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The aim of this paper was to report the cases of 3 consecutive patients with mitogen-activated protein kinase kinase inhibitor (MEKi)-associated retinopathy with characteristic multiple serous retinal detachments (SRDs). A functional analysis of the retinal pigment epithelium was performed in 2 patients by electro-oculography (EOG). In all 3 patients, SRD lesions were observed in the posterior pole including the fovea of both eyes. Interestingly, neither obvious leakage in fluorescein/indocyanine angiography nor abnormal fundus autofluorescence was associated. SRDs and associated cystoid macular edema in one case rapidly resolved with the cessation of MEKi but recurred quickly after treatment resumption. In EOG tests, three of four eyes with multiple SRDs showed a marked decrease in the light-peak-to-dark-trough ratio (LP:DT ratio). The LP:DT ratio in EOG reflects the transepithelial potential of the retinal pigment epithelium, suggesting the involvement of disrupted tight junctions and impaired active transport of fluid/ions in MEKi-associated retinopathy. The latter may be the major cause of SRDs as we observed that fluid leakage in angiography was absent in the areas of the patients' SRDs.

Introduction: Video head impulse testing is frequently used to evaluate the vestibular function. During this test, eye movement responses are recorded with video-oculography (VOG). However, the use of VOG can sometimes be challenging, especially due to pupil detection problems (e.g., blinking, droopy eyelids, etc.). Therefore, this study investigated whether electro-oculography (EOG), a technique that does not depend on pupil tracking but on the orientation of the corneoretinal potential, might be an alternative to VOG for quantifying eye movement responses during head impulse testing. Subjects and methods: Head impulse testing was performed in 19 healthy subjects without a prior history of vestibular symptoms. Horizontal eye movements were recorded simultaneously with EOG (using an EOG system) and VOG (using a VHIT system: ICS Impulse). The eye movement responses to each side of both techniques were compared using a concordance correlation coeficient (rc), t-testing, and Bayes Factor (BF) paired t-testing. Results: EOG and VOG obtained eye movement traces that correlated well with each other during head impulse testing (average rc = 0.89). Average VOR gains obtained with EOG and VOG were not significantly different from each other for all subjects during left head impulses. However, VOG gains differed between both techniques regarding right head impulses. VOG showed significant VOR gain asymmetry (5% to the right), whereas EOG showed no significant asymmetry (1% to the right). Conclusion: This study demonstrated the use of EOG to record eye movements during head impulse testing for the first time. EOG and VOG obtained eye movement traces that correlated well with each other during horizontal head impulse testing. In addition, EOG showed smaller VOR gain asymmetry in healthy individuals, in contrast to VOG. These findings indicate that EOGmight potentially be applicable as an alternative to VOG for collecting eye movement responses during head impulse testing. [ABSTRACT FROM AUTHOR]

IntroductionVideo head impulse testing is frequently used to evaluate the vestibular function. During this test, eye movement responses are recorded with video-oculography (VOG). However, the use of VOG can sometimes be challenging, especially due to pupil detection problems (e.g., blinking, droopy eyelids, etc.). Therefore, this study investigated whether electro-oculography (EOG), a technique that does not depend on pupil tracking but on the orientation of the corneoretinal potential, might be an alternative to VOG for quantifying eye movement responses during head impulse testing.Subjects and methodsHead impulse testing was performed in 19 healthy subjects without a prior history of vestibular symptoms. Horizontal eye movements were recorded simultaneously with EOG (using an EOG system) and VOG (using a VHIT system: ICS Impulse). The eye movement responses to each side of both techniques were compared using a concordance correlation coefficient (rc), t-testing, and Bayes Factor (BF) paired t-testing.ResultsEOG and VOG obtained eye movement traces that correlated well with each other during head impulse testing (average rc = 0.89). Average VOR gains obtained with EOG and VOG were not significantly different from each other for all subjects during left head impulses. However, VOG gains differed between both techniques regarding right head impulses. VOG showed significant VOR gain asymmetry (5% to the right), whereas EOG showed no significant asymmetry (1% to the right).ConclusionThis study demonstrated the use of EOG to record eye movements during head impulse testing for the first time. EOG and VOG obtained eye movement traces that correlated well with each other during horizontal head impulse testing. In addition, EOG showed smaller VOR gain asymmetry in healthy individuals, in contrast to VOG. These findings indicate that EOG might potentially be applicable as an alternative to VOG for collecting eye movement responses during head impulse testing.Trial registration number10192021-38 dated 19.10.21.

