[The impact of augmented reality glasses on human visual efficiency and digital eye fatigue].

Objective: To investigate the differences in reading efficiency and visual fatigue between the use of augmented reality (AR) glasses and laptops. Methods: A prospective self-controlled study was conducted. Healthy students from Capital Medical University who frequently engaged in long-term near work and used laptops and other digital display devices were recruited as subjects at Beijing Tongren Hospital, Capital Medical University between November 1 and November 15, 2023. LogMAR visual acuity, visual functions (accommodation, convergence, and fusion), and visual fatigue scores (Likert visual fatigue scale) of the participants were assessed. The order of using the laptop and AR glasses for each participant was determined by a coin toss. Reading efficiency (reading speed and error rate multiplied by the detection rate of incorrect numbers) with different devices for 10 minutes at the same time on different dates and visual fatigue scores after watching a 20-minute video were measured. Statistical analyses were performed using paired t-tests and Wilcoxon signed-rank tests. Results: A total of 20 eligible subjects were included, comprising 7 males and 13 females, with a mean age of (25.45±2.27) years. There was no significant change in binocular visual acuity before and after using AR glasses and laptops (both P>0.05). The reading speed and reading efficiency of using AR glasses [(34.03±9.25) and (29.19±7.62) digits/min, respectively] were significantly lower than those of using laptops [(39.43±10.36) and (35.67±9.87) digits/min, respectively] (t=4.36, P<0.001), while the difference in error detection rate was not statistically significant (t=1.29, P=0.213). There was no statistically significant difference in visual fatigue scores before watching videos with the two devices (Z=-0.71, P=0.480). However, the visual fatigue score after watching videos with AR glasses [(20.55±5.04) points] was significantly higher than that with laptops [16.50 (13.00, 19.75) points] (Z=-2.85, P=0.004). The visual fatigue scores after watching videos with both devices were significantly higher than before (P<0.05), with a more significant increase observed with AR glasses [(6.05±3.50) points] (Z=-3.41, P<0.001). Conclusion: Compared with using laptops, the reading speed and efficiency were lower, and the visual fatigue was more pronounced with the use of AR glasses at the current technical level. Further optimization and improvement of AR glasses are warranted.

[Chinese expert consensus on the diagnosis and treatment of asthenopia (2024)].

Asthenopia is a group of eye discomfort syndromes with complex clinical manifestations, accompanied with systemic symptoms or not. It is caused by diverse influencing factors and occurs upon overuse of the eyes. Over the past decade, significant changes have appeared in the etiology, clinical manifestation and treatment of asthenopia with great changes in the society and lifestyles. The Chinese Optometric Association of Chinese Ophthalmological Society and the Optometry Group of Chinese Ophthalmologist Association have organized nationwide experts in the field to thoroughly discuss the latest researches on asthenopia. Consensus opinions have been formed on the causes, influencing factors, clinical manifestations, diagnosis and treatment of asthenopia, following the definition of asthenopia in the International Classification of Diseases, so as to provide guidance for the clinical diagnosis and treatment of asthenopia.

High-Frequency Discrete-Interval Binary Sequence in Asynchronous C-VEP-Based BCI for Visual Fatigue Reduction.

In code-modulated visual evoked potential (c-VEP) based BCI systems, flickering visual stimuli may result in visual fatigue. Thus, we introduced a discrete-interval binary sequence (DIBS) as visual stimulus modulation, with its power spectrum optimized to emphasize high-frequency components (40 Hz-60 Hz). 8 and 17 subjects participated, respectively, in offline and online experiments on a 4-target asynchronous c-VEP-based BCI system designed to realize a high positive predictive value (PPV), a low false positive rate (FPR) during idle states, and a high true positive rate (TPR) in control states, while minimizing visual fatigue level. Two visual stimuli modulations were introduced and compared: a maximum length sequence (m-sequence) and the high-frequency discrete-interval binary sequence (DIBS). The decoding algorithm was compared among the canonical correlation analysis (CCA), the task-related component analysis (TRCA), and two approaches of sub-band component weight calculation (the traditional method and the proportional method) for FBCCA and FBTRCA. In the online experiments, the average PPV, FPR and TPR achieved, respectively [Formula: see text], [Formula: see text], [Formula: see text] with m-sequence, while [Formula: see text], [Formula: see text] and [Formula: see text] with DIBS. Estimated by objective eye-related metrics and a subjective questionnaire, the visual fatigue in DIBS cases is significantly smaller than that in m-sequence cases. In this study, the feasibility of a novel modulation approach for visual fatigue reduction was proved in an asynchronous c-VEP system, while maintaining comparable performance to existing methods, which provides further insights towards enhancing this field's long-term viability and user-friendliness.

