Factors related to the use of a head-mounted display for individuals with low vision

Performance on clinical outcomes, activities of daily living and user experience on head-mounted displays for people with vision impairment

PURPOSE

To compare the objective performance, acceptance and usability of head-mounted displays (HMDs) to provide evidence-based data that could be used to increase the efficiency of device referrals based upon a person's vision loss and functional needs.

METHODS

A cross-sectional, counterbalanced, individually controlled crossover study was performed on 15 adults with various eye conditions. Performance was measured when using four HMDs: eSight4, Eyedaptic EYE3, Eyedaptic EYE4 and IrisVision Inspire. Performance on clinical visual acuity tests and contrast were assessed, as well as vision-related activities of daily living (ADL) which were divided into three categories: Reading, Searching & Identifying and Eye-hand Coordination. User-experience was also assessed. Logistic regression analyses, Friedman one-way repeated measure analyses of variance by ranks and multivariate permutation testing were used for analysis.

RESULTS

There was a significant improvement in visual acuity when using all devices. For contrast tasks, only the eSight4 and Eyedaptic EYE3 improved performance relative to baseline. For most Reading and Searching & Identifying tasks, the odds of being able to perform the tasks were significantly higher while using the devices. However, the actual performance with most devices (e.g., number of words read or reading speed) did not improve significantly over baseline for most tasks. For the Eye-hand Coordination tasks, participants performed equivalent to or significantly poorer than baseline when using the devices. No demographic or clinical predictors of outcomes were identified. Participants expressed dissatisfaction with the devices' effectiveness, acceptability and usability.

CONCLUSIONS

While performance on clinical tests was better when using the devices, performance on most real-world ADLs was equal to or worse than baseline. No single device improved performance on all tasks, and performance on any one task was not improved with all the devices. The overall dissatisfaction with the devices paralleled the lack of objective improvement in the performance of real-world tasks.

Comparative effectiveness between two types of head-mounted magnification modes using a smartphone-based virtual display

SIGNIFICANCE

This work shows the benefits of using two different magnification strategies to improve the reading ability of low-vision patients using a head-mounted technology.

PURPOSE

The aim of this study was to conduct a comparative clinical trial evaluating the effectiveness of two magnification strategies in a head-mounted virtual reality display.

METHODS

Eighty-eight eligible low-vision subjects were randomized into two arms: (1) the full-field magnification display or (2) the virtual bioptic telescope mode. Subjects completed baseline testing and received training on how to use the device properly and then took the device home for a 2- to 4-week intervention period. An adaptive rating scale questionnaire (Activity Inventory) was administered before and after the intervention (home trial) period to measure the effect of the system. A Simulator Sickness Questionnaire was also administered. Baseline and follow-up results were analyzed using Rasch analysis to assess overall effectiveness of each magnification mode for various functional domain categories.

RESULTS

Both magnification modes showed a positive effect for reading, visual information, and the overall goals functional domain categories, with only reading reaching statistical significance after correction for multiple comparisons. However, there were no significant between-group differences between the two modes. The results of the Simulator Sickness Questionnaire showed that the magnification modes of the head-mounted display device were overall well tolerated among low-vision users.

CONCLUSIONS

Both the full-field and virtual bioptic magnification strategies were effective in significantly improving functional vision outcomes for self-reported reading ability.

Evaluation of a Retinal Projection Laser Eyeware in Patients with Visual Impairment Caused by Corneal Diseases in a Randomized Trial

PURPOSE

Patients with incurable corneal diseases experience visual impairment (VI) despite having a healthy retina and optic pathway. Low-vision aids (LVAs) can optimize the use of remaining vision through magnification and contrast enhancement, but do not harness the full visual capacity because they rely on the optic media. Therefore, we investigated a novel laser eyewear (LEW) technology that bypasses the anterior segment of the eye. Images captured by an integrated camera are projected directly onto the retina using a low-energy laser. The patient is able to view a full-color video, realized as augmented reality. We aimed to evaluate the efficacy of the LEW to enhance the vision of individuals with corneal diseases.