The aim of this paper was to report the cases of 3 consecutive patients with mitogen-activated protein kinase kinase inhibitor (MEKi)-associated retinopathy with characteristic multiple serous retinal detachments (SRDs). A functional analysis of the retinal pigment epithelium was performed in 2 patients by electro-oculography (EOG). In all 3 patients, SRD lesions were observed in the posterior pole including the fovea of both eyes. Interestingly, neither obvious leakage in fluorescein/indocyanine angiography nor abnormal fundus autofluorescence was associated. SRDs and associated cystoid macular edema in one case rapidly resolved with the cessation of MEKi but recurred quickly after treatment resumption. In EOG tests, three of four eyes with multiple SRDs showed a marked decrease in the light-peak-to-dark-trough ratio (LP:DT ratio). The LP:DT ratio in EOG reflects the transepithelial potential of the retinal pigment epithelium, suggesting the involvement of disrupted tight junctions and impaired active transport of fluid/ions in MEKi-associated retinopathy. The latter may be the major cause of SRDs as we observed that fluid leakage in angiography was absent in the areas of the patients' SRDs. [ABSTRACT FROM AUTHOR]

An 11-year-old girl noted gradual visual loss in the right eye for 1 year with subfoveal yellow deposits in both eyes. Optical coherence tomography, electro-oculogram and electroretinogram was in-keeping with Best Disease. This disorder is discussed. [ABSTRACT FROM AUTHOR]

Abstract Objective Effect of bilateral, optic neuropathy on the function of retinal pigment epithelium has not been investigated extensively to date. This study aimed to determine the effect of bilateral, optic neuropathy on light peak:dark trough ratio, light peak and dark trough values of electro-oculography. Thirty-seven patients with a clinical diagnosis of bilateral optic neuropathy and 40 control subjects were recruited in this observational, cross-sectional study, carried out at the Neurophysiology unit, Teaching Hospital, Peradeniya, Sri Lanka. Pattern reversal visual evoked potentials, pattern electroretinography and electro-oculography were recorded in all of them. Results Twenty-four patients (64.9%) had reduced light peak:dark trough ratio values. The median light peak:dark trough ratio ± inter quartile range of the patient group (1.50 ± 0.4) was significantly lower than that of the controls (1.80 ± 0.2), (p

Background: Detection of functional impairment of vision in pre-clinical stages helps early identification of diabetic retinopathy. We aimed to determine the functional integrity of retina and post retinal pathways using electro-oculography (EOG), pattern electroretinography (PERG) and pattern-reversal visual evoked potentials (PR-VEP) in newly diagnosed diabetic patients who have not developed fundoscopic features of diabetic retinopathy. Methods: Twenty-five adults with newly diagnosed diabetes mellitus without fundoscopic evidence of retinopathy and a control group of healthy adults were subjected to visual electrophysiological assessment. Retinal pigment epithelium (RPE)-photoreceptor interaction, photoreceptors and ganglion cells of the macula and post retinal pathways were assessed by EOG, PERG and PR-VEP, respectively. Results: Fourteen of the 25 diabetic patients, i.e. 56% (95% confidence intervals 34.9%, 75.6%), had LP:DT (light peak to dark trough) ratio less than 1.7, to the cut-off defined by the International Society for Clinical Electrophysiology of Vision (ISCEV). All control group subjects had LP:DT ratios above 1.7. The median LP:DT ratio in diabetic group (1.62 ± IQR 0.27) was significantly lower than that of the controls (1.8 ± IQR 0.21). Four patients had prolonged PR-VEP P100 latencies, and seven had prolonged PERG P50 latencies as per the ISCEV cut-offs, whereas none of the control group had abnormal PERG or PR-VEP measures. Conclusion: With a limited sample, we found that 56% of newly diagnosed diabetic patients with normal fundoscopy had defective RPE-photoreceptor interaction. Further studies are needed to obtain more precise point estimates of these EOG abnormalities, and to determine the conversion rates into more advanced stages of diabetic retinopathy. [ABSTRACT FROM AUTHOR]

Organophosphorus (OP) insecticide poisoning is a significant health problem in South Asian countries. Although cholinergic receptors are present at the junction between photoreceptors and the retinal pigment epithelium (RPE), human studies of the effects of OP poisoning on the visual pathways are very few. This study aims to demonstrate the pattern of changes in retina and post retinal pathways in patients with acute OP poisoning using visual electrophysiological tests. This is an observational, cross-sectional study conducted at the Neurophysiology Unit, Teaching Hospital, Peradeniya, Sri Lanka. We tested 16 patients recovered from cholinergic phase, at least 24 h after deatropinization and within 8 weeks of OP ingestion. We assessed the functional integrity of the photoreceptors and ganglion cells of the macula by pattern electroretinography (PERG); RPE by electro-oculography (EOG); and post retinal pathways by pattern reversal visual evoked potentials (PR-VEP). Latencies and amplitudes of PR-VEP and PERG, light peak (LP), dark trough (DT) and Arden ratio of EOG were determined in patients and compared with 16 controls using the Mann–Whitney U test. Of the 16 OP-poisoned patients (median age of 37 ± IQR 20 years), six (37.5%) had reduced Arden ratio with reference to the International Society of Clinical Electrophysiology of Vision cut-off value of 1.7. The median Arden ratio in patients (1.69 ± IQR 0.36) was significantly lower compared to controls (1.90 ± IQR 0.4). The median latencies and amplitudes of PR-VEP or PERG were not significantly different between patients and controls. However, three patients had prolonged P100 latencies in PR-VEP and one had prolonged P50 latency in PERG. Acute OP poisoning seems to affect the functions of the RPE and the visual electrophysiological changes outlast the cholinergic phase. Limited evidence suggests that photoreceptors of the macula region and post retinal pathway might be affected in some patients. [ABSTRACT FROM AUTHOR]

