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Purpose: This study explores the initial views of people with age-related macular degeneration towards wearable electronic vision enhancement systems. Methods: Ten adults with age-related macular degeneration participated in semi-structured interviews, which were analysed using reflexive thematic analysis. Results: Four themes were identified. Firstly, participants spoke of the wide-ranging impact of sight loss and how current helpful coping strategies still had significant limitations, affecting their desire to seek new solutions. The second theme showed that "other people" offered welcomed support with existing electronic coping solutions and are needed to provide suitable advice and training. However, "other people" limited the acceptability of using new solutions in public places. The third theme captured participants' desire for a wearable aid providing image magnification and enhancement over a range of distances. The final theme covered the reality of some current wearable technology, perceived as heavy, enclosing, or strange in appearance. Appearance caused some to lose interest in use, although others reframed the devices' desired usefulness to solo and sedentary activities. Conclusion: This population are interested in the potential benefits of wearable electronic vision enhancement systems. More work is needed to understand the suitability of current solutions due to participant concerns about training, appearance and performance. IMPLICATIONS FOR REHABILITATION: A device that offers image enhancement and variable magnification in a hands-free, wearable form is very desirable to people with age-related macular degeneration. Some potential users are not seeking new solutions to well-described problems, which may be a useful coping strategy but alternatively may be motivated by fear of the unknown, financial worries, or concerns about appropriate training. The weight and appearance of some of the current wearable electronic vision enhancement systems are not immediately appealing and would stop some from proceeding with a performance trial. After viewing the current devices, the desirable times to use a wearable electronic vision enhancement system may be reframed by users to focus predominately on sedentary tasks taking place in isolation at home. [ABSTRACT FROM AUTHOR]

Purpose: Recreational runners who need refractive visual correction will need to choose the type of visual correction (spectacles, contact lenses, or no correction) to wear when running. The prevalence of correction choices and distinguishing demographic features associated with these choices of correction were investigated. Methods: A 26-item online questionnaire covering demographics, running habits, and visual corrections used was answered by 941 people. Participants were aged 18 years or older, considered themselves a recreational runner and reported needing refractive correction for everyday life. Bivariate analyses and binary logistic regression were used to determine the variables independently associated with including or avoiding types of correction for running. Results & conclusions: Participants ran an average of 3.8times, 3.6hours, and 33.4km per week. Running habits were not associated with type of visual correction, suggesting that visual correction does not present a barrier to participating in recreational running. Solely using spectacles for running was the most common choice (38.8%) and they were worn for running at least sometimes by 65.8%. Fewer people wore spectacles for running than for general purposes (98.9%), suggesting spectacles have limitations for running. Spectacle wear for running was significantly associated with not having contact lenses available and longer duration of wearing visual correction. Running without correction was a common choice, with 15.5% of the sample only running without correction, and 26.2% running at least sometimes without their visual correction. Not wearing correction was significantly associated with not having contact lenses, a shorter duration of wearing visual correction, and a lower myopic refractive error. Contact lenses were the sole correction for running for 15.6% and were worn for running at least sometimes by 40.5%. Contact lenses were significantly more likely to be used by women and younger runners. Signposting runners to contact lenses if this has not previously been considered is recommended. [ABSTRACT FROM AUTHOR]

Abstract Background Vision in people with autism spectrum conditions (ASC) is reported to be different from people without ASC, but the neural level at which the differences begin to occur is not yet known. Here we examine two variants of a vernier acuity task to determine if differences are evident in early visual processing. Findings Abutting and separated vernier acuity was assessed in 16 people with ASC and 14 matched controls. In controls, abutting and separated thresholds were unrelated (r = 0.13, p = 0.65), suggesting thresholds are determined by two separate mechanisms. In contrast, the abutting and separated thresholds of ASC observers were strongly correlated (r = 0.88, p < 0.0001), with separated thresholds tending towards being superior to those of controls [t(28) = −2.46, p = 0.02]. Conclusions The findings suggest the mechanisms employed by ASC observers in separated vernier tasks are different to those of controls. This psychophysical evidence suggests that visual differences in ASC may begin at an early cortical stage of visual processing.