Visually induced symptoms questionnaire (VISQ): A subjective evaluation method for biomedical effects induced by stereoscopic 3D video.

The purpose of this paper is to establish an easy-to-use questionnaire for subjective evaluations of visually induced motion sickness (VIMS) and visual fatigue caused by stereoscopic 3D (s3D) images. We reviewed previously used questionnaires and extracted 51 important subjective evaluation items from them. We then recruited 251 participants to observe 3D images designed to easily induce sickness or visual fatigue, and we asked them to respond to the 51 items. As a result of exploratory factor analysis, four factors were extracted according to their factor loadings, and the number of items was reduced to 21. Further processing by confirmatory factor analysis led to the selection of 15 items. Comparing mean ratings for each factor before and after item reduction indicated that item reduction did not significantly affect the participant responses. Therefore, the 15-item Visually Induced Symptoms Questionnaire (VISQ), can be used to evaluate VIMS and s3D visual fatigue.

Assessment of visual fatigue in SSVEP-based brain-computer interface: a comprehensive study.

Fatigue deteriorates the performance of a brain-computer interface (BCI) system; thus, reliable detection of fatigue is the first step to counter this problem. The fatigue evaluated by means of electroencephalographic (EEG) signals has been studied in many research projects, but widely different results have been reported. Moreover, there is scant research when considering the fatigue on steady-state visually evoked potential (SSVEP)-based BCI. Therefore, nowadays, fatigue detection is not a completely solved topic. In the current work, the issues found in the literature that led to the differences in the results are identified and saved by performing a new experiment on an SSVEP-based BCI system. The experiment was long enough to produce fatigue in the users, and different SSVEP stimulation ranges were used. Additionally, the EEG features commonly reported in the literature (EEG rhythms powers, SNR, etc.) were calculated as well as newly proposed features (spectral features and Lempel-Ziv complexity). The analysis was carried out on O1, Oz and O2 channels. This work found a tendency of displacement from high-frequency rhythms to low-frequency ones, and thus, better EEG features should present a similar behaviour. Then, the 'relative power' of EEG rhythms, the rates (θ + α)/ß, α/ß and θ/ß, some spectral features (central and mean frequencies, asymmetry and kurtosis coefficients, etc.) and Lempel-Ziv complexity are proposed as reliable EEG features for fatigue detection. Hence, this set of features may be used to construct a more trustworthy fatigue index.

An enhanced model for environmental dry eye: Exploring pathological features and underlying factors.

This study aimed to develop an enhanced environmental dry eye (EDE) model that accurately reproduces the etiology of prolonged visual fatigue and investigates the underlying pathological features. A total of 40 adult SPF-grade Wistar rats were randomly assigned to control (n = 20) and model (n = 20) groups. Rats in the control group were maintained under normal conditions, while rats in the model group were exposed to a controlled frontal airflow of 2-4 m/s from a fan for 7.5 h daily while placed on a suspended cylindrical wire mesh frame. Various assessments were performed at different time points during the 14-day experiment, including blink frequency, tear secretion (phenol red thread test), tear film breakup time (BUT), fluorescein staining (FL), corneal epithelial status (light microscopy), ultrastructure of corneal epithelial cells (electron microscopy), and expression levels of inflammatory cytokines (IL-1ß, TNF-α) in tears (enzyme-linked immunosorbent assay). Additionally, mRNA and protein expression levels of MMP-9, IL1ß, IL6, TNF-α, IFN-γ, and caspase-3 in corneal tissues were quantified (real-time quantitative PCR and Western blotting). Compared to the control group, the model group rats exhibited significant decreases in blink frequency (P < 0.001), tear secretion (Schirmer I test) values (P < 0.001), and tear film breakup time levels (P < 0.001). There was also a significant increase in fluorescein staining scores (P < 0.001) in the model group. Histological examination revealed distinct differences of the corneal epithelium between groups. The corneal epithelium of the model group appeared thicker, with disorganized cell arrangement in the superficial and basal layers, partial defects or detachment of superficial epithelial cells, and a rough, uneven surface. Scanning electron microscopy observations showed a rough corneal epithelial surface with numerous cracks and scattered vesicular-like structures in the model group. Furthermore, the model group rats exhibited a significant increase in expression of IL-1ß and TNF-α in tears (P < 0.001), and upregulated expression levels of MMP-9, TNF-α, IL-1ß, caspase-3, IL-6, and IFN-γ at both the mRNA and protein levels in corneal tissues (P < 0.001). In conclusion, the modified "wire-meshing cylindrical board" model effectively overcomes the limitations of the traditional "jogging board " dry eye model and successfully simulates the etiology of prolonged visual fatigue. This innovative EDE model demonstrates a high degree of relevance to dry eye conditions resulting from prolonged visual tasks, with a high success rate of model induction. Moreover, it proves to be a simple, practical, and easily replicable model, making it highly suitable for further studies on prolonged visual fatigue and facilitating its widespread adoption in research and clinical applications.

