To measure the amount of ocular deviation in strabismus patients with an eye-tracking virtual reality headset

Esterman Visual Field Testing Using a Virtual Reality Headset in Glaucoma

Purpose

To test the use of a virtual reality visual field headset (VRVF) for implementation of the Esterman visual field (EVF) test as compared with standard automated perimetry (SAP) among people with glaucoma.

Design

Experimental design.

Subjects

Patients with mild to severe glaucoma ranging from 10 to 90 years who presented for follow-up at a glaucoma clinic in Miami, Florida were eligible.

Methods

Participants performed the EVF test on both SAP and VRVF. Five glaucoma-trained ophthalmologists were then asked to rate all anonymized SAP and RVF tests as a "pass" or "failure" based on Florida state law.

Main Outcome Measures

Point-by-point concordance between original VRVF EVF test results and SAP EVF test results was calculated using the Kappa statistic. Concordance between SAP and VRVF was secondarily assessed with a conditional logistic regression based on the pass-failure determinations by the glaucoma-trained ophthalmologists. Interrater agreement on test pass-failure determinations was also calculated. Finally, test results on SAP versus VRVF were compared based on Esterman efficiency score (EES), the number of correct points divided by the number of total points, and duration of testing.

Results

Twenty-two subjects were included in the study with ages ranging from 14 to 78 years old. Concordance between VRVF and SAP test using point-by-point analysis was poor (κ = 0.332, [95% confidence intervals {CI}: 0.157, 0.506]) and somewhat increased using pass-failure determinations from ophthalmologists (κ = 0.657, [95% CI: 0.549, 0.751]). Ophthalmologists were more likely to agree amongst themselves on pass-failure determinations for VRVF tests (κ = 0.890, [95% CI: 0.726, 0.964]) than for SAP (κ = 0.590, [95% CI: 0.372, 0.818]); however, VRVF demonstrated significantly lower EES than SAP (median EES difference: 4.5 points, P = 0.021).

Conclusions

This pilot study is the first to assess the implementation of the EVF test using a virtual reality headset. Based on the weak overall agreement between VRVF and SAP, the current VRVF EVF test is not an acceptable determinant of driver's licensing. However, ophthalmologists were more likely to agree amongst themselves on VRVF test reports than on SAP reports. With further testing and improvement, virtual reality may eventually become a portable and convenient method for administering the EVF test.

Financial Disclosures

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Virtual Reality With Eye Tracking for Pediatric Ophthalmology: A Systematic Review

Virtual reality presents an efficient and engaging approach to ophthalmological diagnosis and treatment in children. This systematic review investigates the current state of eye tracking technology integrated into virtual reality for the spectrum of pediatric ophthalmology. The search encompassed the MEDLINE database via PubMed, without imposing any time restrictions. A total of 20 relevant studies that met our inclusion criteria were incorporated and categorized into the following domains: diagnosis, examination, treatment, and rehabilitation use of virtual reality devices within the realm of pediatric ophthalmology. Strabismus examinations and postoperative monitoring, inherited retinal degeneration examination and visual function testing, therapy of amblyopia, glaucoma visual field testing, cerebral visual impairment rehabilitation, and neuro-ophthalmic disease examination were included in the final analysis. Pediatric ophthalmology offers a promising landscape for the integration of eye tracking technology within virtual reality, with accelerated, quantifiable, and objective examination and diagnosis, and precise, real-time measurements that are crucial in children. Virtual reality is an engaging experience, easily applied in a pediatric setting and facilitating compliance during examination and adherence to therapy. Although our systematic review provides insights into the current state of research, it is anticipated that further exploration is required for the widespread utilization of eye tracking in virtual reality within pediatric ophthalmology. [J Pediatr Ophthalmol Strabismus. 20XX;X(X):XX-XX.].

