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Auditory landmarks can contribute to spatial updating during navigation with vision. Whereas large inter-individual differences have been identified in how navigators combine auditory and visual landmarks, it is still unclear under what circumstances audition is used. Further, whether or not individuals optimally combine auditory cues with visual cues to decrease the amount of perceptual uncertainty, or variability, has not been well-documented. Here, we test audiovisual integration during spatial updating in a virtual navigation task. In Experiment 1, 24 individuals with normal sensory acuity completed a triangular homing task with either visual landmarks, auditory landmarks, or both. In addition, participants experienced a fourth condition with a covert spatial conflict where auditory landmarks were rotated relative to visual landmarks. Participants generally relied more on visual landmarks than auditory landmarks and were no more accurate with multisensory cues than with vision alone. In Experiment 2, a new group of 24 individuals completed the same task, but with simulated low vision in the form of a blur filter to increase visual uncertainty. Again, participants relied more on visual landmarks than auditory ones and no multisensory benefit occurred. Participants navigating with blur did not rely more on their hearing compared with the group that navigated with normal vision. These results support previous research showing that one sensory modality at a time may be sufficient for spatial updating, even under impaired viewing conditions. Future research could investigate task- and participant-specific factors that lead to different strategies of multisensory cue combination with auditory and visual cues.

Significance: Low vision is a public health priority disability condition. People with this condition face multiple types of discrimination in a society that is not accustomed to diversity., Purpose: This study aimed to describe the life experience of people with low vision from an intersectional perspective in Medellín, Colombia., Methods: A qualitative ethnographic case study was conducted, considering the intersectional perspective as an analytical element to comprehend the everyday experience of people with low vision. Twenty-nine interviews were conducted with 10 participants, along with 16 participant observation exercises in their daily lives, with prior informed consent., Results: Participants experienced discrimination due to their visual condition, which had negative implications for the development of their life projects. Three categories emerged: Discrimination in everyday contexts: ocularcentrism, gender challenges in the lives of people with low vision, and challenges in seeking vision rehabilitation services., Conclusions: The results of the study show that people experience discrimination, exclusion, and stigmatization in their daily activities, which vary according to the traditionally assigned roles of gender, social class, age, and educational level, among others. Given the complexity of the experience, it is important for health and visual rehabilitation professionals to broaden their perspective and transition toward vision rehabilitation models that address the various dimensions affected by this condition., Competing Interests: Conflict of Interest Disclosure: None of the authors have reported a financial conflict of interest., (Copyright © 2024 American Academy of Optometry.)

Purpose: Accurate objective assessment of visual acuity is crucial, particularly in cases of suspected malingering, or when the patient's inability to cooperate makes standard psychophysical acuity tests unreliable. The P300 component of the event-related potentials offers a potential solution and even allows for the use of standard optotypes like the Landolt C. However, low-vision patients with large eccentric visual field defects often struggle to locate the Landolt C gap quickly enough for a P300 to be reliably produced., Methods: Addressing this challenge, we introduce a novel optotype (the "FreiBurger") with a critical detail that extends through the optotype's center. Two experiments, with 16 and 12 participants, respectively, were conducted. In the first, psychophysical acuity estimates were obtained with both the FreiBurger and the Landolt C. In the second, we tested the performance of the FreiBurger, relative to the Landolt C, in eliciting a P300 with undegraded vision, simulated low vision, and in a simulated combination of low vision and visual field constriction., Results: Comparable psychophysical acuity values (average difference 0.03 logMAR) were obtained for both optotypes. In the P300 recordings, both optotypes produced similar P300 responses under conditions of undegraded vision and low vision. However, with the combination of low vision and constricted visual field, the P300 could only be reliably obtained with the FreiBurger, while the amplitude was drastically reduced with the Landolt C (9.1 µV vs. 2.2 µV; p < 0.0005)., Conclusion: The new optotype extends the applicability of P300-based acuity estimation to the frequently encountered combination of low vision and constricted visual field, where Landolt C optotypes fail. Although impairments were simulated in the present study, we assume that the advantages of the new optotype will also manifest in patients with such impairments. We furthermore expect the advantages to apply to time-sensitive psychophysical examinations as well., (© 2024. The Author(s).)

Background: Instrumental activities of daily living (IADL) are typically self-reported ability to perform complex tasks vital for independent living. There is a need for a complementary objective, performance-based approach especially in tracking outcomes in visual rehabilitation for patients with irreversible vision impairment ("low vision"). Our goals are: (1) To describe the validity of timed performance of instrumental activities of daily living (timed IADL or TIADL) tasks in individuals with irreversible vision impairment, by examining its association with visual function (visual acuity, contrast sensitivity, visual field), (2) To explore the correlation between TIADL and self-reported IADL., Methods: Twenty TIADL tasks were administered to 88 patients (median age 63.3 years, IQR 37.4-78.0) recruited from the UAB Department of Ophthalmology, Callahan Eye Hospital Clinics. An average Z-score incorporating time and accuracy of task completion was constructed. Minor accuracy errors were penalized 1 standard deviation from their calculated Z-score and major accuracy errors were assigned maximum allotted time. Linear regression was used to analyze the association between TIADL score and measured visual acuity (Early Treatment Diabetic Retinopathy Study, ETDRS chart), contrast sensitivity (Pelli-Robson), and binocular visual field (Esterman) with an unadjusted model and an adjusted model accounting for age, comorbidities, and depression scale (Center for Epidemiological Studies Depression, CES-D). Pearson correlation was used to estimate the correlation between TIADL and IADL., Results: Increased time to task completion was associated with decreased visual function. Each decreased line of ETDRS read was associated with an increase of 0.002 (95% CI 0.001, 0.002) Z-score (P < 0.01). A decreased ability to discern each Pelli-Robson letter was associated with an increase of 0.26 (95% CI 0.19, 0.33) Z-score (P < 0.01). For each less Esterman target identified, there was an increase of 0.01 (95% CI 0.003, 0.02) Z-score. Self-reported IADL and TIADL were correlated for reading tasks such as newspapers, nutrients on food can, and microwave timer (P < 0.05)., Conclusions: Longer time to perform TIADL is associated with decreased visual acuity, contrast sensitivity, and binocular visual field. TIADL and self-reported IADL are significantly correlated for reading tasks providing an accurate, complementary outcome measure in clinical practice and research., (© 2024. The Author(s).)

Purpose: This study aimed to assess grating visual acuity and functional vision in children with congenital Zika syndrome., Methods: Initial and final grating visual acuity was measured using Teller acuity cards. Cerebral vision impairment standardized tests were used to assess functional vision. Patients were referred to the early visual intervention program for visually disabled children. Neuroimaging was performed., Results: In this study, 10 children were included with an age range of 1-37 months. Eight patients presented with macular atrophic scars. Neuroimaging revealed microcephaly and cerebral abnormalities in all patients. Low vision and cerebral vision impairment characteristics were observed in all children. The final grating visual acuity in this group varied from 3.00 to 0.81 logMAR., Conclusions: The grating visual acuity test revealed low vision in all children with congenital Zika syndrome. Functional vision evaluation revealed cerebral vision impairment characteristics in all patients, who were referred to the early visual intervention program. Visual acuity improved in six children.

Lighting modification is commonly performed by optometrists and occupational therapists to enhance visibility and visual comfort among schoolchildren with low vision. The purpose of this study is to determine the optimal illumination level for visual function and visual comfort of schoolchildren with low vision and the relationship between them. A cross-sectional study was conducted to assess five levels of illumination ranging from 125 lux to 2000 lux to determine the optimal illumination for visual functions and visual comfort in schoolchildren with low vision from a special education school for blind in Malaysia. Purposive sampling was done to recruit forty-two schoolchildren with low vision for this study. Visual functions assessed were visual acuity, measured using the Early Treatment Diabetic Retinopathy Study LogMAR chart at distance and near, contrast sensitivity (CS) measured using the Pelli-Robson chart at distance and the Mars CS chart at near. Reading speed was determined using the Universiti Kebangsaan Malaysia Malay Language Related Word Reading Text test chart. Subjects were asked to rate their visual comfort using a validated questionnaire at the end of each measurement of visual functions and reading speed for the different illumination levels. Visual acuity and contrast sensitivity at distance and near, visual comfort and reading speed improved significantly with increase in illumination levels (p<0.05). However, the interaction between illumination level and level of low vision was not significant (p>0.05). Visual comfort was significantly associated with visual function (p<0.05), while direct association between visual comfort and illumination level was not significant (p>0.05). Optimal illumination for improvement of visual function, reading speed and visual comfort range from 276.67 lux to 701.59 lux. Majority of the schoolchildren with low vision had improved visual function, reading speed and visual comfort with increased illumination. Illumination of at least 600 lux is recommended for maximum visual functioning and visual comfort of schoolchildren with low vision., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Yong et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Central vision loss (CVL) is a major form of low vision that remains inadequately managed worldwide. This study evaluated the clinical efficacy of a novel head-mounted device (HMD), Onyx, designed to enhance visual function and vision-related quality of life for CVL patients. It employs a projection system that enables patients to leverage their residual peripheral vision for environmental awareness. It also integrates artificial intelligence to augment the automatic recognition of text, faces, and objects. In this single-center, prospective cohort study, 41 binocularly low vision patients with CVL were instructed to use Onyx for 4 to 6 h daily over a one-month period. Various metrics were assessed, including near and distance visual acuity (VA), recognition abilities for faces and objects, and the low vision quality-of-life (LVQOL) questionnaire scores, at the start and end of the study. The results showed significant improvements in near VA for 60.98% of the participants, distance VA for 80.49%, and recognition ability for 90.24%. 68.29% of the participants showed significant improvements in the LVQOL scores. Improvement in recognition ability was negatively correlated with baseline recognition ability. Additionally, improvement in the LVQOL scores was correlated with age and the baseline LVQOL score. Overall, the study found that the novel HMD significantly improved visual function and vision-related quality of life for low vision patients with CVL, highlighting the potential benefits and the need for further evaluation of such devices., (© 2024. The Author(s).)

