Principles of modern low vision rehabilitation

The multiple mediating effects of vision-specific factors and depression on the association between visual impairment severity and fatigue: a path analysis study

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.

Ophthalmic rehabilitation in oncology care

Ophthalmic rehabilitation refers to the multidisciplinary approach to restoring, maximizing, and preserving the visual function and quality of life for patients affected by ocular manifestations of cancer or its treatments. Besides its approach to low vision, ophthalmic rehabilitation also encompasses a series of reconstructive interventions to mitigate anatomic deficits that may interplay with visual impairment. A gamut of oncologic conditions may result in ocular disabilities, including primary intraocular tumours, secondary metastases, or adverse effects of systemic therapies such as chemotherapy, radiation, and surgery. Methods of ophthalmic rehabilitation are evolving constantly and involve the prescription of optical aids and adaptive technologies to enhance remaining vision, as well as supportive training and counselling to address psychosocial effects. Although studies in low vision have mostly covered aspects of rehabilitation in inherited and degenerative eye conditions, ophthalmic rehabilitation within the context of cancer carries specificities that have been poorly explored in the literature on ophthalmology and oncology. This review aims to build on the trends of low vision management, ocular oncology treatments, orbital reconstructive surgery, and visual therapy to revise the published rationale behind evaluating and managing patients facing debilitating ocular sequelae as the result of cancer.

Identifying causes of vision loss and assistive technology needs among patients attending rehabilitation clinic of a tertiary care center in North India

PURPOSE

Investigating the causes of visual loss and the best corrected visual acuity (BCVA) is crucial for identifying avoidable eye problems and planning appropriate rehabilitation and assistive technology (AT) services. The study aimed to identify various causes of vision loss and determine AT required for vision rehabilitation (VR).

METHODS

The electronic records of patients who attended the VR clinic at a tertiary eyecare for the past 2 years were reviewed. Information such as demographics, BCVA, and causes of visual impairment were retrieved from the records. BCVA was categorized into better than or equal to 1/60 and less than <1/60 for AT services.

RESULTS

In total, 1723 patients, mostly male (71.2%), visited the rehabilitation clinic from 2018 to 2019. Around 58.6% of patients belonged to the age group 16-49 years, whereas 25.6% were less than 15 years old. The most frequent eye problems were retinal disorders (63.5%), followed by retinitis pigmentosa (15.2%) and rod-cone dystrophy (4.7%). In contrast, congenital disorders were the most common cause of vision loss among younger groups. Approximately 36.0% of patients had <1/60 blindness and 16.6% had ≥1/60. Around 17.1% of patients would benefit from large prints (near vision acuity N18-N12).

CONCLUSION

Early detection and timely management will prevent a significant proportion of patients from developing irreversible vision loss. Around one-third of patients would benefit from visual substitution AT.

The complex relation between visual complaints and decline in visual, visuoperceptual and cognitive functions in people with multiple sclerosis

People with multiple sclerosis (pwMS) report many different visual complaints, but not all of them are well understood. Decline in visual, visuoperceptual and cognitive functions do occur in pwMS, but it is unclear to what extend those help us understand visual complaints. The purpose of this cross-sectional study was to explore the relation between visual complaints and decline in visual, visuoperceptual and cognitive functions, to optimize care for pwMS. Visual, visuoperceptual and cognitive functions of 68 pwMS with visual complaints and 37 pwMS with no or minimal visual complaints were assessed. The frequency of functional decline was compared between the two groups and correlations were calculated between visual complaints and the assessed functions. Decline in several functions occurred more frequently in pwMS with visual complaints. Visual complaints may be an indication of declined visual or cognitive functioning. However, as most correlations were not significant or weak, we cannot infer that visual complaints are directly related to functions. The relationship may be indirect and more complex. Future research could focus on the overarching cognitive capacity that may contribute to visual complaints. Further research into these and other explanations for visual complaints could help us to provide appropriate care for pwMS.

Predictors for work participation of people with visual impairments: A systematic review and meta-analysis

INTRODUCTION

The aim of this systematic review and meta-analysis was to assess factors associated with work participation in people with visual impairments and to explore how these factors may have changed over time.

METHOD

A comprehensive search of PubMed, Embase.com, EBSCO/APA PsycInfo, EBSCO/CINAHL and EBSCO/ERIC from database inception to 1 April 2022 was performed. We included studies with cross-sectional design, case-control, case-series or cohort design, involving visually impaired working-age adults with at least moderate visual impairment, and evaluated the association between visual impairment and work participation. Studies involving participants with deaf-blindness or multiple disabilities were excluded. We assessed study quality (Newcastle-Ottawa Scale [NOS]), examined between-study heterogeneity and performed subgroup analyses. The study protocol was registered in PROSPERO, CRD42021241076.

RESULTS

Of 13,585 records, 57 articles described 55 studies including 1,326,091 participants from mostly high-income countries. Sociodemographic factors associated with employment included higher education (odds ratio [OR] 3.34, 95% confidence interval [CI] 2.47 to 4.51, I2 0%), being male (OR 1.59, 95% CI 1.37 to 1.84, I2 95%), having a partner (OR 1.73, 95% CI 1.12 to 2.67, I2 34%), white ethnicity (OR 1.36, 95% CI 1.07 to 1.74, I2 0%) and having financial assistance (OR 0.38, 95% CI 0.26 to 0.55, I2 85%). Disease-related factors included worse visual impairment (OR 0.61, 95% CI 0.46 to 0.80, I2 98%) or having additional disabilities (OR 0.55, 95% CI 0.49 to 0.62, I2 16%). Intervention-related factors included mobility aid utilisation (OR 0.35, 95% CI 0.10 to 1.18, I2 94%). A potential moderating effect of time period and geographical region was observed for some factors. Study quality (NOS) was rated moderate to high.

CONCLUSION

Several sociodemographic and disease related factors were associated with employment status. However, the results should be interpreted with caution because of overall high heterogeneity. Future research should focus on the role of workplace factors, technological adjustments and vocational rehabilitation services on work participation.

Establishing a method to estimate the effect of antimyopia management options on lifetime cost of myopia

BACKGROUND

Informed decisions on myopia management require an understanding of financial impact. We describe methodology for estimating lifetime myopia costs, with comparison across management options, using exemplars in Australia and China.

METHODS

We demonstrate a process for modelling lifetime costs of traditional myopia management (TMM=full, single-vision correction) and active myopia management (AMM) options with clinically meaningful treatment efficacy. Evidence-based, location-specific and ethnicity-specific progression data determined the likelihood of all possible refractive outcomes. Myopia care costs were collected from published sources and key informants. Refractive and ocular health decisions were based on standard clinical protocols that responded to the speed of progression, level of myopia, and associated risks of pathology and vision impairment. We used the progressions, costs, protocols and risks to estimate and compare lifetime cost of myopia under each scenario and tested the effect of 0%, 3% and 5% annual discounting, where discounting adjusts future costs to 2020 value.

RESULTS

Low-dose atropine, antimyopia spectacles, antimyopia multifocal soft contact lenses and orthokeratology met our AMM inclusion criteria. Lifetime cost for TMM with 3% discounting was US$7437 (CI US$4953 to US$10 740) in Australia and US$8006 (CI US$3026 to US$13 707) in China. The lowest lifetime cost options with 3% discounting were antimyopia spectacles (US$7280, CI US$5246 to US$9888) in Australia and low-dose atropine (US$4453, CI US$2136 to US$9115) in China.

CONCLUSIONS

Financial investment in AMM during childhood may be balanced or exceeded across a lifetime by reduced refractive progression, simpler lenses, and reduced risk of pathology and vision loss. Our methodology can be applied to estimate cost in comparable scenarios.

