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To investigate vestibulo ocular reflex (VOR) in MS patients without any history of optic neuritis. 26 MS patients without any previous history of optic neuritis and 13 age- matched control subjects were included in this study. Their age ranged from 22 to 50 years old. We evaluated monocular visual evoked potential (VEP), monocular and binocular best corrected static and dynamic visual acuity, near and distance phoria and VOR gain. Mean spherical equivalent (SE) was – 0.40 ± 0.93 D and – 0.04 ± 0.14 D for study and control group, respectively (P = 0.060). There was a significant difference in dynamic visual acuity (DVA) between two groups (P = 0.029). VOR gain was not significantly different in both groups through vHIT measurements (P = 0.338). Duration of MS had a mean of 78.38 ± 75.94 months (ranged from 6 to 336 months). We found no significant correlation between disease duration and VOR (Rho 0.277, P = 0.171) or DVA (Rho 0.782, P = 0.057). Our study showed that although vHIT results decreased in MS patients, there was no significant differences between two groups. [ABSTRACT FROM AUTHOR]

This work addresses an impractical and unnatural constraint that has been generally enforced in state-of-the-art electrooculography (EOG)-based gaze estimation methods, that of maintaining a stationary head pose and position. Specifically, this work proposes an EOG-based gaze angle (GA) estimation method that accommodates natural variations in the user's head pose and position. The EOG data collected under non-stationary head conditions, which was used in this work to validate the proposed method, is also being made publicly available. This work generalises a two-eye verging gaze geometrical model to cater for arbitrary head poses and positions, and also models the dynamics of the vestibulo-ocular reflex (VOR), which refers to the eye-head coordination that normally takes place during gaze shifts under unrestrained head conditions. These methods are validated by incorporating them within a published multiple-model framework for GA estimation. When applied to short EOG data segments, a horizontal and vertical GA estimation error of 1.85 ± 0.51 ° and 2.19 ± 0.62 ° , respectively, and an eye movement detection and labelling F-score close to 90% were obtained. These results are comparable to those reported previously under stationary head conditions. This work demonstrates that accurate GA estimation and eye movement detection and labelling can be achieved using EOG signals, even when the user's head is not stationary. This work eliminates the need for users to maintain a stationary head pose and position, a common constraint in the field, thus introducing an EOG-based GA estimation method that allows users to move their heads naturally. • Real-time-implementable algorithm for EOG-based gaze estimation. • Modelling of the Vestibulo Ocular Reflex. • Multiple-model framework including models for fixations, saccades, blinks and VORs. • Gaze estimation while compensating for baseline drift and head movement. • Sample-by-sample labelling of EOG signals. [ABSTRACT FROM AUTHOR]

The present study aimed to analyse the impact of vestibulo-ocular reflex (VOR) gain deficit on postural control (PC) in children with sensorineural hearing loss. A retrospective study included 55 children with sensorineural hearing loss between 4 and 17 years of age. The Video Head Impulse Test (vHIT®) was used to assess semicircular canal function. PC was assessed on the Balance Quest® posturographic platform testing sensory organisation. Spatial and temporal postural parameters (area and mean speed of centre of pressure oscillation, spectral power index) in the OKN-U condition (optokinetic with unstable platform) were significantly better in children with than without VOR deficit. Posturographic exploration in the OKN-U condition can screen for semicircular canal deficit in hearing-impaired children. VOR deficit also seems to predict PC deficit. [ABSTRACT FROM AUTHOR]

The Vestibular/Ocular-Motor Screening (VOMS), an important component in acute (<72 h) sport-related concussion (SRC) assessment, is increasingly used alongside the Sport Concussion Assessment Tool (SCAT) and as part of the Military Acute Concussion Evaluation 2 (MACE2). VOMS demonstrates clinically useful diagnostic accuracy for acute SRC and improves the overall utility when added to the SCAT3. However, potential overlap among VOMS's vestibular and oculomotor items suggests the possibility of a more efficient version. VOMS and SCAT3 scores were analyzed for 3,958 preseason (47.8% female) and 496 acute-SRC (37.5% female) NCAA-DoD Concussion Assessment, Research, and Education (CARE) consortium collegiate athlete evaluations. Analyses revealed very large effect sizes (d = 2.39–2.45) and high correlations (rho = 0.95–0.99) among all VOMS items except near point of convergence distance (d = 0.79, rho ≤ 0.341). Receiver operating characteristic (ROC) curve analyses showed clinically useful discriminative utility for VOMS Total (AUC = 0.85) and the VOMS Total change score, where pretest symptoms were incorporated (AUC = 0.81). A modified VOMS (mVOMS) consisting of four items (smooth pursuits, horizontal saccades, horizontal vestibulo-ocular reflex, visual motion sensitivity) yielded identical AUCs to VOMS Total. Integer cutoff analyses suggest a score of ≥4 for VOMS Total and ≥4 for mVOMS Total optimizes concussion identification. Incorporating VOMS or mVOMS into SCAT3 (AUC = 0.79) significantly improved the combined tool's acute utility for acute concussion identification by a maximum of 4% (SCAT3+VOMS AUC = 0.84, SCAT3+mVOMS AUC = 0.83). Future versions of SCAT or MACE may want to consider incorporating a more parsimonious VOMS for the purpose of identifying acute concussion. [ABSTRACT FROM AUTHOR]