The Role of Telemedicine in Strabismus Assessment: A Narrative Review and Meta-Analysis

Purpose: Strabismus is a common ocular condition requiring precise quantification of gaze deviation and qualification of strabismus category. Telemedicine refers to the use of technology to remotely diagnose and treat medical conditions. This narrative review aimed to assess the efficacy of a variety of telemedicine modalities for the assessment of strabismus. A secondary objective was to quantify overall accuracy, sensitivity, and specificity of automated methods using meta-analysis of available data. Methods: A literature search was conducted using the Ovid MEDLINE, Embase, and Cochrane Library data libraries. Keywords, including "strabismus," "phoria," "telemed*," and "telehealth," were used to locate relevant studies, with Medical Subject Headings terms, free text, and synonyms. No year restrictions were applied. Studies not in English were excluded. Risk of bias was assessed using the QUADAS-2 tool. Results: Thirty-four studies were included. All outcomes relating to accuracy and reliability of telemedicine versus a reference standard were extracted, as well as qualitative observations. High sensitivity, specificity, accuracy, and agreement were consistently shown across studies. Meta-analysis of two subsets featuring automated methods, for which relevant data were available, revealed a pooled accuracy of 0.877 (0.806-0.949), sensitivity of 0.856 (0.805-0.907), and specificity of 0.900 (0.845-0.954). Subcategories "remote standard assessment," "digital image analysis," "wearable devices," "mobile health (mHealth)," and "artificial intelligence" were independently examined. Conclusions: The majority of systems achieved parity with standard physician assessment, with the added benefit of eliminating subjectivity. Meta-analysis results suggest potential introduction of remote automated assessment where conventional assessment is unavailable, although accuracy of current technologies remains limited compared to in-person examination. Telemedicine modalities described offer convenience for patients, shorter examination times, and the potential to go beyond in-person assessments. The evidence gathered in this review supports the beginning of telemedicine integration into the world of strabismus diagnosis.

Usefulness Assessment of Automated Strabismus Angle Measurements Using Innovative Strabiscan Device

BACKGROUND

The variability of the obtained results of manual tests assessing the angle of strabismus depends on the experience, skills, and training of the examiner. The authors hope that this new measuring device will provide a more sensitive and repeatable method for detecting small strabismus angles compared to the gold standard-PCT. The purpose of this article is to present an innovative strabismus angle demonstration device, called Strabiscan, to provide automated measurements of eye deviation and to compare the obtained results of these measurements to the traditional manual method.

METHODS

For patients with manifest strabismic disease (n = 30) and a group of healthy subjects (n = 30), a detailed history was taken and routine ophthalmologic examinations were performed, including best-corrected distance visual acuity, assessment of refractive error using an autorefractometer after cycloplegia, biomicroscopic evaluation of the anterior segment of the eye and evaluation of the eye fundus by indirect ophthalmoscopy. Subsequently, each patient and healthy subject was subjected to a prismatic cover-uncover test using a manual method, after which the presence of strabismus was detected and its angle assessed using a Strabiscan demonstration device.

RESULTS

In the control group using the Strabiscan demonstration device, small-angle latent strabismus ≤ 3DP was diagnosed in 83% of patients, while >3DP was found in 13%. In contrast, using the prismatic cover-uncover test, latent strabismus ≤ 3DP was diagnosed in only 13% of patients, and latent strabismus with an angle > 3DP was found in 13% of patients. No statistically significant differences were noted in the measurements of strabismus angles made by the different methods.

CONCLUSIONS

The Strabiscan demonstration device allows quick and accurate assessment of the strabismus angle. Compared to the prismatic cover-uncover test, it has a higher sensitivity for detecting low-angle latent strabismus. Measurements with the Strabiscan do not require the presence of additional assistants for the test.

Table tennis players use superior saccadic eye movements to track moving visual targets

Introduction

Table tennis players perform visually guided visuomotor responses countlessly. The exposure of the visual system to frequent and long-term motion stimulation has been known to improve perceptual motion detection and discrimination abilities as a learning effect specific to that stimulus, so may also improve visuo-oculomotor performance. We hypothesized and verified that table tennis players have good spatial accuracy of saccades to moving targets.

Methods

University table tennis players (TT group) and control participants with no striking-sports experience (Control group) wore a virtual reality headset and performed two ball-tracking tasks to track moving and stationary targets in virtual reality. The ball moved from a predetermined position on the opponent's court toward the participant's court. A total of 54 conditions were examined for the moving targets in combinations of three ball trajectories (familiar parabolic, unfamiliar descent, and unfamiliar horizontal), three courses (left, right, and center), and six speeds.