Clinical Relevance: The support of students with a vision impairment throughout education could be enhanced by assessing the functional reading ability of the individual. This visual assessment could inform educators of individualised student needs and potentially improve the academic achievement for these students., Background: Support for children with a vision impairment within a classroom is typically based on clinical findings of distance visual acuity and visual fields. Therefore, determining optimal print size for reading is essential to ensure best academic outcomes. Secondary aims were to investigate the possible impact of underlying pathology on reading ability., Methods: Forty-seven participants were recruited from a state-wide support service for children with a vision impairment in South Australia. Three visual acuity groups were formed based on World Health Organisation definitions of mild, moderate, and severe vision impairment. Correlation between clinical measures of distance visual acuity using the Freiburg Visual Acuity Test, were compared with reading acuity and critical print size (smallest font before reading speed reduced) using Minnesota low vision reading chart (MNREAD)., Results: No significant correlations were found for mild (0.20-0.49 logMAR) and severe (1.00-1.52 logMAR) vision impairment groups between distance visual acuity and reading acuity read ( p  = .64, CI [-.585, .395]/ p  = .82, CI [-.48, .58]) or critical print size (p = .78 , CI [-.57, .45]/ p  = .43, CI [-.34, .68]. A significant correlation was found for the moderate vision impairment group: 0.50-0.99 logMAR for minimum reading acuity (p  < .001, CI [.44, .91]) and critical print size ( p  = .03, CI [.05, .80])., Conclusions: Standard clinical measures of distance visual acuity are an unpredictable estimate of reading ability in children with mild and severe vision impairment. Additional measures of functional near reading ability could provide a more meaningful indicator of reading ability and help provide optimum support to students through education.

Background: Severe fatigue is a common symptom for people with visual impairment, with a detrimental effect on emotional functioning, cognition, work capacity and activities of daily living. A previous study found that depression was one of the most important determinants of fatigue, but less is known about disease-specific factors in this patient population. This study aimed to explore the association between visual impairment severity and fatigue in adults with low vision, both directly and indirectly, with vision-specific factors and depression as potential mediators., Methods: Cross-sectional data were collected from 220 Dutch low vision service patients by telephone interviews. Fatigue was defined as a latent variable by severity and impact on daily life. Potential mediators included vision-related symptoms, adaptation to vision loss and depression. Hypothesized structural equation models were constructed in Mplus to test (in)direct effects of visual impairment severity (mild/moderate, severe, blindness) on fatigue through above mentioned variables., Results: The final model explained 60% of fatigue variance and revealed a significant total effect of visual impairment severity on fatigue. Patients with severe visual impairment (reference group) had significantly higher fatigue symptoms compared to those with mild/moderate visual impairment (β = -0.50, 95% bias-corrected confidence interval [BC CI] [-0.86, -0.16]) and those with blindness (β = -0.44, 95% BC CI [-0.80, -0.07]). Eye strain & light disturbance, depression and vision-related mobility mediated the fatigue difference between the severe and mild/moderate visual impairment categories. The fatigue difference between the severe visual impairment and blindness categories was solely explained by eye strain & light disturbance. Moreover, depressive symptoms (β = 0.65, p < 0.001) and eye strain & light disturbance (β = 0.19, p = 0.023) were directly associated with fatigue independent of visual impairment severity., Conclusions: Our findings indicate an inverted-U shaped relationship between visual impairment severity and fatigue in patients with low vision. The complexity of this relationship is likely explained by the consequences of visual impairment, in particular by strained eyes and depressive mood, rather than by severity of the disability itself., (© 2024. The Author(s).)

Background/objective: To determine the prevalence of visual impairment (VI), uncorrected refractive errors (URE), and effective refractive error coverage among individuals aged 15-50 years in Koshi Province, Nepal., Methods: A population-based cross-sectional study was conducted in Koshi Province in which 4800 participants were selected from 80 clusters. The study teams visited the selected households and conducted eye examinations. This included monocular unaided (and aided) visual acuity assessment using a Snellen chart with tumbling E optotypes at a distance of 6 meters. Near vision was assessed binocularly using the N notation chart at a fixed distance of 40 cm for each individual. Torchlight examination and distance direct ophthalmoscopy was done. VI was defined as presenting visual acuity worse than 6/12 in the better eye. URE was defined as presenting visual acuity worse than 6/12 and improving to 6/12 or better on using a pinhole. Near Vision Impairment was defined as binocular presenting near vision worse than N8 among those age 35 years and older., Results: In total, 4057 were examined (84.5% response rate). The prevalence of VI was 3.52% (95% CI:2.89-4.13; n = 143). The prevalence of URE in the better eye was 1.95% (95% CI:1.54-2.42; n = 79). The Refractive Error Coverage and Effective Refractive Error Coverage were 34.8% and 31.3% respectively. The prevalence of NVI was 34.24% (95% CI: 32.1-36.40; n = 666)., Conclusion: The prevalence of VI and  URE was low, attributed to the availability and uptake of services in Koshi province in Nepal., (© 2023. The Author(s), under exclusive licence to The Royal College of Ophthalmologists.)

In the context of blindness, studies on the recognition of facial expressions of emotions by touch are essential to define the compensatory touch abilities and to create adapted tools on emotions. This study is the first to examine the effect of visual experience in the recognition of tactile drawings of facial expressions of emotions by children with different visual experiences. To this end, we compared the recognition rates of tactile drawings of emotions between blind children, children with low vision and sighted children aged 6-12 years. Results revealed no effect of visual experience on recognition rates. However, an effect of emotions and an interaction effect between emotions and visual experience were found. Indeed, while all children had a low average recognition rate, the drawings of fear, anger and disgust were particularly poorly recognized. Moreover, sighted children were significantly better at recognizing the drawings of surprise and sadness than the blind children who only showed high recognition rates for joy. The results of this study support the importance of developing emotion tools that can be understood by children with different visual experiences., Competing Interests: Declaration of competing interest All authors disclose any financial and personal relationships with other people or organizations that could inappropriately influence their work., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

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., (© 2024 The Authors. Ophthalmic and Physiological Optics published by John Wiley & Sons Ltd on behalf of College of Optometrists.)

Significance: Future work should develop and evaluate interventional strategies to help overcome visual and health-related barriers to travel in visually impaired seniors and mitigate adverse impacts of loneliness for those who do not leave town., Purpose: Life space refers to the area in which a person travels within a given time period. We explored whether demographics, vision, and/or health characteristics were related to restrictions in self-reported life space for visually impaired seniors., Methods: Visually impaired (n = 114) clinical trial participants aged ≥55 years learned visual assistive iPhone apps and completed the following baseline questionnaires: Life Space, 36-Item Short-Form Health Survey, University of California, Los Angeles Loneliness Scale, and New-General Self-efficacy Scale. Multiple logistic regressions evaluated associations between life space and patient factors after accounting for their distance to the next county or state., Results: During 2021 to 2023, 17%, 43%, and 70% of participants had not left their town, county, or state, respectively, in the past 3 months, or planned to in the next 3 months. Those with reduced distance best-corrected visual acuity had greater odds of not leaving the county in these time frames (odds ratio [OR] = 3.5; p=0.04). Minority race was associated with greater odds of not leaving town or the county in the past 2 weeks or future 3 months (OR = 4.3 to 6.4; p=0.009 to 0.049). Increased self-efficacy was associated with reduced odds of not leaving the state in the past 3 months, next 3 months, or past and/or future 3 months (OR = 0.54 to 0.55; p=0.02 to 0.03). Better physical function was associated with reduced odds of not leaving the state in the past 2 weeks or 3 months (OR = 0.96 to 0.98; p=0.01 to 0.04). Increased loneliness was related to greater odds of not leaving town in the past and/or future 3 months (OR = 1.8 to 2.0; p=0.007 to 0.009)., Conclusions: Minority race, reduced vision, self-efficacy, and physical health were related to life space restrictions in this cohort of visually impaired seniors, whereas loneliness was greater among those who were not leaving town., Competing Interests: Conflict of Interest Disclosure: There are no relevant financial conflicts of interest for any author. The sponsor provided funding but was not involved in the study design, conduct, analysis, or manuscript preparation. The authors had access to and control of the data in this study. The authors were responsible for preparation of this manuscript and the decision to submit this article for publication. Each of the authors had full access to the study data and take full responsibility for their presentation in this article., (Copyright © 2024 American Academy of Optometry.)

