Effects of prolonged continuous computer gaming on physical and ocular symptoms and binocular vision functions in young healthy individuals

The status of binocular visual functions among Taiwan high-tech industry engineers and its correlation with computer vision symptom

To analyze the status of binocular visual functions, the relationship between binocular visual function and computer vision-related symptoms in the high-tech industry group. The study sample was comprised of 33 participants aged between 20 and 40 years of age. After completing basic information and the Computer Vision Symptom Scale (CVSS-17) questionnaire, the participants underwent a comprehensive examination of binocular visual function. All data were statistically analyzed with SPSS V26.0 software. The value of the binocular vision function of the Taiwan high-tech industry group was significantly different compared with the Scheiman and Morgan standard value. Study subjects were generally found to exhibit larger exophoric at distance, which in turn might lead to a lower ability to maintain binocular fusion to a single image, or recover from fusional disruption at distance. Subjects also experienced accommodation and convergence problems at near at the same time. Age, gender, and refractive errors had no significant impact on CVSS-17 scores, only the duration of computer usage showed a significant effect, particularly for internal symptom factor (ISF) dimensions. In addition, the interaction between the ISF and external symptom factor resulted in more severe visual symptoms. Long-term use of electronic devices may lead to an imbalance in binocular vision function, thereby increasing or exacerbating visual symptoms. If the use of electronic devices is an unchangeable trend, interventions in prescription, visual training or the visual design of electronic products become worthwhile topics for development.

Diurnal Variation in Accommodation, Binocular Vergence, and Pupil Size

SIGNIFICANCE

Our results show significant diurnal variations in accommodative function and the magnitude of the phoria. Therefore, when comparing visual measures in clinical or laboratory settings, performing the visual examination at the same time of day (±1 hour) is encouraged.

PURPOSE

The aim of this study was to evaluate the accommodation, binocular vergence, and pupil behavior on three different times during the day.

METHODS

Twenty collegiate students (22.8 ± 2.1 years) participated in this study. Participants visited the laboratory on three different days at 2-hourly intervals (morning, 9:00 to 11:00 am ; afternoon, 2:00 to 4:00 pm ; evening, 7:00 to 9:00 pm ). The binocular vergence and accommodative function were measured using clinical optometric procedures, and the accommodative response and pupil function were evaluated in binocular conditions using the WAM-5500 autorefractometer.

RESULTS

The accommodative amplitude for the right and left eyes showed statistically significant differences for the time interval ( P = .001 and P = .02, respectively), revealing higher accommodative amplitude in the morning and afternoon in comparison with the evening. Participants were more esophoric when assessed in the morning in comparison with the evening at far and near ( P = .02 and P = .01, respectively) and when assessed in the afternoon in comparison with the evening at far distance ( P = .02). The magnitude of accommodative response was higher in the morning, and it decreased throughout the day at 500 ( P < .001), 40 ( P = .05), and 20 cm ( P < .001). No statistically significant differences were obtained for any other variable.

CONCLUSIONS

This study shows small diurnal variations in some accommodative and binocular vergence parameters, but no effects were observed for the pupil response. These outcomes are of special relevance for eye care specialists when performing repeated accommodative or binocular vergence measures. However, the diurnal variations were modest and may not influence a routine orthoptic examination.

Factors affecting upper limb ergonomics in robotic colorectal surgery

The aim of the study was to examine the factors which may influence suboptimal ergonomic surgeon hand positioning during robotic colorectal surgery (RCS). An observational study of 11 consecutive RCS cases from June 2022 to August 2022 was performed. Continuous video footage of RCS cases was analysed concurrently with video recordings of surgeon's hand positions at the console. The outcome studied was the frequency with which either hand remained in a suboptimal ergonomic position outside the predetermined double box outlines, as marked on the surgeon's video, for >1 min. Situations which resulted in poor upper limb ergonomics were dissection in the peripheral operating field location, left-hand use, use of the stapler, dissection of the main mesenteric blood vessels, and multi-quadrant surgery. Being aware of situations when suboptimal ergonomic positions occur can allow surgeons to consciously compensate by using the clutch or pausing to take a rest break.

What does this paper add to the literature?

The study is important because it is the first to look at factors which may influence poor upper limb ergonomics during non-simulated RCS. By recognizing these factors and compensating for them, it may improve surgeon ergonomics with resultant better performance.

