Journal of Vestibular Research-Equilibrium & Orientation最新文献

BackgroundPositional downbeat nystagmus (pDBN) may have multiple etiologies.ObjectivesDescription of a case series and further considerations about pDBN characteristics, pathogenesis, and differential diagnosis.MethodsDescriptive study concerning 153 consecutive patients with pDBN of presumed peripheral origin that were recruited and observed. They were treated only with Brandt-Daroff Exercises.Results56% reported symptoms of "typical positional vertigo," 44% described postural instability during head movements or a continuous sense of dizziness. 40% of patients were symptom- and nystagmus-free after 1 week and almost 60% after 2 weeks 5% were still affected by pDBN after 1 month. Several pathogenetic hypotheses have been advanced: otoconia in the anterior canal, an apogeotropic variant of posterior canal, or in the short arm of the posterior canal.ConclusionDown-beat nystagmus arising from the semicircular canals must contain a torsional component and be in "canal-plane" - presenting more torsional when gaze is towards the affected canal, and more purely vertical when directed away, whereas central causes of DBN may be "pure" down-beat. Peripheral pDBN is fatigable, often no nystagmus when returning in sitting position and, highly relevantly, it is self-limiting (95% disappears with only Brandt-Daroff Exercises), with no central signs. Patients may complain of long-term dizziness, trunk oscillation, and prolonged motion sickness. New guidelines may consider the term of Down-Beating BPPV or Down-Beating peripheral positional vertigo, even if the otoconia's exact position is still uncertain: in our opinion pDBN might be considered as an "apogeotropic variant of PC-BPPV".

BackgroundSensory impairments such as hearing loss and vestibular disorders can affect spatial cognition.ObjectiveThis study assessed the spatial cognitive abilities of cochlear implant (CI) users with hearing loss and compared them based on otolith functions.MethodsThe study has a control group and two subgroups. The first study group had 19 CI users with otolith dysfunction, and the second had 21 without. The control group had 20 healthy, age-, gender-, and education-matched volunteers. The triangle completion task (TCT), the spatial orientation test (SOT), and the four mountains test assessed spatial ability.ResultsResearch indicates that CI users with otolith dysfunction had significantly larger deviation angles and distances in TCT compared to healthy controls (p < .001). Statistically significant differences in SOT were found between groups (p < .001). Healthy controls had the lowest SOT score, whereas CI users with otolith dysfunction had the highest. In 4 MT, CI users with and without otolith dysfunction had more mistakes than controls (p < .05).ConclusionsResearch shows that otolith information is important for path integration and spatial navigation, and hearing loss worsens spatial memory degradation. These impairments impede spatial skills, which are essential for daily tasks like shopping and driving and for spatial memory, learning, and navigation.

ObjectivesPeripheral vestibular hypofunction (PVH) affects a significant portion of the population and impairs visual acuity during head motion (dynamic visual acuity, DVA). This study compared the effectiveness of a novel gaze stability training called Incremental VOR Adaptation (IVA) versus traditional vestibular physical therapy (VPT) for improving DVA.MethodsThe Incremental Velocity Error as a New Treatment in Vestibular Rehabilitation (INVENT) trial is a randomized, controlled, cross-over study involving 24 participants with chronic unilateral or bilateral PVH. Participants underwent either IVA or VPT for 3 weeks, followed by a washout period and then the alternate intervention (IVA-VPT or VPT-IVA). DVA was measured at baseline, after each intervention, at the completion of the washout period, and at 6-month follow-up.ResultsThere was a significant main effect of treatment Group, F (1,19) = 7.75, p = 0.012, with (IVA-VPT) consistently demonstrating lower DVA scores than VPT-IVA. A significant main effect of Side was also observed, F (1,19) = 13.35, p = 0.0017, indicating lower DVA scores for contralesional compared to ipsilesional head rotation. We found no effect of Time (F (4,76) = 1.44, p = 0.23), suggesting that scores remained stable from baseline through the 6-months follow-up. There were no significant interactions, including Group × Side (F (1,19) = 0.11, p = 0.74), Group × Time (F (4,76) = 1.33, p = 0.27), or Group × Side × Time (F (4,76) = 0.59, p = 0.67).ConclusionDVA scores were consistently better at all time points after participants completed IVA. Using an intent to treat analysis, with no baseline demographic differences between groups, our data support that exposure to the first gaze stability training type exerts a stable influence on DVA that persisted to 6-month follow-up. Clinically, this implies that once DVA improvements are established through either IVA or VPT, they tend to remain stable over 6 months.Level of EvidenceLevel 2.