A multidisciplinary approach to inherited retinal dystrophies from diagnosis to initial care: a narrative review with inputs from clinical practice

BACKGROUND

Non-syndromic inherited retinal dystrophies (IRDs) such as retinitis pigmentosa or Leber congenital amaurosis generally manifest between early childhood and late adolescence, imposing profound long-term impacts as a result of vision impairment or blindness. IRDs are highly heterogeneous, with often overlapping symptoms among different IRDs, and achieving a definite diagnosis is challenging. This narrative review provides a clinical overview of the non-syndromic generalized photoreceptor dystrophies, particularly retinitis pigmentosa and Leber congenital amaurosis. The clinical investigations and genetic testing needed to establish a diagnosis are outlined, and current management approaches are discussed, focusing on the importance of the involvement of an interdisciplinary team from diagnosis and initial care to long-term follow-up and support.

RESULTS

The effective management of IRDs requires a multidisciplinary, and ideally interdisciplinary, team of experts knowledgeable about IRDs, with experienced professionals from fields as diverse as ophthalmology, neuropsychiatry, psychology, neurology, genetics, orthoptics, developmental therapy, typhlology, occupational therapy, otolaryngology, and orientation and mobility specialties. Accurate clinical diagnosis encompasses a range of objective and subjective assessments as a prerequisite for the genetic testing essential in establishing an accurate diagnosis necessary for the effective management of IRDs, particularly in the era of gene therapies. Improvements in genome sequencing techniques, such as next-generation sequencing, have greatly facilitated the complex process of determining IRD-causing gene variants and establishing a molecular diagnosis. Genetic counseling is essential to help the individual and their family understand the condition, the potential risk for offspring, and the implications of a diagnosis on visual prognosis and treatment options. Psychological support for patients and caregivers is important at all stages of diagnosis, care, and rehabilitation and is an essential part of the multidisciplinary approach to managing IRDs. Effective communication throughout is essential, and the patient and caregivers' needs and expectations must be acknowledged and discussed.

CONCLUSION

As IRDs can present at an early age, clinicians need to be aware of the clinical signs suggesting visual impairment and follow up with multidisciplinary support for timely diagnoses to facilitate appropriate therapeutic or rehabilitation intervention to minimize vision loss.

Rehabilitation Methods for Patients with Geographic Atrophy due to Age-Related Macular Degeneration and Effects of Rehabilitation on Quality of Life

Purpose

The purpose of the study is to evaluate the low vision rehabilitation methods and to investigate the effect of visual rehabilitation on quality of life in patients with low vision due to geographic atrophy from age-related macular degeneration (ARMD).

Methods

The better-seeing eye of 78 patients with geographic atrophy due to ARMD were included in the study. Sociodemographic characteristics, ophthalmological examination findings, and preferred low vision aids for near and distant were recorded. Fifty-seven patients who preferred to use a low vision aid device in daily life were considered as a rehabilitation group, whereas 21 patients who did not use any device were considered as a control group. The National Eye Institute Visual Function Questionnaire (NEI-VFQ-25) was applied to all patients at the initial examination and at least 6 months after the initial examination.

Results

In the rehabilitation group, statistically significant increases were found in the overall composite score, and general vision, near and distance activities, social functioning, mental health, role difficulties, and dependency subscale scores of the NEI-VFQ-25 quality of life scale after low vision rehabilitation (p=0.009 for general vision, p < 0.001; for others). In the control group, there was no statistically significant change in any of the subscale scores or the overall score of the scale (p > 0.05). All patients (n = 78) were recommended to use at least one low vision aid for near vision. Hyperocular glasses were recommended for 77 patients (98.72%), magnifiers for 15 patients (19.23%), electro-optical devices for 2 patients (2.56%), and telemicroscope for one patient (1.28%). Furthermore, 17 patients (21.8%) were prescribed more than one low vision aids. However, for distance vision, only 29 patients (37.18%) received a recommendation for a low vision aid.

Conclusions

Low vision patients with ARMD-related geographic atrophy should meet with low vision aids as soon as possible and should be included in low vision rehabilitation programs.

Compliance With the Use of Low-Vision Aids in a Greek Population: An Explorative Study

The aim of this study is to investigate the compliance with low-vision aids (LVAs) among patients with low vision (LV) in a Greek population. An explorative study was conducted in a sample of patients with LV attending our outpatient unit at the School of Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece. Patients' demographics and daily visual demands were recorded, and they were administered with the National Eye Institute Visual Function Questionnaire-25 (VFQ-25) at baseline. Participants were trained in the use of a wide range of LVAs before their prescription. Evaluation of the use of the LVAs was conducted at one year after the baseline using a structured phone survey. A total of 100 LV patients were included, with 68% of them being older than 65 years and 50 being males. The main cause of LV (57.0%) was age-related macular degeneration, and the mean VFQ-25 score at baseline was 49.2 (SD= 17.8). Overall, 75 patients had been prescribed LVAs, with 76.0% of these patients preferring an optical aid. The vast majority (98.7%) of these patients stated using the LVA one year after the baseline, and 62.1% of them reported using the aid often to very often. Significantly, 76% of these patients reported that their quality of life was positively affected by the use of the aid, and 97.3% would recommend the use of LVA to another individual with the same problem. Providing appropriate training before the prescription is of high significance to improve the rate of compliance with the use of LVAs. These results can be used to develop appropriate strategies in this field.

Barriers and facilitators in the referral pathways to low vision services from the perspective of patients and professionals: a qualitative study

BACKGROUND

Underutilization of and lack of access to low vision services (LVS) has been reported internationally. The purpose of this study was to identify barriers and facilitators in LVS referral procedures and service delivery from both the perspective of people with visual impairment and professionals from different eye care providers in the Netherlands.

METHODS

A qualitative study in the Netherlands was conducted. Barriers and facilitators were explored through semi structured interviews with older adults with macular degeneration, diabetic retinopathy and/or glaucoma (n = 14), and healthcare professionals including ophthalmologists and LVS professionals (n = 16). Framework analysis was used for analyzing the interviews with Atlas.ti software.

RESULTS

According to both patients and professionals, facilitators in LVS access and utilization are having motivation, self-advocacy, high participation needs and social support, as well as being negatively impacted by the impairment. Both samples found having good communication skills and informing patients about LVS as a healthcare provider to facilitate access. A long patient-provider relationship and the Dutch healthcare system were also mentioned as facilitators. Professionals additionally found long disease duration and the presence of low vision optometric services in the ophthalmic practice to promote access. Barriers that were reported by patients and professionals are lack of motivation, self-advocacy and acceptance of the impairment in patients. In addition, having low participation needs as a patient, lack of information provision by providers and time constraints in the ophthalmic practice were mentioned as barriers. Professionals also reported lack of social support, short disease duration of patients, a short patient-provider relationship and lack of coordination of care in the ophthalmic practice to hinder access.

CONCLUSIONS

Findings suggest that providers' lack of information provision about LVS, especially to patients who are less assertive, hamper referral to LVS. Providers should have attention for patients' LVS needs and actively inform them and their social network about LVS to facilitate access. Educating and training providers about how and when to address LVS may help to reduce barriers in the referral pathways. In addition, referral procedures may benefit from tools that make providers more aware of LVS.

Efficacy and Patients' Satisfaction with the ORCAM MyEye Device Among Visually Impaired People: A Multicenter Study

To evaluate usability of and satisfaction with OrCam MyEye, a finger-size wearable assistive technology device for visually impaired during real-world tasks. This prospective multicenter study was conducted on visually impaired people recruited from 5 vision rehabilitation centers. Patients performed real-world tasks such as near and distance reading, money handling, colour identification and face recognition in 2 different scenarios: without using any low vision aid and with OrCam. System Usability Scale (SUS), Patient's Global Impression of Change (PGIC), the Quebec User Evaluation of Satisfaction with Assistive Technology (QUEST 2.0) and the Psychosocial Impact of Assistive Devices Scale (PIADS) were administered after the use of the OrCam device. Among the 100 participants, use of OrCam MyEye device improved many daily-living tasks (F = 1.67, P < .05), and in particular reading and face recognition. Multivariate logistic regression showed that age and visual field defect explained 89% of the variation in efficacy of the device. Nearly half (45%) of the participants indicated a positive rating with the SUS. The PGIC rates showed a minimal improvement with a mean score of 4.2 (SD:1.8). The most highlighted parameter with the QUEST 2.0 test was "ease of use" in 58% (48 subjects). The PIADS indicator showed that the device positively impacted on the daily-living tasks of users (r2 = 0.72, P < .05). Regression modelling demonstrated a good relation between the questionnaires scores and demographic, disease and visual factors (P < .05). OrCam MyEye allowed visually impaired people to read, handle money and face recognition independently. This device may offer to these subjects to be independent.