The pressing demand for workload along with social media interaction leads to diminished alertness during work hours. Researchers attempted to measure alertness level from various cues like EEG, EOG, video-based eye movement analysis, etc. Among these, video-based eyelid and iris motion tracking gained much attention in recent years. However, most of these implementations are tested on video data of subjects without spectacles. These videos do not pose a challenge for eye detection and tracking. In this work, the authors have designed an experiment to yield a video database of 58 human subjects wearing spectacles and are at different levels of alertness. Along with spectacles, they introduced variation in session, recording frame rate (fps), illumination, and time of the experiment. They carried out an analysis to detect the reliableness of facial and ocular features like yawning and eye-blinks in the context of alertness level detection capability. Also, they observe the influence of spectacles on ocular feature detection performance under spectacles and propose a simple preprocessing step to alleviate the specular reflection problem. Extensive experiments on real-world images demonstrate that the authors’ approach achieves desirable reflection suppression results within minimum execution time compared to the state-of-the-art.

Background: Cervical dystonia is a hyperkinetic movement disorder of unknown cause. Symptoms of cervical dystonia have been induced in animals in which the integrity of the nigro-tectal pathway is disrupted, resulting in reduced inhibition of the deep layers of the superior colliculus. This same pathway is believed to play a critical role in saccade generation, particularly visually guided, express saccades. It was hypothesized that individuals with cervical dystonia would present with a higher frequency of express saccades and more directional errors. Methods: Eight individuals with cervical dystonia and 11 age- and sex-matched control participants performed three saccadic paradigms: pro-saccade, gap, and anti-saccade (120 trials per task). Eye movements were recorded using electro-oculography. Results: Mean saccadic reaction times were slower in the cervical dystonia group (only statistically significant in the anti-saccade task, F(1, 35) 5 4.76, p 5 0.036); participants with cervical dystonia produced fewer directional errors (mean 14% vs. 22%) in the anti-saccade task; and had similar frequencies of express saccades in the gap task relative to our control population (chi-square 5 1.13, p 5 0.287). All cervical dystonia participants had lower frequencies of express saccades ipsilateral to their dystonic side (the side to which their head turns), (chi-square 5 3.57, p 5 0.059). Discussion: The finding of slower saccadic reaction times in cervical dystonia does not support the concept of reduced inhibition in the nigro-tectal pathway. Further research is required to confirm the observed relationship between the lateralization of lower frequencies of express saccades and direction of head rotation in cervical dystonia.

The pressing demand for workload along with social media interaction leads to diminished alertness during work hours. Researchers attempted to measure alertness level from various cues like EEG, EOG, video‐based eye movement analysis, etc. Among these, video‐based eyelid and iris motion tracking gained much attention in recent years. However, most of these implementations are tested on video data of subjects without spectacles. These videos do not pose a challenge for eye detection and tracking. In this work, the authors have designed an experiment to yield a video database of 58 human subjects wearing spectacles and are at different levels of alertness. Along with spectacles, they introduced variation in session, recording frame rate (fps), illumination, and time of the experiment. They carried out an analysis to detect the reliableness of facial and ocular features like yawning and eye‐blinks in the context of alertness level detection capability. Also, they observe the influence of spectacles on ocular feature detection performance under spectacles and propose a simple preprocessing step to alleviate the specular reflection problem. Extensive experiments on real‐world images demonstrate that the authors' approach achieves desirable reflection suppression results within minimum execution time compared to the state‐of‐the‐art. [ABSTRACT FROM AUTHOR]