Visualisation ergonomics and robotic surgery

Stereopsis may be an advantage of robotic surgery. Perceived robotic ergonomic advantages in visualisation include better exposure, three-dimensional vision, surgeon camera control, and line of sight screen location. Other ergonomic factors relating to visualisation include stereo-acuity, vergence-accommodation mismatch, visual-perception mismatch, visual-vestibular mismatch, visuospatial ability, visual fatigue, and visual feedback to compensate for lack of haptic feedback. Visual fatigue symptoms may be related to dry eye or accommodative/binocular vision stress. Digital eye strain can be measured by questionnaires and objective tests. Management options include treatment of dry eye, correction of refractive error, and management of accommodation and vergence anomalies. Experienced robotic surgeons can use visual cues like tissue deformation and surgical tool information as surrogates for haptic feedback.

Determinants of digital eye strain among university students in a district of India: a cross-sectional study

Aim

Digital device usage, especially during the pandemic, has catapulted into a new age problem, the computer vision syndrome. This study aimed to quantify the prevalence and determinants of digital eye strain (DES).

Subject and Methods

A total of 345 university students in India were surveyed in June-July 2022, by a validated tool, the Computer Vision Syndrome Questionnaire (CVS-Q) © in this cross-sectional study. According to American Optometric Association, digital eye strain and computer vision syndrome are synonyms. Non-parametric tests of medians were used to compare the median DES scores, Chi square test to compare categorical variables, and binary logistic regression to find the determinants of DES.

Results

The average age of the study participants was 21.0 ± 2.2 years, ranging between 18-26 years with 52.8% females and 47.2% males. The prevalence of DES was 45.5% (CI 95% = 40.2%-50.8%). Any existing eye disease (p-value = 0.000, OR = 0.41, 95% CI = 0.26-0.65), average daily screen time (p-value = 0.001, OR = 1.61, 95% CI = 1.22-2.13) and using gadgets in the dark (p-value = 0.000, OR = 0.37, 95% CI = 0.23-0.61) were significant determinants of the same.

Conclusion

Framing guidelines limiting the hours allotted for online classes for university students are imperative, with promotion of ergonomic practices for digital device usage such as blue light filters and night mode on devices.

Improving Visual Comfort during Computer Gaming with Preservative-Free Hyaluronic Acid Artificial Tears Added to Ergophthalmological Measures

Digital asthenopia (DA) or Computer Vision Syndrome can occur after prolonged use of digital devices and is usually managed with ergophthalmological measures and the use of artificial tears. This prospective, controlled study evaluated the use of hyaluronic acid artificial tears on the signs and symptoms of DA in participants of a videogame convention. Subjects (n = 56) were randomized into a control group (CG, n = 26), which followed ergophthalmological measures, and a study group (SG, n = 30), which followed ergophthalmological measures and instilled 1 drop of artificial tears with hyaluronic acid 0.15% four times a day. Subjects were evaluated before and after playing for three consecutive days for eye dryness (SPEED questionnaire), conjunctival hyperemia, corneal fluorescein staining, conjunctival lissamine green staining, tear breakup time, Schirmer I test, near convergence and accommodation, and using questionnaires for DA symptoms. After 3 days of intense videogaming, the SPEED score of CG increased significantly (p = 0.0320), while for the SG it was unchanged. Similarly, the CG presented significant increases in ocular fatigue (p = 0.0173) and dryness (p = 0.0463), while these parameters decreased significantly in the SG (p = 0.0149 and p = 0.00427, respectively). This study confirms the protective effect of hyaluronic acid artificial tears against DA symptoms associated with prolonged visual display terminal use.

Risk factors and outcomes of internet gaming disorder identified in Korean prospective adolescent cohort study

BACKGROUND AND AIMS

Internet gaming disorder (IGD) is known to cause various psychological and physical complications. Through data collected from an adolescent prospective longitudinal cohort, we examined how IGD is related to lifestyle and physical symptoms, as well as the temporal relationship between them.

METHODS

This study was conducted as part of iCURE (Internet user Cohort for Unbiased Recognition of gaming disorder in Early Adolescence) in Korea between 2015 and 2019. Sleep and physical activity time, dry eye symptoms, musculoskeletal pain, and near-miss accidents were measured at baseline and followed-up after one year. IGD risk was evaluated using the Internet Game Use - Elicited Symptom Screen (IGUESS). The association between IGD risk and measured variables was analyzed, both at baseline and at follow-up after one year.