Exploring the Effect of Trataka (A Yogic Cleansing Technique) and Cold Eye Pack on Eye Strain During COVID-19 Pandemic: A Randomized Three-Arm Trial.

Objective: Computer vision syndrome is a major global public health concern affecting >60 million individuals globally. Yoga and naturopathy practices can reduce visual fatigue and strain. The present study attempted to explore the effect of trataka that is, a yogic cleansing technique and cold eye pack on visual strain and fatigue. Subjects: Three hundred volunteers from an IT company were recruited following inclusion and exclusion criteria. Intervention: The subjects were randomly distributed in three groups, that is, trataka, cold eye pack, and waitlist control group with an allocation ratio of 1:1:1. Outcome measure: Visual Fatigue Scale and Visual symptoms checklist (VSC) was administered at baseline and end of 2 weeks. Repeated measures analysis of variance (RM-ANOVA) with Bonferroni corrections was used to test the difference across the groups. Results: All the variables were similar at the baseline among the groups. Significant changes in the within-group analysis occurred in both the trataka and cold eye pack groups. The RM-ANOVA revealed significant differences in the VAS and VSC (p = 0.001) and the post hoc analysis suggested that there were significant differences in both the trataka and cold eye pack group when compared with the control group (p = 0.001); however, there was no differences between the trataka and cold eye pack group in both the scales (p = 1). Conclusions: The results of the present study suggest that a trataka and cold eye pack for 14 days improves self-rated visual strain and fatigue among IT professionals with computer vision syndrome. Clinical Trial registration number: CTRI/2020/11/029003.

Visual display terminal syndrome and its associated factors among university students during the COVID-19 pandemic.

BACKGROUND: Ever since the start of the coronavirus disease 2019 (COVID-19) pandemic, students have been spending an increasingly longer time staring at electrical devices to take online courses. OBJECTIVE: This study aimed to investigate the effect of the virtual class environment on eye and musculoskeletal problems in university students during the COVID-19 pandemic. METHODS: A total of 365 university students were enrolled in this study. They completed an online survey to examine the effects of online learning on eye and musculoskeletal health during the COVID-19 pandemic. The questionnaires consisted of four sections: demographic and general information, environmental and work factors, device-related factors, and visual display terminal syndrome (VDTS). RESULTS: Participants have been taking online classes of 14.5 hours per week during the COVID-19 pandemic. They reported the mean daily usage of digital devices of 4.8±2.2 hours before the pandemic but this increased to 8.1±2.9 during the pandemic. Eye fatigue and neck, shoulder, and back pain have also been reported. The mean VDTS score was significantly influenced by gender, obesity, daily exercise, regular breaks, wear of blue light-blocking glasses, daily hours of electronic device use, and illumination of room. CONCLUSION: The results of this study showed that university students taking online classes suffered more from VDTS, especially in eye fatigue and neck, lower back, and shoulder pain during COVID-19 pandemic than prior. This study suggests that it is necessary to take breaks in online classes and regularly provide appropriate eye exercise and physical activity to prevent VDTS.

Prevalence of computer vision syndrome: A systematic review and meta-analysis.

