The worse eye revisited: Evaluating the impact of asymmetric peripheral vision loss on everyday function

Effect of Nonoverlapping Visual Field Defects on Vision-related Quality of Life in Glaucoma

PURPOSE

Glaucoma patients may be considered to have normal vision as long as each point of visual space is perceived by at least 1 eye, that is, with an intact binocular visual field (VF). We aimed to investigate the effect of nonoverlapping VF defects on vision-related quality of life (VR-QoL) in glaucoma.

DESIGN

Cross-sectional study.

SUBJECTS AND CONTROLS

Two hundred sixty-nine glaucoma patients and 113 controls.

METHODS

We evaluated VR-QoL of glaucoma patients (n = 269) and controls (n = 113) using 4 different questionnaires (National Eye Institute visual function questionnaire [NEI-VFQ-25], NEI-VFQ neuro-ophthalmology supplement, Glaucoma Quality of Life-15, and a luminance-specific questionnaire). We defined "differential VF" (DVF) as a measure of location-specific differences in the VFs of both eyes. Within the group of glaucoma patients, we analyzed the relationship between different aspects of VR-QoL and DVF using ordinal multiple regression analysis. Analyses were adjusted for age, sex, integrated VF (IVF; an estimate of the binocular VF from the monocular VFs), and higher visual acuity of both eyes, and corrected for multiple hypothesis testing.

MAIN OUTCOME MEASURES

Vision-related quality of life.

RESULTS

Glaucoma patients had lower VR-QoL than controls. Among the glaucoma patients, DVF was significantly associated with general vision (odds ratio [OR], 0.69; 95% confidence interval [CI], 0.54-0.89), peripheral vision (OR, 0.68; 95% CI, 0.54-0.86), walking on uneven ground (OR, 0.73; 95% CI, 0.58-0.93), crossing the street (OR, 0.61; 95% CI, 0.46-0.83), seeing other road users coming from the side (OR, 0.67; 95% CI, 0.52-0.85), cycling during the day (OR, 0.64; 95% CI, 0.46-0.89) and seeing outside on a sunny day (OR, 0.73; 95% CI, 0.57-0.94). In general, IVF was a stronger predictor of VR-QoL than DVF.

CONCLUSIONS

Nonoverlapping VF defects affect VR-QoL. Although IVF is strongly associated with VR-QoL, basing clinical decisions only on IVF leads to overlooking vision problems that patients may have.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Assessing REALTER simulator: analysis of ocular movements in simulated low-vision conditions with extended reality technology

Immersive technology, such as extended reality, holds promise as a tool for educating ophthalmologists about the effects of low vision and for enhancing visual rehabilitation protocols. However, immersive simulators have not been evaluated for their ability to induce changes in the oculomotor system, which is crucial for understanding the visual experiences of visually impaired individuals. This study aimed to assess the REALTER (Wearable Egocentric Altered Reality Simulator) system's capacity to induce specific alterations in healthy individuals' oculomotor systems under simulated low-vision conditions. We examined task performance, eye movements, and head movements in healthy participants across various simulated scenarios. Our findings suggest that REALTER can effectively elicit behaviors in healthy individuals resembling those observed in individuals with low vision. Participants with simulated binocular maculopathy demonstrated unstable fixations and a high frequency of wide saccades. Individuals with simulated homonymous hemianopsia showed a tendency to maintain a fixed head position while executing wide saccades to survey their surroundings. Simulation of tubular vision resulted in a significant reduction in saccade amplitudes. REALTER holds promise as both a training tool for ophthalmologists and a research instrument for studying low vision conditions. The simulator has the potential to enhance ophthalmologists' comprehension of the limitations imposed by visual disabilities, thereby facilitating the development of new rehabilitation protocols.

A systematic review of extended reality (XR) for understanding and augmenting vision loss

Over the past decade, extended reality (XR) has emerged as an assistive technology not only to augment residual vision of people losing their sight but also to study the rudimentary vision restored to blind people by a visual neuroprosthesis. A defining quality of these XR technologies is their ability to update the stimulus based on the user's eye, head, or body movements. To make the best use of these emerging technologies, it is valuable and timely to understand the state of this research and identify any shortcomings that are present. Here we present a systematic literature review of 227 publications from 106 different venues assessing the potential of XR technology to further visual accessibility. In contrast to other reviews, we sample studies from multiple scientific disciplines, focus on technology that augments a person's residual vision, and require studies to feature a quantitative evaluation with appropriate end users. We summarize prominent findings from different XR research areas, show how the landscape has changed over the past decade, and identify scientific gaps in the literature. Specifically, we highlight the need for real-world validation, the broadening of end-user participation, and a more nuanced understanding of the usability of different XR-based accessibility aids.

Quality of life in patients with glaucoma assessed by 39-item National Eye Institute Visual Functioning Questionnaire (NEI VFQ-39)

PURPOSE

The purpose of the study was to evaluate glaucoma patients' quality of life (QoL) as measured by National Eye Institute Visual Functioning Questionnaire (NEI VFQ-39) and to examine the influence of patient characteristics and disease stage measured by visual field loss on QoL.

METHODS

A prospective survey of patients with an established diagnosis of glaucoma without concomitant eye disease was conducted. Patients completed a validated German translation of the NEI VFQ-39 questionnaire. Visual field defects were graded using simplified Hodapp's classification. VFQ-39 scores were compared between groups.