Telerehabilitation for people with low vision

BACKGROUND

Low vision affects over 300 million people worldwide and can compromise both activities of daily living and quality of life. Rehabilitative training and vision assistive equipment (VAE) may help, but some visually impaired people have limited resources to attend in-person visits to rehabilitation clinics to be trained to learn to use VAE. These people may be able to overcome barriers to care through access to remote, internet-based consultation (telerehabilitation).

OBJECTIVES

To compare the effects of telerehabilitation with face-to-face (e.g. in-office or inpatient) vision rehabilitation services for improving vision-related quality of life and near reading ability in people with visual function loss due to any ocular condition. Secondary objectives were to evaluate compliance with scheduled rehabilitation sessions, abandonment rates for VAE devices, and patient satisfaction ratings.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), which contains the Cochrane Eyes and Vision Trials Register) (2021, Issue 9); Ovid MEDLINE; Embase.com; PubMed; ClinicalTrials.gov; and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP). We did not use any language restriction or study design filter in the electronic searches; however, we restricted the searches from 1980 onwards because the internet was not introduced to the public until 1982. We last searched CENTRAL, MEDLINE Ovid, Embase, and PubMed on 14 September 2021, and the trial registries on 16 March 2022.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) or controlled clinical trials (CCTs) in which participants diagnosed with low vision had received vision rehabilitation services remotely from a human provider using internet, web-based technology compared with an approach involving in-person consultations.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened titles and abstracts retrieved by the searches of the electronic databases and then full-text articles for eligible studies. Two review authors independently abstracted data from the included studies. Any discrepancies were resolved by discussion.

MAIN RESULTS

We identified one RCT/CCT that indirectly met our inclusion criteria, and two ongoing trials that met our inclusion criteria. The included trial had an overall high risk of bias. We did not conduct a quantitative analysis since multiple controlled trials were not identified.  The single included trial of 57 participants utilized a parallel-group design. It compared 30 hours of either personalized low vision training through telerehabilitation with a low vision therapist (the experimental group) with the self-training standard provided by eSight using the eSkills User Guide that was self-administered by the participants at home for one hour per day for 30 days (the comparison group). The trial investigators found a similar direction of effects for both groups for vision-related quality of life and satisfaction at two weeks, three months, and six months. A greater proportion of participants in the comparison group had abandoned or discontinued use of the eSight Eyewear at two weeks than those in the telerehabilitation group, but discontinuance rates were similar between groups at one month and three months. We rated the certainty of the evidence for all outcomes as very low due to high risk of bias in randomization processes and missing outcome data and imprecision.   AUTHORS' CONCLUSIONS: The included trial found similar efficacy between telerehabilitation with a therapist and an active control intervention of self-guided training in mostly younger to middle-aged adults with low vision who received a new wearable electronic aid. Given the disease burden and the growing interest in telemedicine, the two ongoing studies, when completed, may provide further evidence of the potential for telerehabilitation as a platform for providing services to people with low vision.

Posturographic Analysis in Patients Affected by Central and Peripheral Visual Impairment

Although vision loss is known to affect equilibrium maintenance, postural control in patients affected by low vision has been poorly investigated. We evaluated postural stability and the ability to use visual, proprioceptive and vestibular information in different low vision patterns. Ten adults with normal vision (NC), fourteen adults affected by central visual impairment (CLV) and eight adults affected by peripheral visual impairment (PLV) were enrolled in our study. Patients underwent visual, vestibular and postural evaluation (bedside examination, Computed Dynamic Posturograophy). Motor Control Tests were performed to analyze automatic postural adaptive responses elicited by unexpected postural disturbances. Clinical evaluations did not show abnormality in all patients. In the Sensory Organization Test, CLV and PLV patients performed more poorly in conditions 3-6 and 3-4, as compared to NC subjects. The condition 5 score was significantly lower in the CLV group with respect to the PLV patients. Composite equilibrium scores demonstrated significant differences between low-vision subjects vs. NC subjects. No differences were found for somatosensorial contribution. Visual afferences showed lower values in all visually impaired subjects, while vestibular contribution was lower in the CLV patients as compared to the NC and PLV patients. MCT latencies were significantly worse in the CLV subjects. In the low-vision patients, postural control was modified with a specific pattern of strategy adaptation. Different modulations of postural control and different adaptive responses seemed to characterize CLV patients as compared to PLV subjects.

Assessing Higher-Order Visual Processing in Cerebral Visual Impairment Using Naturalistic Virtual-Reality-Based Visual Search Tasks

Cerebral visual impairment (CVI) is a brain-based disorder associated with the maldevelopment of central visual pathways. Individuals with CVI often report difficulties with daily visual search tasks such as finding a favorite toy or familiar person in cluttered and crowded scenes. We developed two novel virtual reality (VR)-based visual search tasks combined with eye tracking to objectively assess higher order processing abilities in CVI. The first (virtual toybox) simulates a static object search, while the second (virtual hallway) represents a dynamic human search task. Participants were instructed to search for a preselected target while task demand was manipulated with respect to the presence of surrounding distractors. We found that CVI participants (when compared to age-matched controls) showed an overall impairment with visual search on both tasks and with respect to all gaze metrics. Furthermore, CVI participants showed a trend of worsening performance with increasing task demand. Finally, search performance was also impaired in CVI participants with normal/near normal visual acuity, suggesting that reduced stimulus visibility alone does not account for these observations. This novel approach may have important clinical utility in helping to assess environmental factors related to functional visual processing difficulties observed in CVI.

Characteristics of Visual Impairment and the Impact of Low Vision Assessment in a Tertiary Academic Hospital in Jordan

Purpose

This project aims to describe the characteristics of patients with visual impairment referred from a tertiary academic hospital in Jordan for a comprehensive low vision evaluation and to study its impact on their functional needs.

Methods

A retrospective analysis of the records of 108 patients from the ophthalmology clinic at Jordan University Hospital over the period from January 2014 to December 2018 was performed. Gathered information included age, gender, clinical diagnosis, family history of ocular disease, and type of low vision aid prescribed and its impact on patients' functional needs.

Results

The mean age was 44.64 years (range 4-88). Most participants were in the 19-60 years age group (50.0%). Fifty percent of the participants were the offspring of consanguineous marriages. The main cause of visual impairment in this cohort was retinitis pigmentosa, followed by diabetic retinopathy. The majority of low vision aids were prescribed for near distance tasks, and reading spectacles were the most prescribed visual aid. Eighty-nine percent of patients reported functional improvement and retained their visual aids upon follow-up.

Conclusion

Retinitis pigmentosa was the main cause of visual impairment in this cohort of patients referred from a tertiary academic hospital for low vision assessment. We report a consanguinity rate of 50%. The overwhelming majority of patients reported functional improvement and retained their visual aids upon follow-up. Awareness and integration of low vision services into a multidisciplinary approach and improving referral protocols is essential to better address the needs of patients with visual impairment. Familial counselling regarding consanguineous marriages and emerging research to treat inherited retinal diseases should be pursued.

Short-Term Clinical Results of Preferred Retinal Locus Training

Objectives

This study evaluated acoustic biofeedback training using microperimetry in patients with foveal scars and an eligible retinal locus for better fixation.

Materials and Methods

A total of 29 eligible patients were enrolled in the study. The acoustic biofeedback training module in the MAIA (Macular Integrity Assessment, CenterVue®, Italy) microperimeter was used for training. To determine the treatment efficacy, the following variables were compared before and after testing: best corrected visual acuity (BCVA); MAIA microperimeter full threshold 4-2 test parameters of average threshold value, fixation parameters P1 and P2, and bivariate contour ellipse area (BCEA) for 63% and 95% of fixation points; contrast sensitivity (CSV 1000E Contrast Sensitivity Test); reading speed using the Minnesota Low-Vision Reading Test (MNREAD reading chart); and quality of life (NEI-VFQ-25). In addition, fixation stability parameters were recorded during each session.