Introduction: Age‐related macular degeneration (AMD) is the most common cause of irreversible visual impairment in the United Kingdom. It has a wide‐ranging detrimental impact on daily living, including impairment of functional ability and quality of life. Assistive technology designed to overcome this impairment includes wearable electronic vision enhancement systems (wEVES). This scoping review assesses the usefulness of these systems for people with AMD. Methods: Four databases (Cumulative Index to Nursing and Allied Health Literature, PubMed, Web of Science and Cochrane CENTRAL) were searched to identify papers that investigated image enhancement with a head‐mounted electronic device on a sample population that included people with AMD. Results: Thirty‐two papers were included: 18 studied the clinical and functional benefits of wEVES, 11 investigated use and usability and 3 discussed sickness and adverse effects. Conclusions: Wearable electronic vision enhancement systems provide hands‐free magnification and image enhancement producing significant improvements in acuity, contrast sensitivity and aspects of laboratory‐simulated daily activity. Adverse effects were infrequent, minor and spontaneously resolved with the removal of the device. However, when symptoms arose, they sometimes persisted with continued device usage. There are multi‐factorial influences and a diversity of user opinions on promotors to successful device use. These factors are not exclusively driven by visual improvement and incorporate other issues including device weight, ease of use and inconspicuous design. There is insufficient evidence of any cost–benefit analysis for wEVES. However, it has been shown that a user's decision to make a purchase evolves over time, with their estimates of cost falling below the retail price of the devices. Additional research is needed to understand the specific and distinct benefits of wEVES for people with AMD. Further patient‐centred research should assess the benefits of wEVES in user‐led activities when directly compared with alternative coping strategies, allowing professionals and users to make better prescribing and purchasing decisions. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to determine whether a clinician can assess critical print size (CPS) and/or reading fluency by listening to a visually impaired patient reading aloud across a range of print sizes on an MNREAD chart, rather than needing to plot and analyse reading speed data as a function of print size. Methods: Fifty‐six low vision participants were audio‐recorded reading an MNREAD chart under standard conditions. Two experienced raters listened to the recordings and made judgments of the CPS (logMAR), and of the level of reading fluency achieved at large print sizes on a 4‐point rating scale. Reading times were plotted as a function of print size to determine the CPS as the smallest print size that supported the participant's maximum reading speed (MRS) by inspection, and the MRS as the mean reading speed across print sizes including, and larger than, the CPS. Results: Listened CPS judgments made for each rater were slightly larger than the CPS values obtained by inspection (mean differences 0.04logMAR (p = 0.06), 0.08logMAR (p < 0.01); limits of agreement (LoA) ±0.28logMAR, ±0.39logMAR, respectively). CPS judgments were consistent both between raters (mean difference 0.04logMAR [p = 0.18]; LoA ±0.42logMAR) and between two judgments made by each rater (mean differences 0.00logMAR (p = 1.0), 0.03logMAR (p < 0.05); LoA ±0.23logMAR, ±0.17logMAR). Reading fluency could be categorised as 'functional' (MRS > 80 wpm) or 'non‐functional' (MRS < 80 wpm) with a sensitivity of 88%–90% and a specificity of 100%. Conclusions: Experienced raters listening to a patient reading an MNREAD chart can determine a clinically useful estimate of critical print size and can discriminate maximum reading speeds that are above and below that likely to provide sustained reading ability. Listening to a patient reading an MNREAD chart is an option for the low vision clinician's armoury of assessments. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to determine what a person with vision loss considers a 'comfortable' print size to read, and examine whether this reflects any of three currently used parameters for identifying print size required for sustained reading tasks: minimum size to achieve maximum reading speed (the critical print size (CPS)); minimum size for functional reading at 80 wpm and/or a size that is double the reading acuity (representing an acuity reserve of 2:1). Methods: Forty‐seven participants entering low vision rehabilitation (mean age 77 years, 24 with macular degeneration) were assessed using MNREAD charts to determine reading acuity, maximum reading speed, CPS and the minimum size allowing functional (80 wpm) reading. Comfortable print size was assessed by asking participants to identify 'the smallest print size that you would find comfortable using' on the MNREAD chart. Results: There was little difference between comfortable print size and CPS (mean difference 0.05 logMAR (SD 0.18); p = 0.08, limits of agreement ±0.35 logMAR), and no trend for the difference between values to differ across the functional range. Size for functional reading could only be assessed for 41 participants, and the difference between this and comfortable print size varied across the functional range. Comfortable print size was consistently smaller than twice the reading acuity size (mean difference 0.11 logMAR (SD 0.17); p < 0.001), with an average acuity reserve of 1.74:1. Conclusions: Asking people with visual impairment to identify a print size that is comfortable to read provides a print size similar to the CPS. This can be used as a guide in selecting magnification for sustained reading without having to undertake further analyses. Identification of perceived comfortable print size may offer a time‐efficient clinical method of estimating magnification requirements, and be relevant for undertaking effective remote consultations. [ABSTRACT FROM AUTHOR]

