Journal of Vestibular Research-Equilibrium & Orientation最新文献

Background: The technique of measuring ocular vestibular evoked myogenic potentials (oVEMP) in response to Mini-shaker vibration is relatively new, there is a limited normative data to define the presence or absence of a response in the literature.

Objective: To determine the test-retest reliability of cervical and ocular VEMPs (cVEMP and oVEMP, respectively) to air-conducted sound (ACS) and bone-conducted vibration (BCV) stimulation and to determine normative ranges for the responses.

Methods: Twenty normal-hearing individuals (40 ears) and 20 hearing impaired volunteers with normal balance function (40 ears) were examined in this study. ACS cVEMP and BCV oVEMP (using a Mini-shaker) were recorded from both groups to assess the test-retest reliability and to collect normative VEMP data for P1/N1 latencies and amplitudes from 20 normal hearing individuals. To test reliability, VEMP recordings were repeated within the same session.

Results: The test-retest reliability for all the cVEMP parameters showed excellent reliability whereas oVEMP parameters showed between fair and excellent reliability depending on the parameter tested. Normative data for VEMP P1/N1 latencies and amplitudes were established.

Conclusions: Normative data and test-retest reliability for BCV oVEMP using the Mini-shaker at 100 Hz were established in our study for the first time in the literature. Responses appear reliable.

Background/objective: Persistent postural-perceptual dizziness (PPPD) is worsened in a standing posture, or by body movement, or visual stimulation. We aimed to evaluate postural stability in PPPD patients using foam posturography and to investigate the dependence on visual and somatosensory input in the standing posture.

Methods: Foam posturography was performed on 53 PPPD patients, and data from the PPPD patients were compared with the data from an age- and sex-matched healthy controls. The PPPD patients were divided into four groups based on the findings of vestibular function tests and the effect of vestibular function on posturographic data was examined.

Results: Romberg's ratios were significantly higher in PPPD patients than in controls. The median Romberg's ratios in PPPD patients with normal vestibular function were also higher than those in controls. However, foam ratio was significantly lower in PPPD patients than in controls. The median foam ratios in PPPD patients with vestibular dysfunction were also lower than those in controls.

Conclusions: In a standing posture, PPPD patients may be more dependent on visual input and less dependent on somatosensory input than healthy subjects. Higher dependence on visual and lower dependence on somatosensory input in PPPD may be a feature unaffected by vestibular function.

The computerized rotational head impulse test (crHIT) uses a computer-controlled rotational chair to deliver whole-body rotational impulses to assess the semicircular canals. The crHIT has only been described for horizontal head plane rotations. The purpose of this study was to describe the crHIT for vertical head plane rotations. In this preliminary study, we assessed four patients with surgically confirmed unilateral peripheral vestibular abnormalities and two control subjects. Results indicated that the crHIT was well-tolerated for both horizontal head plane and vertical head plane stimuli. The crHIT successfully assessed each of the six semicircular canals. This study suggests that the crHIT has the potential to become a new laboratory-based vestibular test for both the horizontal and vertical semicircular canals.

Background: Vestibular rehabilitation (VR) is a commonly employed treatment method for disorders of dizziness and imbalance. Access to a clinic for rehabilitation appointments can be challenging for a person experiencing dizziness. Telehealth may offer a comparable alternative to clinic-based VR for some patients.

Objective: The objective of this study was to determine the efficacy of telehealth-based VR compared to traditional clinic-based VR, as measured with the Dizziness Handicapped Inventory (DHI) in a retrospective sample of patients with vestibular conditions.

Methods: This is a retrospective, multi-institutional review from May 2020 to January 2021. Three study groups were analyzed: a telehealth group, a hybrid group, and a clinic based control group. Treatment efficacy was measured using the DHI. A repeated measures ANCOVA was performed to compare changes between the groups and across timepoints.