PURPOSE: This review aimed to estimate the prevalence of computer vision syndrome (CVS) in the general population and subgroups. METHODS: A search was conducted in the following the databases: PubMed, SCOPUS, EMBASE, and Web of Science until February 13, 2023. We included studies that assessed the prevalence of CVS in any population. The Joanna Briggs Institute's critical appraisal tool was used to evaluate the methodological quality. A meta-analysis of the prevalence of CVS was done using a random-effects model, assessing the sources of heterogeneity using subgroup and meta-regression analyses. RESULTS: A total of 103 cross-sectional studies with 66 577 participants were included. The prevalence of CVS was 69.0% (95% CI: 62.3 to 75.3; I2: 99.7%), ranging from 12.1 to 97.3% across studies. Point prevalence was higher in women than in men (71.4 vs. 61.8%), university students (76.1%), Africa (71.2%), Asia (69.9%), contact lens wearers (73.1% vs. 63.8%) in studies conducted before the COVID-19 pandemic (72.8%), and in those that did not use the CVS-Q questionnaire (75.4%). In meta-regression, using the CVS-Q scale was associated with a lower prevalence of CVS. CONCLUSION: Seven out of ten people suffer from CVS. Preventive strategies and interventions are needed to decrease the prevalence of this condition which can affect productivity and quality of life. Future studies should standardize a definition of CVS.

Contributions of educational interventions in the management of Computer Vision Syndrome: a review of the literature / Aportes de las intervenciones educativas en el manejo del Síndrome Visual Informático: una revisión de literatura / Contribuições das intervenções educacionais no Manejo da Síndrome da Visão Computacional: uma revisão de literatura

Objective: To identify health education interventions that have demonstrated improvements in the visual and ocular health of computer-using workers with Computer Vision Syndrome. Method: Bibliographic review of original articles in Spanish and English, published between 2017 and June 2022 in PubMed, Scopus, MEDLINE (EBSCO), Redalyc, and Ovid databases. Results: Out of 1,695 articles, 11 complied with the protocol. Of these, 90.90% were published from 2020 to June 2022 and India had the highest number of publications (27.27%). Most of the studies were experimental or quasi-experimental (36.36%), and for the qualitative synthesis they were classified in educational interventions with technology 54.54% (n=6) and those that handled traditional education 45.45% (n=5). Conclusion: Health education interventions were shown to contribute to the improvement of visual and ocular health of computer users with Computer Vision Syndrome. It is necessary to investigate and divulge results about the topic, which contribute to the processes of promotion of visual and ocular health, as well as in the prevention of Computer Vision Syndrome in the workplace

Objetivo: Identificar intervenciones de educación para la salud que hayan demostrado me-joras en la salud visual y ocular de trabajadores usuarios de computadoras con Síndrome de Visión por Computador. Método: Revisión bibliográfica de artículos originales en español e inglés, publicados entre 2017 y junio de 2022 en las bases de datos PubMed, Scopus, MEDLINE (EBSCO), Redalyc y Ovid. Resultados: De 1.695 artículos, 11 cumplieron con el protocolo. De estos, el 90,90% se publicaron desde 2020 hasta junio de 2022 y la India tuvo el mayor número de publicaciones (27,27%). La mayoría de los estudios fueron experimentales o cuasi-experimentales (36,36%), y para la síntesis cualitativa se clasificaron en intervenciones educativas con tecnología 54,54% (n=6) y las que manejaban educación tradicional 45,45% (n=5). Conclusión: Se demostró que las intervenciones de educación en salud contribuyen a la mejora de la salud visual y ocular de los usuarios de computadora con Síndrome de Visión por Computador. Es necesario investigar y divulgar resultados sobre el tema, que contribuyan a los procesos de promoción de la salud visual y ocular, así como en la prevención del Síndrome de Visión por Computador en el ámbito laboral

Objetivo: Identificar intervenções de educação em saúde que demonstraram melhorias na saúde visual e ocular de trabalhadores usuários de computador com Síndrome de Visão de Computa-dor. Método: Revisão bibliográfica de artigos originais em espanhol e inglês, publicados entre 2017 e junho de 2022 nas bases de dados PubMed, Scopus, MEDLINE (EBSCO), Redalyc e Ovid. Resultados: Dos 1.695 artigos, 11 estavam de acordo com o protocolo. Destes, 90,90% foram publicados de 2020 a junho de 2022 e a Índia apresentou o maior número de publicações (27,27%). A maioria dos estudos foi experimental ou quase-experimental (36,36%), e para a síntese qualitativa foram classificados em intervenções educativas com tecnologia 54,54% (n=6) e aquelas que tratavam da educação tradicional 45,45% (n=5). Conclusão: As intervenções de educação em saúde demonstraram contribuir para a melhoria da saúde visual e ocular de usuários de computador com Síndrome de Visão de Computador. É preciso investigar e divulgar resulta-dos sobre o tema, que contribuam nos processos de promoção da saúde visual e ocular, bem como na prevenção da Síndrome da Visão do Computador no ambiente de trabalho

Digital eye strain among medical students associated with shifting to e-learning during COVID-19 pandemic: An online survey.