BackgroundPatients with persistent postural-perceptual dizziness (PPPD) suffer from symptoms of chronic dizziness that exacerbate in a moving environment. However, not much is known regarding gaze behavior in a static condition. The present study investigated gaze stability under static visual stimuli in patients with PPPD.MethodsThree groups of participants were recruited; 22 PPPD, 9 Ménière's disease (MD) and 19 healthy participants (HC). Participants were asked to undergo a free viewing test of emotionally neutral images through a virtual reality headset with a gaze-recording system. Bivariate Contour Ellipse Area (BCEA), a measure for gaze stability, and saliency values at points of gaze fixations were measured.ResultsPPPD showed smaller BCEA compared to MD and HC, with high anxiety state being a possible confounding factor. There was no difference in saliency values between all three groups.ConclusionsPPPD, MD, and HC all tended to fixate on salient parts of the images, but in PPPD, gaze was restricted to a smaller area compared to MD and HC. Considering that previously reported studies on PPPD patients showed gaze instability under dynamic stimuli, the gaze behavior from the present study, involving static stimuli, may reflect the opposite pole to that of dynamic stimuli.

BackgroundSubjective visual vertical (SVV) test is a key functional assessment tool that provides insights into vestibular imbalance. Mobile virtual reality SVV measurement system (MVR-SVV) has the potential to facilitate simple, low-cost, and reliable measurements.ObjectiveThis study aimed to verify the reliability and validity of MVR-SVV by comparing its data with the previously established bucket test (bucket-SVV).MethodsThirty-eight healthy adults completed both bucket-SVV and MVR-SVV tests. The reliability and validity of MVR-SVV were examined using intraclass correlation coefficients (ICCs), Pearson's correlation, Bland-Altman plots (BAP), and minimum detectable change (MDC).ResultsBAP results indicated that the limits of agreement for the SVV angles were 1.61 to -1.24°. No fixed errors were identified (p = 0.13), although a small proportional error was detected (y = -0.59x + 0.157, p < 0.001). Pearson's correlation coefficient between bucket-SVV and MVR-SVV was 0.716 (p < 0.001). Within-day reliability was poor for bucket-SVV, with ICC = 0.33-0.38, but moderate for MVR-SVV, with ICC = 0.70-0.71. Between-day reliability was poor for both methods, with ICC = 0.38 for MVR-SVV and ICC = 0.28 for bucket-SVV. MDC was 1.78° for bucket-SVV and 2.67° for MVR-SVV.ConclusionsOur findings suggest that MVR-SVV can be used for assessing SVV. Its portability, availability, and reliability make it a valuable tool for clinicians in clinical settings.

ObjectivesKinesiophobia is the condition in which the patient restricts their movements and activities because of the fear of being injured again after a painful experience. Numerous studies have found kinesiophobia in patients with vestibular disorders. This research study aimed to develop and measure the psychometric properties of the Tampa Scale of Kinesiophobia (TSK-11), for use in persons with dizziness (TSKd).MethodsAn observational validation study of questionnaires was carried out including 211 participants with dizziness. After adapting the TSK-11 items to the symptoms of dizziness, the construct validity was evaluated with principal component analysis (PCA), internal consistency with the calculation of Cronbach's alpha, test-retest reliability with the intraclass correlation coefficient (ICC), concurrent validity with Spearman correlation and predictive validity with ROC curve analysis.ResultsThe PCA retained 10 items from the original scale with a three-factor structure that mediates fear (TSKd_f), negative thoughts (TSKd_n) and avoidance (TSKd_a). Cronbach's alpha was 0.810 for the 10-item TSKd. Reproducibility was moderate to substantial, with ICCs between 0.69 and 0.84. The TSK showed strong correlations with the DHI, while correlations with other dizziness measures were moderate. A TSKd score >25 and TSKd_f score >9 showed good predictive capacity, with an area under the curve (AUC) ROC of 0.85 and a sensitivity and specificity between 0.85 and 0.70.ConclusionsThe TSKd is a tool available for measuring kinesiophobia in persons with dizziness. Both the 10-item TSKd and the 4-item TSKd_f scales have good psychometric properties.