DESIGN

Prospective, randomized, crossover clinical trial.

PARTICIPANTS

We examined the retinal projection glasses in 21 patients (25-69 years) with VI (0.7 logarithm of the minimum angle of resolution [logMAR] or worse) resulting from corneal diseases. Patients with comorbidities that impact vision, such as retinal disorders, were excluded.

METHODS

Standardized measurements of visual acuity (VA) for near vision (NV) and distance vision (DV) were conducted using ETDRS charts with the respective best correction (BC) and then with LEW. In addition reading speed, vision-related quality of life (QoL) and capacity to carry out daily tasks were assessed at an initial visit and at 2 subsequent visits after a home phase with and without the device. Six weeks after last use of the LEW, an ophthalmologic examination including spectral-domain-OCT or full-field-electroretinography was conducted and compared with baseline findings to evaluate the safety of the device. Four patients participated and completed a subsequent 12-month follow-up phase.

MAIN OUTCOME MEASURES

Improvement of VA using the LEW. Secondary objectives included safety, reading speed, QoL, and usability in daily activities.

RESULTS

The mean VA in patients with VI was improved by 0.43 logMAR in DV using the LEW compared with BC (P < 0.0001). Using the ×2 magnification mode of the LEW resulted in an average improvement of 0.66 logMAR compared with BC (P < 0.0001). In NV, an increase of 0.47 logMAR was achieved compared with BC (P < 0.0001). Although only 4 of 21 participants were able to read with BC, 17 of 21 participants were able to read with the LEW. Quality of life significantly improved in the 17 participants who completed all visits.

CONCLUSIONS

We demonstrated that the retinal projection glasses resulted in enhanced VA for all participants by directly projecting images onto the intact retina. In future, the LEW could represent a new option as an LVA for patients with corneal diseases. No pathological alterations were observed in the safety assessments.

FINANCIAL DISCLOSURE(S)

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

At-Home Trial of Four Different Head-Mounted Displays in Visual Rehabilitation of People with Stargardt Disease

Purpose

To examine the potential of different head-mounted displays in the rehabilitation of individuals with visual impairment.

Methods

This prospective explorative study conducted between September 2019 and August 2020 included participants with Stargardt disease with moderate to severe visual impairment and a relatively preserved peripheral visual field. AceSight, eSight 3, IrisVision Live, and Jordy were tested. After instruction and training, participants chose two head-mounted displays for home use for two weeks per device. The Canadian Occupational Performance Measure was used for evaluation.

Results

Twelve participants (aged 16-53 years) tested all head-mounted displays in the clinic. Distance visual acuity and reading distance improved with all head-mounted displays and eSight and Irisvision improved near visual acuity. Six participants decided not to test the head-mounted display at home due to lack of time or energy, dizziness and discomfort, double vision and peripheral visual field limitation, or aesthetics. After home use, the participants reported improved visual function at a distance with IrisVision, AceSight, and e-Sight, whereas only AceSight improved vision during near tasks. IrisVision and eSight improved reading ability, and none of the devices improved vision during tasks involving computers. Five participants used the devices sparingly, and five avoided public use owing to aesthetics.

Conclusion

We found an improvement in distance visual acuity and increased reading distance for all tested head-mounted displays. Additionally, IrisVision and eSight improved visual function at near and eSight also improved contrast vision at distance. Despite the possibility of improving vision, social stigma and device aesthetics kept the participants from using head-mounted displays in public and limited their use at home.

"I'm like something out of star wars": a qualitative investigation of the views of people with age-related macular degeneration regarding wearable electronic vision enhancement systems

PURPOSE

This study explores the initial views of people with age-related macular degeneration towards wearable electronic vision enhancement systems.

METHODS

Ten adults with age-related macular degeneration participated in semi-structured interviews, which were analysed using reflexive thematic analysis.

