Journal of Vestibular Research-Equilibrium & Orientation最新文献

Objective: The purpose of this study was to determine the extent to which sensory integration strategies via head sway, derived from a Head-Mounted Display (HMD), change in people with vestibular disorders following vestibular rehabilitation.

Design: Randomized Controlled TrialSetting:Vestibular Rehabilitation ClinicParticipants:Thirty participants with vestibular dysfunction and 21 age-matched controls.

Main outcome measures: Participants experienced two levels of visual surround (static or moving 'stars', front to back at 0.2 Hz, 32 mm) and white noise (none or rhythmic) while their head sway was recorded via the HTC Vive. We quantified head sway via Directional Path (DP) and Root Mean Square Velocity (RMSV) in 5 directions: anterior-posterior, medio-lateral, pitch, yaw, and roll and Power Spectral Density in low (PSD 1), medium (PSD 2) and high (PSD 3) frequencies in the anterior-posterior direction.

Interventions: Participants performed the assessment prior to being randomized into 8-weeks of contextual sensory integration training in virtual reality or traditional vestibular rehabilitation and once again following completion of the intervention. Controls performed the assessment once. Twelve participants dropped out, half due to covid lock-down. We applied an intention to treat analysis.

Results: We observed significant increases in AP DP, RMSV and all PSDs with change in visual level. Both intervention groups significantly decreased medio-lateral, pitch and roll DP and RMSV and anterior-posterior PSD 2 with no group differences. Vestibular participants were significantly higher than controls on all outcomes pre rehabilitation. Post rehabilitation they were only significantly higher on PSD 2. Sound was not a significant predictor of head sway in this protocol.

Conclusions: Head sway decreased following vestibular rehabilitation regardless of visual load or type of intervention applied. This change was measured via head kinematics derived from a portable HMD which can serve as a sensitive in-clinic assessment for tracking improvement over time.

Background: Diagnostic criteria of vestibular migraine (VM) by the Bárány classification consists of complex combinations of characteristics of dizziness: episodes, intensity, duration, migraine according to International Classification of Headache Disorders (ICHD), and migraine features accompanying vertigo. The prevalence according to strictly applied Bárány criteria may be much lower than preliminary clincal diagnosis.

Objective: The purpose of this study is to investigate the prevalence of VM according to strictly applied Bárány criteria among dizzy patients who visited the otolaryngology department.

Methods: The medical records of patients with dizziness from December 2018 to November 2020 were retrospectively searched using a clinical big data system. The patients completed a questionnaire designed to identify VM according to Bárány classification. Microsoft Excel function formulas were used to identify cases that met the criteria.

Results: During the study period, 955 new patients visited the otolaryngology department complaining of dizziness, of which 11.6% were assessed as preliminary clinical diagnosis of VM in outpatient clinic. However, VM according to strictly applied Bárány criteria accounted for only 2.9% of dizzy patients.

Conclusion: The prevalence of VM according to strictly applied Bárány criteria could be significantly lower than that of preliminary clinical diagnosis in outpatient clinic.

Background: Cochlear implantation (CI) is associated with changes in the histopathology of the inner ear and impairment of vestibular function.

Objective: The objectives of our study were to evaluate patients for clinical manifestations of space perception and balance changes before surgery, compare them with asymptomatic subjects (controls), and report changes in posturography and subjective visual vertical (SVV) during the acute post-surgery period in patients.

Methods: Examination was performed using static posturography and the SVV measurement. We examined 46 control subjects and 39 CI patients. Patients were examined pre-surgery (Pre), 2nd day (D2) and then 14th day (D14) after implantation.

Results: Baseline SVV was not different between patients and control group. There was a statistically significant difference (p < 0.001) in SVV between subgroups of right- and left-implanted patients at D2 (-1.36±3.02° and 2.71±2.36°, right and left side implanted respectively) but not Pre (0.76±1.07° and 0.31±1.82°) or D14 (0.72±1.83° and 1.29±1.60°). Baseline posturography parameters between patients and control group were statistically significantly different during stance on foam with eyes closed (p < 0.05). There was no statistically significant difference in posturography among Pre, D2 and D14.

Conclusions: CI candidates have impaired postural control before surgery. CI surgery influences perception of subjective visual vertical in acute post-surgery period with SVV deviation contralateral to side of cochlear implantation, but not after two weeks.

Objective: We aimed to identify the proportion of each medical condition or disease contributing to dizziness and their disposition in the Emergency Department (ED).

Methods: This retrospective, descriptive study examined data from the Osaka Emergency Information Research Intelligent Operation Network system in Japan for the period from January 1, 2018 to December 31, 2020. The inclusion criteria were patients with presumptive ICD-10 codes including "dizziness" or "vertigo". Patient demographics were compared using the χ2 test and Kruskal-Wallis test. Logistic regression analysis was performed to calculate disposition from ED (emergency admission or discharge) over the 3-year study period. The adjusted odds ratio (OR) and 95% confidence interval (CI) were calculated using multivariate analyses.