Significance: This study has shown a vibrotactile sensory substitution device (SSD) prototype, VibroSight, has the potential to improve functional outcomes (i.e., obstacle avoidance, face detection) for people with profound vision loss, even with brief familiarization (<20 minutes)., Purpose: Mobility aids such as long canes are still the mainstay of support for most people with vision loss, but they do have limitations. Emerging technologies such as SSDs are gaining widespread interest in the low vision community. The aim of this project was to assess the efficacy of a prototype vibrotactile SSD for people with profound vision loss in the face detection and obstacle avoidance tasks., Methods: The VibroSight device was tested in a movement laboratory setting. The first task involved obstacle avoidance, in which participants were asked to walk through an obstacle course. The second was a face detection task, in which participants were asked to step toward the first face they detected. Exit interviews were also conducted to gather user experience data. Both people with low vision (n = 7) and orientation and mobility instructors (n = 4) completed the tasks., Results: In obstacle avoidance task, participants were able to use the device to detect (p<0.001) and avoid (p<0.001) the obstacles within a significantly larger range, but were slower (p<0.001), when compared with without the device. In face detection task, participants demonstrated a great level of accuracy, precision, and sensitivity when using the device. Interviews revealed a positive user experience, although participants identified that they would require a lighter and compact design for real-world use., Conclusions: Overall, the results verified the functionality of vibrotactile SSD prototype. Further research is warranted to evaluate the user performance after an extended training program and to add new features, such as object recognition software algorithms, into the device., Competing Interests: Conflict of Interest Disclosure: This study was supported in part by a research grant from Bionic Vision Technologies Inc. to LNA. In addition, XB and SS were employees of Bionic Vision Technologies during the study period, as software engineers. XB and SS oversaw the software logistics of the study (including participation during experimental sessions) but did not play a role in data analysis or interpretation. All authors have approved this manuscript., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American Academy of Optometry.)

Background: Visual perceptual learning (PL) shows promise for enhancing visual functions in individuals with visual impairment., Objective: This systematic review aimed to evaluate the effectiveness of PL in improving visual function., Study Eligibility: Eligible studies were those examining the efficacy of PL in individuals with low vision., Study Appraisal and Synthesis Methods: The review protocol was registered with the international Prospective Register of Systematic Reviews (ID CRD42022327545) and adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Screened studies were synthesized using random-effects meta-analysis and narrative synthesis following Synthesis Without Meta-analysis guidelines. The quality of the evidence was assessed using the Cochrane risk-of-bias tool and the JBI Critical Appraisal Tool for Quasi-Experimental studies., Results: Fifty studies were included, covering various visual impairments and employing different PL interventions. Most studies had low risk of bias. Meta-analysis showed significant improvement in visual search for individuals with cortical blindness (Hedges' g = 0.71; 95% confidence interval, 0.48 to 0.93; p=0.002); all other analyses did not show significant improvements-reading in central vision loss and cortical blindness, and visual field in peripheral vision loss and cortical blindness. However, the narrative synthesis provided evidence showing effectiveness, particularly in individuals with central vision loss and cortical blindness, demonstrating positive effects on reading, contrast sensitivity, visual field, and motion perception., Limitations: Variations in study design, PL protocols, outcome measures, and measurement methods introduced heterogeneity, limiting the analysis., Conclusions: The efficacy of PL in vision rehabilitation remains uncertain. Although meta-analysis results were mostly inconclusive, the narrative synthesis indicated improved visual functions following PL, consistent with individual study findings., Implications of Key Findings: Future research should optimize intervention parameters, explore long-term effects, and assess generalizability across diverse populations and visual impairment etiologies. Larger randomized controlled trials using standardized outcome measures are needed to advance the field., Competing Interests: Conflict of Interest Disclosure: None of the authors have reported a financial conflict of interest., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American Academy of Optometry.)

Significance: Individuals with reduced visual acuity (VA) may drive with bioptic telescopes in some jurisdictions. The effect of bioptic telescope use on on-road recognition distances is important for driving safety, as increased recognition distances increase the time available to react to road signs or driving events., Purpose: This study aimed to investigate the impact of bioptic telescope use on visual recognition of road signs, traffic lights, and hazards in an on-road driving environment in individuals with reduced VA., Methods: Ten individuals (mean ± standard deviation age, 39.1 ± 19.1 years) with reduced VA (trained to use bioptic telescopes) participated in a repeated-measures on-road experiment for two viewing conditions, with and without a bioptic telescope (randomized order). Participants underwent a clinical low vision assessment, including high-contrast VA with and without the bioptic telescope aligned, visual fields, and contrast sensitivity testing. For the driving component, participants seated in the front passenger seat of a moving car reported all road signs, traffic lights, and hazards (unpredictable road events that represent a risk to driving safety including other vehicles, cyclists, pedestrians) seen along a route that included suburban roads and highways. Video cameras captured participants' viewing behavior, verbal commentary, and the distance at which three pre-selected road signs were reported., Results: In the eye with the bioptic telescope, high-contrast VA improved from 0.75 ± 0.17 (without) to 0.25 ± 0.1 logMAR with the bioptic telescope. Bioptic telescope use did not affect the percentage of road signs, traffic lights, or hazards correctly recognized but did result in 2.6 times longer recognition distances (49 ± 23 vs. 19 ± 11 m, t9 = 5.02, p<0.001)., Conclusions: Road signs were recognized at significantly longer distances when using a bioptic telescope, confirming their positive impact on timely visual recognition of objects within the driving scene. Future work should explore whether this effect generalizes to individuals using bioptic telescopes when driving a vehicle., Competing Interests: Conflict of Interest Disclosure: None of the authors have reported a financial conflict of interest with this research work. Sharon L. Oberstein is codirector of a company that imports low vision aids and bioptic telescopes, but the company had no role in this research study., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American Academy of Optometry.)

Significance: Analyzing narratives in patients' medical records using a framework that combines natural language processing (NLP) and machine learning may help uncover the underlying patterns of patients' visual capabilities and challenges that they are facing and could be useful in analyzing big data in optometric research., Purpose: The primary goal of this study was to demonstrate the feasibility of applying a framework that combines NLP and machine learning to analyze narratives in patients' medical records. To test and validate our framework, we applied it to analyze records of low vision patients and to address two questions: Was there association between patients' narratives related to activities of daily living and the quality of their vision? Was there association between patients' narratives related to activities of daily living and their sentiments toward certain "assistive items"?, Methods: Our dataset consisted of 616 records of low vision patients. From patients' complaint history, we selected multiple keywords that were related to common activities of daily living. Sentences related to each keyword were converted to numerical data using NLP techniques. Machine learning was then applied to classify the narratives related to each keyword into two categories, labeled based on different "factors of interest" (acuity, contrast sensitivity, and sentiments of patients toward certain "assistive items")., Results: Using our proposed framework, when patients' narratives related to specific keywords were used as input, our model effectively predicted the categories of different factors of interest with promising performance. For example, we found strong associations between patients' narratives and their acuity or contrast sensitivity for certain activities of daily living (e.g., "drive" in association with acuity and contrast sensitivity)., Conclusions: Despite our limited dataset, our results show that the proposed framework was able to extract the semantic patterns stored in medical narratives and to predict patients' sentiments and quality of vision., Competing Interests: Conflict of Interest Disclosure: None of the authors have reported a financial conflict of interest., (Copyright © 2024 American Academy of Optometry.)

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., Competing Interests: Conflict of Interest Disclosure: None of the authors have reported a financial conflict of interest., (Copyright © 2024 American Academy of Optometry.)

Significance: Poor visibility of indoor features such as steps and ramps can pose mobility hazards for people with low vision. For purposes of architectural design, it is important to understand how design parameters such as the illumination level of an indoor space affect the visibility of steps and ramps., Purpose: This study was aimed to examine the effect of typical variation in photopic illumination level in an indoor space on the visibility of steps and ramps for individuals with low vision., Methods: Steps and ramps were constructed in a large windowless room illuminated by overhead lights. Subjects with low vision completed a 5-alternative forced choice task to recognize the targets at three levels of photopic illumination, i.e., 800, 80, and 8 lux, and gave confidence ratings about their judgments on a 5-point scale. Acuities and contrast sensitivities of the subjects were also measured at each illumination level. For comparison, a group of normally sighted subjects with simulated acuity reduction also completed the step-and-ramp recognition task., Results: For both groups of subjects, recognition accuracy was not affected by illumination level. For subjects with low vision, however, there was a significant effect of illumination level on confidence rating: subjects became more confident about their judgments with increasing illumination. There was also a weak effect of illumination level on acuity and contrast sensitivity, both worsening with decreasing illumination. Recognition performance was best predicted by contrast sensitivity, whereas confidence was best predicted by visual acuity., Conclusions: Illumination variation over a typical photopic range in an indoor space had minimal effect on the objective visibility of steps and ramps for people with low vision. However, illumination level affected subjects' confidence in hazard recognition. Design decisions on parameters such as illumination should consider the consequences on both the objective and the subjective accessibility of a space., Competing Interests: Conflict of Interest Disclosure: None of the authors have reported a financial conflict of interest., (Copyright © 2024 American Academy of Optometry.)