RESULTS

At baseline, the IGD risk group had significantly less physical activity time and sleep time and had more dry eye symptoms, musculoskeletal pain, and near-miss accidents than the IGD non-risk group. Additionally, in the IGD risk group at baseline, dry eye symptoms, musculoskeletal pain, and near-miss accidents occurred significantly more after one year of follow-up.

DISCUSSION AND CONCLUSION

The results of this study show that IGD is a significant risk factor that increases the probability of physical disease and trauma in adolescents. Therefore, interventions aimed at reducing IGD risk and protecting the physical and mental health of adolescents are imperative.

Tweenager Computer Visual Syndrome Due to Tablets and Laptops during the Postlockdown COVID-19 Pandemic and the Influence on the Binocular and Accommodative System

The aim of our study was to compare computer visual syndrome (CVS) in a tweenager student population who use tablets and laptops only to play versus CVS in tweenagers who use these digital devices at school to study, in addition to playing. The tests performed were a validated survey for children for the detection of CVS and accommodative and vergence tests. The CVS item questionnaire was divided into four main groups based on questions concerning the following: (I) the digital device usage time, (II) musculoskeletal and ergonomic nature, (III) visual symptoms, and (IV) ocular surface symptoms. The high-demand digital device group showed worse punctuation in all item groups. From the optometric perspective, when the subjects were classified according to the CVS, high-demand participants presented a clear tendency to exophoria with statistically significant differences in distance vision (−1.94 ± 4.48 Δ) and near vision (−5.78 ± 8.62 Δ) (p < 0.01). Our results establish a relationship between the increased use of electronic devices and computer vision syndrome in the preadolescent population. In addition, this situation is related to the presence of visual, accommodative, and binocular dysfunctions that could affect the efficiency of the visual system.

Online e-learning during the COVID-19 lockdown in Trinidad and Tobago: prevalence and associated factors with ocular complaints among schoolchildren aged 11-19 years

Background

The increase in online learning during the pandemic has been linked to various ocular complaints. This study determined the prevalence and factors associated with ocular complaints among schoolchildren aged 12-19 years during the COVID-19 lockdown in Trinidad and Tobago (T&T).

Methods

A cross-sectional study was conducted between January and May 2021, during the COVID-19 lockdown in T&T among secondary school students studying remotely. A two-stage cluster sampling method was employed. A modified web-based Computer Vision Syndrome questionnaire was administered to students. Data on demography, duration of digital device use, and ocular complaints were collected, and multilevel logistic regression was used to determine factors associated with ocular complaints among school children, 12-19 years of age in T&T.

Results

A total of 435 schoolchildren (mean age, standard deviation, 15.2 ± 1.9 years range 12-19 years) responded to the questionnaire. The prevalence of self-reported symptoms of headache, blurred vision, dry eyes, itchy eyes, and double vision were 75.0%, 65.1%; 56.8%; 46.4%; and 33.5%, respectively. Schoolchildren aged 18-19 years, those that used spectacles for correction of their refractive errors, and spent more than 6 h on average on digital devices, reported a high prevalence of any ocular complaints. Analysis also revealed that age (14-15 years) was associated with dry eyes, blurred vision, and headaches, while gender (more prevalently females) was associated with blurred vision and headache. Those that had an eye examination in the last year and schoolchildren that took action to resolve ocular complaints were more likely to experience nearly all ocular complaints.

Conclusions

During the COVID-19 lockdown, over three in four students in T&T reported ocular complaints from digital devices for online learning. Tailored interventional messages to reduce all forms of ocular complaints should target older students, particularly females, those who laid down when learning online via their devices and people who regularly examine their eyes.