Purpose: Longitudinal changes in priority rehabilitation needs, vision‐related activity limitation and importance of visual goals were evaluated in a sample of people with a visual impairment over a year following entry to low vision rehabilitation services in England. Methods: Participants were adults with newly registered visual impairment within Leicestershire. Priority scores, indicating the level of rehabilitative need, were determined from the importance and difficulty scores of the 48 goals of the Participation and Activity Inventory (PAI). Rasch analysis of the difficulty and importance scores examined activity limitation and importance separately. PAI outcome measures were assessed on entry to rehabilitation services and at 4 and 12 months thereafter. Results: Forty‐eight participants (mean age 74.2, SD 14.1 years) completed three visits. Overall, there was a statistically significant reduction in the perceived need for rehabilitation over time (p < 0.001, ηp2 = 0.29), driven by reduced perceived difficulty (p < 0.001, ηp2 = 0.32) but stable importance (p = 0.73) of goals, with most change occurring between baseline and 4 months. PAI goals with greatest rehabilitative need at study entry were reading, mobility and writing, and these remained of highest priority over time. The greatest priority score decrease was for the goal 'Hobbies and crafts'. The largest decrease in importance was for 'Mobility outdoors', whereas 'Relationship with loved ones' increased most. Conclusions: Despite a decline in the perceived need for rehabilitation over the study period, there remains a need for continued support and intervention at 12 months following registration with rehabilitation services, particularly for the key goals of reading, writing and mobility. Early identification and support for individuals' important but difficult goals could prevent such goals being relinquished. Goals concerning relationships and communication became more important over time, indicating that re‐evaluation of needs at follow‐up is necessary to inform ongoing service provision. [ABSTRACT FROM AUTHOR]

Purpose: Vision impairment (VI) may impact a person's functional ability resulting in a loss of independence, anxiety, depression, social isolation and reduced quality of life. Caregivers also experience similar problems due to the increased burden placed on them. Support to address these difficulties encountered by those with VI and their caregivers may not always be accessible. An internet‐based intervention may provide more accessible support. The aim of this study was to obtain consensus regarding the content and accessibility features required to design an internet‐based intervention to promote wellbeing for people with VI and their caregivers. Method: A three‐round Delphi review was conducted with a panel of 30 stakeholders. Three stakeholder groups were included, namely individuals with vision loss, experts in the field of vision loss and mental health and carers of individuals with vision loss. Conceptual wellbeing ideas were examined in round 1, the intervention modules and module content were proposed in round 2 and refined in round 3. Results: Consensus of 75% or more was reached to include 18 modules into the intervention. These were divided into seven sections: understanding vision loss, emotional wellbeing, functional wellbeing, social wellbeing, physical wellbeing, wellbeing for carers and maintaining wellbeing. The accessibility features deemed most important were font size, colour and contrast options, compatibility with low vision aids and layout of the intervention. Conclusions: The Delphi process positively informed the design of an internet‐based intervention for individuals with acquired VI and their caregivers. Suggestions provided by stakeholders should now be incorporated into the intervention. Future evaluation of efficacy and cost‐effectiveness of such an intervention are necessary. [ABSTRACT FROM AUTHOR]

Classification within the sport of vision impairment (VI) shooting is based upon the athlete's visual function. This study aimed to determine whether more than one class of competition is needed within VI shooting on the basis of visual field loss. Qualification scores of 23 elite athletes were obtained at World Championship events in prone and standing shooting disciplines. Visual field data were obtained from classification data and from assessment at events. A standardized scoring protocol determined whether athletes had function (≥10 dB) or no function (<10 dB) at locations between 0–60 degrees eccentricity along 10 meridia. Visual field function was not associated with shooting performance in prone or standing disciplines (p > 0.05). Having measurable visual field function beyond 30 degrees made no difference to athletes' ability to shoot competitively in prone (p = 0.65) or standing disciplines (p = 0.47), although a potential impact on qualification was observed in the standing discipline. There was no evidence that loss of visual field function at any specific location adversely affected ability to shoot competitively. There is currently no evidence to consider visual fields in classification within prone or standing VI shooting, although further research is needed as the sport grows. [ABSTRACT FROM AUTHOR]