Results

The study group consisted of 29 patients with a mean age of 68.72±8.34 years. Median BCVA was initially 0.8 (0.2-1.6) logMAR and was 0.8 (0.1-1.6) logMAR after 8 weeks of preferred retinal locus training (p=0.003). The fixation stability parameter P1 improved from a mean of 21.28±3.08% to 32.69±3.69% (p=0.001) while mean P2 improved from 52.79±4.53% to 68.31±3.89% (p=0.001). Mean BCEA 63% decreased from 16.11±2.27^°2 to 13.34±2.26^°2 (p=0.127) and mean BCEA 95% decreased from 45.87±6.72^°2 to 40.01±6.78^°2 (p=0.247) after training. Binocular reading speed was 38.28±6.25 words per minute (wpm) before training and 45.34±7.35 wpm after training (p<0.001). Statistically significant improvement was observed in contrast sensitivity and quality of life questionnaire scores after training.

Conclusion

Beginning with the fifth session, biofeedback training for a new trained retinal locus improved average sensitivity, fixation stability, reading speed, contrast sensitivity, and quality of life in patients with macular scarring.

Change in rehabilitation needs and activity limitations over time of adults with acquired visual impairment following entry to a low vision rehabilitation service in England

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, η_p ²  = 0.29), driven by reduced perceived difficulty (p < 0.001, η_p ²  = 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.

Long term outcomes in dry age-related macular degeneration following low vision rehabilitation interventions

Background:

Age-related macular degeneration (AMD) is the leading cause of loss of vision in the older age groups. In the absence of a known therapy, low vision rehabilitation aims at preserving residual functional vision at optimal levels. Long term functional outcomes from Low Vision Rehabilitation (LVR) in AMD cases were never scrutinized in the past. This study brings some clarification in this matter.

Methods:

This is a retrospective case series study including data up to 2 years following the baseline visit. Low Vision Assessments included microperimetry testing and recommendations for low vision devices for distance vision. Outcomes measures selected for this study were best corrected distance visual acuity, fixation stability and preferred retinal locus (PRL) topography and LVR interventions.

Results:

Data on 17 patients with an average age of 89.2 ± 4.4 years was collected. In those with better vision than 20/400 loss of vision was about 1.4 letter per year as tested with ETDRS charts compared with losses of four letters per year in a population without LVR interventions. Fixation stability continued to deteriorate while PRL eccentricity seemed to remain the same. In about half of cases there was a change in the topographic location of the PRL to a different retinal quadrant.

Conclusion:

Long term, as expected, changes were noticed in visual acuity, fixation stability and PRL topography. However, it seems that LVR interventions for distance vision help patients retain significantly better functional vision at the 2 years follow up interval when compared to others.

Impact of Lighting Assessment and Optimization on Participation and Quality of Life in Individuals with Vision Loss

This pilot study was designed to investigate the effects of a holistic lighting intervention on the quality of life for individuals with low vision. Sixty participants (44 women; median age 69 years) with visual impairment received lighting interventions, including a home visit and consultation in a lighting lab. Assisted by low vision consultants, participants evaluated their performance using the Canadian Occupational Performance Measure (COPM) before and after the intervention. Improvements in visual functioning and quality of life were evaluated using the 39-item National Eye Institute Visual Function Questionnaire (NEI VFQ-39), the Groffman Visual Tracing Test, and the Farnsworth Dichotomous Test (D15). Following the lighting intervention, scores improved for all activities in the COPM (p < 0.01), for near activities and vision-specific role difficulties in the VFQ-39 (p < 0.05), and overall in the D15 test (p < 0.05). These results suggest the intervention provided an effective method for improving the participants' quality of life and performance.

Perspective on Vision Science-Informed Interventions for Central Vision Loss

Pathologies affecting central vision, and macular degeneration (MD) in particular, represent a growing health concern worldwide, and the leading cause of blindness in the Western World. To cope with the loss of central vision, MD patients often develop compensatory strategies, such as the adoption of a Preferred Retinal Locus (PRL), which they use as a substitute fovea. However, visual acuity and fixation stability in the visual periphery are poorer, leaving many MD patients struggling with tasks such as reading and recognizing faces. Current non-invasive rehabilitative interventions are usually of two types: oculomotor, aiming at training eye movements or teaching patients to use or develop a PRL, or perceptual, with the goal of improving visual abilities in the PRL. These training protocols are usually tested over a series of outcome assessments mainly measuring low-level visual abilities (visual acuity, contrast sensitivity) and reading. However, extant approaches lead to mixed success, and in general have exhibited large individual differences. Recent breakthroughs in vision science have shown that loss of central vision affects not only low-level visual abilities and oculomotor mechanisms, but also higher-level attentional and cognitive processes. We suggest that effective interventions for rehabilitation after central vision loss should then not only integrate low-level vision and oculomotor training, but also take into account higher level attentional and cognitive mechanisms.

Barriers to Low Vision Services Among Optometrists in Saudi Arabia

Introduction:

This study identifies the barriers and challenges to the provision of low vision services among practicing optometrists in Saudi Arabia.

Methods:

In this study, a self-administered online structured survey for practicing optometrists was used. Responses were collected to understand the number and percentage of low vision service providers, level of awareness, and barriers to the provision of low vision services.

Results:

This study included 154 (79 females and 75 males) practicing optometrists. They were from the five regions of Saudi Arabia (23 cities). The age of the practitioners ranged from 22 to 54 years. They had Bachelor’s, Master’s, and Doctor of Philosophy degrees. Forty-four participants (30%) provided low vision services. The major barriers reported were lack of training (87%), lack of awareness about low vision services (76%), lack of availability of low vision devices (70%), lack of motivation (65%), low vision services being time-consuming (55%), being busy in providing general optometry (65%), and lack of financial sources (31%).

Conclusion:

Building an efficient model for low vision rehabilitation in Saudi Arabia is needed. Moreover, encouraging more optometrists to be involved in low vision rehabilitation is necessary. There is also a need for more low vision education, national health coverage of patients with low vision, and better collaboration between low vision service providers.

Evaluation of vision-related quality of life in retinitis pigmentosa patients with low vision

PURPOSE

To investigate the effect of sociodemographic and clinical characteristics on vision-related quality of life (QoL) in retinitis pigmentosa (RP) patients with low vision.

STUDY DESIGN

Retrospective.

PATIENTS AND METHODS

Thirty-three RP patients with low vision who had tunnel vision due to RP and 27 volunteers with healthy vision (controls) were included in the study. Visual loss was classified according to the International Classification of Diseases (ICD-10). The National Eye Institute Visual Function Questionnaire-25 (NEI VFQ-25) was used to determine vision-related QoL. Static automated perimetry (Central 30-2 threshold program) was used for visual field testing, and the degree of the central visual field was calculated. Reading speed was calculated using the Minnesota Low-Vision Reading Acuity Chart (MNREAD) with best near correction.

RESULTS

The mean total scores from the NEI VFQ-25 were 47.8 ± 15.8 in the RP group and 94.8 ± 4.3 in the control group (P < .001 for total and subscale scores). The mean total score and the social functioning and dependency scores were higher in the men than in the women (P = .016). The NEI VFQ-25 scores increased when reading speed was above 80 words per minute (wpm). Positive correlations were found between the degree of the central visual field and the mean total score and the general vision, near, and distance activities; social functioning; mental health; role difficulties; dependency; and color vision scores. The factors that affected the NEI-VFQ-25 score the most were male sex and degree of the central visual field in the RP group, whilst education level and the presence of systemic disease were the most effective factors in the controls.

CONCLUSION

The only modifiable factor affecting vision-related QoL in patients with RP was reading speed; thus, QoL could improve if reading speed is increased in patients with RP.

Restitution of potential visual acuity in low vision patients with the use of yoke prisms

PURPOSE

To determine the efficacy of prisms when used for redirection of incoming images towards the preferred reinal loci (PRLs) for restitution of potential visual acuity (PVA) in low vision cases with age-related macular degeneration (AMD).