Results: The repeated measures ANCOVA was not significant for the interaction of groups (control, telehealth, and hybrid) by time (pre and post) (p > 0.05). However, there was a significant main effect for time (pre and post) (p < 0.05). Specifically, all groups improved DHI scores from pre to post treatment with mean differences of control: 31.85 points, telehealth: 18.75 points, and hybrid: 21.45 points.

Conclusion: Findings showed that in-clinic, telehealth, and hybrid groups demonstrated a decrease in DHI scores, indicating self-reported improvements in the impact of dizziness on daily life. Continued research is recommended to explore the efficacy of using telehealth in assessing and treating vestibular conditions.

Background: The video head impulse test (vHIT) is a common assessment of semicircular canal function during high-speed impulses. Reliability of the vHIT for assessing vertical semicircular canals is uncertain. Vertical head impulses require a complex head movement, making it difficult to isolate a single semicircular canal and interpret resulting eye rotations.

Objective: The purpose of this study was to provide descriptive head kinematics and vestibular stimuli during vertical plane impulses to ultimately improve impulse delivery and interpretation of vHIT results for vertical semicircular canals.

Methods: Six participants received right anterior (RA) and left posterior (LP) semicircular canal impulses. Linear displacements, rotational displacements, and rotational velocities of the head were measured. Peak velocities in semicircular canal planes and peak-to-peak gravitoinertial accelerations at the otolith organs were derived from head kinematics.

Results: The largest rotational velocities occurred in the target semicircular canal plane, with non-negligible velocities occurring in non-target planes. Larger vertical displacements and accelerations occurred on the right side of the head compared to the left for RA and LP impulses.

Conclusions: These results provide a foundation for designing protocols to optimize stimulation applied to a singular vertical semicircular canal and for interpreting results from the vHIT for vertical semicircular canals.

Background: The reproducibility of the effective intensity of noisy galvanic vestibular stimulation (nGVS) to improve postural stability is not well known.

Objective: We aimed to investigate inter-day and intra-day variations in effective intensity in patients with bilateral vestibulopathy (BVP).

Methods: Thirteen BVP patients were measured for center-of-pressure movements in the standing posture at five time points: morning of the first test day, morning and evening of the second test day, and morning and evening of the third test day. The mean velocity, the envelopment area, and the root mean square were measured in the eyes-closed condition for 30 s during nGVS application ranging from 0 to 1000μA. The effective intensity was defined as the intensity at which all the three parameters measured during the stimulation were simultaneously smaller than the values at baseline (0μA).

Results: Seven of the 13 patients had a common effective intensity throughout the three test days. Six patients on the second test day and five patients on the third test day had no common effective intensity between morning and evening.

Conclusions: The effective intensity of nGVS changes depending on the time during the day as well as between the days.

Background: 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.

Objective: 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.

Methods: 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.

Results: 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.

Conclusions: 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.

Background: Unilateral vestibular hypofunction (UVH) may lead to modifications on metabolism and body composition. Vestibular rehabilitation (VR) demonstrated its effectiveness in ameliorating balance function and several other daily-living aspects.

Objectives: The aim of this study was to evaluate metabolic composition, by means of bioelectrical impedance analysis (BIA) and daily activity, with the use of a wrist-worn movement tracker, in UVH participants before and after VR, and to compare data with a healthy control group (CG) of adults.

Methods: 46 UVH and 60 CG participants underwent otoneurological testing, self-report and performance questionnaires, BIA, and wore a device tracking daily movement and energy expenditure for one full day; this was performed before and after VR.

Results: UVH participants demonstrated a significant (p = 0.008) increase in muscle mass after VR, and, when compared to CG, no differences were present with respect to visceral fat and muscle mass. UVH adults reported a significant increase in energy expenditure spent in movement (p = 0.008) and during the day (p = 0.009), daily number of strides (p = 0.009) and calories spent in sweeping (p = 0.009) and stairing (p = 0.008).

Conclusions: Results from this study show that VR provided an improvement of metabolic function and body composition of people with UVH, possibly by contrasting structural modifications in neural pathways stemming from the vestibular nuclei and connected to autonomous function.