PURPOSE: This study aimed to determine the prevalence, risk factors, symptoms, and awareness of computer vision syndrome (CVS) among medical students during the coronavirus disease 2019 (COVID-19) pandemic. METHODS: A cross-sectional observational study was conducted among 283 undergraduate medical students at a tertiary healthcare center. An electronic survey was conducted to collect the data. Data were analyzed using Statistical Package for Social Sciences (SPSS version 23). The Chi-square test (Fisher's exact test when required) was used to study the significance of associations. A P value <0.05 was considered statistically significant. RESULTS: A high prevalence of CVS was observed in which 92% reported at least one symptom while using a digital device, the most frequent being eye strain (49%). Among extraocular complaints, joint pain in the wrist and fingers was most frequent. Significant association (P < 0.05) of CVS was found with increased duration of digital device usage, refractive error, use of glasses or contact lens, preexisting dry eye disease, and use of topical eye drops. 37% of the participants were aware of the 20-20-20 rule, while only 11% followed it. CONCLUSION: CVS is a common health concern among medical students. Hence, to increase the productivity of work, significant risk factors need to be addressed and awareness must be raised.

Computer vision syndrome and associated factors in university students and teachers in Nampula, Mozambique.

BACKGROUND: Computer Vision Syndrome (CVS) is a complex of eye and visual problems that arise while using a computer or other Video Display Terminal (DVT). With the advent of the COVID-19 pandemic, the use of these DVTs has become indispensable in the lives of students and teachers. This study aims to identify the prevalence of CVS and associated factors in students and teachers at Lúrio University, in Nampula, during the pandemic period. METHODS: This is a cross-sectional study, carried out between November 2020 and March 2021. The validated CVS questionnaire (CVS-Q) and another semi-structured questionnaire on ergonomic risk factors were applied. Odds ratios (OR) and adjusted odds ratios (aOR) were calculated to measure the association between CVS and computer use conditions. RESULTS: The prevalence of CVS was 76.6%, and the female gender, age ≤ 20 years, levels I, II, III of course, lack of knowledge about ergonomics, use the computer to study, use more than 6 hours daily, absence of anti-reflex treatment, use of other devices and sitting in an inappropriate chair were risk factors for the occurrence of CVS, while being a teacher was a protective factor. CONCLUSION: The prevalence of CVS found in this study was high, due to several factors, especially not using ergonomic principles when using computers and other DVTs. There is a need to adopt intervention strategies focused on the most vulnerable groups such as women, age group ≤20 years and students, especially at the first year level, right after entering the University.

Computer vision syndrome among students during remote learning periods: harnessing digital solutions for clear vision.

Aim: This study aimed to assess the prevalence of Computer Vision Syndrome (CVS) among children and adolescents in Qatar during the period of remote learning and explore the associated factors and discuss some digital health remedies that might reduce the risk. Methods: We conducted an analytical cross-sectional study between June and August 2022 by collecting data via telephone interviews with parents of selected students utilizing the Computer Vision Syndrome Questionnaire (CVS-Q). Results: We completed 1,546 interviews. The mean age of the students was (11 ± 2), male: female ratio was almost 1:1. About one quarter (368, 23.8%) of parents reported a previous diagnosis of visual disturbances among their children with over 88% of them wearing eyeglasses or medical contact lenses. The prevalence of CVS in our sample was about 8% (95%CI: 6.8-9.6). Mother's employment, having positive history of visual disturbances, and excess screen time were found to be significant predictors of CVS. Conclusion: Health care providers in collaboration with teachers should provide parents with evidence-based strategies to prevent or minimize the digital eye strain among students. In the landscape of remote learning, the implementation of digital remedies emerges as a proactive approach to mitigate the risk of digital eye strain.

The effect of blue light filter on visual and task performance.

PURPOSE: This study aimed to determine the effect of the blue light (BL) filter on the different tasks performed on a laptop on a daily basis. METHODS: Forty subjects were required to perform a 45-minute task on the laptop screen with or without the BL filter on two different days. In the first task, subjects were made to watch a video. In the second task, subjects were made to read a passage from the laptop for 3 minutes, and reading speed was calculated. In the third task, subjects were made to enter the data on the laptop. The time taken to fill in the data was recorded. After the completion of the task, questionnaires were administered. Pre- and post-task accommodative tests were performed. RESULTS: Forty emmetropes with a mean age of 21 ± 2 were recruited. In visual performance, the subjective response showed a significant difference in visual fatigue level with and without the filter. A statistically significant difference was seen in reading speed and data entry during task performance with and without the filter. Pre- and post-task accommodative parameters showed variable responses. CONCLUSION: This study showed that the use of a BL filter improves task performance, but subjectively, people experienced more visual fatigue while using the filter.