Significance: Autonomous vehicles (AVs) have the promise to be an alternative transportation solution for those with vision loss. However, the impact of vision loss on the perceptions and concerns of AVs is unknown. This study therefore examined whether AVs are perceived differently by blind, visually impaired (VI), and normally sighted people., Purpose: This study compared the perceptions of AVs among the blind, VI, and normally sighted., Methods: Participants' opinions on four perception measures (general opinion, trust, impact on quality of life, and intention to use AVs) and nine concerns regarding AVs were measured. The survey was administered to 51 normally sighted, 68 VI, and 65 blind participants. Analyses of covariance assessed whether the four perception measures and nine concerns varied by vision status (normal vision, VI, blind) and driving status (driver, nondriver). Univariate correlations and multiple regression analyses identified associations and predictors of AV perceptions and concerns from demographic, mood, cognition, travel behavior, and vision measures, which included visual acuity, contrast sensitivity, and visual field., Results: The blind (p<0.001), VI (p<0.001), and nondrivers (p<0.001) showed a greater intention to use AVs compared with those with normal vision and drivers. Similar findings were found for the other perception measures. As visual acuity, contrast sensitivity, and visual field extent declined, positivity toward AVs increased (p<0.001). Visual field extent best predicted general opinion and trust in AVs, whereas driving measures were the best predictors of impact on quality of life and intention to use AVs. Concerns about AVs showed no differences based on vision (p=0.94) or driving (p=0.63) status., Conclusions: Individuals with vision loss expressed more acceptance of AVs despite their concerns. How positive someone is toward AVs appears to be dependent on their visual field extent and driving status., Competing Interests: Conflict of Interest Disclosure: None of the authors have reported a financial conflict of interest., (Copyright © 2024 American Academy of Optometry.)

Purpose: We aimed to develop a paradigm that can efficiently characterize motion percepts in people with low vision and compare their responses with well-known misperceptions made by people with typical vision when targets are hard to see., Methods: We recruited a small cohort of individuals with reduced acuity and contrast sensitivity (n = 5) as well as a comparison cohort with typical vision (n = 5) to complete a psychophysical study. Study participants were asked to judge the motion direction of a tilted rhombus that was either high or low contrast. In a series of trials, the rhombus oscillated vertically, horizontally, or diagonally. Participants indicated the perceived motion direction using a number wheel with 12 possible directions, and statistical tests were used to examine response biases., Results: All participants with typical vision showed systematic misperceptions well predicted by a Bayesian inference model. Specifically, their perception of vertical or horizontal motion was biased toward directions orthogonal to the long axis of the rhombus. They had larger biases for hard-to-see (low contrast) stimuli. Two participants with low vision had a similar bias, but with no difference between high- and low-contrast stimuli. The other participants with low vision were unbiased in their percepts or biased in the opposite direction., Conclusions: Our results suggest that some people with low vision may misperceive motion in a systematic way similar to people with typical vision. However, we observed large individual differences. Future work will aim to uncover reasons for such differences and identify aspects of vision that predict susceptibility., Competing Interests: Conflict of Interest Disclosure: None of the authors have reported a financial conflict of interest. The sponsor provided financial support, but had no role in the study design, conduct, analysis and interpretation, or writing of the report., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American Academy of Optometry.)

Purpose : To assess the prevalence of alternate etiology/co-existing pathology among patients with amblyopia, and to characterize factors contributing to over-diagnosis of amblyopia. Methods : We retrospectively reviewed records of children (from 1 January 2016 to 31 December 2019) who were initially diagnosed as "amblyopia" but later an alternate diagnosis for subnormal vision was established. Patients who had a best corrected visual acuity (BCVA) of ≤20/32 (0.2 logMAR) after compliant amblyopia therapy were divided into 2 groups: those with refractory amblyopia (BCVA improvement from baseline <1 logMAR line) and residual amblyopia (BCVA improvement from baseline >1 logMAR line). Data was collected for presence/absence of amblyogenic risk factors, history, ocular examination, and investigations leading to the final alternate diagnosis. We analyzed the factors that contributed to the initial over-diagnosis of amblyopia using the diagnostic error evaluation and research (DEER) taxonomy tool. Results : During the study period, 508 children with an initial diagnosis of amblyopia met the study criteria. Among these 508 children, 466 were diagnosed to have amblyopia alone, while 26 children (5.1%, median age: 7 years, 17 boys: 9 girls) were revised to have an alternate diagnosis/co-existing pathology. These 26 patients comprised of 2 groups: children referred to us as amblyopia but rediagnosed to have an alternate diagnosis; and a second subset, initially diagnosed by us to have amblyopia, but later found to have alternate diagnosis/co-existing pathology. Subclinical optic neuritis (50%, 13 children), and occult macular dystrophy (OMD) (38.4%, 10 children) were the most frequent alternative diagnoses. Children with ametropic amblyopia (8/26, 30.7%) were most frequently misdiagnosed. Risk factors that led to an initial diagnosis of amblyopia were: high refractive error and heterotropia in 7 patients each (26.9%), anisometropia in 12 (46.1%), and prior pediatric cataract surgery in 4(15.3%). No improvement in BCVA in 21/26 (80.7%) children led to suspicion of co-existing etiology. Other clues were optic disc pallor (11), subnormal color vision (7), history of parental consanguinity in 7, and preceding febrile illness/rhinitis in 1 child. The DEER taxonomy tool suggested that the most common reasons for diagnostic errors were over-emphasis on amblyopia. Conclusion : Our study suggests that 5% of children diagnosed with amblyopia might have co-existing/alternate etiology. Most common co-existing etiologies were subclinical optic neuropathy, and OMD. No improvement in BCVA, subtle history and examination findings prompted further workup. Not considering co-existing etiologies was the most common reason for an initial overdiagnosis of amblyopia.

There is limited information on functional low vision (FLV) in Latin America, especially in individuals under 50 years of age. In the present study, we retrospectively evaluated the medical records of 1393 consecutive subjects seen at a Brazilian tertiary rehabilitation service, from February 2009 to June 2016. We collected sociodemographic, clinical data, and information on optical aids and spectacle prescription. Subjects were divided into three age groups: 0 to 14 years old (children), 15 to 49 years old (young adults), and 50 years or older (older adults). The main etiologies leading to FLV in children were cerebral visual impairment (27.9%), ocular toxoplasmosis (8.2%), and retinopathy of prematurity (7.8%). In young adults, retinitis pigmentosa (7.4%) and cone/rod dystrophy (6.5%) were the most frequent, while in older adults, age-related macular degeneration (25.3%) and diabetic retinopathy (18.0%) were the leading causes. Our results indicate that preventable diseases are important causes of FLV in children in the area, and proper prenatal care could reduce their burden. The increasing life expectancy in Latin America and the diabetes epidemic are likely to increase the demand for affordable, people-centered rehabilitation centers, and their integration into health services should be planned accordingly., (© 2022. The Author(s).)

Purpose: To evaluate the impact of glaucoma on health-related quality of life (HRQoL) and mental health in the ageing population of Finland., Methods: Altogether 7380 and 5774 Finnish individuals aged 30 years and older with known eye disease status were studied in 2000 and 2011, respectively, in two population-based surveys, including an 11-year follow-up of 4683 participants. Data on HRQoL (EQ-5D-3L, 15D), depression (BDI), psychological distress (GHQ-12) and eye disease diagnoses were obtained from self-reported assessments. Information on glaucoma was complemented with the medication, diagnosis and eye surgery data obtained from the Finnish Health Registries. Distance visual acuity was assessed using the Snellen eye chart test. In logistic regression analyses, data were corrected for age, gender and the most common comorbidities., Results: Glaucoma patients with verified diagnosis (n = 192 in 2000, n = 202 in 2011) and individuals with self-suspected glaucoma (n = 100 in 2000, n = 41 in 2011) showed a significant decrease in their HRQoL. Glaucoma was also associated with worsened overall mental health based on BDI and GHQ-12 results. Visual impairment associated with glaucoma is the major determinant of the reduced HRQoL and mental health. Neither glaucoma medication nor glaucoma surgery affected these parameters. The impact of glaucoma on HRQoL and mental health diminished between 2000 and 2011 in a cross-sectional setting. The newly diagnosed glaucoma during the 11-year follow-up had a minimal effect on them., Conclusion: Glaucoma patients show reduced HRQoL and mental health, which is associated with vision loss regardless of the awareness or treatment of the disease. However, this effect seems to be diminishing over time, and the newly diagnosed glaucoma did not show a significant effect on either HRQoL or mental health., (© 2021 The Authors. Acta Ophthalmologica published by John Wiley & Sons Ltd on behalf of Acta Ophthalmologica Scandinavica Foundation.)