Results: During the 3-year study period, a total of 1,346,457 patients (462,773 in 2018, 468,697 in 2019, and 414,987 in 2020; P < 0.001), including 53,190 patients with dizziness (18,396 in 2018, 18,649 in 2019, and 16,145 in 2020; P = 0.058), were identified as having been transported to hospitals by ambulance in Osaka Prefecture. Dizziness and giddiness (R42) was the most common form of dizziness, in 27,075 cases (9,570 in 2018, 9,613 in 2019, and 7,892 in 2020; P < 0.001; Gender composition showed 10,483 males and 16,592 females.) Vestibular Neuronitis (H81.2) showed significant increase in 2020 compared to the two preceding years (91 in 2018, 119 in 2019, and 130 in 2020, P = 0.003; including 174 males and 167 females, respectively). Of the 53,190 patients with dizziness, 11,862 (22.3%; 4,323 males, 7,539 females) were admitted to hospital. The odds ratio (OR) for emergency admission for dizziness in 2020 during the COVID-19 pandemic was 0.98 (95% confidence interval (CI), 0.93- 1.03) with reference to 2018.

Conclusion: Patients with dizziness accounted approximately 4% of ED transportations, with about 20% requiring hospital admission, irrespective of the COVID-19 pandemic. Vestibular neuronitis was significantly increased in 2020.

Background: Idiopathic scoliosis (IS) is a structural spinal deformity that can affect the position of the head. One of the etiological hypotheses is that it can be caused by dysfunction of the vestibular system, which can cause abnormal perception of subjective visual vertical (SVV).

Objective: This study aimed to evaluate the differences in head position and its possible correlation with the perception of SVV in children with IS.

Methods: We examined 37 patients with IS and 37 healthy individuals. The position of the head was evaluated from digital photographs, where we compared the coronal head tilt and the coronal shoulder angle. Measurement of SVV perception was performed using the Bucket method.

Results: Coronal head tilt values were significantly different between the groups (median 2.3° [interquartile range 1.8-4.2] vs 1.3° [0.9-2.3], p = 0.001; patients vs. controls). There was a significant difference in SVV between the groups (2.33° [1.40-3.25] vs 0.50° [0.41-1.10], p < 0.001; patients vs controls). There was a correlation between the side of head tilt and the side of SVV in patients with IS (χ2 = 5.6, p = 0.02).

Conclusions: Patients with IS had a greater head tilt in the coronal plane and impaired SVV perception.

Background: The vestibular system provides a comprehensive estimate of self-motion in 3D space. Widely used to artificially stimulate the vestibular system, binaural-bipolar square-wave Galvanic Vestibular Stimulation (GVS) elicits a virtual sensation of roll rotation. Postural responses to GVS have been clearly delineated, however quantifying the perceived virtual rotation vector has not been fully realised.

Objective: We aimed to quantify the perceived virtual roll rotation vector elicited by GVS using a psychophysical approach on a 3D turntable.

Methods: Participants were placed supine on the 3D turntable and rotated around the naso-occipital axis while supine and received square-wave binaural-bipolar GVS or sham stimulation. GVS amplitudes and intensities were systematically manipulated. The turntable motion profile consisted of a velocity step of 20°/s2 until the trial velocity between 0-20°/s was reached, followed by a 1°/s ramp until the end of the trial. In a psychophysical adaptive staircase procedure, we systematically varied the roll velocity to identify the exact velocity that cancelled the perceived roll sensation induced by GVS.

Results: Participants perceived a virtual roll rotation towards the cathode of approximately 2°/s velocity for 1 mA GVS and 6°/s velocity for 2.5 mA GVS. The observed values were stable across repetitions.

Conclusions: Our results quantify for the first time the perceived virtual roll rotations induced by binaural-bipolar square-wave GVS. Importantly, estimates were based on perceptual judgements, in the absence of motor or postural responses and in a head orientation where the GVS-induced roll sensation did not interact with the perceived direction of gravity. This is an important step towards applications of GVS in different settings, including sensory substitution or Virtual Reality.

Background/objective: There exists limited information in the literature on dominant hand preference in relation with vHIT applications. The present study aimed to examine the relationship between the clinician's dominant use of right- or left-hand and vHIT results.

Methods: A Synapsys vHIT Ulmer device was used in the study. The tests were administered by 3 clinicians experienced in vHIT, 2 of whom were right-handed and 1 left-handed. The test was applied to the 94 participants three times, one week apart.

Results: In this study, the correlation between right-handed clinicians and left-handed clinicians was examined, and in all SCCs, namely RA, LA, RL, LL, RP and LP, a moderate positive significant correlation was found between right-handed1 and right-handed2, between right-handed1 and left-handed, and between right-handed2 and left-handed.

Conclusions: In this study, these findings suggested that measures were reliable across test sessions regardless of hand dominancy (right or left). Based on the vHIT results we obtained with three different right- or left-handed clinicians, the clinician should evaluate the results according to the dominant side.