RESULTS

Four themes were identified. Firstly, participants spoke of the wide-ranging impact of sight loss and how current helpful coping strategies still had significant limitations, affecting their desire to seek new solutions. The second theme showed that "other people" offered welcomed support with existing electronic coping solutions and are needed to provide suitable advice and training. However, "other people" limited the acceptability of using new solutions in public places. The third theme captured participants' desire for a wearable aid providing image magnification and enhancement over a range of distances. The final theme covered the reality of some current wearable technology, perceived as heavy, enclosing, or strange in appearance. Appearance caused some to lose interest in use, although others reframed the devices' desired usefulness to solo and sedentary activities.

CONCLUSION

This population are interested in the potential benefits of wearable electronic vision enhancement systems. More work is needed to understand the suitability of current solutions due to participant concerns about training, appearance and performance.

Low vision devices for age-related macular degeneration: a systematic review

PURPOSE

Age-related macular degeneration (AMD) is a degenerative condition impacting central vision. Evaluating the effectiveness of low vision devices provides empirical evidence on how devices can rehabilitate and overcome deficits caused by AMD. This evidence could help to facilitate discussion on necessary future improvements to vision enhancement technology.

METHODS

A systematic review of the literature was conducted on low vision device use in AMD populations. Relevant peer-reviewed research articles from six databases were screened.

RESULTS

The findings of thirty-five studies revealed a significant positive impact of low vision devices leading to improvements in visual acuity, reading performance, facial recognition, and more. While the studies were found to have moderate risks of bias, a GRADE assessment of the evidence suggested the certainty of the evidence was low-moderate.

DISCUSSION

Simple hand-held low vision devices (e.g., magnifiers) appear to currently have greater preferential support than newer visual enhancement technology (e.g., head mounted devices). Financial, comfort or usability reasons may influence preferences more than performance-based findings. However, there is a lack of studies examining newer technologies in AMD populations, which future research should address. Moreover, given the presence of bias across the studies and limited controlled experiments, confidence in the results may be low.

CONCLUSIONS

Most studies indicated that low vision devices have positive impacts on reading and visual performance. But, even though they are reported to be a valuable asset to AMD populations, more rigorous research is required to draw conclusive evidence. IMPLICATIONS FOR REHABILITATIONLow vision devices can improve patient outcomes (e.g., vision, reading ability) for age-related macular degeneration populations.A multidisciplinary combination of low vision devices and rehabilitative services (i.e., eccentric viewing training, counselling, education) may enhance quality of life.

Are wearable electronic vision enhancement systems (wEVES) beneficial for people with age-related macular degeneration? A scoping review

INTRODUCTION

Age-related macular degeneration (AMD) is the most common cause of irreversible visual impairment in the United Kingdom. It has a wide-ranging detrimental impact on daily living, including impairment of functional ability and quality of life. Assistive technology designed to overcome this impairment includes wearable electronic vision enhancement systems (wEVES). This scoping review assesses the usefulness of these systems for people with AMD.

METHODS

Four databases (Cumulative Index to Nursing and Allied Health Literature, PubMed, Web of Science and Cochrane CENTRAL) were searched to identify papers that investigated image enhancement with a head-mounted electronic device on a sample population that included people with AMD.

RESULTS

Thirty-two papers were included: 18 studied the clinical and functional benefits of wEVES, 11 investigated use and usability and 3 discussed sickness and adverse effects.

CONCLUSIONS

Wearable electronic vision enhancement systems provide hands-free magnification and image enhancement producing significant improvements in acuity, contrast sensitivity and aspects of laboratory-simulated daily activity. Adverse effects were infrequent, minor and spontaneously resolved with the removal of the device. However, when symptoms arose, they sometimes persisted with continued device usage. There are multi-factorial influences and a diversity of user opinions on promotors to successful device use. These factors are not exclusively driven by visual improvement and incorporate other issues including device weight, ease of use and inconspicuous design. There is insufficient evidence of any cost-benefit analysis for wEVES. However, it has been shown that a user's decision to make a purchase evolves over time, with their estimates of cost falling below the retail price of the devices. Additional research is needed to understand the specific and distinct benefits of wEVES for people with AMD. Further patient-centred research should assess the benefits of wEVES in user-led activities when directly compared with alternative coping strategies, allowing professionals and users to make better prescribing and purchasing decisions.