AOASM Position Statement on Esports, Active Video Gaming, and the Role of the Sports Medicine Physician

ABSTRACT

Electronic sports, or esports, has a global audience of over 300 million fans and is increasing in popularity, resulting in projected revenue of over $1 billion by the end of this past year. The global pandemic of 2020 had little to no effect on these increasing numbers because athletes have been able to continue to engage in sports because of its electronic nature and fans have been able to follow them virtually. Esports has been recognized as an organized sport by the International Olympic Committee, the US National Collegiate Athletic Association, and several secondary school athletic associations within the United States. In addition, professional teams have been established in several major cities within the United States, Canada, Europe, and Australia. With the growth of esports, the necessity of incorporating esports medicine into the practice of sports medicine physicians has become paramount. Esports can be played on a monitor or screen and played using physical activity in what has become known as active video gaming. Within both of these platforms, there have emerged certain conditions unique to esports. There are also certain conditions seen in other sports applicable to esports athletes. This document will review the evaluation of the esports athlete, introduce conditions unique to these athletes and review common conditions seen in esports, discuss diagnostics used in the evaluation of esports athletes, introduce treatment options for conditions unique to esports and review those for commonly seen injuries in esports, discuss prevention of injuries in esports, and introduce a framework for the future development of esports medicine that can be introduced into the daily practice of the sports medicine physician.

Validation of the Digital Eye Strain Questionnaire and pilot application to online gaming addicts

INTRODUCTION

'Digital eye strain' (DES) is a clinical syndrome with eyesight symptoms related to continuous engagement in front of a screen-enabled digital device. With use of these devices constantly on the rise, the related symptoms have become prominent, even in younger ages. This study describes the process of validating the Digital Eye Strain Questionnaire (DESQ), a thirteen-item self-report scale in a yes-no format designed to offer a measure of complaints related to digital eye strain syndrome (DES).

METHODS

The validation process included 150 outpatients with no long-standing eye disease who were examined for various eye complaints and 50 outpatients who were diagnosed with gaming addiction according to WHO ICD-11 clinical criteria. All participants filled in a demographics questionnaire, the DESQ, the Computer Vision Syndrome Questionnaire (CVS-Q) and the Problematic Internet Use Questionnaire-9 (PIUQ-9).

RESULTS

Principal component analysis of categorical variables confirmed the proposed three-factor DES structure with a total of 61.02% of explained variance and Cronbach's alpha equal to.94. Concurrent validity was assessed by comparing the results of the DESQ to the CVS-Q while convergent validity was assessed by examining correlations of the DESQ with results from the PIUQ-9 questionnaire. In all cases the DESQ demonstrated excellent reliability and validity.

CONCLUSIONS

Results indicate that the DESQ questionnaire can be employed to reliably measure the symptomatology of digital eye strain in clinical populations who present either with eye issues or with excessive use of the gaming and screen-enabled devices in general.

Visual fatigue induced by watching virtual reality device and the effect of anisometropia

The effect of small anisometropia on visual fatigue when using virtual reality (VR) devices was investigated. Participants (n = 34) visited three times. In the first visit, VR exposure (10 min) was conducted with the full correction of the refractive error of both eyes. Experimental anisometropia was induced by adding a + 1.0 dioptre spherical lens either on the dominant eyes in the second visit or on the non-dominant eyes in the third visit. At each visit, the participants played a predetermined video game using a head-mounted display VR for 10 min. Visual fatigue was assessed before and after playing VR game using the Virtual Reality Symptom Questionnaire (VRSQ) and high-frequency component of accommodative microfluctuation. Results showed that watching VR induced significant increase of VRSQ score, significant decrease in the maximum accommodation power and objective increase in visual fatigue. Experimental anisometropia induction either on the dominant or non-dominant eyes did not aggravate visual fatigue. Practitioner summary: Mild differences in refractive error (up to 1.0 dioptre) between both eyes do not significantly increase ocular fatigue by viewing virtual reality device (10 min). The impact of small anisometropia may be limited in developing a virtual reality device. Abbreviations: VR: virtual reality; VRSQ: virtual reality symptom questionnaire; HMD: head-mounted display; HFC: high-frequency component.

Visual and Ocular Characteristics of eSports Participants

SIGNIFICANCE

The popularity of competitive video game play is growing rapidly. Little is known about the ocular characteristics of esports participants. Refractive error and binocular measures in young adult gamers were similar to population norms. However, tear breakup time was lower, and accommodative lag was higher.

PURPOSE

In a recent report, very young video game players were found to have greater levels of refractive error and heterophoria and reduced stereopsis. The purpose of this study was to assess the visual and ocular characteristics of a group of recreational esports athletes to determine if the findings in young children were similar to findings in a group of young adult video game players.