The human eye movement tracking is possible with the assistance of the electrooculography (EOG) signals. The human eye tracking system allows researchers to analyse the participant's eye movements during certain activities. This study offers the EOG signals to control the human–computer interface systems with the help of Empirical Mean Curve Decomposition (EMCD) decomposition model. At first, the input EOG signal is provided as input to the EMCD decomposition model, later the resultant signal is given to principal component analysis for dimensional reduction, and then the dimensional reduced signal is offered to multi‐wavelet decomposition model. The resultant dimensionally reduced multi‐wavelet decomposed signal is passed to the proposed Feature Mapping (FM) model, using the k‐means clustering model. Then, the Grey Wolf Optimization (GWO) algorithm is utilised to tune the margin. Next to mapping, the obtained features are provided to the nearest neighbour classifier, to obtain the eye movement. Next to the implementation, the proposed method is compared with the existing methods, and it is witnessed that the proposed methodology gives the superior performance in correspondence with accuracy, sensitivity, specificity, precision, false positive rate, false negative rate, negative predictive value, false discovery rate, F1 score and Mathews correlation coefficient. [ABSTRACT FROM AUTHOR]

Objective: Effect of bilateral, optic neuropathy on the function of retinal pigment epithelium has not been investigated extensively to date. This study aimed to determine the effect of bilateral, optic neuropathy on light peak:dark trough ratio, light peak and dark trough values of electro-oculography. Thirty-seven patients with a clinical diagnosis of bilateral optic neuropathy and 40 control subjects were recruited in this observational, cross-sectional study, carried out at the Neurophysiology unit, Teaching Hospital, Peradeniya, Sri Lanka. Pattern reversal visual evoked potentials, pattern electroretinography and electro-oculography were recorded in all of them. Results: Twenty-four patients (64.9%) had reduced light peak:dark trough ratio values. The median light peak:dark trough ratio±inter quartile range of the patient group (1.50±0.4) was significantly lower than that of the controls (1.80±0.2), (p<0.001). Median dark trough value was significantly higher in patients compared to the control value. These changes may be due to higher conductance of ion channels in the retinal pigment epithelium, sub retinal space creation, changes in choroidal circulation or secondary to photoreceptor abnormalities in the macular region. These results indicate that retinal pigment epithelium might be affected in bilateral optic neuropathy. [ABSTRACT FROM AUTHOR]

In this article, the design and development aspects of a compact bio‐potential measuring system, named ExGSense, is presented. Two versions of the prototype have been developed; first one can measure 3 + 1 V leads in time‐multiplexed fashion, while the other can measure 3 + 1 V leads simultaneously. This article also presents an efficient algorithm for filtering electrocardiogram signals which is required to attenuate the effect of motion artefacts which are inevitable in wearable systems. Further, a user‐friendly interface for PC and smartphone has also been developed. By the virtue of an ultra‐low noise instrumentation amplifier and the programmability of gain and bandwidth of the bio‐signal measuring system, a number of other bio‐potential signals like EMG, EOG and EEG have been successfully recorded using disposable, off‐the‐shelf wet Ag/AgCl electrodes. [ABSTRACT FROM AUTHOR]

Gaze or eye movements are used as a communication interface in daily life. Herein, we developed a simple method for gaze estimations based on planar approximations of voltage ratios calculated from multiple electro-oculogram signals not affected by drift phenomena, which decrease accuracy. Subsequently, we conducted simulations using an eyeball battery model and investigated the effects of adjusting electrode arrangements, determination coefficients for planar approximations of voltage ratios, and threshold values for angles between simultaneous linear equations, to improve the estimation accuracy and decreased the number of required electrodes. Numerical experiments were used to identify arrangements of six electrodes with errors that were approximately 5° less than those of nine-electrode L-shaped arrangements, indicating improved estimation accuracy with fewer electrodes. [ABSTRACT FROM AUTHOR]

Purpose: This paper studies the feasibility of frontal positioning of electrode to detect electroencephalographic signals. Methods: The experiments were conducted using a board with light-emitting diodes (LEDs) designed to stimulate SSVEP and FVEP. The flashing frequencies were conducted at 15, 23, and 31 Hz. We used the Quick Amp brain wave amplifier to collect brain wave signals at a sampling rate of 1 kHz using a frequency filter band of 10-100 Hz. Results: We found that the energy power of VEP will gradually increase from Oz position to Fp2 position. We analyze the data, proving that the Fp2 position can also be used to collect VEP data. Conclusions: Traditional measurements at the Oz location are limited because of the interference from human hair, and an additional electrode is required to detect eye movement and filter this electro-oculogram signal. Our proposed method can effectively acquire critical visually evoked potential and electro-oculogram signals without the electrode at the Oz location, which require extensive preparation of removing hair strands. We also reduced the number of electrodes used in receiving electroencephalographic signals. The frontal electrode positioning could be a remarkable breakthrough to design brain computer interface. [ABSTRACT FROM AUTHOR]