Revised evidence-based classification criteria introduced for shooting for athletes with vision impairment (VI shooting) suggest that athletes with impaired contrast sensitivity (CS) and visual acuity (VA) should be eligible for inclusion in the sport but should all eligible athletes compete against each other in the same "class" or is more than one class necessary? Twenty-five elite VI shooting athletes took part in the study. Two measures of visual function were assessed under standardized conditions: VA (using an ETDRS logMAR letter chart, and/or a BRVT chart) and CS (using both a Pelli-Robson chart and a Mars number chart). Shooting performance, in both prone and standing events, was measured during an international VI shooting competition. Fourteen of the 25 athletes had measurable VA, and for CS, 8 athletes had measurable function with the Pelli-Robson chart and 13 with the Mars chart. The remaining athletes had function not numerically measurable by the charts and were considered to have no residual vision. There was no indication that shooting performance varied with visual function, and individuals that had residual vision had no advantage over those without vision for either prone or standing shooting. The modifications made to VI shooting, including the use of auditory tones to guide the gun barrel, appear to have successfully rendered the sport equitable for all eligible athletes. Only one class is necessary for athletes. An improved method of measuring CS in athletes with profound VI would be advantageous. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate outcome measures of the Participation and Activity Inventory (PAI) in a sample of adults with acquired visual impairment entering vision rehabilitation. Both Priority Scores, indicating level of rehabilitative need, and Person Measures, indicating goal difficulty, were considered. Methods: Participants were newly registered adults with visual impairment within Leicestershire, United Kingdom. The importance and difficulty of 48 goals of the PAI were assessed, as were demographic factors, clinical visual function (visual acuity, contrast sensitivity, reading function) and psychosocial function (adjustment to visual loss, depression, anxiety and fear of falling). Priority scores were calculated as the product of importance and difficulty of each goal. All questionnaires were Rasch analysed, and person and item measures of perceived difficulty with goals were derived. Results: Sixty people (mean age ± S.D. = 75.8 ± 13.8 years) took part. PAI goals with greatest rehabilitative need were reading (6.82 ± 2.91), mobility outdoors (6.55 ± 3.92), mobility indoors within an unfamiliar environment (5.52 ± 3.93) and writing (5.27 ± 3.02). Greater rehabilitative need was associated with younger age (β = −0.46, p < 0.001), and with higher depressive symptomatology (β = 0.35, p < 0.01; model R2 34%). Goals with greatest difficulty were mending clothing (−1.95 ± 0.35 logits) and hobbies and crafts (−1.32 ± 0.23 logits). Greater difficulty was associated with higher depressive symptomatology (β = 0.39, p < 0.001), lower visual acuity (β = 0.42, p < 0.001) and lower adjustment of visual loss (β = 0.31, p < 0.01; model R2 53%). Conclusions: Key rehabilitation needs for adults at entry to services require both optical and non‐optical interventions. As rehabilitative need was not associated with the level of visual impairment, eyecare professionals should not wait until the end of medical treatment before referral for support. Similarly, rehabilitative need was associated with younger age, indicating the importance to refer younger people with sight loss at an early stage. The use of structured assessment, such as the PAI, ensures goals that have an impact upon quality of life are specifically identified. Depression screening on entry to rehabilitation is relevant as it predicts both perceived difficulty and rehabilitative need. [ABSTRACT FROM AUTHOR]

Purpose: In order to develop an evidence-based, sport-specific minimum impairment criteria (MIC) for the sport of vision-impaired (VI) shooting, this study aimed to determine the relative influence of losses in visual acuity (VA) and contrast sensitivity (CS) on shooting performance. Presently, VA but not CS is used to determine eligibility to compete in VI shooting. Methods: Elite able-sighted athletes (n = 27) shot under standard conditions with their habitual vision, and with their vision impaired by the use of simulation spectacles (filters which reduce both VA and CS) and refractive blur (lenses which reduce VA with less effect on CS). Habitual shooting scores were used to establish a cut-off in order to determine when shooting performance was ‘below expected’ in the presence of vision impairment. Logistic regression and decision tree analyses were then used to assess the relationship between visual function and shooting performance. Results: Mild reductions in VA and/or CS did not alter shooting performance, with greater reductions required for shooting performance to fall below habitual levels (below 87% of normalized performance). Stepwise logistic regression selected CS as the most significant predictor of shooting performance, with VA subsequently improving the validity of the model. In an unconstrained decision tree analysis, CS was selected as the sole criterion (80%) for predicting ‘below expected’ shooting score. Conclusion: Shooting performance is better predicted by losses in CS than by VA. Given that it is not presently tested during classification, the results suggest that CS is an important measure to include in testing for the classification of vision impairment for athletes competing in VI shooting. [ABSTRACT FROM AUTHOR]

Objectives To develop an appropriate method of assessing visual field (VF) loss which reflects its functional consequences, this study aims to determine which method(s) of assessing VF best reflect mobility difficulty. Setting This cross-sectional observational study took place within a single primary care setting. Participants attended a single session at a University Eye Clinic, Cambridge, UK, with data collected by a single researcher (HS), a qualified optometrist. Participants 50 adult participants with peripheral field impairment were recruited for this study. Individuals with conditions not primarily affecting peripheral visual function, such as macular degeneration, were excluded from the study. Primary and secondary outcome measures Participants undertook three custom and one standard binocular VF tests assessing VF to 60°, and also integrated monocular threshold 24-2 visual fields (IVF). Primary VF outcomes were average mean threshold, percentage of stimuli seen and VF area. VF outcomes were compared with self-reported mobility function assessed with the Independent Mobility Questionnaire, and time taken and patient acceptability were also considered. Receiver operating characteristic (ROC) curves determined which tests best predicted difficulty with mobility tasks. Results Greater VF loss was associated with greater self-reported mobility difficulty with all field paradigms (R²0.38-0.48, all P<0.001). All four binocular tests were better than the IVF at predicting difficulty with at least three mobility tasks in ROC analysis. Mean duration of the tests ranged from 1 min 26 s (±9 s) for kinetic assessment to 9 min 23 s (±24 s) for IVF. Conclusions The binocular VF tests extending to 60° eccentricity all relate similarly to self-reported mobility function, and slightly better than integrated monocular VFs. A kinetic assessment of VF area is quicker than and as effective at predicting mobility function as static threshold assessment. [ABSTRACT FROM AUTHOR]