METHODS

Vision tests were performed on 36 college students during a video game combine event. Testing included high- and low-contrast visual acuity, autorefraction at distance and at 33 cm, stereoacuity, near heterophoria, and tear breakup time. Participants also indicated their level or rank in the game Overwatch.

RESULTS

Fifteen participants were myopic, and 21 did not wear vision correction. The mean local stereopsis was 31.9 seconds. The mean of the esophoric value was 3.2 prism diopters, and the mean of the exophoric value was 5.7 prism diopters. The mean lag of accommodation was 0.81 D. The mean tear breakup time was 5.8 seconds. Average hours of play did not differ between those who wore vision correction and those who did not. There were no significant relationships between the hours of play and the ocular findings.

CONCLUSIONS

The prevalence of refractive error and the mean heterophoria were similar to population norms, and the mean stereoacuity was normal. However, accommodative lag was slightly higher, and the tear breakup time was lower than expected. Differences in these latter values were also noted between high- and low-level Overwatch players.

Digital Addiction: Systematic Review of Computer Game Addiction Impact on Adolescent Physical Health

The advancement of technology has enabled powerful microprocessors to render high-quality graphics for computer gaming. Despite being intended for leisure purposes, several components of the games alongside the gamer’s environmental factors have resulted in digital addiction (DA) towards computer games such as massively multiplayer online games (MMOG). Excessive gaming among adolescents has various negative impacts on an individual. However, only a few researchers have addressed the impact of DA on physical health. Thus, the primary objective of this research is to study the impact of DA on physical health among Malaysian adolescents. This study focuses on Malaysian adolescents of ages 12–18 years old who are addicted to computer games, specifically the MMOG. The methodology used for the study involves focus group discussions (FGD) and extensive literature study. The FGD sessions have involved both medical experts and game experts. The outcome of FGD discussion is recorded and justified with the existing relevant literature from high-impact journals, theses, conferences, books, and reports. This paper provides evidence of five physical health impacts of DA associated with adolescents. The factors of DA, the addiction components existing in MMOG computer games, and the DA health risk assessment are presented in the results section. Based on the study, it is concluded that DA among Malaysian adolescents can cause various impacts on physical health such as obesity, back pain, and neck pain, orthopaedic/joint muscle, eyesight problem, hearing problem, as well as physical inactivity.

Robotic colorectal surgery and ergonomics

Improved ergonomics for the operating surgeon may be an advantage of robotic colorectal surgery. Perceived robotic ergonomic advantages in visualisation include better exposure, three-dimensional vision, surgeon camera control, and line of sight screen location. Postural advantages include seated position and freedom from the constraints of the sterile operating field. Manipulation benefits include articulated instruments with seven degrees of freedom movement, elimination of fulcrum effect, tremor filtration, and scaling of movement. Potential ergonomic detriments of robotic surgery include lack of haptic feedback, visual, and mental strain from increased operating time and interruptions to workflow from crowding.

Accommodative and binocular disorders in preteens with computer vision syndrome: a cross-sectional study

To assess computer vision syndrome (CVS) in a preteen population through an adult-validated CVS questionnaire and to evaluate how digital devices affect accommodative and binocular vision, we enrolled 309 preteens in this cross-sectional study. An adult-validated CVS questionnaire adapted to preteens was used for all subjects. Visual acuity testing, unilateral and alternate cover tests, and tests for accommodative and vergence responses were performed for all preteens. The mean age was 10.75 ± 0.67 (10-12) years. Subjects were divided into two groups: the mild CVS group with a mean CVS score ≤2 and the severe CVS group with a mean CVS score >2. Between the mild and severe CVS groups, statistically significant differences were found in near point of convergence break and recovery (P = 0.03 and P = 0.02, respectively) and distance negative fusional vergence break and recovery (P = 0.02 and P < 0.01, respectively). More children with severe CVS developed vergence disorders than those with mild CVS. Optometric clinical screening assessments could reduce ocular symptomatology and prevent long-term effects. However, poor optometric findings might have occurred first, and the poor convergence skills resulted in the symptoms reported while using devices.