Plant bioactive compounds alleviate photoinduced retinal damage and asthenopia: Mechanisms, synergies, and bioavailability.

The retina, an important tissue of the eye, is essential in visual transmission and sustaining adequate eyesight. However, oxidative stress and inflammatory reactions can harm retinal structure and function. Recent studies have demonstrated that exposure to light can induce oxidative stress and inflammatory reactions in retinal cells, thereby facilitating the progression of retinal damage-related diseases and asthenopia. Plant bioactive compounds such as anthocyanin, curcumin, resveratrol, lutein, zeaxanthin, epigallocatechin gallate, and quercetin are effective in alleviating retinal damage and asthenopia. Their strong oxidation resistance and unique chemical structure can prevent the retina from producing reactive oxygen species and regulating eye muscle relaxation, thus alleviating retinal damage and asthenopia. Additionally, the combination of these active ingredients produces a stronger antioxidant effect. Consequently, understanding the mechanism of retinal damage caused by light and the regulation mechanism of bioactive compounds can better protect the retina and reduce asthenopia.

The changes and causes of asthenopia after ICL implantation.

OBJECTIVE: To detect the presence of asthenopia after implantation of Implantable Collamer Lens (ICL). METHOD: Design: prospective observational case series. Patients with myopia and/or astigmatism who underwent ICL surgeries and completed 3-month follow-up were enrolled. Asthenopia scores, amplitude of accommodation (AA), positive/negative relative accommodation (PRA/NRA), accommodative facility (AF), the ratio of accommodative convergence and accommodation (AC/A), Schirmer test, noninvasive breakup time (NBUT), and HOA were examined before surgeries and at 1 week, 1 month and 3 months postoperatively then statistically analyzed. RESULTS: Symptoms of asthenopia were significantly decreased at 1 week after ICL surgeries than those before surgeries, but increased gradually as time went by, eventually recovered at 3 months postoperatively. AA, AF, AC/A decreased 1 week postoperatively, returned to the baseline at 1 month and were improved at 3 months after surgeries. NBUT at 1 week, 1 month and 3 months after surgeries were significantly decreased and was the lowest at 1 week postoperatively. PRA, NRA, Schiermer values and HOA had no significant change. Correlation analysis showed that the lower AF and NBUT after ICL surgeries, the more severe the asthenopia symptoms. CONCLUSION: The symptoms of asthenopia aggravated transiently after ICL implantation surgeries, but improved gradually with time. AF and NBUT were important factors affecting the changes of asthenopia.

A Neurophysiological Evaluation of Cognitive Load during Augmented Reality Interactions in Various Industrial Maintenance and Assembly Tasks.

Augmented reality (AR) has been shown to improve productivity in industry, but its adverse effects (e.g., headaches, eye strain, nausea, and mental workload) on users warrant further investigation. The objective of this study is to investigate the effects of different instruction methods (i.e., HoloLens AR-based and paper-based instructions) and task complexity (low and high-demanding tasks) on cognitive workloads and performance. Twenty-eight healthy males with a mean age of 32.12 (SD 2.45) years were recruited in this study and were randomly divided into two groups. The first group performed the experiment using AR-based instruction, and the second group used paper-based instruction. Performance was measured using total task time (TTT). The cognitive workload was measured using the power of electroencephalograph (EEG) features and the NASA task load index (NASA TLX). The results showed that using AR instructions resulted in a reduction in maintenance times and an increase in mental workload compared to paper instructions, particularly for the more demanding tasks. With AR instruction, 0.45% and 14.94% less time was spent on low- and high-demand tasks, respectively, as compared to paper instructions. According to the EEG features, employing AR to guide employees during highly demanding maintenance tasks increased information processing, which could be linked with an increased germane cognitive load. Increased germane cognitive load means participants can better facilitate long-term knowledge and skill acquisition. These results suggested that AR is superior and recommended for highly demanding maintenance tasks since it speeds up maintenance times and increases the possibility that information is stored in long-term memory and encrypted for recalls.