METHODS

Retrospective comparative interventional case series review. Low vision rehabilitation (LVR) protocol used included best corrected visual acuity (BCVA), PVA, topographic PRL identification and use of prisms to produce image redirection to the presumed PRL. The primary outcome measure selected for analysis was BCVA for viewing distance targets after use of yoke prisms.

RESULTS

Image relocation with prisms in patients with AMD resulted in significantly better BCVA levels (t₃₂ = 8.57, p < 0.0001) in the better eye. Distance BCVA levels achieved were almost identical to PVA levels (t₃₂ = 0.415, p < 0.681) (y= -0.136 + 1.195x, r = 0.8333, p < 0.001).

CONCLUSIONS

Use of yoke prisms for image redirection towards a peripheral identifiable PRL may result in PVA restitution in most cases.

Case Report: Visual Rehabilitation in Hemianopia Patients. Home-Based Visual Rehabilitation in Patients With Hemianopia Consecutive to Brain Tumor Treatment: Feasibility and Potential Effectiveness

Background/Objectives: Visual field loss is frequent in patients with brain tumors, worsening their daily life and exacerbating the burden of disease, and no supportive care strategies exist. In this case series, we sought to characterize the feasibility and potential effectiveness of a home-based visual rehabilitation program in hemianopia patients using immersive virtual-reality stimulation. Subjects/Methods: Two patients, one with homonymous hemianopia and the other with bitemporal hemianopia, consecutive to pediatric brain tumors, with no prior visual rehabilitation performed 15 min of home-based audiovisual stimulation every 2 days for 6 weeks (case 2) and 7 weeks (case 1) between February and August 2020. Patients used a virtual-reality, stand-alone, and remotely controlled device loaded with a non-commercial audiovisual stimulation program managed in real time from the laboratory. Standard visual outcomes assessed in usual care in visual rehabilitation were measured at the clinic. Following a mixed method approach in this pragmatic study of two cases, we collected quantitative and qualitative data on feasibility and potential effectiveness and compared the results pre- and post-treatment. Results: Implementation and wireless delivery of the audiovisual stimulation, remote data collection, and analysis for cases 1 and 2 who completed 19/20 and 20/20 audiovisual stimulation sessions at home, respectively, altogether indicated feasibility. Contrast sensitivity increased in both eyes for cases 1 and 2. Visual fields, measured by binocular Esterman and monocular Humphrey full-field analyses, improved in case 1. A minor increase was observed in case 2. Cases 1 and 2 enhanced reading speed. Case 2 strongly improved quality of life scores. Conclusion: This is the first report of a home-based virtual-reality visual rehabilitation program for adult patients with hemianopia consecutive to a pediatric brain tumor. We show the feasibility in real-world conditions and potential effectiveness of such technology on visual perception and quality of life.

Role of improved distance and near visual acuity with low vision aids to enhance stereopsis in retinal diseases

Purpose:

The purpose of this study was to examine role of improved distance and near best-corrected visual acuity (DBCVA and NBCVA) with use of magnification devices to enhance stereopsis in low vision (LV) subjects having retinal diseases.

Methods:

In a cross-sectional observational study without control, 84 subjects having LV due to retinal diseases were examined for an improvement of BCVA with use of magnifying low vision aids (LVAs) (2X for DBCVA and 3X for NBCVA). The stereopsis scores on titmus fly test were recorded with near refractive correction “on” and then with 3X magnification. The improvement in stereopsis for distance was however estimated through statistical correlation values.

Results:

The DBCVA (P < 0.001), NBCVA (P < 0.001) and stereopsis (P < 0.001) improved statistically significantly (SS) following magnifying LVA. There was no correlation between pre-LVA stereopsis and pre-LVA DBCVA (r = 0.059; P = 0.444;NSS) and post-LVA DBCVA (r = 0.054; P = 0.487;NSS); and no correlation between post-LVA stereopsis and pre-LVA DBCVA (r = 0.042; P = 0.592;NSS) and post-LVA DBCVA (r = 0.08; P = 0.920;NSS). There was no correlation between pre-LVA stereopsis and pre-LVA NBCVA (r = 0.044; P = 0.572;NSS) and no correlation between post-LVA stereopsis and pre-LVA NBCVA (r = 0.108; P = 0.165;NSS). But positive correlation between pre-LVA stereopsis and post-LVA NBCVA (r = 0.347; P < 0.001) and between post-LVA stereopsis and post-LVA NBCVA (r = 0.445; P < 0.001) was SS.

Conclusion:

The use of magnification as LVA improves both the BCVA and stereopsis. The increase in DBCVA with LVA improves the stereopsis for distance though it may not be SS while improvement in NBCVA with LVA enhances stereopsis for near objects in SS manner.

An Audiovisual 3D-Immersive Stimulation Program in Hemianopia Using a Connected Device

BACKGROUND Homonymous hemianopia is a loss of conscious vision in one hemifield, strongly affecting everyday life. Audiovisual stimulation programs improve visual perception in the blind hemifield; however, they use large equipment operated in clinical settings. Such treatments require frequent visits at the clinic, hampering the patient's adherence and compliance. In one hemianopia patient, we tested a 4-week dynamic audiovisual rehabilitation program in the stand-alone, remotely controlled, virtual-reality, head-mounted display Oculus Go and measured the effect on visual perception. CASE REPORT A 15-year-old Caucasian male was diagnosed with a right homonymous hemianopia with splitting of central fixation after a traumatic occipital contusion at age 7 months. Visual assessment showed impaired binocular contrast sensitivity and retinal sensitivity. Fixation stability and visual fields were strongly affected. After a 4-week audiovisual rehabilitation program, including 3 hours 20 minutes of stimulation, the contrast sensitivity, fixation stability, and paracentral visual perception were significantly enhanced, improving quality of life. CONCLUSIONS This pioneering work reports the use of virtual-reality in a head-mounted display to provide an audiovisual stimulation protocol for low-vision rehabilitation in a hemianopia patient. Real-time data recording and remote control of the stimulation program demonstrate that such rehabilitation treatment can be performed by the patient at home without interruption of care, decreasing the burden of disease. Beneficial effects on visual function were measured according to clinical guidelines of low-vision assessment. Improvement in visual function and quality of life challenge the prevailing belief that post-acute vision loss is both permanent and unchangeable.

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

SIGNIFICANCE

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Everyday visual demands of people with low vision: A mixed methods real-life recording study

Research has demonstrated that low vison aids (LVAs) can have a positive impact on the functional sight of those living with sight loss. Step changes in technology are now enabling new wearable LVAs with greater potential than those available previously. For these novel devices to receive increased acceptance and therefore adoption by those with sight loss, visual task demands have to be understood more clearly in order to enable better alignment between device design and user requirements. The aim of this study was to quantify these requirements. Thirty-two participants aged 18 to 87 wore a spectacle-mounted video camera to capture and narrate all everyday situations in which they would use a “perfect” sight aid during 1 week. Captured scenes were analyzed through categorization and computational image analysis. Results showed large variation in activities and lifestyles. Participants reported no available sight aid or coping strategy for 57% of the recorded activities. Reading made up 49% of all recorded tasks, the other half comprising non-textual information. Overall, 75% of captured activities were performed ad hoc (duration of 0–5 minutes), 78% occurred indoors, 58% occurred at home, 48% were lit by natural light, 68% included the object of interest within reach, and 69% required a single focus plane only. Around half of captured objects of interest had a size of 2 degrees visual angle (2.08 logarithm of the minimum angle of resolution [logMAR]) or smaller. This study highlights the need for a sight aid that can make both textual and non-textual scenes accessible while offering flexibility to accommodate individual lifestyles.

A Novel Radiologic Finding to Predict Ophthalmic Abnormalities in Children With Congenital Zika Syndrome

BACKGROUND

The Zika virus (ZIKV) epidemic had devastating consequences in Brazil. We investigated whether a radiologic finding (ie, infratentorial abnormalities) was associated with sight-threatening defects in children born with congenital Zika syndrome (CZS). We also investigated whether ophthalmic abnormalities correlated with head circumference (HC) and gestational age of infection.