Purpose: To describe the natural course, phenotype, and genotype of patients with X-linked retinoschisis (XLRS)., Design: Retrospective cohort study., Participants: Three hundred forty patients with XLRS from 178 presumably unrelated families., Methods: This multicenter, retrospective cohort study reviewed medical records of patients with XLRS for medical history, symptoms, visual acuity (VA), ophthalmoscopy, full-field electroretinography, and retinal imaging (fundus photography, spectral-domain [SD] OCT, fundus autofluorescence)., Main Outcome Measures: Age at onset, age at diagnosis, severity of visual impairment, annual visual decline, and electroretinography and imaging findings., Results: Three hundred forty patients were included with a mean follow-up time of 13.2 years (range, 0.1-50.1 years). The median ages to reach mild visual impairment and low vision were 12 and 25 years, respectively. Severe visual impairment and blindness were observed predominantly in patients older than 40 years, with a predicted prevalence of 35% and 25%, respectively, at 60 years of age. The VA increased slightly during the first 2 decades of life and subsequently transitioned into an average annual decline of 0.44% (P < 0.001). No significant difference was found in decline of VA between variants that were predicted to be severe and mild (P = 0.239). The integrity of the ellipsoid zone (EZ) as well as the photoreceptor outer segment (PROS) length in the fovea on SD OCT correlated significantly with VA (Spearman's ρ = -0.759 [P < 0.001] and -0.592 [P = 0.012], respectively). Fifty-three different RS1 variants were found. The most common variants were the founder variant c.214G→A (p.(Glu72Lys)) (101 patients [38.7%]) and a deletion of exon 3 (38 patients [14.6%])., Conclusions: Large variabilities in phenotype and natural course of XLRS were seen in this study. In most patients, XLRS showed a slow deterioration starting in the second decade of life, suggesting an optimal window of opportunity for treatment within the first 3 decades of life. The integrity of EZ as well as the PROS length on SD OCT may be important in choosing optimal candidates for treatment and as potential structural end points in future therapeutic studies. No clear genotype-phenotype correlation was found., (Copyright © 2021 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Purpose : To investigate the factors affecting the reading speed of patients with central scotoma due to age-related macular degeneration (AMD). Materials and Methods: We included 63 eyes of 63 patients with AMD who applied to our low vision clinic between August 2018 and September 2019 in this prospective study. We evaluated socio-demographic characteristics, eye examination findings and Minnesota Low Vision Reading Test (MNREAD) results. We used the MAIA microperimeter device to evaluate the properties of the preferred retinal locus for fixation (PRL) of the patients. Evaluations included the assessment of the effects of all parameters on reading speed. Results: The PRL was most commonly in the nasal (31%) and superior (26%) quadrants. Twenty-nine percent of the cases preferred the left visual field. PRL localization had no effect on reading speed, whereas, fixation stability, educational status, presence of foveal absolute scotoma, reading acuity and duration of reading interruption were found to have the most significant effects. Multiple regression analysis showed that reading speed decreased by 67 units in the presence of unstable fixation, by 17 units in the presence of foveal absolute scotoma, by 3 units with every 0.1 increase in logMAR value, and by 1.7 units with every 1-year increase in reading interruption. Additionally, being a university graduate was associated with an increased reading speed (by 18 units) Conclusion: Increased reading performance is one of the factors that can improve quality of life. The factors found to affect the reading speed in the current study may guide the rehabilitation process in low vision patients.

Background : To describe genetic molecular findings in individuals with congenital nystagmus, foveal hypoplasia, and subnormal vision, with normal ocular pigmentation (absence of diffuse transillumination or transparent retinal pigment typical for albinism). Methods : This is a retrospective, multicenter study of ophthalmic, systemic, and genetic features, as collected from medical records of patients diagnosed with infantile nystagmus and foveal hypoplasia. Ophthalmic findings include best-corrected visual acuity (BCVA), biomicroscopic examination, cycloplegic refraction, retinal examination, macular optical coherence tomography, and electroretinography. Genetic information was retrieved from the participating genetic clinics and included ethnicity and molecular diagnosis. Results : Thirty-one individuals met the inclusion criteria and had a secure molecular diagnosis. Mutations in two genes predominated, constituting 77.4% of all the represented genes: SLC38A8 (45.1%) and PAX6 (32.3%). Seventy-eight percent of the subjects who had a measurable BCVA had moderate and severe visual impairment (range 20/80 to 20/270). Most patients with a mutation in SLC38A8 had mild to moderate astigmatism, while most patients with PAX6 mutation had moderate and severe myopia. Patients in the PAX6 group had variable degrees of anterior segment manifestations. Conclusion : In our cohort, the main causative genes for congenital nystagmus and foveal hypoplasia in normally pigmented eyes were SLC38A8 and PAX6 . A mild phenotype in PAX6 mutations may be an under-diagnosed cause of nystagmus and foveal hypoplasia. Reaching an accurate genetic diagnosis is essential for both the patients and their family members. This enables predicting disease prognosis, tailoring correct follow-up, and providing genetic counseling and family planning to affected families.

Objectives: To compare the quality of life assessed by the Low Vision Quality of Life Questionnaire (LVQOL) and National Eye Institute Visual Function Questionnaire (NEI VFQ-25) in patients with low vision., Materials and Methods: A total of 64 consecutive patients who presented to the Ankara University Low Vision Rehabilitation Department for the first time were included in the study. Patients aged 18 or older who had a best-corrected visual acuity of less than 20/60 or a visual field of equal to or less than 20° from the fixation point in the better eye were included. After examination, the patients were asked to complete the LVQOL and NEI VFQ-25 questionnaires., Results: A very strong correlation was found between the total scores of the two questionnaires. A strong correlation was found between the "distance vision" subscale score of LVQOL and "distance activities" subscale score of NEI VFQ-25. There was also a strong correlation between the "reading and fine work" subscale score of LVQOL and "near activities" subscale score of NEI VFQ-25. There was a weak correlation between the LVQOL total score and visual acuity. There were moderate negative correlations between age at disease onset and the total scores of the two questionnaires., Conclusion: Both the LVQOL and NEI VFQ-25 are able to quantify the quality of life of individuals with low vision and it is possible to compare the studies carried out with these two questionnaires which are validated in Turkish.

In children with Down syndrome (DS) development of visual, motor and cognitive functions is atypical. It is unknown whether the visual impairments in children with DS aggravate their lag in cognitive development. Visual impairment and developmental lags in adaptive behaviour and executive functions were assessed in 104 children with DS, 2-16 years, by comparing their adaptive behaviour, executive functions and visual acuity (distant and near) scores against published age-matched norm scores of typically developing children. Associations between these lags were explored. Mean (± SEM) differences to age-matched norms indicated reduced performance in DS: Vineland Screener questionnaire, - 63 ± 3.8 months; task-based Minnesota Executive Function Scale (MEFS), - 46.09 ± 2.07 points; BRIEF-P questionnaire, 25.29 ± 4.66 points; BRIEF parents' and teachers' questionnaire, 17.89 ± 3.92 points and 40.10 ± 3.81 points; distant and near visual acuity, 0.51 ± 0.03 LogMAR and 0.63 ± 0.03 LogMAR (near - 0.11 ± 0.04 LogMAR poorer than distant). Adaptive behaviour (Vineland-S) correlated with the severity of visual impairment (r = - 0.396). Children with DS are severely impaired in adaptive behaviour, executive functions and visual acuities (near visual acuity more severely impaired than distant visual acuity). Larger impairment in adaptive behaviour is found in children with larger visual impairment. This supports the idea that visual acuity plays a role in adaptive development.