Results and discussion

All participants primarily used catch-up saccades to track the moving ball. The TT group had lower mean and inter-trial variability in saccade endpoint error compared to the Control group, showing higher spatial accuracy and precision, respectively. It suggests their improvement of the ability to analyze the direction and speed of the ball's movement and predict its trajectory and future destination. The superiority of the spatial accuracy in the TT group was seen in both the right and the left courses for all trajectories but that of precision was for familiar parabolic only. The trajectory dependence of improved saccade precision in the TT group implies the possibility that the motion vision system is trained by the visual stimuli frequently encountered in table tennis. There was no difference between the two groups in the onset time or spatial accuracy of saccades for stationary targets appearing at various positions on the ping-pong table.

Conclusion

Table tennis players can obtain high performance (spatial accuracy and precision) of saccades to track moving targets as a result of motion vision ability improved through a vast amount of visual and visuo-ocular experience in their play.

Feasibility study of an automated Strabismus screening Test using Augmented Reality and Eye-tracking (STARE)

BACKGROUND

New digital technologies (augmented reality headsets, eye-tracking) may potentially allow for automated assessments of ocular misalignment. Here, we evaluate the feasibility of a novel, open-source strabismus test ("STARE") as an automated screening tool.

METHODS

Work progressed in 2 phases. In phase 1 ("development"), we used Fresnel prisms to elicit horizontal misalignments of known magnitude (1-40 prism dioptres) in orthotropic controls. In phase 2 ("validation"), we applied the system to adults with an established diagnosis of strabismus, and quantified the ability of the test to distinguish between those with horizontal misalignment and those without. Agreement between the alternate prism cover test measurements and STARE measurements was computed using Bland-Altman plots and product-moment correlation coefficients.

RESULTS

Seven orthotropic controls and nineteen patients with strabismus were recruited (mean age 58.7 ± 22.4 years). STARE was able to identify the presence of horizontal strabismus with an area under the curve of 1.00 (100% sensitivity and 100% specificity). The mean difference (bias) {95% CI} was 2.1 {-1.8, 9.9} prism dioptres, and the 95% coefficient of repeatability {95% CI} was ±27.9 {14.8, 50.8} prism dioptres. The Pearson correlation between APCT and STARE was r24 = 0.62, P < 0.001.

CONCLUSIONS

STARE shows promise as a simple, automated tool for performing a screening assessment of strabismus. It is a rapid (60 s) test that can be performed using a consumer augmented reality headset with integrated eye-tracking, and might conceivably be used remotely by non-specialists in future as a means of highlighting individuals needing face-to-face specialist care.

Comparative Analysis of Strabismus Measurement Using a Video Oculagraphy System and Alternate Prism Cover Test

PURPOSE

The aim of the study was to compare distance vision measurements obtained with video oculography (VOG) and an alternate prism cover test (APCT).

DESIGN

Single-center, retrospective, and cross-sectional.

METHODS

Eighty-seven subjects with strabismus were included. All patients underwent an optometric examination. The measurement of strabismus in distance vision was performed with the best optical correction using the APCT and the VOG GazeLab. Subjects were divided according to the type of strabismus; 41 were esotropic and 46 were exotropic.

RESULTS

The general comparison of APCT and VOG showed a mean difference of 0.60±2.74 prism diopters (Δ), not observing statistical differences between both methods ( P =0.059) and presenting a correlation of 0.976 ( P <0.001). Using APCT, the mean amount of esotropia for the group was 18.31±11.64 Δ and that of exotropia was 19.62±8.80 Δ. Compared with the VOG, the mean value of esotropia for the group was 18.65±11.65 Δ and that of exotropia was 19.48±8.62 Δ. The means are statistically different for the esotropia group ( P =0.005) but not for the exotropia group ( P =0.318). There was a high direct correlation between the methods of measurement for both the esotropic ( R =0.980; P <0.001) and exotropic patients ( R =0.975; P <0.001). Bland-Altman analysis shows a mean difference of 1.37±2.76 Δ for the esotropia patients and 0.31±2.66 Δ for the exotropic patients, respectively.