Design of Smart Head–Mounted Display Technology: A Convergent Mixed-Methods Study

Introduction: The purpose of this study was to characterize functional impairments and human factor considerations that affect perceptions and preferences for head-mounted display (HMD) technology for adults with low vision and chronic eye disease. Methods: Through a convergent mixed-methods design, participants with visual impairments (age-related macular degeneration, diabetic retinopathy, glaucoma, or retinitis pigmentosa) were recruited. Participants completed the Impact of Vision Impairment (IVI) questionnaire, used commercially available HMDs (eSight, NuEyes, and Epson Moverio), and were interviewed. The IVI was used to identify groups with low, moderate, and high vision–related quality of life (VRQOL). Transcribed interviews were analyzed using a thematic approach. The survey and qualitative findings were integrated using mixed-methods joint display analysis. Results: Twenty-one participants were enrolled (mean age of 58.2 years, 57% male, median Snellen acuity of 20/40 [range: 20/20–hand movement]). An equal number ( n = 9) expressed a preference for eSight and NuEyes, while ( n = 3) preferred the Moverio. Participants emphasized ease of use, including HMD controls and screen, as common reasons for preference. Those with lower IVI well-being scores preferred eSight due to vision improvement. Those with moderate IVI well-being scores preferred NuEyes due to comfort and size. Those with high IVI well-being scores cited usability as the most important feature. Discussion: User preferences for HMD features were associated with VRQOL. A mixed-methods approach explained how varying degrees of visual impairment and HMD preferences were qualitatively related to usability at the individual level. Implications for Practitioners: To increase acceptance, new HMD development for low vision should focus on performance, usability, and human factors engineering. Although HMD technology can benefit individuals with low vision, device features and functions vary in meaningful ways based on vision parameters. Practitioners should be aware of how patient and device variations influence preferences when they recommend wearable systems and optimize training to harness these systems.

Shopping When You Are Deafblind: A Pre-Technology Test of New Methods for Face-to-Face Communication—Deafblindness and Face-to-Face Communication

This article presents the first-year results of a project that aimed to explore the feasibility of using a braille display and a smartphone in society to improve face-to-face communication for a person living with deafblindness, using a simulated communication situation. An applied experimental development design was implemented, followed by a pre-test in the community. Two clinicians and an engineer conducted communication tests with three communication partners with normal vision in a shopping mall. A blind clinician acting as deafblind bought an iPhone case and asked for the location of two stores. Communication partners did not report any difficulties, understood the exchanges, and were proud to have helped a person living with deafblindness. No communication breakdowns or keyboard input incidents occurred. Speech turns were not optimal but can be improved. Clinicians proposed a sequence of three training modules: (1) prior knowledge (basic operations for iPhone, software, and braille display), (2) methods for preparing a face-to-face discussion, and (3) processes during a face-to-face discussion. Results demonstrate the feasibility of using a tactile technological solution coupled with a smartphone to interact with unknown interlocutors. Technology trials form the groundwork for a 9-month case study, involving two individuals with deafblindness.

Simulating Macular Degeneration to Investigate Activities of Daily Living: A Systematic Review

Purpose: Investigating difficulties during activities of daily living is a fundamental first step for the development of vision-related intervention and rehabilitation strategies. One way to do this is through visual impairment simulations. The aim of this review is to synthesize and assess the types of simulation methods that have been used to simulate age-related macular degeneration (AMD) in normally sighted participants, during activities of daily living (e.g., reading, cleaning, and cooking).

Methods: We conducted a systematic literature search in five databases and a critical analysis of the advantages and disadvantages of various AMD simulation methods (following PRISMA guidelines). The review focuses on the suitability of each method for investigating activities of daily living, an assessment of clinical validation procedures, and an evaluation of the adaptation periods for participants.