Li-Chun Hsieh,1,2 Hung-Ching Lin,2,3 Guo-She Lee4,5 1Institute of Brain Science, School of Medicine, National Yang-Ming University, Taipei, Taiwan; 2Department of Otolaryngology, Mackay Memorial Hospital, Taipei, Taiwan; 3Department of Audiology and Speech Language Pathology, Mackay Memorial Medical College, Taipei, Taiwan; 4Faculty of Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan; 5Department of Otolaryngology, Taipei City Hospital, Ren-Ai Branch, Taipei, Taiwan Background: Imbalance from degeneration of vestibular end organs is a common problem in the elderly. However, the decline of vestibular function with aging was revealed in few vestibular function tests such as vestibular autorotation test (VAT). In the current VAT, there are drawbacks of poor test–retest reliability, slippage of the sensor at high-speed rotations, and limited data about the effect of aging. We developed a correlational-VAT (cVAT) system that included a small, light sensor (less than 20 g) with wireless data transmission technique to evaluate the aging of vestibular function. Material and methods: We enrolled 53 healthy participants aged between 25 and 75 years and divided them into five age groups. The test conditions were vertical and horizontal head autorotations of frequencies from 0 to 3 Hz with closed eyes or open eyes. The cross-correlation coefficient (CCC) between eye velocity and head velocity was obtained for the head autorotations between 1 Hz and 3 Hz. The mean of the CCCs was used to represent the vestibular function. Results: Age was significantly and negatively correlated with the mean CCC for all test conditions, including horizontal or vertical autorotations with open eyes or closed eyes (P

This study proposes a novel method for sleep disorder monitoring based on a finite‐state machine (FSM) from various bio‐signals, namely electroencephalography (EEG), electro‐oculography (EOG) and electromyography (EMG) signals. The sleep signals have been obtained from physionet sleep repository, which includes horizontal EOG, submental‐EMG and EEG sampled at 100 Hz sampling frequency. Inputs given to the FSM‐based module are the processed signals from EMG, EEG and EOG signals. The FSM module for sleep analysis is composed of different states and the conditions to flow from one state to another state. In this study, two FSM modules are designed, one for sleep wave and another for sleep stage identification. Based on the outputs obtained from the above two FSM modules, the sleep disorder can be monitored. The accuracy of the proposed method has been calculated with percentage accuracy, false acceptance rate and false rejection ratio. The average classification accuracy of the finite‐state automaton (FSA)‐based method is up to 99% for all the tested fault cases. The proposed FSA method suggests a novel method and can be put to effective use in the rural areas for primary analysis. [ABSTRACT FROM AUTHOR]

The traditional signal processing algorithms suffer from large execution delay for real time issues, therefore implementation of high speed algorithms is needed. The present work aims to implement multiplier less Savitzky Golay smoothing filter (SGSF) based on distributed arithmetic (DA) for pre-processing of Electro-oculographic (EOG) signals such that speed is increased along with reduction in chip area. The filter used should be efficient enough to remove the artifacts along with least deformation from the actual signal. Savitzky-Golay (SG) filter is widely employed in biomedical signal analysis but its fast and efficient implementation is not proposed yet for EOG analysis. SGSF is selected so that disease diagnosis using saccade detection of EOG signal can be done accurately. The efficiency of proposed filter is tested in terms of signal-to-signal-plus-noise ratio (SSNR) and real time computations. It is observed from the analysis that DA based architecture increases the processing speed, reduces the chip area and original features of filtered signal are preserved. [ABSTRACT FROM AUTHOR]

Here, we report the case of a patient who presented with angle closure glaucoma and was diagnosed as ARB on fundoscopy and subsequent investigations. Keywords: Angle-closure glaucoma; autosomal recessive bestrophinopathy; electro-oculography EN Angle-closure glaucoma autosomal recessive bestrophinopathy electro-oculography 2657 2658 2 07/15/22 20220701 NES 220701 Mutations in the BEST1 gene have been associated with different ocular phenotypes. [Extracted from the article]

We present a computationally light real-time algorithm which automatically detects blinks, saccades, and fixations from electro-oculography (EOG) data and calculates their temporal parameters. The method is probabilistic which allows to consider the uncertainties in the detected events. The method is real-time in the sense that it processes the data sample-by-sample, without a need to process the whole data as a batch. Prior to the actual measurements, a short, unsupervised training period is required. The parameters of the Gaussian likelihoods are learnt using an expectation maximization algorithm. The results show the promise of the method in detecting blinks, saccades, and fixations, with detection rates close to 100 %. The presented method is published as an open source tool.

