Effect of a home visit-based low vision rehabilitation intervention on visual function outcomes: an exploratory randomized controlled trial

Purpose: To examine the effect of a home visit–based visual rehabilitation intervention on: (1) self-reported visual function and (2) depression, wellbeing, loneliness, adjustment to visual loss, and generic health-related quality of life. Methods: In an exploratory, assessor-masked, individually randomized, single-center controlled trial, 67 participants (age: 75.22 ± 16.21 years) with low vision were allocated either to receive the home visit–based visual rehabilitation intervention (n = 35) or to a waiting list control arm (n = 32). Outcome measures were collected by telephone interview at baseline and 6 months later. The primary outcome measure was the 48-item Veterans Affairs Low Vision Visual Functioning Questionnaire (VA LV VFQ-48). Secondary outcome measures were: the Patient Health Questionnaire; the Warwick-Edinburgh Mental Well-being Scale, the Adjustment to Age-related Visual Loss Scale, the standardized health-related quality of life questionnaire, and the University of California, Los Angeles Loneliness Scale. Questionnaire scores at follow-up were analyzed using analysis of covariance, controlling for the baseline score and the variables, age, number of comorbidities, visual acuity, and baseline wellbeing score. Results: Visual function (VA LV VFQ-48) improved at follow-up in both groups, with a significantly greater improvement demonstrated by the intervention group (95% confidence interval, 0.33–0.68 logits, P = 0.031), with a moderate effect size (0.55). Secondary outcomes did not indicate any statistically significant differences between groups. Conclusions: The study provides preliminary evidence that a home visit–based visual rehabilitation intervention has a positive influence on vision-related functional outcomes. A larger trial with an expanded intervention to include a mental health component and cost-effectiveness analysis is needed

Ability of head-mounted display technology to improve mobility in people with low vision: a systematic review

Purpose: The purpose of this study was to undertake a systematic literature review on how vision enhancements, implemented using head-mounted displays (HMDs), can improve mobility, orientation, and associated aspects of visual function in people with low vision. Methods: The databases Medline, Chinl, Scopus, and Web of Science were searched for potentially relevant studies. Publications from all years until November 2018 were identified based on predefined inclusion and exclusion criteria. The data were tabulated and synthesized to produce a systematic review. Results: The search identified 28 relevant papers describing the performance of vision enhancement techniques on mobility and associated visual tasks. Simplifying visual scenes improved obstacle detection and object recognition but decreased walking speed. Minification techniques increased the size of the visual field by 3 to 5 times and improved visual search performance. However, the impact of minification on mobility has not been studied extensively. Clinical trials with commercially available devices recorded poor results relative to conventional aids. Conclusions: The effects of current vision enhancements using HMDs are mixed. They appear to reduce mobility efficiency but improved obstacle detection and object recognition. The review highlights the lack of controlled studies with robust study designs. To support the evidence base, well-designed trials with larger sample sizes that represent different types of impairments and real-life scenarios are required. Future work should focus on identifying the needs of people with different types of vision impairment and providing targeted enhancements. Translational Relevance: This literature review examines the evidence regarding the ability of HMD technology to improve mobility in people with sight loss

Electrophysiological ON and OFF responses in autosomal dominant optic atrophy

Purpose To assess the effect of ADOA on the ON and OFF components of the photopic negative response (PhNR). Methods Twelve participants from 6 families with OPA1 ADOA and 16 age matched controls were recruited. Electrophysiological assessment involved long flash focal (20o) and full field ERGs using red flash (664 nm, 250 msec, 55 cd/m2, 2 Hz) on a rod saturating blue background (454 nm, 100 scot cd/m2); and brief xenon flash ERGs using red filter (Lee Filter “Terry Red”, max 300 µs flash duration, 1.69 cd.s.m-2, 4 Hz) over a continuous rod saturating blue background (Schott Glass Filter BG28, 206 scot cd/m2). Amplitudes (from peak and baseline to fixed time point) and implicit times of the ERG components were analysed. Results Mean amplitude (peak to fixed time) of the focal PhNR-ON were significantly (p < 0.05) reduced by 40% while the focal PhNR-OFF was completely eliminated. In the long duration full field ERG, the PhNR-ON and –OFF were reduced by 21% and 57% respectively. Subtraction of the grand averaged ERG of ADOA participants from that of the controls produced a difference plot with a nearly symmetrical loss in the PhNR-ON and OFF components of the focal ERG. ROC curve analysis showed focal PhNR-ON and OFF amplitudes performed better than their full field counterparts. Conclusions We show that OFF components of the photopic ERG were more severely affected in ADOA than ON components. Additionally, the focal PhNR-ON and –OFF components were more effective in assessing ADOA than their full field components