Results: Nineteen studies met the criteria for inclusion. Contact lenses, computer manipulations, gaze contingent displays, and simulation glasses were the main forms of AMD simulation identified. The use of validation and adaptation procedures were reported in approximately two-thirds and half of studies, respectively.

Conclusions: Synthesis of the methodology demonstrated that the choice of simulation has been, and should continue to be, guided by the nature of the study. While simulations may never completely replicate vision loss experienced during AMD, consistency in simulation methodology is critical for generating realistic behavioral responses under vision impairment simulation and limiting the influence of confounding factors. Researchers could also come to a consensus regarding the length and form of adaptation by exploring what is an adequate amount of time and type of training required to acclimatize participants to vision impairment simulations.

Head-mounted Visual Assistive Technology-related Quality of Life Changes after Telerehabilitation

SIGNIFICANCE

Head-mounted low vision devices have become a viable alternative to enhance residual vision. This study supports the use of a head-mounted display to improve aspects of functional vision and quality of life. Much is still unknown regarding the required frequency, duration, or potential effectiveness of this telerehabilitation training protocol or what characteristics best identify optimal users.

PURPOSE

A randomized study explored the effect of telerehabilitation on quality of life and functional vision in individuals with low vision using a head-mounted display.

METHODS

We recruited 57 participants (age, 21 to 82 years; mean, 54.5 years) among new prospective eSight Eyewear users, randomized 1:1 into two parallel groups; the experimental group received the telerehabilitation training provided by a low vision therapist, whereas the control group received the self-training standard offered by the device manufacturer and without involvement of a low vision therapist. The primary outcome measures were the impact of telerehabilitation on validated measures of assistive technology-related quality of life: the Psychosocial Impact of Assistive Devices Scale and the Quebec User Evaluation of Satisfaction with Assistive Technology scale. Exploratory outcomes were the assessment of self-reported functional vision using the Veterans Affairs Low Vision Visual Functioning Questionnaire-48 and cybersickness associated with head-mounted display use with the Simulator Sickness Questionnaire.

RESULTS

Assistive technology-related quality of life was improved when measured by the satisfaction scale but not the psychosocial scale within the first 3 months, independently of training type. Overall, functional vision improvement was observed within the first 2 weeks of device use and maintained during the 6-month study, independently of group type. Cybersickness outcomes were similar between training groups and did not change significantly for 6 months.

CONCLUSIONS

eSight Eyewear, either with telerehabilitation or with the manufacturer self-training comparison, improved functional vision and increased users' quality of life within the initial 3 months of device training and practice.

Personalized Telerehabilitation for a Head-mounted Low Vision Aid: A Randomized Feasibility Study

SIGNIFICANCE

A recent trend in low vision rehabilitation has been the use of portable head-mounted displays to enhance residual vision. Our study confirms the feasibility of telerehabilitation and informs the development of evidence-based recommendations to improve telerehabilitation interventions to reduce device abandonment.

PURPOSE

To develop evidence-based recommendations for telerehabilitation, we conducted a feasibility study in preparation for a future randomized trial on the use of head-mounted displays.

METHODS

We recruited novice eSight Eyewear users, randomized 1:1: the experimental group received telerehabilitation by a low vision therapist using video conferencing; the control group completed at home self-training provided by the device manufacturer. The primary feasibility outcomes were whether the recruitment goal of 60 participants (30/group) was attainable within 1 year and how participants judged the accessibility and acceptability of the telerehabilitation. An exploratory outcome was the impact of telerehabilitation on eSight Eyewear use behavior.

RESULTS

Among 333 eSight users, 57 participants were enrolled, of which 35% withdrew from the study, whereas the remainder completed the 6-month follow-up. The withdrawal rate was higher in the control group but did not differ significantly from the experimental group. High accessibility (93% of participants accessed the platform) and global acceptability (100% overall satisfaction) were reported among those who completed the telerehabilitation protocol. The therapist had no difficulty judging the participants' reading performances qualitatively while participants used their device to read their eSkills and VisExc guides. Most participants improved their daily activities, based on qualitative reports of the attained goals. Seventy-nine percent of individuals declined to participate, whereas 16% of participants decided not to use eSight Eyewear anymore.