Significance: The prevalence of dry eye disease and low vision increases with age; they share risk factors and can be the result of underlying common causes. They are generally studied separately; however, combining these perspectives is relevant for research on assistive technology given that sustained focus affects the tear film because of decreased blinking rates., Purpose: The objective of this study was to elucidate to which extent dry eye disease risk factors, signs, and symptoms are assessed in low vision patients who receive an eye examination as part of their vision rehabilitation services., Methods: Using a retrospective chart review, dry eye disease risk factors, signs, or symptoms were extracted from 201 randomly selected files that contained an eye examination in the past 5 years from two vision rehabilitation centers., Results: Demographic variables of charts from the two sites did not differ (mean visual acuity, 0.85 logMAR [standard deviation, 0.53; range, 0 to 2.3]; mean age, 71.2 years [standard deviation, 19 years; range, 24 to 101 years]). Fifty charts (25%) mentioned at least one dry eye disease symptom. Sixty-one charts (30.3%) reported systemic medications that can exacerbate dry eye disease, whereas 99 (49.2%) contained at least one systemic disease thought to contribute to dry eye disease symptoms; 145 (72.1%) mentioned at least one type of ocular surgery. Artificial tears were documented in 74 charts (36.8%). Few specific dry eye tests were performed, with the exception of corneal integrity assessment reported in 18 charts (8.95%)., Conclusions: Low vision patients have multiple risk factors for dry eye disease; however, dry eye disease tests were not frequently performed in comprehensive low vision eye examinations in this sample. More efforts should be made to assess dry eye disease to enhance comfort and functional vision, especially with the increasing demands of digital devices as visual aids., Competing Interests: Conflict of Interest Disclosure: Both EB and WW are professors at the University of Montreal. Authors RA and GB-S were students (now graduated) at the time of the study. None of the authors have any direct conflict of interest with this article., (Copyright © 2021 American Academy of Optometry.)

Significance: This article summarizes the evidence for a higher prevalence of binocular vision dysfunctions in individuals with vision impairment. Assessment for and identification of binocular vision dysfunctions can detect individuals experiencing difficulties in activities including reading, object placement tasks, and mobility.Comprehensive vision assessment in low vision populations is necessary to identify the extent of remaining vision and to enable directed rehabilitation efforts. In patients with vision impairment, little attention is typically paid to assessments of binocular vision, including ocular vergence, stereopsis, and binocular summation characteristics. In addition, binocular measurements of threshold automated visual fields are not routinely performed in clinical practice, leading to an incomplete understanding of individuals' binocular visual field and may affect rehabilitation outcomes.First, this review summarizes the prevalence of dysfunctions in ocular vergence, stereopsis, and binocular summation characteristics across a variety of ocular pathologies causing vision impairment. Second, this review examines the links between clinical measurements of binocular visual functions and outcome measures including quality of life and performance in functional tasks. There is an increased prevalence of dysfunctions in ocular alignment, stereopsis, and binocular summation across low vision cohorts compared with those with normal vision. The identification of binocular vision dysfunctions during routine low vision assessments is especially important in patients experiencing difficulties in activities of daily living, including but not limited to reading, object placement tasks, and mobility. However, further research is required to determine whether addressing the identified deficits in binocular vision in low vision rehabilitative efforts directly impacts patient outcomes., Competing Interests: Conflict of Interest Disclosure: JT, MK, and AL receive salary support from Guide Dogs New South Wales/Australian Capital Territory, and JM is an employee of Guide Dogs New South Wales/Australian Capital Territory. JH and VK are recipients of Australian Government Research Training Program scholarships and PhD scholarships provided by Guide Dogs New South Wales/Australian Capital Territory. Guide Dogs New South Wales/Australian Capital Territory played no role in the conceptualization of this article, and the authors have no proprietary interest in any of the materials mentioned in this article., (Copyright © 2021 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American Academy of Optometry.)

Purpose: Low Vision Aids (LVAs) can have a transformative impact on people living with sight loss, yet the everyday requirements for developing such devices remain poorly understood and defined. This study systematically explored LVA requirements through a structured de-brief interview following a real-world self-recording study. The purpose of this work was to define the actual needs of those living with sight loss so that low vision services can better address them in future., Methods: Thirty-two visually impaired volunteers with varying levels of previous LVA experience participated in a de-brief interview centred around a structured questionnaire. The de-brief followed a one-week real-world study during which participants used recoding spectacles to capture and narrate all situations in which they would use a 'perfect sight aid'. Content and thematic analyses were used to analyse interviews which had the purpose of contextualising these recordings and exploring requirements around psychological, functional and design factors., Results: Participants reported that 46% of tasks which they had recorded were most important to them. Of these tasks, 82% were encountered frequently. Few tasks emerged as very important across many participants, the remaining tasks reflecting individual lifestyles or circumstances. Every participant used at least one LVA in their everyday life and 72% identified further coping strategies. Current LVAs identified as consistently poor were distance LVAs, with all other devices receiving mixed or only positive feedback. Around two-thirds of participants would prefer LVA use on an ad-hoc / quick access basis rather than over long periods of time, and just over half would prefer to carry it rather than wearing it all day. Lack of consistency in these responses illustrated potentially different user clusters with divergent design needs. Two-thirds of participants emphasised the desire for a discreet LVA that does not attract attention. However, since half of all participants felt self-conscious in public or in front of other people when wearing the small recording spectacles, this may not be technically achievable., Conclusions: There is a substantial opportunity for new LVAs to address visual needs that traditional devices and coping strategies cannot support. Functional, psychological and design factors require careful consideration for future LVAs to be relevant and widely adopted., (© 2021 The Authors. Ophthalmic and Physiological Optics published by John Wiley & Sons Ltd on behalf of College of Optometrists.)

Purpose: Posttraumatic stress disorder (PTSD) is a mental health problem with a negative impact on quality of life. Little is known about the relationship between PTSD and visual impairment. According to diagnostic criteria for PTSD, vision loss in itself is generally not considered as a traumatic event. PTSD in people with visual impairment is more likely to be the result of traumatic events, which are not directly related, or are only indirectly related to, visual impairment. The purpose of this systematic review was to describe and discuss the literature on the development of PTSD in people with visual impairment., Methods: A literature search in PubMed, Embase, PsycINFO and Web of Science was performed up to 15 November 2019 in collaboration with a medical information specialist. Additional search strategies included hand searches of references of retrieved papers and free-text hand searches in Google Scholar. Thematic content analysis of the extracted data was carried out in order to identify main themes and subthemes., Results: Findings from 13 articles are presented in a narrative manner along three main themes: (1) posttraumatic stress disorder; (2) traumatic events and (3) impact of traumatic events. People with visual impairments may be at higher risk of being exposed to certain potentially traumatic events. Limited/restricted access to situational information during events may contribute to the stressfulness of the experience. Furthermore, visual impairment may shape the impact of traumatic events., Conclusions: The current evidence suggests some unique experiences and challenges for people who are visually impaired. PTSD was prevalent in this population, and prevalence rates ranged from 4% to 50%. Future research may focus on gaining insight into the extent and burden of PTSD, and exploring help-seeking behaviour and treatment needs among those with visual impairment and PTSD., (© 2021 The Authors. Ophthalmic and Physiological Optics published by John Wiley & Sons Ltd on behalf of College of Optometrists.)

Purpose: This study examined the effectiveness of the LuxIQ, the Apple iPad and a smart bulb in assessing optimal colour and illumination to facilitate reading in younger, older and visually impaired adults., Methods: Participants read standardised texts at baseline (normal lighting/no device), then using the Apple iPad, LuxIQ and smart bulb, with their normal vision (20/20 condition) and using a simulated reduction in visual acuity/contrast sensitivity (20/80 condition). Visually impaired participants followed the same procedure used in the 20/80 condition., Results: There was a significant interaction between condition and device in younger, F(1.5, 43.51) = 30.41, p < 0.001, ω 2  = 0.34 and older, F(1.5, 4.51) = 4.51, p = 0.03, ω 2  = 0.05 adults with normal vision, and there was a significant effect of device, F(2, 58) = 5.95, p = 0.004, ω 2  = 0.12 in visually impaired adults. In the 20/20 condition, age and colour predicted reading speed, F(3, 176) = 36.25, p < 0.001, Adj. R 2  = 0.37, whereas age, lighting and colour predicted reading speed, F(3, 176) = 36.25, p < 0.001, Adj. R 2  = 0.37 in the 20/80 condition. In the visual impairment condition, lighting, colour and impairment severity predicted reading speed, F(3, 85) = 10.10, p < 0.001, Adj. R 2  = 0.24., Conclusions: The clinical implications of this study are that reading speeds improve in individuals with low vision under improved lighting conditions, specifically, with higher levels of luminance and colour temperature. The effectiveness of the devices varied across groups; however, the LuxIQ was the only device to improve reading speeds from baseline in older adults with visual impairments., (© 2021 The Authors Ophthalmic and Physiological Optics © 2021 The College of Optometrists.)