BackgroundThe computerized rotational head impulse test (crHIT) employs whole-body impulsive rotations like the angular motion used in the video head impulse test (vHIT) to assess the function of all semicircular canals (SCCs).ObjectiveThis study utilized vertical crHIT and vHIT among healthy subjects to evaluate the effectiveness of these tools in assessing SCC function.MethodsThirty-five individuals with no history of vestibular disorders or traumatic brain injury were enrolled in this study. Participants underwent vHIT (ICS Impulse Otometrics) and crHIT (Neuro-Otologic Testing Center, Spryson America, Inc.).ResultsMean VOR gain was significantly higher during crHIT compared to vHIT, except for the right horizontal SCC (p < 0.01). Coefficient of variation (CV) for crHIT was smaller than that observed in vHIT across all 6 SCCs, with significant differences in all but the LA and RP SCCs. We also computed lower limits of normal (LLN) for each condition; up to 2.9% of crHIT values fell outside the acceptable LLN compared to up to 37% of vHIT gain values. Average reduced vestibular response (RVR) for crHIT was lower than that observed in vHIT among all semicircular canal pairs and demonstrated less variability for crHIT as compared to vHIT.ConclusionsOverall, these findings support the clinical utility of crHIT for comprehensive SCC function evaluation.

We report a case of paroxysmal downbeat nystagmus, ataxia, and dysarthria in the context of a delirium in a patient with severe hypomagnesemia. Extensive workup did not provide alternative explanations. Her attacks subsided within 48 h after the start of magnesium substitution and the patient remained confused and ataxic with a gradual but full recovery over 6 weeks. Hypomagnesemia resulted most probably from long-term proton-pump inhibitor (PPI) intake. Paroxysmal downbeat nystagmus is rare and has so far only been consistently described in association with hypomagnesemia of various causes.

PurposeBalance and vestibular disorders have a profound impact on quality of life. Anxiety (ANX) and depression (DEP) are common with dizziness, vertigo, or imbalance. It is unclear whether self-reported anxiety or depression depends on perceived physical function for individuals participating in vestibular rehabilitation (VPT). We hypothesized that individuals with worse physical function would be more likely to report abnormally high anxiety and/or depression levels.Participants170 individuals referred for vestibular rehabilitation (113 female, 57 males, and age 63.7 (21)).MethodsA retrospective chart review extracted age, Patient-Reported Outcome Measurement Information System (PROMIS) scores (ANX, DEP, physical function) and primary diagnoses [benign paroxysmal positional vertigo (n = 42), unilateral vestibular hypofunction (n = 39), bilateral vestibular hypofunction (n = 14), concussion/head injury (n = 7), dizziness/vertigo (n = 37), and imbalance (n = 31)]. Average PROMIS scores and percentage of abnormal scores were calculated for physical function, ANX, and DEP scores and reported using descriptive statistics. Logistic regression was performed to separately examine the odds of abnormal ANX and DEP based on abnormal physical function while controlling for age and sex, on the entire dataset and on diagnosis subgroups.ResultsIndividuals referred to vestibular physical therapy with self-reported abnormal physical function were more likely to have abnormal ANX (OR 5.1, p < 0.001) or DEP (OR 3.10, p = 0.002). Older adults were less likely to have abnormal ANX (OR = 0.96, p = 0.002). For individuals experiencing BPPV (n = 42), those with abnormal physical function are more likely to report ANX (OR 9.9, p = 0.009). For individuals with UVH (n = 39), those with abnormal physical function were more likely to report ANX (OR 10.1, p = 0.008) or DEP (OR 9.9, p = 0.010).ConclusionSelf-reported abnormal physical function corresponds to a higher incidence of abnormal ANX and DEP for individuals referred to VPT. Individuals with benign proximal positional vertigo and unilateral vestibular hypofunction were approximately 10 times more likely to experience abnormally high ANX or DEP compared to all other primary diagnosis. Clinicians seeing patients in VPT should be screening for anxiety and depression especially for those with self-reports of impaired physical function.

BackgroundPeople with vestibular hypofunction (PwVH) often demonstrate abnormal gait and increased fall risk. An analysis of the strategies used for maintaining walking balance is lacking in PwVH.ObjectiveThe purpose of this study was to examine how PwVH use recovery strategies and maintain stability following perturbations.MethodsPwVH and healthy controls were perturbed during walking with mediolateral ground shifts while kinematic responses were recorded.ResultsAs a group, PwVH (n = 9, unilateral loss) responded similarly to healthy participants (n = 15) with changes in foot placement, ankle inversion, ankle push-off, and trunk sway. However, responses in PwVH depended on the vestibular lesion side and functional compensation as assessed by the Functional Gait Assessment (FGA). PwVH had larger changes in stability when perturbations caused body movement toward the side of the lesion and more effective trunk responses when perturbations caused body movement away from the lesion. Additionally, PwVH who performed poorly on the FGA showed worse stability and overactive ankle and trunk responses following medial perturbations.ConclusionsThese findings demonstrate kinematic differences in balance recovery in PwVH and suggest that PwVH are more susceptible to instability when falling toward the lesion.