CONCLUSIONS

The data demonstrated the feasibility of a randomized controlled telerehabilitation study for people with low vision using a head-mounted display. Positive feedback from the participants and the therapist suggests the potential value of this modality for low vision services.

Device abandonment in deafblindness: a scoping review of the intersection of functionality and usability through the International Classification of Functioning, Disability and Health lens

OBJECTIVES

Abandonment of vision, hearing or mobility aids suggests common barriers and facilitators to ongoing device use. However, the possible interactive effects of combined hearing and vision disabilities on device use by those living with deafblindness are unclear. Here we summarise existing knowledge on variables influencing assistive technology use from the perspective of persons living with deafblindness. We used the WHO's International Classification of Functioning, Disability and Health (ICF) framework to contextualise the findings, asking 'What is currently known about variables influencing the (non-)use of assistive devices recommended for persons with deafblindness?'

DESIGN

A scoping review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews Checklist.

DATA SOURCES

PubMed; ProQuest: ERIC; ProQuest Dissertation; ProQuest: Sociological Thesaurus; Web of Science; Scientific Electronic Library Online; Bielefeld Academic Search Engine; Pascal & Francis; APA PsycINFO and Ebsco for CINAHL were searched through 9 November 2020.

ELIGIBILITY CRITERIA

We included peer-reviewed studies that reported on assistive technology, device abandonment/utilisation and provided data from persons living with deafblindness.

DATA EXTRACTION AND SYNTHESIS

Four team members independently scored 83 studies for eligibility.

RESULTS

Ten articles were chosen for data extraction. The emerging variables replicated established categories of barriers and facilitators: personal, device-related, environmental and intervention variables. The use of the ICF highlighted how an intermediate variable (eg, device acceptability) was necessary in order for a variable to become a barrier or a facilitator to device use.

CONCLUSIONS

The variables influencing device use by persons with deafblindness followed the same categories described for single impairments. Usability was challenged in devices that rely on the 'other' sense. Haptic and tactile aids are rarely studied. The limited available information and the dire need for assistive technologies for people with deafblindness emphasises the urgency of research and technology development for this marginalised population.

Measuring changes in device use of a head-mounted low vision aid after personalised telerehabilitation: protocol for a feasibility study

INTRODUCTION

A recent trend in low vision (LV) has been towards the use of portable head-mounted displays (HMDs) to enhance residual vision. The decision process around the (non-)use of such devices have been identified as multifactorial. Among important barriers identified in the context of magnifying LV aids were transportation issues and insufficient training. In recent years, telerehabilitation has become of growing interest in healthcare because it allows individuals to remain at home while receiving rehabilitation services. A recent pilot study indicated encouraging outcomes; however, very few applications of telerehabilitation for LV have been tested systematically.

METHODS AND ANALYSIS

To help guide evidence-based practice recommendations for this modality, we will carry out a feasibility study to assess the recruitment, retention, accessibility and acceptability of an eventual fully randomised trial of telerehabilitation for people with LV using HMDs. We will recruit 60 participants aged 18+ years among prospective eSight Eyewear owners, randomised 1:1 into two parallel groups. The active intervention will be the telerehabilitation operated by a LV therapist; the control arm will be the current self-training standard provided by the device vendor. The primary feasibility outcome measures will be: time to recruit participants, loss to follow-up, accessibility and acceptability of the telerehabilitation (satisfaction of the users and LV therapist). Exploratory outcomes will be the impact of telerehabilitation on eSight Eyewear use behaviour (discontinuance rate), and validated measures of assistive-technology-related quality of life.

ETHICS AND DISSEMINATION

The study was approved by the Ethics Review Board of the Centre de Recherche Interdisciplinaire en Réadaptation de Montréal métropolitain (CRIR# 1286-1217). Dissemination is planned via local, national and international healthcare conferences and peer-reviewed journal publications.