When a single light cue is given in the visual field, our eyes orient towards it with an average latency of 200 ms. If a second cue is presented at or around the time of the response to the first, a secondary eye movement occurs that represents a reorientation to the new target. While studies have shown that eye movement latencies to 'single-step' targets may or may not be lengthened with age, secondary eye movements (during 'double-step' displacements) are significantly delayed with increasing age. The aim of this study was to investigate whether the postural challenge posed simply by standing (as opposed to sitting) results in significantly longer eye movement latencies in older adults compared to the young. Ten young (<35 years) and 10 older healthy adults (>65 years) participated in the study. They were required to fixate upon a central target and move their eyes in response to 2 types of stimuli: (1) a single-step perturbation of target position either 15° to the right or left and (2) a double-step target displacement incorporating an initial target jump to the right or left by 15°, followed after 200 ms, by a shift of target position to the opposite side (e.g. +15° then −15°). All target displacement conditions were executed in sit and stand positions with the participant at the same distance from the targets. Eye movements were recorded using electro-oculography. Older adults did not show significantly longer eye movement latencies than the younger adults for single-step target displacements, and postural configuration (stand compared to sit) had no effect upon latencies for either group. We categorised double-step trials into those during which the second light changed after or before the onset of the eye shift to the first light. For the former category, young participants showed faster secondary eye shifts to the second light in the standing position, while the older adults did not. For the latter category of double-step trial, young participants showed no significant difference between sit and stand secondary eye movement latencies, but older adults were significantly longer standing compared to sitting. The older adults were significantly longer than the younger adults across both postural conditions, regardless of when the second light change occurred during the eye shift to the first light. We suggest that older adults require greater time and perhaps attentional processes to execute eye movements to unexpected changes in target position when faced with the need to maintain standing balance. [ABSTRACT FROM AUTHOR]

Study Objectives: Eye movement quantification in polysomnograms (PSG) is difficult and resource intensive. Automated eye movement detection would enable further study of eye movement patterns in normal and abnormal sleep, which could be clinically diagnostic of neurologic disorders, or used to monitor potential treatments. We trained a long short-term memory (LSTM) algorithm that can identify eye movement occurrence with high sensitivity and specificity., Methods: We conducted a retrospective, single-center study using one-hour PSG samples from 47 patients 18-90 years of age. Team members manually identified and trained an LSTM algorithm to detect eye movement presence, direction, and speed. We performed a 5-fold cross validation and implemented a "fuzzy" evaluation method to account for misclassification in the preceding and subsequent 1-second of gold standard manually labeled eye movements. We assessed G-means, discrimination, sensitivity, and specificity., Results: Overall, eye movements occurred in 9.4% of the analyzed EOG recording time from 47 patients. Eye movements were present 3.2% of N2 (lighter stages of sleep) time, 2.9% of N3 (deep sleep), and 19.8% of REM sleep. Our LSTM model had average sensitivity of 0.88 and specificity of 0.89 in 5-fold cross validation, which improved to 0.93 and 0.92 respectively using the fuzzy evaluation scheme., Conclusion: An automated algorithm can detect eye movements from EOG with excellent sensitivity and specificity. Noninvasive, automated eye movement detection has several potential clinical implications in improving sleep study stage classification and establishing normal eye movement distributions in healthy and unhealthy sleep, and in patients with and without brain injury., (© The Author(s) 2022. Published by Oxford University Press on behalf of Sleep Research Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Conclusion: The correlational vestibular autorotation test (VAT) system has the advantages of good test-retest reliability and calibrations of absolute degrees of eye movement are unnecessary when acquiring a cross correlation coefficient (CCC). The approach is able to efficiently detect peripheral vestibulopathies. Objective: A VAT has some drawbacks including poor test-retest reliability and slippage of sensor. This study aimed to develop a correlational VAT system and to evaluate the reliability and applicability of this system. Methods: Twenty healthy participants and 10 vertiginous patients were enrolled. Vertical and horizontal autorotations from 0 to 3 Hz with either closed or open eyes were performed. A small sensor and a wireless transmission technique were used to acquire the electro-ocular graph and head velocity signals. The two signals were analyzed using CCCs to assess the functioning of the vestibular ocular reflex (VOR). Results: The results showed a significantly greater CCC for open-eye versus closed-eye of head autorotations. The CCCs also increased significantly with head rotational frequencies. Moreover, the CCCs significantly correlated with the VOR gains at autorotation frequencies ≥1.0 Hz. The test-retest reliability was good (intraclass correlation coefficients ≥0.85). The vertiginous participants had significantly lower individual CCCs and overall average CCC than age- and-gender matched controls. [ABSTRACT FROM AUTHOR]