Purpose The aim of this study is to relate areas of the visual field to functional difficulties to inform the development of a binocular visual field assessment that can reflect the functional consequences of visual field loss. Methods Fifty-two participants with peripheral visual field loss undertook binocular assessment of visual fields using the 30-2 and 60-4 SITA Fast programs on the Humphrey Field Analyser, and mean thresholds were derived. Binocular visual acuity, contrast sensitivity and near reading performance were also determined. Self-reported overall and mobility function were assessed using the Dutch ICF Activity Inventory. Results Greater visual field loss (0-60°) was associated with worse self-reported function both overall ( R2 = 0.50; p < 0.0001), and for mobility ( R2 = 0.64; p < 0.0001). Central (0-30°) and peripheral (30-60°) visual field areas were similarly related to mobility function ( R2 = 0.61, p < 0.0001 and R2 = 0.63, p < 0.0001 respectively), although the peripheral (30-60°) visual field was the best predictor of mobility self-reported function in multiple regression analyses. Superior and inferior visual field areas related similarly to mobility function ( R2 = 0.56, p < 0.0001 and R2 = 0.67, p < 0.0001 respectively). The inferior field was found to be the best predictor of mobility function in multiple regression analysis. Conclusion Mean threshold of the binocular visual field to 60° eccentricity is a good predictor of self-reported function overall, and particularly of mobility function. Both the central (0-30°) and peripheral (30-60°) mean threshold are good predictors of self-reported function, but the peripheral (30-0°) field is a slightly better predictor of mobility function, and should not be ignored when considering functional consequences of field loss. The inferior visual field is a slightly stronger predictor of perceived overall and mobility function than the superior field. [ABSTRACT FROM AUTHOR]

It is difficult for visually impaired people (VIPs) to know what rehabilitation services are available that may be of benefit to them. Appropriate services are covered by health, social care and voluntary sectors, with significant differences in the services available in different areas of the UK. The eye care practitioner has an important role, not only in providing optical advice and low-vision aids, but also in signposting patients to those services that go beyond the practitioner's own remit. At a minimum, practitioners should know how to refer their patients to hospital eye service low-vision services, to local-authority sensory service teams, and to local voluntary societies for the visually impaired. Additional providers of relevant services for practitioners to be aware of are discussed, and links to further resources provided. There is a lack of good-quality evidence of the need for low-vision services and of service effectiveness. Such evidence is needed for guiding commissioning decisions regarding provision of future low-vision services. [ABSTRACT FROM AUTHOR]

The measurement of distance visual acuity is the most familiar and most widely used test of visual function. However, this is only one in a battery of tests used in the assessment of patients with visual impairment. A full and comprehensive assessment helps to build a picture of the need and urgency for further treatment, including the provision of rehabilitative interventions and to predict the performance of low-vision devices. This review outlines some of the principal tests and strategies available for the clinical assessment of visually impaired patients that are readily available to practising optometrists. The generic principles of the key visual functions assessed in the low-vision assessment are outlined, together with a critical review of those instruments still currently used within optometric practice which may not yield the most reliable results. Improving the accuracy of visual assessment will improve referral refinement, support decision making and assist in prescribing the most appropriate solutions for visually impaired patients. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the level of vision impairment (VI) that would reduce performance in shooting; to guide development of entry criteria to visually impaired (VI) shooting. Nineteen international-level shooters without VI took part in the study. Participants shot an air rifle, while standing, toward a regulation target placed at the end of a 10 m shooting range. Cambridge simulation glasses were used to simulate six different levels of VI. Visual acuity (VA) and contrast sensitivity (CS) were assessed along with shooting performance in each of seven conditions of simulated impairment and compared to that with habitual vision. Shooting performance was evaluated by calculating each individual's average score in every level of simulated VI and normalizing this score by expressing it as a percentage of the baseline performance achieved with habitual vision. Receiver Operating Characteristic curves were constructed to evaluate the ability of different VA and CS cut-off criteria to appropriately classify these athletes as achieving 'expected' or 'below expected' shooting results based on their performance with different levels of VA and CS. Shooting performance remained relatively unaffected by mild decreases in VA and CS, but quickly deteriorated with more moderate losses. The ability of visual function measurements to classify shooting performance was good, with 78% of performances appropriately classified using a cut-off of 0.53 logMAR and 74% appropriately classified using a cut-off of 0.83 logCS. The current inclusion criteria for VI shooting (1.0 logMAR) is conservative, maximizing the chance of including only those with an impairment that does impact performance, but potentially excluding some who do have a genuine impairment in the sport. A lower level of impairment would include more athletes who do have a genuine impairment but would potentially include those who do not actually have an impairment that impacts performance in the sport. An impairment to CS could impact performance in the sport and might be considered in determining eligibility to take part in VI competition. [ABSTRACT FROM AUTHOR]

