical, and cervical and ocular vestibular evoked myogenic potentials (VEMP).
RESULTS: Cross-analyses revealed that the patients with VEMP abnormalities showed higher SARA (p = 0.014) and prevalence of unpredictable falls (p = 0.046). The patients with SCA1 more frequently had unpredictable falls (75%, p = 0.038) and VEMP abnormalities (88%, p = 0.001) compared to SCA2 (29% falls, 17% VEMP abnormalities) and SCA6 (no falls or VEMP abnormalities).
CONCLUSIONS: Abnormal VEMPs are strongly associated with unpredicted falls in patients with SCA, particularly in those with SCA1. Impaired processing of otolithic information may contribute to falls in SCAs, and VEMP may help identifying the patients with a risk for unpredicted falls and preventing fall-related injuries in SCA. Limited number of patients with lower SARA scores warrant further confirmatory studies.

UNASSIGNED: To compare vestibular outcomes in cochlear implant (CI) surgery, between robotic-assisted insertion of the electrodes versus manual insertion.
UNASSIGNED: 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.
UNASSIGNED: 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.
UNASSIGNED: 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.

UNASSIGNED: The Dix-Hallpike test is recommended to diagnose Benign Paroxysmal Positional Vertigo (BPPV). This research aimed to quantify the movement of a healthy subject during the Dix-Hallpike test and determine what factors contribute to performance variation from the recommended head position with 20° cervical extension, 45° cervical rotation, and a brisk movement velocity.
UNASSIGNED: Examiners performed the Dix-Hallpike test 10 times. The examinee\'s movement was recorded with Qualisys and processed with Visual3D. The proportion of variation in test performance within examiners, between examiners, and due to examiner position was calculated.
UNASSIGNED: Thirteen participants, 54% male and mean age 40, performed 50 cranial and 77 lateral Dix-Hallpike tests. Head position differed significantly from the recommendations with the cranial tests for extension (mean difference [MD] = 11.6°, p < 0.001) and rotation (MD = 4.8°, p < 0.001) and with lateral tests for extension (MD = 13.3°, p < 0.001). The largest proportion of variation was between examiners (60-91%), followed by within-examiners (3-16%). The examiner position contributed to 20% of the variation in the cervical rotation achieved. Tests lasted, on average, 1.80 s.
UNASSIGNED: Differences within and between examiners visually estimating the Dix-Hallpike test endpoints may impede BPPV diagnosis accuracy.
Vertigo diagnosis with the Dix-Hallpike may be improved by reducing inter-examiner differences with head positioning and velocity.With Dix-Hallpike testing, examiners should consider a cranial orientation relative to the examinee to better achieve the recommended head positioning.The cranial Dix-Hallpike and encouraging briskness as tolerated by the examinee should be emphasized with teaching the maneuver.

暂无摘要。

Video head impulse test (vHIT) and videonystagmography (VNG) provide significant benefits in evaluating benign paroxysmal positional vertigo (BPPV) and determining the semicircular canal localization of the otoconia.
This study aimed to investigate the relationship between vestibular-ocular reflex (VOR) gains measured via vHIT and the slow-phase velocity (SPV) of nystagmus in patients with the posterior semicircular canal (PSCC)-BPPV.
Sixty-two patients were included in this study and divided into the study (n = 32, patients with isolated PSCC-BPPV) and control (n = 30, age- and sex-matched healthy individuals) groups. While VOR gains were measured with vHIT in both groups and compared between groups, the SPV values of nystagmus observed during the Dix-Hallpike maneuver in the study group were recorded using VNG and compared with the VOR gains of the study group.
There were significant differences in posterior canal VOR gains between the study and control groups (p < 0.001 and p < 0.01, respectively). Although the affected PSCC had decreased VOR gains versus the control group, it was still within the normal range. However, there was no significant relationship between the VOR gains of the affected PSCC and the SPV of the nystagmus.
vHIT can help detect semicircular canal dysfunction in patients with PSCC-BPPV. The SPV values of nystagmus on VNG during the Dix-Hallpike maneuver do not correlate with the level of VOR gain.

Current clinical practice considers the vestibulo-ocular reflex (VOR) gain as registered by the video head impulse test (vHIT) as the primary measure for semicircular canal function, while the role of the re-fixation saccades (RSs) is still under evaluation. The goal of the study was to appraise the added benefit of RS towards the improvement of vHIT diagnostic accuracy in cases of suspected left horizontal semicircular canal dysfunction.
The vHIT recordings of 40 patients with left-sided horizontal VOR gains <0.8 were retrospectively evaluated for the presence of RS. The study groups included 20 patients with a final diagnosis of left horizontal semicircular canal dysfunction and 20 patients for whom vestibular dysfunction was ruled out.
Gain values >0.72 were found in all patients with no vestibular disease and in 4 (20%) patients having vestibulopathy. Significantly higher average left-sided RS velocity and frequency were found among the vestibular patients. VOR gain <0.72 was found to be highly specific for the diagnosis of vestibular dysfunction. However, for gain values in the range of 0.72-0.79, the presence of RS with frequency >80% largely improved vHIT diagnostic accuracy.
Although VOR gain <0.8 is considered to reflect dysfunction, a significant false-positive rate for left-sided horizontal vHIT was found for gains in the range of 0.72-0.79. The presence of RS with frequency >80% could improve vHIT diagnostic ability in these patients.