Microperimetry in age-related macular degeneration: an evidence-base for Pattern Deviation probability analysis in microperimetry

Purpose: The “traffic light” color designation of differential light sensitivity used in a number of microperimeters does not encompass the conventional Total and Pattern Deviation probability analyses adopted by standard automated perimetry. We determined whether the color designation is indicative of abnormality as represented by the “gold standard” Pattern Deviation probability analysis. Methods: Total and Pattern Deviation probability levels, using two different methods, were derived at each of 40 stimulus locations, within 7° eccentricity, from 66 ocular healthy individuals (66 eyes) who had undergone microperimetry with the Macular Integrity Assessment microperimeter. The probability levels were applied to the corresponding fields from each of 45 individuals (45 eyes) with age-related macular degeneration (AMD) and evaluated in relation to the color designation. Results: Sensitivities designated in orange encompassed the entire range of Pattern Deviation probability levels (from normal to P ≤ 1%). Those designated in green were mostly normal; those in red/black generally corresponded to the ≤1% probability level. Conclusions: The green and the red/black designations are generally indicative of normal and abnormal probability values, respectively. The orange designation encompassed all probability outcomes and should not be relied upon for visual field interpretation. The evidence base indicates replacement of the color designation of sensitivity in AMD by Total Deviation and Pattern Deviation analyses. Translational Relevance: The use of Total and Pattern Deviation probability analyses is not universal in all microperimeters, and the derivation of these values indicates that color coding will lead to errors in evaluating visual field loss

Depressive symptoms in people with vision impairment: a cross-sectional study to identify who is most at risk

Objective: To identify the risk factors for significant depressive symptoms in people with visual impairment in England and Wales to provide information on who is most at risk and to whom support services could be targeted in future. Design: A cross-sectional study using baseline data from a pragmatic randomised controlled trial. Setting and participants: 990 participants aged 18 or over attending 1 of 14 low-vision rehabilitation primary care optometry-based clinics in South Wales or two hospital clinics in London. Outcome measure: A score of ≥6 on the Geriatric Depression Scale-15 was classed as clinically significant depressive symptoms. Results: In a multivariable logistic regression model, significant depressive symptoms were associated with age (adjusted OR (AOR)=0.82, 95% CI: 0.66 to 0.90, p&lt;0.001), ethnicity (AOR non-white compared with white=1.72, 95% CI: 1.05 to 2.81, p=0.031), total number of eye conditions (AOR for two vs one condition=0.98, 95% CI: 0.67 to 1.43; three or more vs one condition=0.34, 95% CI: 0.15 to 0.75, p=0.026), self-reported health (AOR for excellent vs poor=0.01, 95% CI: 0.00 to 0.12; very good vs poor=0.06, 95% CI: 0.03 to 0.13; good vs poor=0.14, 95% CI: 0.08 to 0.24; fair vs poor=0.28, 95% CI: 0.18 to 0.46, p&lt;0.001) and self-reported visual functioning (AOR=1.45, 95% CI: 1.31 to 1.61, p&lt;0.001). Conclusion: Younger age, a non-white ethnicity, fewer eye conditions and poorer self-reported health and visual function are risk factors for significant depressive symptoms in this population. Trial registration number: ISRCTN46824140; Pre-results