Purpose: To understand the emotional difficulties associated with living with the ocular condition Retinitis Pigmentosa, and to examine the functioning of a self-report instrument used to assess this construct. Methods: The difficulty of goals and tasks in the emotional health domain of the Dutch ICF Activity Inventory were rated by 166 people with Retinitis Pigmentosa in a cross-sectional study. Demographic factors were also assessed. Results: Responses to the 23 emotional health tasks were Rasch analysed and could be used to form either one 20 item overview scale with some multidimensionality, or three unidimensional subscales addressing feelings (4 items), communicating visual loss (5 items) and fatigue (7 items). The most difficult individual tasks related to communicating visual loss to other people, and dealing with feelings such as frustration, anxiety and stress. The use of mobility aids and female gender were associated with increased difficulty with emotional health, explaining 19% of the variance in the overview scale. Conclusions: The emotional health domain of the Dutch ICF Activity Inventory is a valid tool to assess emotional difficulties arising from visual loss. Interventions to aid people with Retinitis Pigmentosa deal with emotional difficulties should particularly address communicating vision loss effectively to others and coping with negative feelings. [ABSTRACT FROM AUTHOR]

This paper reviews the current visual acuity standards for UK drivers. These standards have changed in recent years such that car drivers (Group 1) now have two standards to meet: reading a number plate at 20m, and achieving an acuity of 6/12. In the light of these changes, research investigating the effect of uncorrected refractive error and simulated cataract on the ability to meet the visual standards is reviewed, as is the effect of reduced contrast sensitivity on driving. On the basis of these findings, recommendations are made for optometrists regarding how to assess acuity in drivers, and how to use this information when advising patients on their visual fitness to drive. [ABSTRACT FROM AUTHOR]

Background: A comparison was made between letter visual acuity and word acuity at distance and between letter acuity and the minimum word size allowing maximum and fluent reading speeds.Methods: Visual acuities were measured at six metres for 120 participants. Letter acuity was assessed with a logMAR layout chart with Sloan letters displayed with Thomson XPert software. A logMAR layout lowercase word chart was created in PowerPoint using the format of the MNRead near chart, with the font and colours found on United Kingdom motorway signs. Distance letter and word acuity, maximum reading speed, critical print size (CPS) and minimum print size for fluent reading were calculated.Results: Word and letter acuities were significantly correlated (p < 0.001) and showed a statistically (p = 0.049) but not clinically significant mean difference of 0.02 ± 0.09 logMAR. Bland-Altman analysis showed that agreement between charts varied depending on acuity level with word acuity better than letter acuity at levels closer to the driving standard of +0.30 logMAR (6/12). Maximum reading speed was achieved from print sizes 1.5 logMAR lines larger than the letter acuity and fluent reading at 80 words per minute from print sizes 0.06 logMAR larger than the letter acuity.Conclusion: These results allow equivalent lowercase print sizes supporting either functional reading or maximum reading speeds to be calculated based on letter chart acuities at distance. Minimum print sizes allowing either functional or maximum reading speeds are more appropriate than threshold word acuities, where groups of words or short phrases need to be identified, such as when driving. Where a driving vision standard of +0.30 logMAR (6/12) exists, a person just meeting the driving standard should be able to read fluently words on signage in lowercase x-heights equivalent to between +0.29 and +0.30 logMAR. [ABSTRACT FROM AUTHOR]

The article presents the result of the survey involving the functions of contrast sensitivity (CS) and the reason why CS is used extensively. It introduces a brief description of CS wherein its contrast threshold values change from a minimum of zero to maximum of one. It also highlights various letter charts which include the Pelli-Robson and Low contrast Bailey-Lovie.

Optometrists are required to refer patients with any abnormality of the eye, excluding normal changes due to age, to a General Practitioner. It can be difficult to decide when a cataract ceases to be a normal age-related change and becomes an ocular abnormality. This questionnaire-based study examines the cnteria adopted by Optometrists and GPs for referring patients with cataract and compares this to the referral criteria suggested by Ophthalmologists. For all professions, the main factors influencing referral are visual acuity, subjective visual impairment and the need to drive. Optometrists and GPs generally refer patients with cataract at a VA level of 6/18-6/24, whilst most Ophthalmologists would be willing to see patients with cataract at a VA of 6/9-6/12. However, Ophthalmoiogists report that sometimes patients are referred too soon, regardless of their acuity lever, because the patient is not yet impaired by their level of vision or does not want surgery. Suggestions for improvements in the referral of cataract are discussed. It is important for Optometrists to make clear whether a letter to a GP is for information only or for referral. If referral is warranted, information in addition to acuity will assist an Ophthalmologist in prioritizing appointments, including age, occupation, brief description of disability and the need to drive without contravening any laws. [ABSTRACT FROM AUTHOR]