Digital Eye Strain Epidemic amid COVID-19 Pandemic - A Cross-sectional Survey

Purpose: There has been an enormous increase in the use of gadgets for online classes and entertainment during the COVID-19 pandemic. This study aimed to estimate the prevalence of digital eye strain (DES), describe the pattern of gadget usage, and analyse the risk factors for DES.Methods: This online survey analysed 941 responses from students of online classes (688), teachers of online classes (45), and general population (208). A pre-validated questionnaire was used to calculate the DES score. Non-parametric tests of medians were used to compare the median DES score, Chi-square test to compare categorical variables, and binary logistic regression to find the predictors of DES.Results: The prevalence of eye strain was higher among students taking online classes compared to the general public (50.6% vs 33.2%; χ² = 22.5, df = 1, p < .0001). There was an increase in screen time during the pandemic compared to pre-pandemic time. The DES score was highest among students attending online classes (p < .0001), in those with eye diseases (p = .001), greater screen time (p = <0.0001), screen distance <20 cm (p = .002), those who used gadgets in dark (p = .017) and those who took infrequent/no breaks (p = .018). The DES scores were proportional to the increase in the number of hours of gadget usage during the pandemic.Conclusion: There is a need to educate people about limiting overall screen exposure and ergonomic methods of screen viewing. Efforts from policymakers to reduce the duration of online classes for students and online work hours for professionals are warranted to control this epidemic of eye strain.

The Impact of Internet and Videogaming Addiction on Adolescent Vision: A Review of the Literature

During the past decade, vision problems that were attributed to the use of electronic screens have gradually shifted from being a workplace health issue to a wider public health issue. “Computer vision syndrome” originally related to the few professionals exposed to long hours of work in front of a computer screen. The widespread use of digital screens in devices used throughout the day have led to the emergence of “digital eye strain” as a new clinical syndrome that affects every individual who spends a large period of time fixated on multiple screens, for work or leisure. A new subcategory, “video game vision” has been proposed to specifically address vision issues related to large periods of continuous use of screen enabled devices in order to play video games. With gaming disorder being included in the next version of the WHO classification of diseases (ICD-11), it is becoming increasingly important to have a clear idea of the impact of this disorder in general health and functioning. At the same time, a number of research studies have reported positive impact of videogame playing on the players vision. This article reviews the latest research studies on the impact of digital screen enabled devices on adolescent vision in light of the increasing reports of internet addiction and gaming disorder while referencing positive findings of videogaming on vision in order to provide a balanced approach and assist with classification, diagnosis and treatment, while providing directions for future research.

Preliminary evaluation of the VIsion PERformance (VIPER) simulator

BACKGROUND

This study evaluated the VIsion PERformance (VIPER) simulator's ability to assess the functional visual performance in warfighters conducting civilian and military tasks.

METHODS

Thirty service members, aged 25-35 years old with a best corrected distance visual acuity (VA) better than or equal to 20/20 or logarithm of the minimum angle of resolution (logMAR) 0.00, were randomized to locate and identify road signs and mock improvised explosive devices (IEDs) under either daytime conditions or with infrared imagery, with (cc) and without (sc) wearing their habitual correction. Participants also underwent binocular uncorrected (UDVA) and corrected (CDVA) visual assessment, refraction, contrast sensitivity testing and wavefront aberrometry.

RESULTS

The mean age was 28.47 years. The manifest spherical equivalent was - 3.16 ± 1.75 diopters (D), the UDVA in both eyes (OU) was logMAR 0.83 ± 0.47, and the CDVA OU was - 0.11 ± 0.06. For VIPER, the mean difference in the detection distance (DD) for road signs ccDD vs. scDD was 76.7 ± 52.8 m (P < 0.001). The average difference in identification distance (ID) ccID vs. scID was 13.9 ± 6.3 m (P < 0.001). The mean accuracies were 83.5 and 27.9% for cc and sc, respectively (P < 0.001). The regression analysis indicated that a 1.6 m change in the distance accounts for a 1% change in the accuracy (P = 0.002). Without correction, a 4.1 m change accounts for a 1% change in the accuracy (P < 0.001). The average IED ccDD was 29.9 ± 8.2 m, and that for scDD was 13.2 ± 13.6 m (P < 0.001). The average IED ccID was 32.2 ± 6.2 m and that for the scID was 7.4 ± 10.3 m (P < 0.001). The mean IED identification accuracy was 46.7 and 11.4% for cc and sc, respectively (P < 0.001).

CONCLUSIONS

The preliminary results reflect VIPER's ability to assess functional visual performance when detecting and identifying signs and IEDs. Furthermore, VIPER is able to detect performance changes with and without correction.