Purpose: Abnormalities in the BEST1 gene have recently been recognised as causing autosomal recessive bestrophinopathy (ARB). ARB has been noted to have a variable phenotypic presentation, distinct from that of autosomal dominant Best vitelliform macular dystrophy (BVMD). Both conditions are associated with deposits in the retina, a reduced or absent electro-oculography (EOG) light rise, and the risk of developing angle-closure glaucoma. Herein, we describe the clinical and genetic characteristics of a young male diagnosed with ARB associated with angle-closure glaucoma resulting from a novel homozygous mutation in BEST1. Methods: All research involved in this case adhered to the tenets of the Declaration of Helsinki. The proband underwent slitlamp examination, retinal autofluorescence imaging and optical coherence tomography after presenting with deteriorating vision. The findings prompted genetic testing with bi-directional DNA sequencing of coding and flanking intronic regions of BEST1. The proband's family members were subsequently screened. Results: A provisional diagnosis of ARB was made based on the findings of subretinal and schitic lesions on fundoscopy and retinal imaging, together with abnormal EOG and electroretinography. Genetic testing identified a novel homozygous mutation in BEST1, c.636+1 G>A. Family members were found to carry one copy of the mutation and had no clinical or electrophysiological evidence of disease. The proband was additionally diagnosed with angle-closure glaucoma requiring topical therapy, peripheral iridotomies and phacoemulsification. Conclusions: Phenotypic overlap, reduced penetrance, variable expressivity and the ongoing discovery of new forms of bestrophinopathies add to the difficulty in distinguishing these retinal diseases. All patients diagnosed with ARB or BVMD should be examined for narrow angles and glaucoma, given their frequent association with these conditions. [ABSTRACT FROM AUTHOR]

Electrophysiological techniques allow clinical investigations to include a 'dissection' of the visual system. Using suitable electrophysiological techniques, the 'dissection' allows function to be ascribed to the different photoreceptors (rod and cone photoreceptors), retinal layers, retinal location or the visual pathway up to the visual cortex. Combined with advances in genetics, retinal biochemistry, visual fields and ocular imaging, it is now possible to obtain a better understanding of diseases affecting the retina and visual pathways. This paper reviews core electrophysiological principles that can complement other examination techniques, including advanced ocular imaging, and help the interpretation of other clinical data and thus, refine and guide clinical diagnosis. [ABSTRACT FROM AUTHOR]

Abstract: Anomalies in the oculomotor system are well known symptoms in different neurodegenerative diseases. It has been found that patients suffering from severe spino cerebellar ataxia type 2 show deterioration in the main parameters used to describe saccadic movements, specifically the slowing of horizontal saccadic eye movements. Besides, a combination of two components, named pulse and step, constitutes an accepted model of the saccadic generation system. In the present work, independent component analysis is applied in order to separate both pulse and step components, revealing significant differences in several parameters related to the morphology of these components between patients and control responses. Ten electro-oculographic records of spino cerebellar ataxia type 2 patients and ten control subjects were processed with the proposed algorithm with the aim of obtaining a correct diagnosis. The results obtained from these real experiments reveal the validity of the proposed approach as a classification tool for the diagnosis of this disease. [Copyright &y& Elsevier]

Because of frequent involvement of the cerebellum and brainstem, ocular motor abnormalities are key features of spinocerebellar ataxias and may aid in differential diagnosis. Our objective for this study was to distinguish the subtypes by ophthalmologic features after head-shaking and positional maneuvers, which are not yet recognized as differential diagnostic tools in most common forms of spinocerebellar ataxias. Of the 302 patients with a diagnosis of cerebellar ataxia in 3 Korean University Hospitals from June 2011 to June 2012, 48 patients with spinocerebellar ataxia types 1, 2, 3, 6, 7, or 8 or with undetermined spinocerebellar ataxias were enrolled. All patients underwent a video-oculographic recording of fixation abnormalities, gaze-evoked nystagmus, positional and head-shaking nystagmus, and dysmetric saccades. Logistic regression analysis controlling for disease duration revealed that spontaneous and positional downbeat nystagmus and perverted head-shaking nystagmus were strong predictors for spinocerebellar ataxia 6, whereas saccadic intrusions and oscillations were identified as positive indicators of spinocerebellar ataxia 3. In contrast, the presence of gaze-evoked nystagmus and dysmetric saccades was a negative predictor of spinocerebellar ataxia 2. Positional maneuvers and horizontal head shaking occasionally induced or augmented saccadic intrusions/oscillations in patients with spinocerebellar ataxia types 1, 2, and 3 and undetermined spinocerebellar ataxia. The results indicated that perverted head-shaking nystagmus may be the most sensitive parameter for SCA6, whereas saccadic intrusions/oscillations are the most sensitive for spinocerebellar ataxia 3. In contrast, a paucity of gaze-evoked nystagmus and dysmetric saccades is more indicative of spinocerebellar ataxia 2. Head-shaking and positional maneuvers aid in defining ocular motor characteristics in spinocerebellar ataxias. © 2013 Movement Disorder Society [ABSTRACT FROM AUTHOR]