The rate of change of visual performance with increasing eccentricity of fixation is known to be task dependent. In order to examine eccentricity-related changes in visual performance when a combination of two different factors influence thresholds, visual acuity in the presence of flanking elements was investigated across the visual field. Interference zones increased in extent with eccentricity at a much faster rate than did resolution thresholds. E2 values, quantifying the eccentricity related magnification required, were 1-2° for resolution and 0.1 - 0.2° for spatial interference. E2 values for resolution in the presence of flanks depended on the proximity of the flanks and their 'weighting' in the task. From the results, the magnitude and extent of spatial interference across the visual field can be described quantitatively. Further, the results serve as an example of how observed variations in peripheral threshold gradients might be achieved as a combination of underlying factors with different E2 values. [ABSTRACT FROM AUTHOR]

Static differential light thresholds were measured as a function of stimulus size (Goldmann sites I-V) along four visual field meridia (75, 165, 255 and 345°) with the Humphrey Field Analyzer 640. Data were obtained for both young (n = 10, age 23.6 ± 2.9 years) and elderly (n = 10, age 72.0 ± 5.2 years) normal subjects. The resulting peripheral spatial summation curves could be equated to the foveal data simply by a change in size scale, which increased linearly with eccentricity. E[2sub], values, expressing the eccentricity at which stimulus size must double for performance to remain comparable to the fovea, were in the order of 3-9°. Whilst the rate of scale change is approximately the same for both young and elderly observers, differences in performance can be explained by a combination of lower sensitivity and a bias in sensitivity towards larger stimulus sizes with increasing age. [ABSTRACT FROM AUTHOR]

PURPOSE. Performance on positional acuity tasksexhibits marked resistance to the effects of optical image degradation. Thisplaces positional acuity tasks in a unique position for psychophysical examinationof the effects of age upon visual performance because any observed age-relatedchanges reflect losses in retinal/neural function. One positional acuity taskwith important consequences for "real-world" vision is spatial interval discrimination,a task in which the subject is required to detect changes in the size of thegap between two objects. In the present study we examine spatial intervaldiscrimination in young and elderly observers as a function of separationand eccentricity. METHODS. Stimuli were two Gaussian-modulated luminance patches placed sideby side around an imaginary iso-eccentric arc in the upper visual field, allowingeccentricity and separation to be varied independently. Changes in separationwere achieved by moving the stimuli around the arc, while eccentricity wasvaried by changing the radius of the arc. Thresholds were obtained for healthyyoung and elderly observers using a forced-choice method of constants at twoeccentricities (1.25° and 10°) and five separations. RESULTS. When thresholds, expressed as Weber fractions, are plotted asa function of the geometric ratio of the stimuli (separation/eccentricity)the data from the young and elderly groups collapse to a single function.Performance is independent of age and eccentricity, and depends only on thegeometric ratio of the stimuli. CONCLUSIONS. No effect of age was found for spatial intervaldiscrimination. Our results suggest that spatial interval discrimination belongsto the wider group of positional acuities whose neural substrates are unaffectedby ageing. [ABSTRACT FROM AUTHOR]

Purpose: Wearable electronic low vision enhancement systems (wEVES) improve visual function but are not widely adopted by people with vision impairment. Here, qualitative research methods were used to investigate the usefulness of wEVES for people with age-related macular degeneration (AMD) after an extended home trial., Methods: Following a 12-week non-masked randomised crossover trial, semi-structured interviews were completed with 34 participants with AMD, 64.7% female, mean age 80.2 (±6.0) years, mean distance visual acuity 0.81logMAR (±0.32). Reflexive thematic analysis was used to analyse the data., Results: Four themes were developed: (i) early positivity and potential; (ii) you're not good enough: performance barriers of the device; (iii) you're annoying: practicality barriers of the device and (iv) we can fix this together. First, participants expressed joy in an aesthetically appealing device perceived as potentially enabling, different and complementary to their current solutions. Imagined usefulness included not only reading, shopping and television but also resuming abandoned hobbies. The second theme captured performance barriers that restricted numerous activities but were most acutely noted with manipulation tasks. Barriers included image quality, screen size and short-lived adverse effects. The third theme conveyed the multiple practical challenges that caused annoyance, preventing imagined usage even when performance appeared superior to other solutions. Slow start-up times and the inability to use wEVES dynamically prevented integration within users' lifestyles. The final theme reflected that wEVES remained a desirable concept, but future iterations require inclusive design methodology to ensure development is directed by consumers' needs., Conclusions: Performance and practicality barriers limit the usefulness of a device initially seen as desirable. Current devices do not align with users' requirements for flexible use, even when performance is good. Improvements in technology may solve performance barriers, but these changes must be inclusively designed and evaluated to ensure the device integrates more successfully into the lives of users with AMD., (© 2025 The Author(s). Ophthalmic and Physiological Optics published by John Wiley & Sons Ltd on behalf of College of Optometrists.)