RESULTS

We included 60 patients, 28 of whom were classified as early, 16 as moderate, and 16 as advanced stage glaucoma. No differences were found in sex, visual acuity of the better eye, near visual acuity, treatment type, and VFQ rating for "General health" between groups. In the advanced group, VFQ-39 (p = 0.01) and VFQ-25 (p = 0.01) composite scores were significantly lower than in the early group. In addition, distance visual acuity (worse eye) was significantly worse in the advanced than in early stage patients (p = 0.04, Table 4). Patients with advanced glaucoma had significantly lower VFQ-39 subscale scores for "General vision" (p = 0.023), "Near activities" (p = 0.02), "Distance activities" (p = 0.003), "Mental health" (p = 0.008), "Driving" (p = 0.011), and "Peripheral vision" (p = 0.017) than early glaucoma patients. Patients with moderate glaucoma had significantly lower scores for "Distance activities" (p = 0.028) than early stage glaucoma patients. VFI (better eye: r = 0.65, worse eye: r = 0.5) and MD (better eye: r = 0.6, worse eye: r = 0.49) were significantly (p < 0.001) correlated with VFQ-39. Correlations of VFQ-39 with age, VFI intereye difference, distance, or near visual acuity were not significant.

CONCLUSION

Compared to patients with early glaucoma, patients with moderate stage glaucoma reported higher difficulty with distance activities (e.g. navigating an urban environment, watching television). Patients with advanced stage glaucoma reported lower VFQ-39 composite and subscale scores relevant to topics of general vision complaints, difficulties with near work and finding things, navigating urban outdoor environments, and watching television; worries and frustrations with vision difficulties; and difficulty driving and noticing objects off to the side of footpaths. Visual field indices MD and VFI were strongly correlated with QoL as assessed by VFQ-39. VA was not correlated with QoL. In patients with moderate or advanced glaucoma, QoL may be significantly impacted by glaucomatous visual field defects even when visual acuity is preserved.

Applications of augmented reality in ophthalmology [Invited]

Throughout the last decade, augmented reality (AR) head-mounted displays (HMDs) have gradually become a substantial part of modern life, with increasing applications ranging from gaming and driver assistance to medical training. Owing to the tremendous progress in miniaturized displays, cameras, and sensors, HMDs are now used for the diagnosis, treatment, and follow-up of several eye diseases. In this review, we discuss the current state-of-the-art as well as potential uses of AR in ophthalmology. This review includes the following topics: (i) underlying optical technologies, displays and trackers, holography, and adaptive optics; (ii) accommodation, 3D vision, and related problems such as presbyopia, amblyopia, strabismus, and refractive errors; (iii) AR technologies in lens and corneal disorders, in particular cataract and keratoconus; (iv) AR technologies in retinal disorders including age-related macular degeneration (AMD), glaucoma, color blindness, and vision simulators developed for other types of low-vision patients.

Effects of Transient Loss of Vision on Head and Eye Movements during Visual Search in a Virtual Environment

Central and peripheral fields of view extract information of different quality and serve different roles during visual tasks. Past research has studied this dichotomy on-screen in conditions remote from natural situations where the scene would be omnidirectional and the entire field of view could be of use. In this study, we had participants looking for objects in simulated everyday rooms in virtual reality. By implementing a gaze-contingent protocol we masked central or peripheral vision (masks of 6 deg. of radius) during trials. We analyzed the impact of vision loss on visuo-motor variables related to fixation (duration) and saccades (amplitude and relative directions). An important novelty is that we segregated eye, head and the general gaze movements in our analyses. Additionally, we studied these measures after separating trials into two search phases (scanning and verification). Our results generally replicate past on-screen literature and teach about the role of eye and head movements. We showed that the scanning phase is dominated by short fixations and long saccades to explore, and the verification phase by long fixations and short saccades to analyze. One finding indicates that eye movements are strongly driven by visual stimulation, while head movements serve a higher behavioral goal of exploring omnidirectional scenes. Moreover, losing central vision has a smaller impact than reported on-screen, hinting at the importance of peripheral scene processing for visual search with an extended field of view. Our findings provide more information concerning how knowledge gathered on-screen may transfer to more natural conditions, and attest to the experimental usefulness of eye tracking in virtual reality.

Seeing other perspectives: evaluating the use of virtual and augmented reality to simulate visual impairments (OpenVisSim)

Simulations of visual impairment are used to educate and inform the public. However, evidence regarding their accuracy remains lacking. Here we evaluated the effectiveness of modern digital technologies to simulate the everyday difficulties caused by glaucoma. 23 normally sighted adults performed two everyday tasks that glaucoma patients often report difficulties with: a visual search task in which participants attempted to locate a mobile phone in virtual domestic environments (virtual reality (VR)), and a visual mobility task in which participants navigated a physical, room-scale environment, while impairments were overlaid using augmented reality (AR). On some trials, a gaze-contingent simulated scotoma-generated using perimetric data from a real patient with advanced glaucoma-was presented in either the superior or inferior hemifield. The main outcome measure was task completion time. Eye and head movements were also tracked and used to assess individual differences in looking behaviors. The results showed that the simulated impairments substantially impaired performance in both the VR (visual search) and AR (visual mobility) tasks (both P < 0.001). Furthermore, and in line with previous patient data: impairments were greatest when the simulated Visual Field Loss (VFL) was inferior versus superior (P < 0.001), participants made more eye and head movements in the inferior VFL condition (P < 0.001), and participants rated the inferior VFL condition as more difficult (P < 0.001). Notably, the difference in performance between the inferior and superior conditions was almost as great as the difference between a superior VFL and no impairment at all (VR: 71%; AR: 70%). We conclude that modern digital simulators are able to replicate and objectively quantify some of the key everyday difficulties associated with visual impairments. Advantages, limitations, and possible applications of current technologies are discussed. Instructions are also given for how to freely obtain the software described (OpenVisSim).