METHODS

Cross-sectional evaluation based upon a previous cohort from March 2016 to December 2018, in Paraíba, Brazil. The study population was comprised of children born to mothers with laboratory-confirmed ZIKV infection during pregnancy (ZIKV reverse transcriptase polymerase chain reaction [RT-PCR]+) and children born with clinical and radiologic features of CZS.

RESULTS

A total of 75 infants had complete data. All 75 had brain calcifications. Microcephaly was present in 53 (71%) of them. Infratentorial abnormalities were present in 17 infants (22.7%). Ophthalmic abnormalities were seen in 16 of the 17 children (94%) with infratentorial abnormalities, while 28% of children without infratentorial abnormalities had ophthalmic findings (odds ratio [OR]: 42.0; 95% confidence interval [CI]: 5.1-342.9). Similar associations were observed when macular chorioretinal atrophy and optic nerve abnormalities were analyzed individually (OR: 23.7; 95% CI: 6.0-93.3 and OR: 11.5; 95% CI: 3.3-40.0, respectively). Infratentorial abnormalities were more frequently associated with ophthalmic abnormalities (94%) than microcephaly (43.4%) (P < .001). Mean HC was statistically different between groups with and without ophthalmic abnormalities (P = .01). A statistically significant difference in gestational age between both groups was not noted (P = .12).

CONCLUSIONS

In children with CZS, the presence of infratentorial abnormalities is a significant predictor of ophthalmic abnormalities. All neonates whose mothers had ZIKV exposure during pregnancy should have an ophthalmologic examination.

Topical Review: Assessment of Binocular Sensory Processes in Low Vision

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.

Visuoperceptive Impairments in Severe Alcohol Use Disorder: A Critical Review of Behavioral Studies

The present literature review is aimed at offering a comprehensive and critical view of behavioral data collected during the past seventy years concerning visuoperception in severe alcohol use disorders (AUD). To pave the way for a renewal of research and clinical approaches in this very little understood field, this paper (1) provides a critical review of previous behavioral studies exploring visuoperceptive processing in severe AUD, (2) identifies the alcohol-related parameters and demographic factors that influence the deficits, and (3) addresses the limitations of this literature and their implications for current clinical strategies. By doing so, this review highlights the presence of visuoperceptive deficits but also shows how the lack of in-depth studies exploring the visual system in this clinical population results in the current absence of integration of these deficits in the dominant models of vision. Given the predominance of vision in everyday life, we stress the need to better delineate the extent, the specificity, and the actual implications of the deficits for severe AUD.

Post audio-visual biofeedback training visual functions and quality of life in paediatric idiopathic infantile nystagmus: A pilot study

Purpose:

Biofeedback training (BT) was adapted to idiopathic infantile nystagmus syndrome (IINS) cases to enhance visual functions and quality of life (QoL).

Methods:

10 patients (age 9 ± 3.2 years) treated with the audio-visual BT module of the MAIA microperimeter (Centervue, Padova, Italy) were assessed in two baseline visits and 1week post-BT (BT 80 min in total). The outcomes were distance and near binocular best corrected visual acuity (BBCVA), fixation stability, reading speed, contrast sensitivity, stereopsis and Children’s Visual Function Questionnaire. One-way repeated measured ANOVA and paired t-tests were used.

Results:

Distance BBCVA improved from 0.46 ± 0.21 and 0.43 ± 0.18 pre-BT to 0.33 ± 0.2 logMAR post-BT (F (2,27) = 13.75, p = 0.0002). Post-BT was better than baseline (p = 0.0001) and pre-BT (p = 0.001). Near BBCVA improved from 0.23 ± 0.09 and 0.21 ± 0.14 pre-BT to 0.04 ± 0.08 post-BT (F (2,27) = 22.12, p = 0.000014), post-BT was better than baseline (p = 0.0001) and pre-BT (p = 0.0006). Stereopsis improved from 283 ± 338″ to 39 ± 32.2″ (p = 0.04), contrast sensitivity from 0.26 ± 0.17 to 0.08 ± 0.12 log units (p = 0.01), and reading speed improved from 74.7 ± 51.2 wpm to 104.7 ± 53.6 wpm (p = 0.0006). Fixation stability improved from 33.6 ± 28.1 to 14.3 ± 10.1 sq. QoL increased from 23.8 ± 2.2 to 26.3 ± 2.3 units (p = 0.001).

Conclusion:

BT benefited all visual functions and QoL in this pilot study, heralding a new possibility for Low Vision Rehabilitation in IINS.

Differential Circuit Mechanisms of Young and Aged Visual Cortex in the Mammalian Brain

The main goal of this review is to summarize and discuss (1) age-dependent structural reorganization of mammalian visual cortical circuits underlying complex visual behavior functions in primary visual cortex (V1) and multiple extrastriate visual areas, and (2) current evidence supporting the notion of compensatory mechanisms in aged visual circuits as well as the use of rehabilitative therapy for the recovery of neural plasticity in normal and diseased aging visual circuit mechanisms in different species. It is well known that aging significantly modulates both the structural and physiological properties of visual cortical neurons in V1 and other visual cortical areas in various species. Compensatory aged neural mechanisms correlate with the complexity of visual functions; however, they do not always result in major circuit alterations resulting in age-dependent decline in performance of a visual task or neurodegenerative disorders. Computational load and neural processing gradually increase with age, and the complexity of compensatory mechanisms correlates with the intricacy of higher form visual perceptions that are more evident in higher-order visual areas. It is particularly interesting to note that the visual perceptual processing of certain visual behavior functions does not change with age. This review aims to comprehensively discuss the effect of normal aging on neuroanatomical alterations that underlie critical visual functions and more importantly to highlight differences between compensatory mechanisms in aged neural circuits and neural processes related to visual disorders. This type of approach will further enhance our understanding of inter-areal and cortico-cortical connectivity of visual circuits in normal aging and identify major circuit alterations that occur in different visual deficits, thus facilitating the design and evaluation of potential rehabilitation therapies as well as the assessment of the extent of their rejuvenation.

Essential components of rehabilitation services provided to visually impaired people

CLINICAL RELEVANCE

This study was conducted to determine the essential components in the delivery of vision rehabilitation services. The findings could be useful in the planning of vision rehabilitation services by optometrists or health managers.

BACKGROUND

Appropriate models of delivering vision rehabilitation services are a challenge for service providers worldwide. Studies have not revealed the key characteristics of a suitable model for delivering vision rehabilitation services. This study investigated the viewpoints of the key informants for identifying the most important components of a suitable model for delivering vision rehabilitation services.

METHODS

Semi-structured in-depth interviews were conducted with 19 participants including managers and service providers in Iran. All the interviews were recorded and transcribed verbatim. An inductive framework analysis approach was used to analyse the data. Qualitative analysis was done using the MAXQDA 10 software.

RESULTS

Four main themes emerged from the data, including creating maximum access (three subcategories: screening for visual impairment, creating a stepped-model for service delivery, and public and professional awareness of vision rehabilitation services), early intervention (two sub-categories: timely identification of people at the onset of disability and starting off with counselling services), need for financial support (two subcategories: providing affordable visual aid equipment and insurance coverage), and informed and skilled personnel (two subcategories: training vision rehabilitation specialists and familiarity of the rehabilitation staff with the rehabilitation program).

CONCLUSION

This study identified the key features of an appropriate model for providing vision rehabilitation services to blind and visually impaired people from the viewpoints of key informants who were experienced in providing vision rehabilitation services. The findings have valuable implications for policy-making and planning for vision rehabilitation services by the health system.

Validation of the visual acuity iPad app Eye Chart Pro compared to the standard Early Treatment Diabetic Retinopathy Study chart in a low-vision population

INTRODUCTION

A low-vision assessment (LVA) is central to developing a vision rehabilitation plan. However, access to LVAs is often limited by the quantity and geographic distribution of low-vision providers, as well as patient-centred transportation challenges. A tablet-based LVA tool kit, delivered virtually, has the potential to overcome many of these barriers. The purpose of this research was to validate a key component of the tablet-based tool kit - a commercially available iPad visual acuity (VA) test (Eye Chart Pro) iPad app - in a low-vision population.