Blue-light filtering spectacle lenses for visual performance, sleep, and macular health in adults.

BACKGROUND: 'Blue-light filtering', or 'blue-light blocking', spectacle lenses filter ultraviolet radiation and varying portions of short-wavelength visible light from reaching the eye. Various blue-light filtering lenses are commercially available. Some claims exist that they can improve visual performance with digital device use, provide retinal protection, and promote sleep quality. We investigated clinical trial evidence for these suggested effects, and considered any potential adverse effects. OBJECTIVES: To assess the effects of blue-light filtering lenses compared with non-blue-light filtering lenses, for improving visual performance, providing macular protection, and improving sleep quality in adults. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL; containing the Cochrane Eyes and Vision Trials Register; 2022, Issue 3); Ovid MEDLINE; Ovid Embase; LILACS; the ISRCTN registry; ClinicalTrials.gov and WHO ICTRP, with no date or language restrictions. We last searched the electronic databases on 22 March 2022. SELECTION CRITERIA: We included randomised controlled trials (RCTs), involving adult participants, where blue-light filtering spectacle lenses were compared with non-blue-light filtering spectacle lenses. DATA COLLECTION AND ANALYSIS: Primary outcomes were the change in visual fatigue score and critical flicker-fusion frequency (CFF), as continuous outcomes, between baseline and one month of follow-up. Secondary outcomes included best-corrected visual acuity (BCVA), contrast sensitivity, discomfort glare, proportion of eyes with a pathological macular finding, colour discrimination, proportion of participants with reduced daytime alertness, serum melatonin levels, subjective sleep quality, and patient satisfaction with their visual performance. We evaluated findings related to ocular and systemic adverse effects. We followed standard Cochrane methods for data extraction and assessed risk of bias using the Cochrane Risk of Bias 1 (RoB 1) tool. We used GRADE to assess the certainty of the evidence for each outcome. MAIN RESULTS: We included 17 RCTs, with sample sizes ranging from five to 156 participants, and intervention follow-up periods from less than one day to five weeks. About half of included trials used a parallel-arm design; the rest adopted a cross-over design. A variety of participant characteristics was represented across the studies, ranging from healthy adults to individuals with mental health and sleep disorders. None of the studies had a low risk of bias in all seven Cochrane RoB 1 domains. We judged 65% of studies to have a high risk of bias due to outcome assessors not being masked (detection bias) and 59% to be at high risk of bias of performance bias as participants and personnel were not masked. Thirty-five per cent of studies were pre-registered on a trial registry. We did not perform meta-analyses for any of the outcome measures, due to lack of available quantitative data, heterogenous study populations, and differences in intervention follow-up periods. There may be no difference in subjective visual fatigue scores with blue-light filtering lenses compared to non-blue-light filtering lenses, at less than one week of follow-up (low-certainty evidence). One RCT reported no difference between intervention arms (mean difference (MD) 9.76 units (indicating worse symptoms), 95% confidence interval (CI) -33.95 to 53.47; 120 participants). Further, two studies (46 participants, combined) that measured visual fatigue scores reported no significant difference between intervention arms. There may be little to no difference in CFF with blue-light filtering lenses compared to non-blue-light filtering lenses, measured at less than one day of follow-up (low-certainty evidence). One study reported no significant difference between intervention arms (MD - 1.13 Hz lower (indicating poorer performance), 95% CI - 3.00 to 0.74; 120 participants). Another study reported a less negative change in CFF (indicating less visual fatigue) with high- compared to low-blue-light filtering and no blue-light filtering lenses. Compared to non-blue-light filtering lenses, there is probably little or no effect with blue-light filtering lenses on visual performance (BCVA) (MD 0.00 logMAR units, 95% CI -0.02 to 0.02; 1 study, 156 participants; moderate-certainty evidence), and unknown effects on daytime alertness (2 RCTs, 42 participants; very low-certainty evidence); uncertainty in these effects was due to lack of available data and the small number of studies reporting these outcomes. We do not know if blue-light filtering spectacle lenses are equivalent or superior to non-blue-light filtering spectacle lenses with respect to sleep quality (very low-certainty evidence). Inconsistent findings were evident across six RCTs (148 participants); three studies reported a significant improvement in sleep scores with blue-light filtering lenses compared to non-blue-light filtering lenses, and the other three studies reported no significant difference between intervention arms. We noted differences in the populations across studies and a lack of quantitative data. Device-related adverse effects were not consistently reported (9 RCTs, 333 participants; low-certainty evidence). Nine studies reported on adverse events related to study interventions; three studies described the occurrence of such events. Reported adverse events related to blue-light filtering lenses were infrequent, but included increased depressive symptoms, headache, discomfort wearing the glasses, and lower mood. Adverse events associated with non-blue-light filtering lenses were occasional hyperthymia, and discomfort wearing the spectacles. We were unable to determine whether blue-light filtering lenses affect contrast sensitivity, colour discrimination, discomfort glare, macular health, serum melatonin levels or overall patient visual satisfaction, compared to non-blue-light filtering lenses, as none of the studies evaluated these outcomes. AUTHORS' CONCLUSIONS: This systematic review found that blue-light filtering spectacle lenses may not attenuate symptoms of eye strain with computer use, over a short-term follow-up period, compared to non-blue-light filtering lenses. Further, this review found no clinically meaningful difference in changes to CFF with blue-light filtering lenses compared to non-blue-light filtering lenses. Based on the current best available evidence, there is probably little or no effect of blue-light filtering lenses on BCVA compared with non-blue-light filtering lenses. Potential effects on sleep quality were also indeterminate, with included trials reporting mixed outcomes among heterogeneous study populations. There was no evidence from RCT publications relating to the outcomes of contrast sensitivity, colour discrimination, discomfort glare, macular health, serum melatonin levels, or overall patient visual satisfaction. Future high-quality randomised trials are required to define more clearly the effects of blue-light filtering lenses on visual performance, macular health and sleep, in adult populations.