CONCLUSIONS

This study demonstrated comparable results in measuring strabismus between VOG and APTC for esotropia and exotropia, with an excellent correlation between both methods and good agreement, especially in subjects with exotropia.

Preliminary data on a novel smart glasses system for measuring the angle of deviation in strabismus

BACKGROUND/OBJECTIVES

To propose a novel smart glasses device for recording eye movement and compare its results to the prism alternate cover test (PACT).

SUBJECTS/METHODS

This method comparison study enrolled patients with strabismic conditions, who first underwent conventional strabismus evaluations (PACT in the primary position), followed by the smart glasses NeuroSpeed system (NSS) recording protocols. The video recordings were analysed using specialized software, to calculate the horizontal deviation from the primary position. The results were compared with those of the PACT using Passing‒Bablok regression and Bland‒Altman analysis.

RESULTS

This study included 70 individuals aged 4 to 80 years, of which 38 were men and 32 were women. The overall analysis of horizontal deviations using the Passing‒Bablok regression revealed a correlation coefficient (r) of 0.969, with a systemic bias of 0.00, a proportional bias of 0.809, and a perpendicular residual standard deviation of 4.134.

CONCLUSIONS

The predictive values of eye movement examinations recorded by the NSS were comparable to those of the PACT. Thus, this new system can provide additional information for ophthalmologists to aid in the diagnosis and measurement of strabismus.

Design and assessment of amblyopia, strabismus, and myopia treatment and vision training using virtual reality

Background

Virtual reality is a relatively new intervention that has the potential to be used in the treatment of eye and vision problems. This article reviews the use of virtual reality-related interventions in amblyopia, strabismus, and myopia research.

Methods

Sources covered in the review included 48 peer-reviewed research published between January 2000 and January 2023 from five electronic databases (ACM Digital Library, IEEE Xplore, PubMed, ScienceDirect and Web of Science). To prevent any missing relevant articles, the keywords, and terms used in the search included "VR", "virtual reality", "amblyopia", "strabismus," and "myopia". Quality assessment and data extraction were performed independently by two authors to form a narrative synthesis to summarize findings from the included research.

Results

Total number of 48 references were reviewed. There were 31 studies published on amblyopia, 18 on strabismus, and 6 on myopia, with 7 studies overlapping amblyopia and strabismus. In terms of technology, smartphone-based virtual reality headset viewers were utilized more often in amblyopia research, but commercial standalone virtual reality headsets were used more frequently in myopia and strabismus-related research. The software and virtual environment were mostly developed based on vision therapy and dichoptic training paradigms.

Conclusion

It has been suggested that virtual reality technology offers a potentially effective tool for amblyopia, strabismus, and myopia studies. Nonetheless, a variety of factors, especially the virtual environment and systems employed in the data presented, must be explored before determining whether virtual reality can be effectively applied in clinical settings. This review is significant as the technology in virtual reality software and application design features have been investigated and considered for future reference.

Virtual Reality and Augmented Reality- Emerging Screening and Diagnostic Techniques in Ophthalmology: a Systematic Review

In healthcare, virtual reality (VR) and augmented reality (AR) have been applied extensively for many purposes. Similar to other technologies such as telemedicine and artificial intelligence, VR and AR may improve clinical diagnosis and screening services in ophthalmology by alleviating current problems, including workforce shortage, diagnostic error, and underdiagnosis. In the past decade a number of studies and products have used VR and AR concepts to build clinical tests for ophthalmology, but comprehensive reviews on these studies are limited. Therefore, we conducted a systematic review on the use of VR and AR as a diagnostic and screening tool in ophthalmology. We identified 26 studies that implemented a variety of VR and AR tests on different conditions, including VR cover tests for binocular vision disorder, VR perimetry for glaucoma, and AR slit lamp biomicroscopy for retinal diseases. In general, while VR and AR tools can become standardized, automated, and cost-effective tests with good user experience, several weaknesses, including unsatisfactory accuracy, weak validation, and hardware limitations, have prevented these VR and AR tools from having wider clinical application. Also, a comparison between VR and AR is made to explain why studies have predominantly used VR rather than AR.