METHODS

Participants with low vision (n = 26) and those who were normally sighted (n = 25) underwent VA testing with both the iPad VA test application and the Early Treatment Diabetic Retinopathy Study (ETDRS) chart. The VA data were compared using a t-test, linear regression and Bland-Altman analysis.

RESULTS

There was no significant difference in the mean absolute difference in VA (log of minimum angle of resolution (logMAR)=0.11; p = 0.82). Eye Chart Pro and Standard ETDRS Chart measures were also not significantly different (p = 0.98). However, there were significant differences between test methods in the low-vision group and the normally sighted group (p > 0.0001 and p = 0.007, respectively). The Bland-Altman analysis showed a mean bias (difference) of -0.0005 logMAR between methods, and 95% limits of agreement of 0.298 and -0.299 logMAR.

DISCUSSION

The ETDRS chart function on the Eye Chart Pro application can reliably measure VA across a range, from normally sighted patients to those with low vision.

Validation of a portable, remotely delivered refraction approach compared to standard in-clinic refraction in a low-vision population

INTRODUCTION

A low-vision assessment (LVA) is critical in developing a vision rehabilitation plan. A remotely delivered LVA that replicates a standard in-clinic assessment may bridge the gap for patients not accessing care due to the limited quantity and distribution of low-vision providers. Within an LVA, an accurate and consistent assessment of refraction error is an essential component. No system has currently been validated for the purposes of a remote LVA. The purpose of this study was to validate a commercially available portable refraction approach in a low-vision population.

METHODS

Low-vision patients (n = 26) or normally sighted patients (n = 25) underwent a refraction assessment using the Adaptica® 2WIN autorefractor, adaptor scope (Kaleidos) and VisionFit phoropter portable refraction devices, as well as a standard autorefractor (Huvitz) and phoropter (Haag-Streit). Refraction data between systems and populations were compared using intraclass correlations. Bland-Altman plots were used to assess the differences between devices.

RESULTS

Spherical equivalent values were found to be reproducible between standard and experimental autorefraction devices (intraclass correlation coefficient (ICC) > 0.8) in both low-vision and normally sighted groups. Similarly, manifest refraction was highly consistent (ICC > 0.8) between devices in all groups. The Bland-Altman plots showed clinically acceptable mean differences of 0.701 between autorefraction methods and -0.116 between manifest refraction methods.

DISCUSSION

The 2WIN/VisionFit system can reliably generate refraction values across a spectrum of errors in normally sighted and visually impaired people, and would be feasible to deliver remotely.

Environmental and behavioural interventions for reducing physical activity limitation and preventing falls in older people with visual impairment

BACKGROUND

Impairment of vision is associated with a decrease in activities of daily living. Avoidance of physical activity in older adults with visual impairment can lead to functional decline and is an important risk factor for falls. The rate of falls and fractures is higher in older people with visual impairment than in age-matched visually normal older people. Possible interventions to reduce activity restriction and prevent falls include environmental and behavioral interventions.

OBJECTIVES

We aimed to assess the effectiveness and safety of environmental and behavioral interventions in reducing physical activity limitation, preventing falls and improving quality of life amongst visually impaired older people.

SEARCH METHODS

We searched CENTRAL (including the Cochrane Eyes and Vision Trials Register) (Issue 2, 2020), Ovid MEDLINE, Embase and eight other databases to 4 February 2020, with no language restrictions.

SELECTION CRITERIA

Eligible studies were randomized controlled trials (RCTs) and quasi-randomized controlled trials (Q-RCTs) that compared environmental interventions, behavioral interventions or both, versus control (usual care or no intervention); or that compared different types of environmental or behavioral interventions. Eligible study populations were older people (aged 60 and over) with irreversible visual impairment, living in their own homes or in residential settings. To be eligible for inclusion, studies must have included a measure of physical activity or falls, the two primary outcomes of interest. Secondary outcomes included fear of falling, and quality of life.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. We assessed the certainty of the evidence using the GRADE approach.

MAIN RESULTS

We included six RCTs (686 participants) conducted in five countries (Australia, Hungary, New Zealand, UK, US) with follow-up periods ranging from two to 12 months. Participants in these trials included older adults (mean age 80 years) and were mostly female (69%), with visual impairments of varying severity and underlying causes. Participants mostly lived in their homes and were physically independent. We classified all trials as having high risk of bias for masking of participants, and three trials as having high or unclear risk of bias for all other domains. The included trials evaluated various intervention strategies (e.g. an exercise program versus home safety modifications). Heterogeneity of study characteristics, including interventions and outcomes, (e.g. different fall measures), precluded any meta-analysis. Two trials compared the home safety modification by occupational therapists versus social/home visits. One trial (28 participants) reported physical activity at six months and showed no evidence of a difference in mean estimates between groups (step counts: mean difference (MD) = 321, 95% confidence interval (CI) -1981 to 2623; average walking time (minutes): MD 1.70, 95% CI -24.03 to 27.43; telephone questionnaire for self-reported physical activity: MD -3.68 scores, 95% CI -20.6 to 13.24; low-certainty of evidence for each outcome). Two trials reported the proportion of participants who fell at six months (risk ratio (RR) 0.76, 95% CI 0.38 to 1.51; 28 participants) and 12 months (RR 0.59, 95% CI 0.43 to 0.80, 196 participants) with low-certainty of evidence for each outcome. One trial (28 participants) reported fear of falling at six months, using the Short Falls Efficacy Scale-International, and found no evidence of a difference in mean estimates between groups (MD 2.55 scores, 95% CI -0.51 to 5.61; low-certainty of evidence). This trial also reported quality of life at six months using 12-Item Short Form Health Survey, and showed no evidence of a difference in mean estimates between groups (MD -3.14 scores, 95% CI -10.86 to 4.58; low-certainty of evidence). Five trials compared a behavioral intervention (exercise) versus usual activity or social/home visits. One trial (59 participants) assessed self-reported physical activity at six months and showed no evidence of a difference between groups (MD 9.10 scores, 95% CI -13.85 to 32.5; low-certainty of evidence). Three trials investigated different fall measures at six or 12 months, and found no evidence of a difference in effect estimates (RRs for proportion of fallers ranged from 0.54 (95% CI 0.29 to 1.01; 41 participants); to 0.93 (95% CI 0.61 to 1.39; 120 participants); low-certainty of evidence for each outcome). Three trials assessed the fear of falling using Short Falls Efficacy Scale-International or the Illinois Fear of Falling Measure from two to 12 months, and found no evidence of a difference in mean estimates between groups (the estimates ranged from -0.88 score (95% CI -2.72 to 0.96, 114 participants) to 1.00 score (95% CI -0.13 to 2.13; 59 participants); low-certainty of evidence). One trial (59 participants) assessed the European Quality of Life scale at six months (MD -0.15 score, 95% CI -0.29 to -0.01), and found no evidence of a clinical difference between groups (low-certainty of evidence).

AUTHORS' CONCLUSIONS

There is no evidence of effect for most of the environmental or behavioral interventions studied for reducing physical activity limitation and preventing falls in visually impaired older people. The certainty of evidence is generally low due to poor methodological quality and heterogeneous outcome measurements. Researchers should form a consensus to adopt standard ways of measuring physical activity and falls reliably in older people with visual impairments. Fall prevention trials should plan to use objectively measured or self-reported physical activity as outcome measures of reduced activity limitation. Future research should evaluate the acceptability and applicability of interventions, and use validated questionnaires to assess the adherence to rehabilitative strategies and performance during activities of daily living.

Telerehabilitation for people with low vision

BACKGROUND

Low vision affects over 300 million people worldwide and can compromise both activities of daily living and quality of life. Rehabilitative training and vision assistive equipment (VAE) may help, but some visually impaired people have limited resources to attend in-person visits at rehabilitation clinics to receive training to learn to use VAE. These people may be able to overcome barriers to care through remote, Internet-based consultation (i.e. telerehabilitation).