Significance: Evaluating the visual challenges and refractive correction solutions of presbyopic orienteers identifies features of relevance to optometric management of the visual needs of active presbyopes., Purpose: Orienteering is a unique sport requiring visual clarity at a range of viewing distances and has a high proportion of presbyopic participants. This study evaluates the vision corrections used by presbyopic orienteers, specifically aiming to characterize the prevalence of different vision correction options used and to explore the strengths and limitations of different vision correction solutions., Methods: Orienteers 40 years or older completed an online questionnaire consisting of multiple-choice questions covering personal demographics, orienteering participation, and visual corrections worn in everyday life and for orienteering. Free-text questions asked for further information about the corrections used and advice received from eye care practitioners were analyzed using content analysis., Results: There were 469 respondents (195 women, 274 men; median age category, 55 to 59 years). For the 187 people without distance refractive correction, the most frequent corrections for orienteering were "off the shelf" reading spectacles (n = 95) or use of a compass magnifier (n = 24), and for the 277 people with distance refractive correction, they were progressive addition spectacles (n = 96) and monovision contact lenses (n = 63). The main visual challenges faced by orienteers were seeing map detail, lens obstruction from fogging and rain, and difficulty orienteering in low light in the daytime. An ideal correction needed to provide visual clarity for both map and terrain. No visual correction type consistently addressed all challenges. Orienteers valued personalized discussion with eye care practitioners to address their needs., Conclusions: Optimal visual corrections for presbyopic orienteers are individual, but higher reading additions to clarify map detail, contact lenses to avoid lens obstruction, additional light, and solutions that provide clear vision at all viewing distances while avoiding the reading add blurring the ground at the orienteer's feet should be considered. Personalized care is necessary to optimize visual correction solutions., 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.)

Purpose: Comfortable print size (CfPS) has been proposed as a clinical alternative to deriving critical print size (CPS) in the assessment of reading function of vision-impaired patients. This study aimed to assess the repeatability of CfPS and to compare assessment duration and values to CPS measures and acuity reserves., Methods: Thirty-four adults with vision impairment had their reading function assessed. Two assessments of CfPS were made by asking, "What is the smallest print size that you would find comfortable using?" Reading parameters including CPS were determined using the MNREAD card chart and MNREAD app., Results: CfPS was quicker to assess (mean ± SD, 144 ± 77 seconds) than the MNREAD card (231 ± 177 seconds) or app (285 ± 43 seconds). Within-session repeatability of CfPS showed no significant bias or variation across the functional range and limits of agreement (LoA) of ±0.09 logMAR. CfPS values were 0.10 logMAR larger than card CPS values, but no different from app CPS values, with LoA of ±0.43 to 0.45 logMAR. Acuity reserve (comparing CfPS to card reading acuity) was 1.9:1 on average, with a maximum of 5.0:1., Conclusions: CfPS offers a quick, repeatable, and individualized clinical measure of the print size required for sustained reading that reflects CPS values obtained by more traditional measures., Translational Relevance: CfPS is an appropriate clinical measure of reading function to use in determining the magnification requirements of vision impaired patients for sustained reading tasks.

Purpose: Investigate the visual search strategy of individuals with retinitis pigmentosa (RP) when negotiating a floor-based obstacle compared with level walking, and compared with those with normal vision., Methods: Wearing a mobile eye tracker, individuals with RP and normal vision walked along a level walkway or walked along the walkway negotiating a floor-based obstacle. In the level walking condition, tape was placed on the floor to act as an object attracting visual attention. Analysis compared where individuals looked within the environment., Results: In the obstacle compared with level walking condition: (1) the RP group reduced the length of time and the number of times they looked Ahead, and increased the time and how often they looked at features on the ground (Object and Down, P < 0.05); and (2) the visual normal group reduced the time (by 19%) they looked Ahead (P = 0.076), and increased the time and how often they looked at the Object (P < 0.05). Compared with the normal vision group, in both level walking and obstacle conditions, the RP group reduced the time looking Ahead and looked for longer and more often Down (P < 0.05)., Conclusions: The RP group demonstrated a more active visual search pattern, looking at more areas on the ground in both level walking and obstacle crossing compared with visual normals. This gaze strategy was invariant across conditions. This is most likely due to the constricted visual field and inability to rely on inferior peripheral vision to acquire information from the floor within the environment when walking.

Background: To assess the cross-sectional association between self-rated eyesight and physical activity behaviour in a large general population sample of older English adults., Methods: Analyses of data from the English Longitudinal Study of Ageing. Participants provided information on self-rated eyesight (categorised as: excellent/very good/good/fair-poor) and their own physical activity levels (categorised as: inactive/moderate only at least 1/week, vigorous at least 1/week). Associations between self-rated eyesight and physical activity levels were examined using logistic regression., Results: A total of 6634 participants (mean age 65.0±9.2 years) were included in the analyses. In adjusted logistic regression models, those with fair-poor and good eyesight were significantly more likely to be inactive than those who reported excellent eyesight (OR 2.07, 95% CI 1.58 to 2.72; OR 1.59, 1.27 to 1.99, respectively)., Conclusion: In this sample of older English adults, those with self-rated fair-poor vision were over twice as likely to be physically inactive than those who reported having excellent vision. When consistent data have emerged, interventions to increase physical activity in those who have poor eyesight are needed., Competing Interests: Competing interests: None declared.