[Development of an asthenopia survey questionnaire for general surveys].

Objective: To design a visual fatigue questionnaire that can be used for population surveys. Methods: This was a cross-sectional study that involved three stages of subjects' recruitment. In the first stage, by convenience sampling, 150 individuals who complained of visual fatigue were selected at public places in Wenzhou City in May 2016. The 19-Item Asthenopia Survey Questionnaire (ASQ-19) was used to conduct the survey, and the questionnaire was adjusted. In the second stage, 200 outpatient participants were recruited from Wenzhou Medical University Affiliated Eye and Optometry Hospital from June 2016 to May 2017 and were divided into a visual fatigue group and a control group based on clinical diagnosis. The adjusted visual fatigue questionnaire was used for validation. In the third stage, 64 outpatient participants who met the inclusion criteria were continuously recruited from the Wenzhou Medical University Affiliated Eye and Optometry Hospital in July 2022. They were tested using the adjusted visual fatigue questionnaire and retested one week later. During the questionnaire adjustment stage, factor analysis and feedback were used to adjust the scoring method and items of the ASQ-19 questionnaire. The adjusted questionnaire was then analyzed for reliability, validity, accuracy, and subject acceptance during the validation and retest stages. Results: A total of 403 participants were included, and 456 questionnaires were distributed. Eventually, 432 valid questionnaires were collected from 379 participants, resulting in a valid response rate of 94.7%. During the questionnaire adjustment phase, there were 140 valid questionnaires from 140 participants consisting of 56 males and 84 females with an average age of (35.2±12.4) years. In the questionnaire validation phase, there were 186 valid questionnaires from 186 participants. Sixty-two participants had visual fatigue and 124 were controls. During the questionnaire retesting phase, 53 participants yielded 106 valid questionnaires. The group consisted of 20 males and 33 females with an average age of (22.8±4.9) years. After factor analysis, the symptom severity graded as none, mild, moderate, severe, and very severe was scored as 0, 1, 2, 3, and 4 points, respectively. The total score was 44, and the final questionnaire consisted of 11 items (numbered 1, 2, 3, 5, 6, 8, 10, 15, 17, 18, and 19). The 11-Item Asthenopia Survey Questionnaire (ASQ-11) had a Cronbach's α coefficient of 0.89, a split-half reliability of 0.82, and a test-retest Pearson correlation coefficient of 0.90 (P<0.001). The structural validity was 51.26%, and the discriminative validity was a t-value of 9.19 (P<0.001). On average, it took (2.82±0.43) minutes for participants to complete the questionnaire. The receiver operating characteristic curve had a cutoff value of 8.5, with a sensitivity of 74.19% and a specificity of 80.65%. Conclusion: The ASQ-11, with fewer items and a shorter completion time, is easy for participants to use and is suitable for screening or self-assessment of visual fatigue in the general population. Additionally, it is convenient for clinical and epidemiological studies related to visual fatigue.