OBJECTIVES

To compare the effects of telerehabilitation with face-to-face (e.g. in-office or inpatient) vision rehabilitation services for improving vision-related quality of life and near reading ability in people with visual function loss due to any ocular condition. Secondary objectives were to evaluate compliance with scheduled rehabilitation sessions, abandonment rates for VAE devices, and patient satisfaction ratings.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register) (2019, Issue 6); Ovid MEDLINE; Embase.com; PubMed; ClinicalTrials.gov, and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP). We did not use any language restriction or study design filter in the electronic searches; however, we restricted the searches from 1980 onwards because the Internet was not introduced to the public until 1982. We last searched the electronic databases on 24 June 2019.

SELECTION CRITERIA

We planned to include randomized controlled trials (RCTs) or controlled clinical trials (CCTs) in which participants diagnosed with low vision were undergoing low vision rehabilitation using an Internet, web-based technology compared with an approach involving in-person consultations.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened titles and abstracts and then full-text articles against the eligibility criteria. We planned to have two review authors independently abstract data from the included studies. Any discrepancies were resolved by discussion.

MAIN RESULTS

We identified two ongoing studies, but did not find any completed RCTs and CCTs that met the inclusion criteria for this review. We did not conduct a quantitative analysis. We discussed review articles on telemedicine for facilitating communication with elderly individuals or for providing remote ophthalmological care.

AUTHORS' CONCLUSIONS

We did not find any evidence from RCTs or CCTs on the efficacy of using telerehabilitation for remote delivery of rehabilitation services to individuals with low vision. Given the disease burden and the growing interest in telemedicine, the two ongoing studies, when completed, may provide evidence in understanding the potential for telerehabilitation as a platform for providing services to people with low vision.

Cost-effectiveness of basic vision rehabilitation (The basic VRS-effect study): study protocol for a randomised controlled trial

PURPOSE

To investigate the cost-effectiveness of a basic vision rehabilitation service (basic-VRS) in Portugal. We designed a parallel group, randomised controlled trial whose aim is to compare the effects and costs of 'usual low vision care' with a 'basic-VRS intervention' on self-reported visual ability and other psychosocial and health-related quality-of-life outcomes.

METHODS

The trial will recruit participants that meet the following inclusion criteria: (1) visual acuity between 0.4-1.0 logMAR in the better-seeing eye, (2) cause of vision loss is diabetic retinopathy or age-related macular degeneration, (3) 18 years or older and iv) live in the community (not in nursing homes or other type of institution). Participants will be randomised to one of the study arms consisting of immediate intervention and delayed intervention. The delayed intervention group will receive 'usual care' or no intervention in the first 12 weeks. Visual acuity, contrast sensitivity and retinal structure will be assessed during the study.

RESULTS

The primary outcome measure is visual ability, which will be evaluated with the Massof Activity Inventory, we expect that the intervention will raise the overall person measure or visual ability. Reading, health-related quality-of-life, anxiety and depression and social support will be also assessed. The analysis will be undertaken on an intention-to-treat basis. A cost-effectiveness analysis will be performed to provide information about the cost per unit of utility. To evaluate the cost-effectiveness of the intervention we will adopt the perspective of the healthcare system.

CONCLUSION

This study will provide additional evidence about the effects of basic-VRS on self-reported visual ability. Findings from this study should also contribute to better planning of low vision provision and, consequently, may contribute to reduce barriers to basic-VRS.

A novel Bayesian adaptive method for mapping the visual field

Measuring visual functions such as light and contrast sensitivity, visual acuity, reading speed, and crowding across retinal locations provides visual-field maps (VFMs) that are extremely valuable for detecting and managing eye diseases. Although mapping light sensitivity is a standard glaucoma test, the measurement is often noisy (Keltner et al., 2000). Mapping other visual functions is even more challenging. To improve the precision of light-sensitivity mapping and enable other VFM assessments, we developed a novel hybrid Bayesian adaptive testing framework, the qVFM method. The method combines a global module for preliminary assessment of the VFM's shape and a local module for assessing individual visual-field locations. This study validates the qVFM method in measuring light sensitivity across the visual field. In both simulation and psychophysics studies, we sampled 100 visual-field locations (60° × 60°) and compared the performance of qVFM with the qYN procedure (Lesmes et al., 2015) that measured light sensitivity at each location independently. In the simulations, a simulated observer was tested monocularly for 1,000 runs with 1,200 trials/run, to compare the accuracy and precision of the two methods. In the experiments, data were collected from 12 eyes (six left, six right) of six human subjects. Subjects were cued to report the presence or absence of a target stimulus, with the luminance and location of the target adaptively selected in each trial. Both simulations and a psychological experiment showed that the qVFM method can provide accurate, precise, and efficient mapping of light sensitivity. This method can be extended to map other visual functions, with potential clinical signals for monitoring vision loss, evaluating therapeutic interventions, and developing effective rehabilitation for low vision.

Biofeedback fixation training method for improving eccentric vision in patients with loss of foveal function secondary to different maculopathies

Purpose

Fixation stability (FS) of the preferred retinal locus (PRL) may be improved by biofeedback fixation training (BFT) with microperimetry. Such training can be done on the patient’s PRL or in different retinal loci with better functional characteristics. We studied both options and compared the outcomes.

Methods

Sixty-seven consecutive patients with bilateral central vision loss, poor FS and visual acuity (VA) lower than 0.3 LogMAR were recruited for BFT with microperimeter. Patients were assigned into 2 groups. In group A, BFT was performed on the patient’s spontaneous PRL. In group B, PRL was located between 2 adjacent loci with the highest light sensitivity and the lowest distance from the fovea. Two sets of 12 weekly BFT sessions were performed. Primary outcomes were: FS, VA and reading speed.

Results

Outcomes were statistically significantly better in group B. Mean percentage of FS at therapy end improved from 32 to 35% for group A and from 40 to 55% in group B. Mean VA improved from 1 to 0.86 in group A and from 1 to 0.84 in group B. Reading speed (wpm) improved from 56 to 58 in group A and from 63 to 89 in group B.

Conclusions

This study describes a reliable methodology of improving eccentric fixation stability using BFT in microperimetry, when the fixation training locus is individualized as the retinal area with best functional characteristics. Further studies are needed to validate its value in a larger scale of patients, at different stages of the disease, and its persistence over time.

Rehabilitation with biofeedback training in age-related macular degeneration for improving distance vision

OBJECTIVES

Biofeedback training (BT) is a modern method for enhancing the use of preferred retinal loci (PRL) retraining for new retinal loci (TRL), hence improving far and near vision. This article attempts to clarify the optimal methodology for BT and the types of patients who can benefit most from BT.

METHODS

This is a retrospective review of cases who received BT with the macular integrity assessment (MAIA) microperimetre. Outcome measures selected for analysis were visual acuity, PRL location, fixation stability, fixation pattern orientation, reading acuity, critical print size, and reading speed.

RESULTS

Out of 30 cases who received BT, only those with age-related macular degeneration and visual acuity of logMAR 0.8 (20/126) or poorer showed a visual acuity gain (statistically significant of 12 letters) after BT. Those with other diagnoses and those with residual Early Treatment Diabetic Retinopathy Study best-corrected visual acuity of logMAR of 0.7 (20/100) or better showed only positive trends for visual acuity and a negative trend for fixation stability. All subjects showed a shift in PRL location toward the superior quadrant of the retina (p < 0.02) in those who received BT.

CONCLUSION

BT seems to offer patients a unique and efficient modality to improve distance vision outside of using optical devices.

Family Functioning and Low Vision: A Systematic Review

This review highlights the literature on the function and adjustment process of family members of persons with adult-onset vision loss. The majority of the literature has focused on the unique role that the family plays in providing both instrumental and emotional support to adults with low vision. In contrast, the impact of low vision on the psychosocial adjustment of the family has been largely understudied. The review concludes with a discussion of the implications for clinical practice, along with directions for future research on the family within the context of low vision rehabilitation.