In recent years, an increasing number of people suffer from sleep disorders. Polysomnography (PSG) is commonly used in hospitals or sleep centers to diagnose sleep disorders because it continuously and simultaneously records multiple physiological signals during sleep. However, the excessive number of wired connections for conventional PSG is often a problem that leads to sleep disturbance. Due to the high cost and bulky body, traditional PSG systems are not suitable for sleep recording at home. This paper proposes the design and implementation of a modularized and distributed PSG system that is more convenient and has potential for recording at home. It is composed of multiple, tiny, low-cost, and wireless-synchronized signal acquisition nodes, and each node acquires specific physiological signals within a small body region to reduce sleep disturbance as a result of recording wires. To evaluate accuracy, the system and a commercial PSG system were mounted on subjects to simultaneously perform overnight recording, and the recorded data were compared. A two-phase sleep experiment was also performed to compare the comfortableness of these two systems. The results show that, in addition to high consistency (>; 93%) with the reference system, due to the reduction of the disturbance from recording wires, the proposed system has better comfortableness performance in terms of several objective and subjective sleep indices. [ABSTRACT FROM PUBLISHER]

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PurposeTo describe the spectrum of phenotypic characteristics of BEST1-related autosomal dominant vitreoretinochoroidopathy (ADVIRC) in a family with p.V86M mutation.MethodsA retrospective review of the clinical, psychophysical, and electrophysiological phenotypes of six subjects with ADVIRC. Five family members were sequenced for mutations in the BEST1gene.ResultsA heterozygous change, p.V86M (c.256G>A), was identified in the BEST1gene in the three affected subjects tested, and was shown to segregate with the disease phenotype. The distance visual acuity ranged from 20/25 to absent perception of light. Clinical features observed included angle closure glaucoma (n=2), microcornea with shallow anterior chamber (n=1), iris dysgenesis (n=2), cataracts (n=4), classical peripheral concentric band of retinal hyperpigmentation (n=5), and optic nerve dysplasia (n=1). Full-field electroretinogram response amplitudes ranged from low normal (two cases; 27 and 32 years) to non-recordable (two cases; 42 and 63 years). Goldmann fields were normal in two (27 and 28 years) but were abnormal in two older subjects. Optical coherence tomography showed macular thinning in the proband, whereas his affected daughter had normal macular thickness. Electro-oculography showed borderline Arden's ratio (1.50) in the lone case tested (27 years).ConclusionADVIRC is a slowly progressive vitreoretinal degeneration that demonstrates marked intra-familial phenotypic variability. Optic nerve dysplasia and iris dysgenesis are novel observations that extend the ocular phenotype of ADVIRC. [ABSTRACT FROM AUTHOR]

Abstract: The analysis of eye movements has proven to be valuable in both clinical work and research as well as in other fields besides medicine. The detection of saccadic eye movements and the extraction of related saccade parameters, such as maximum angular velocity, amplitude, and duration, are usually performed during the analysis of electro-oculographic (EOG) signals. This article considers a saccade detection method that is based on the constant false alarm rate technique, in which the detection sensitivity is continuously adjusted on the basis of the observed signal in order to keep the number of false alarms constant. The method is computationally efficient, it can operate autonomously without user intervention, and it is capable of detecting saccades in a sequential fashion. Therefore, the method finds potential use in applications that require automated analysis of electro-oculographic signals. Because of the constant false alarm rate property, the method can also perform in situations where ideal measurement conditions cannot be guaranteed and noise presents a considerable problem. [Copyright &y& Elsevier]

Simple diagnostic or therapeutic procedures can produce tremendous benefits for dizzy patients. To see how new ideas in the laboratory evolve into benefits for patients, an attempt to analyze how the corresponding information is distributed was made. To quantify that flow of information, a number of new scientific publications, citation numbers, and a number of new books on relevant subjects were looked at. For vertigo, this approach was facilitated by the fact that the diagnostic procedures for benign paroxysmal positioning vertigo (BPPV) and for canal paresis can be traced back to seminal publications. Results indicate that the current way of disseminating new information used here is working well, and that new ideas on diagnosis and treatment are readily available to practitioners. However, the application of new methods is limited by the availability of the required technology. It is conjectured that the technological requirements have become more complex over time, leading to a slower uptake of new technology. [ABSTRACT FROM AUTHOR]

It has been suggested that motor imagery possesses a range of useful applications in sport as well as in rehabilitation. Until now, research in this field has been hampered by the lack of an objective method to monitor the subjects’ participation in the task. In this present study, a new approach to quantifying motor imagery of goal-directed hand movements by means of eye movement registration is examined. Eye movements of 15 right-handed subjects were recorded using EOG during both physical execution and visual motor imagery of a cyclical aiming task, performed at three different inter-target distances. We found that 89% of subjects made task-related eye movements during imagery with the eyes open and 84% of participants also did so during imagery with the eyes closed. Both the number and amplitude of the eye movements during imagery closely resembled those of eye movements made during physical execution of the task. This indicates that the coupling between neural patterns for eye and hand movements remains intact when hand movements are merely imagined as opposed to being physically executed. Therefore, eye movement recordings may be used as an objective technique to evaluate subjects’ compliance, motor imagery ability, and spatial accuracy. [Copyright &y& Elsevier]