Background: It is estimated that approximately 1.3 billion people live with some form of distance or near visual impairment. Numerous studies have been carried out to evaluate the effects of biofeedback (BF) and establish if it could be a useful tool in vision rehabilitation for various eye diseases., Objective: This systematic review aimed: 1) to examine the current evidence of BF efficacy for the rehabilitation of the visually impaired and 2) to describe methodological variations used in previous BF studies to provide recommendations for vision rehabilitation interventions., Methods: A systematic review was conducted in the Medline, PubMed, Cochrane Library and Web of Science databases to collect documents published between January 2000 and May 2020. Of the 1,960 studies identified, 43 met the criteria for inclusion. The following information was collected from each study: sample size, control group, any eye disease, apparatus used, frequency and number of sessions of BF, main outcomes of training and whether a follow-up was conducted. The first group included studies published as scientific articles in peer-reviewed journals. The second group included abstracts of studies presented at peer-reviewed conferences. Publications were also grouped according to the eye disease treated., Results: 25 articles and 18 peer-reviewed conference abstracts (PRCAs) were included in this review. BF stimulation is a commonly used technique for the treatment of visual impairment caused by macular disease. Most BF studies evaluate the effect of training on the preferred retinal locus (PRL), particularly with regard to fixation location and stability. Across these studies, participants who received BF intervention improved fixation stability and reading speed. High variability in the number of sessions and the duration of BF training was found. Most studies did not use a control group., Conclusions: The findings of this review present evidence for biofeedback treatment in vision rehabilitation, with improved oculomotor abilities. Currently, it is not possible to formulate evidence-based recommendations for a standard training procedure due to the poor quality of existing randomised controlled trials. High-quality studies are needed to develop standard protocols for a range of eye diseases., (© 2021 The Authors Ophthalmic and Physiological Optics © 2021 The College of Optometrists.)

Purpose: The prevalence of depression in people with low vision is high and often goes undiagnosed. There is the potential for those who provide low vision services to perform concurrent depression screening. However, prior training in depression identification and suitable referral pathways is required. The aims of this study were: (1) to assess the impact of a training programme on practitioners' confidence and behaviour in addressing depression in patients with low vision, and (2) to review the training programme and identify areas for further development., Methods: A convergent mixed methods approach was used. Questionnaires were completed by practitioners pre-, immediately post- and 6 months post- training (n = 40) to assess practitioner confidence in approaching depression in patients with low vision. Qualitative interviews were performed with a subset of practitioners 6 months post-training (n = 9). Additionally, routine data from the Low Vision Service Wales (LVSW) database was used to determine the change in the number of practitioners identifying depression in patients, and the change in the number of patients identified at risk of depression 6 months post-training., Results: Of the 148 practitioners who completed low vision assessments pre- and post-training, 28 (18.9%) documented risk of depression in their patients pre-training, which increased substantially to 65 (43.9%) post-training (p < 0.0001). Mixed methods analysis confirmed increased documentation of depressive symptoms by practitioners. Practitioner confidence increased following training, with 92.3% feeling more confident to approach emotional issues with patients and 92.2% intending to use the recommended screening tool to identify depression. Interviews provided insight into areas where confidence was still lacking. Quantitative questionnaires revealed that training content was considered appropriate by 91% of participants. Interviews confirmed these findings while expanding upon possibilities for programme improvement., Conclusions: Training for depression screening was found to be time-efficient and acceptable for LVSW practitioners and shown to increase practitioner confidence in the identification of depression. Additionally, the programme changed behaviour, resulting in an increase in the identification of depression in patients with low vision. However, this is a complex topic and ongoing development is required to embed depression screening as an integral part of low vision services., (© 2021 The Authors. Ophthalmic and Physiological Optics published by John Wiley & Sons Ltd on behalf of College of Optometrists.)

Purpose: To assess the frequency of macular cysts (MCs) in retinal detachment treated with silicone oil and evaluate their impact on visual acuity and macular vascularization using optical coherence tomography-angiography., Methods: Forty-three eyes of 41 patients treated with silicone oil for retinal detachment were retrospectively studied. Best-corrected visual acuity and 6- × 6-mm optical coherence tomography-angiography examination at least 3 months after silicone oil removal were reviewed. In eyes with MCs, cyst area was measured on the en face optical coherence tomography-angiography image using ImageJ. Density of superficial capillary plexus and area of superficial foveal avascular zone were generated by the optical coherence tomography-angiography. Density of deep capillary plexus and deep foveal avascular zone area were measured using ImageJ., Results: Twenty-five eyes (58%) presented with MCs. Cysts were exclusively located in the inner nuclear layer in 60% of cases. Mean best-corrected visual acuity in the MC group was lower than that of the non-MC group (P = 0.012). Macular cyst area negatively correlated with best-corrected visual acuity (P = 0.0201). Density of superficial capillary plexus was higher in the MC group (P < 0.0001), whereas area of superficial foveal avascular zone was lower (P < 0.0001). Macular cyst area negatively correlated with density of deep capillary plexus (P < 0.001)., Conclusion: The incidence of INL-MCs after silicone oil removal is high. These are associated with impaired vision and macular vascular remodeling. We highlight their similarity with the "retrograde maculopathy" phenomenon.

Purpose: To evaluate the efficacy of a new laser imaging device that projects images onto functioning macular areas, to improve visual acuity (VA) in low-vision patients with macular diseases., Methods: An interventional case series of consecutive patients with low vision in their right eyes (RE). RE VA was measured by showing the patients digits of various standard sizes and measuring their best-corrected VA (BCVA). Then, using the I.C.INSIDE device to project the same standard digits onto functioning macular areas. Patient's ability to recognize the digits with the I.C.INSIDE device was correlated with patient's performance using telescopic low-vision aids. The main outcome measure was change in VA with the different visual aids., Results: Eleven patients (6 males and 5 females) with an average age of 75 ± 6.7 years and low vision in their RE due to macular diseases were included in the study. Baseline BCVA was 1.554 ± 0.50 logMAR. Low-vision aids improved mean VA in 10 patients to 0.64 ± 0.40 logMAR ( p < .0001), further improvement was noticed in 8 patients to 0.35 ± 0.16 logMAR ( p < .0001) using the laser device, but, three patients did not recognize any digit using the laser device., Conclusions: The I.C.INSIDE device significantly improved baseline VA in low-vision patients with macular diseases, using extra-foveal fixation.

Purpose: To describe the indications and prognosis for keratoplasty in eyes with severe visual impairment and blindness due to corneal diseases in India., Methods: This hospital-based cross-sectional study included 1 057 215 new patients presenting to a multitier ophthalmology network from 2016 to 2018. All patients with a central corneal pathology and best corrected visual acuity of less than 20/200 in the affected eye(s) were identified as cases and grouped according to laterality. The main outcome measure was the prognosis for keratoplasty, based on the surgical indication., Results: A total of 28 824 (2.73%) patients were identified with severe visual impairment or blindness due to corneal diseases; of which, 22 582 (78.3%) had unilateral and 6242 (21.7%) had bilateral affliction. Overall, 85% of the corneal pathologies were due to avoidable causes, which accounted for 97% and 63% of the unilateral and bilateral cases, respectively (p<0.0001). The most common aetiologies were microbial keratitis (27.2%) and corneal opacification (25.5%) in unilateral cases; and corneal opacification (38.2%) and ectasias (14.5%) in bilateral cases. Overall, 60.1% of affected eyes carried a fair to poor prognosis for keratoplasty. However, while in unilateral cases only 29.9% of eyes carried good to excellent prognosis for keratoplasty, in bilateral cases, 58% of eyes carried good to excellent prognosis for keratoplasty (p<0.0001)., Conclusions: The indications and prognosis for keratoplasty varied greatly based on whether the affliction was unilateral or bilateral. Most of the eyes affected by corneal visual impairment or blindness, however, carried an unfavourable prognosis for keratoplasty., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

Purpose: To analyze the principal cause for poor vision in eyes with best-corrected visual acuity (BCVA) of 20/200 or worse 2 years after neovascular age-related macular degeneration (nAMD)., Design: Prospective cohort study of participants enrolled in a clinical trial of oral supplements., Participants: Age-Related Eye Disease Study 2 (AREDS2) participants whose eyes began anti-vascular endothelial growth factor (VEGF) therapy for incident nAMD and had data available at 2 years., Methods: Participants underwent refracted BCVA testing, ophthalmoscopic examination, and fundus photography at baseline and annual visits. Self-reports of anti-VEGF injections were collected., Main Outcome Measures: Principal cause of BCVA of 20/200 or worse at 2 years, detected on fundus photography grading., Results: Of the 594 eligible eyes, the number with BCVA of 20/200 or worse at 2 years was 56 (9.4%). Mean BCVA was 14.9 letters (standard deviation [SD], 12.3 letters; Snellen equivalent, 20/500), versus 70.1 letters (SD, 12.8 letters; Snellen equivalent, 20/40) in the other group. Of the 55 eyes with fundus photography available at 2 years, 33 (60.0%) had central macular atrophy and 22 (40.0%) had central subretinal fibrosis assessed as the principal cause for poor vision. The group with poor BCVA had a higher proportion of non-White participants (8.9% vs. 1.7%; P = 0.006), lower BCVA 2 years earlier (mean, 38.0 letters [SD, 26.7 letters; Snellen equivalent, 20/160] vs. 71.8 letters (SD, 11.9 letters; Snellen equivalent, 20/40]; P < 0.0001), higher proportion with macular atrophy 2 years earlier (26.8% vs. 12.3%; P = 0.003), higher proportion with macular hemorrhage (25.5% vs. 13.2%; P = 0.014), and fewer anti-VEGF injections (7.6 vs. 10.2; P = 0.001)., Conclusions: Visual acuity data and fundus photography were obtained in a clinical trial environment, but were related to anti-VEGF therapy given in routine clinical practice. At 2 years after starting anti-VEGF therapy, almost 1 in 10 eyes showed BCVA at the level of legal blindness. From fundus photography grading, the cause of poor vision appeared to be macular atrophy in 60% and subretinal fibrosis in 40%. These data may be useful in understanding the long-term limits to good vision in nAMD., (Published by Elsevier Inc.)

Stickler syndrome is known to cause visual handicap due to the high incidence of retinal detachment. We aim to present an unusual case of a child with Stickler syndrome who had progressive visual loss secondary to atrophy of the outer retinal layers not associated with retinal detachment. This is a descriptive case report of a 9-year-old child with ocular history of high myopia who presented to our institution with suboptimal visual acuity in both eyes. After 2 years of follow up, he developed unilateral progressive visual loss with marked atrophy of the outer retinal layers and peripheral vascular leakage. Such a presentation has not been previously described in the literature to the best of our knowledge.

For normally sighted readers, word neighborhood size (i.e., the total number of words that can be formed from a single word by changing only one letter) has a facilitator effect on word recognition. When reading with central field loss (CFL) however, individual letters may not be correctly identified, leading to possible misidentifications and a reverse neighborhood size effect. Here we investigate this inhibitory effect of word neighborhood size on reading performance and whether it is modulated by word predictability and reading proficiency. Nineteen patients with binocular CFL from 32 to 89 years old (mean ± SD = 75 ± 15) read short sentences presented with the self-paced reading paradigm. Accuracy and reading time were measured for each target word read, along with its predictability, i.e., its probability of occurrence following the two preceding words in the sentence using a trigram analysis. Linear mixed effects models were then fit to estimate the individual contributions of word neighborhood size, predictability, frequency and length on accuracy and reading time, while taking patients' reading proficiency into account. For the less proficient readers, who have given up daily reading as a consequence of their visual impairment, we found that the effect of neighborhood size was reversed compared to normally sighted readers and of higher amplitude than the effect of frequency. Furthermore, this inhibitory effect is of greater amplitude (up to 50% decrease in reading speed) when a word is not easily predictable because its chances to occur after the two preceding words in a specific sentence are rather low. Severely impaired patients with CFL often quit reading on a daily basis because this task becomes simply too exhausting. Based on our results, we envision lexical text simplification as a new alternative to promote effective rehabilitation in these patients. By increasing reading accessibility for those who struggle the most, text simplification might be used as an efficient rehabilitation tool and daily reading assistive technology, fostering overall reading ability and fluency through increased practice.

Purpose: The purpose of this study was to investigate the benefits of vision training with visual evoked potentials (VEP) biofeedback in amblyopia after the critical period in 8 to 17-year (11.5 ± 3.1) old children., Methods: Ten participants with monocular amblyopia after the critical period underwent a 10-week, 20-session vision training program with the Retimax Vision Trainer device. During each session, the participants were instructed to be as focused as possible onto the fixation point in the middle of the screen. The size of the fixation point and the pitch of the background sound were changing according to VEP parameters and thus provided the participants real-time feedback of their visual performance., Results: The mean BCVA improvement across our group was 0.12 LogMAR (p < 0.01). There was also a significant increase in contrast sensitivity to the FACT chart across all spatial frequencies (all p < 0.05). Electrophysiologic data revealed higher steady-state visual evoked potentials (SS-VEP) amplitudes and correspondingly lower fixation point values in the last 2 weeks of training compared to the first 2 weeks (both p < 0.01). Due to unexplainably low VEP amplitude levels in later trainings compared to those in the beginning in two participants, we have not found a significant correlation between the increase in BCVA and the increase in SS-VEP amplitude (p = 0.88). At the follow-up at 2 and 12 months following the end of training, both BCVA and contrast sensitivity remained within the levels achieved at the end of training. In some participants, however, no improvement of BCVA was observed., Conclusions: The tested vision training approach demonstrates modest but stable improvement of psychophysical parameters as well as objective characteristics in amblyopia after the critical period. Real-time SS-VEP can be used as an objective parameter to monitor participants' attention during vision training stimulation.

Two fundamental constraints limit the number of characters in text that can be displayed at one time-print size and display size. These dual constraints conflict in two important situations-when people with normal vision read text on small digital displays, and when people with low vision read magnified text. Here, we describe a unified framework for evaluating the joint impact of these constraints on reading performance. We measured reading speed as a function of print size for three digital formats (laptop, tablet, and cellphone) for 30 normally sighted and 10 low-vision participants. Our results showed that a minimum number of characters per line is required to achieve a criterion of 80% of maximum reading speed: 13 characters for normally sighted and eight characters for low-vision readers. This critical number of characters is nearly constant across font and display format. Possible reasons for this required number of characters are discussed. Combining these character count constraints with the requirements for adequate print size reveals that an individual's use of a small digital display or the need for magnified print can shrink or entirely eliminate the range of print size necessary for achieving maximum reading speed., Competing Interests: The authors declare no competing interest., (Copyright © 2020 the Author(s). Published by PNAS.)

Age-related macular degeneration (AMD) is a progressive and degenerative disorder of the macula. In advanced stages, it is characterized by the formation of areas of geographic atrophy or fibrous scars in the central macula, which determines irreversible loss of central vision. These patients can benefit from visual rehabilitation programmes with acoustic "biofeedback" mechanisms that can instruct the patient to move fixation from the central degenerated macular area to an adjacent healthy area, with a reorganization of the primary visual cortex. In this prospective, comparative, non-randomized study we evaluated the efficacy of visual rehabilitation with an innovative acoustic biofeedback training system based on visual evoked potentials (VEP) real-time examination (Retimax Vision Trainer, CSO, Florence), in a series of patients with advanced AMD compared to a control group. Patients undergoing training were subjected to ten consecutive visual training sessions of 10 min each, performed twice a week. Patients in the control group did not receive any training. VEP biofeedback rehabilitation seems to improve visual acuity, reading performances, contrast sensitivity, retinal fixation and sensitivity and quality of life in AMD patients.

Purpose: To develop age-appropriate extensions of a patient-reported outcome measure for capturing the functional impact of visual impairment on daily activities of children and young people aged 8 up to 18 years., Design: Questionnaire development and validation study., Methods: Pediatric Ophthalmology departments at Great Ormond Street Hospital and Moorfields Eye Hospital, and, in the final study phase, 20 further UK hospitals. Children and young people (aged 6-19 years) with visual impairment (acuity of the logarithm of the minimum angle of resolution (LogMAR) worse than 0.50 in the better eye) due to any cause but without significant non-ophthalmic impairments. We used our prototype FVQ&#95;CYP for 10-15 year olds as the foundation. Twenty-nine semi-structured interviews confirmed relevance of existing, and identified new, age-specific items. Twenty-eight cognitive interviews captured information regarding comprehensibility and format. The FVQ&#95;Child (8-12 years) and FVQ&#95;Young Person (13-18 years) were evaluated with a national sample of 113 children and 96 young people using Rasch analysis., Results: Issues emerging from interviews with children and young people were largely congruent with those elicited originally with 10-15 year olds. The 28-item FVQ&#95;Child and 38-item FVQ&#95;Young Person versions have goodness-of-fit statistics within the interval 0.5, 1.5 and person separation values of 5.87 and 6.09 respectively. Twenty-four overlapping "core" items enabled their calibration on the same measurement scale. Correlations with acuity (r = 0.47) demonstrated construct validity., Conclusions: The FVQ&#95;C and FVQ&#95;Young Person are robust age-appropriate versions of the FVQ&#95;CYP which can be used cross-sectionally or sequentially/longitudinally across the age range of 8 up to 18 years in clinical practice and research., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Macular degeneration (MD), a retinal disease affecting central vision, represents the leading cause of visual impairment in the Western world, and MD patients face severe limitations in daily activities like reading and face recognition. A common compensation strategy adopted by these patients involves the use of a region in the spared peripheral retina as a new fixation spot and oculomotor reference (preferred retinal locus, or PRL). Still, peripheral vision is characterized by poorer visual acuity, fixation stability, and larger crowding zones that further hinder processes like object recognition, visual search, and reading. Perceptual learning (PL) has been successfully used to improve visual acuity in mild visual conditions (e.g., presbyopia, amblyopia and myopia), but results in MD are less clear, often showing limited generalization of learning, unlike what is observed in a healthy population. A possible reason is the suboptimal fixation in the PRL that might prevent patients from processing the briefly presented training stimuli. Following this hypothesis, we trained five MD patients and four age- and eccentricity-matched controls with a protocol that combined contrast detection and a task previously used to train fixation stability. Results showed transfer of learning to crowding reduction, reading speed, and visual acuity in both MD patients and controls. These results suggest that in the case of central vision loss, PL training might benefit from the integration of oculomotor components to optimize the effect of training and promote transfer of learning to other visual functions.