The depression in visual impairment trial (DEPVIT): trial design and protocol

&lt;b&gt;Background&lt;/b&gt; The prevalence of depression in people with a visual disability is high but screening for depression and referral for treatment is not yet an integral part of visual rehabilitation service provision. One reason for this may be that there is no good evidence about the effectiveness of treatments in this patient group. This study is the first to evaluate the effect of depression treatments on people with a visual impairment and co morbid depression.&lt;p&gt;&lt;/p&gt; &lt;b&gt;Methods/design&lt;/b&gt; The study is an exploratory, multicentre, individually randomised waiting list controlled trial. Participants will be randomised to receive Problem Solving Therapy (PST), a ‘referral to the GP’ requesting treatment according to the NICE’s ‘stepped care’ recommendations or the waiting list arm of the trial. The primary outcome measure is change (from randomisation) in depressive symptoms as measured by the Beck’s Depression Inventory (BDI-II) at 6 months. Secondary outcomes include change in depressive symptoms at 3 months, change in visual function as measured with the near vision subscale of the VFQ-48 and 7 item NEI-VFQ at 3 and 6 months, change in generic health related quality of life (EQ5D), the costs associated with PST, estimates of incremental cost effectiveness, and recruitment rate estimation.&lt;p&gt;&lt;/p&gt; &lt;b&gt;Discussion&lt;/b&gt; Depression is prevalent in people with disabling visual impairment. This exploratory study will establish depression screening and referral for treatment in visual rehabilitation clinics in the UK. It will be the first to explore the efficacy of PST and the effectiveness of NICE’s ‘stepped care’ approach to the treatment of depression in people with a visual impairment.&lt;p&gt;&lt;/p&gt

Functional Imaging of the Outer Retinal Complex using High Fidelity Imaging Retinal Densitometry

We describe a new technique, high fdelity Imaging Retinal Densitometry (IRD), which probes the functional integrity of the outer retinal complex. We demonstrate the ability of the technique to map visual pigment optical density and synthesis rates in eyes with and without macular disease. A multispectral retinal imaging device obtained precise measurements of retinal refectance over space and time. Data obtained from healthy controls and 5 patients with intermediate AMD, before and after photopigment bleaching, were used to quantify visual pigment metrics. Heat maps were plotted to summarise the topography of rod and cone pigment kinetics and descriptive statistics conducted to highlight diferences between those with and without AMD. Rod and cone visual pigment synthesis rates in those with AMD (v=0.043SD 0.019min−1 and v=0.119SD 0.046min−1, respectively) were approximately half those observed in healthy controls (v=0.079SD 0.024min−1 for rods and v=0.206SD 0.069min−1 for cones). By mapping visual pigment kinetics across the central retina, high fdelity IRD provides a unique insight into outer retinal complex function. This new technique will improve the phenotypic characterisation, diagnosis and treatment monitoring of various ocular pathologies, including AMD

Effect of rehabilitation worker input on visual function outcomes in individuals with low vision: study protocol for a randomised controlled trial

BACKGROUND: Visual Rehabilitation Officers help people with a visual impairment maintain their independence. This intervention adopts a flexible, goal-centred approach, which may include training in mobility, use of optical and non-optical aids, and performance of activities of daily living. Although Visual Rehabilitation Officers are an integral part of the low vision service in the United Kingdom, evidence that they are effective is lacking. The purpose of this exploratory trial is to estimate the impact of a Visual Rehabilitation Officer on self-reported visual function, psychosocial and quality-of-life outcomes in individuals with low vision. METHODS/DESIGN: In this exploratory, assessor-masked, parallel group, randomised controlled trial, participants will be allocated either to receive home visits from a Visual Rehabilitation Officer (n = 30) or to a waiting list control group (n = 30) in a 1:1 ratio. Adult volunteers with a visual impairment, who have been identified as needing rehabilitation officer input by a social worker, will take part. Those with an urgent need for a Visual Rehabilitation Officer or who have a cognitive impairment will be excluded. The primary outcome measure will be self-reported visual function (48-item Veterans Affairs Low Vision Visual Functioning Questionnaire). Secondary outcome measures will include psychological and quality-of-life metrics: the Patient Health Questionnaire (PHQ-9), the Warwick-Edinburgh Mental Well-being Scale (WEMWBS), the Adjustment to Age-related Visual Loss Scale (AVL-12), the Standardised Health-related Quality of Life Questionnaire (EQ-5D) and the UCLA Loneliness Scale. The interviewer collecting the outcomes will be masked to the group allocations. The analysis will be undertaken on a complete case and intention-to-treat basis. Analysis of covariance (ANCOVA) will be applied to follow-up questionnaire scores, with the baseline score as a covariate. DISCUSSION: This trial is expected to provide robust effect size estimates of the intervention effect. The data will be used to design a large-scale randomised controlled trial to evaluate fully the Visual Rehabilitation Officer intervention. A rigorous evaluation of Rehabilitation Officer input is vital to direct a future low vision rehabilitation strategy and to help direct government resources. TRIAL REGISTRATION: The trial was registered with ( ISRCTN44807874 ) on 9 March 2015

How effective is low vision service provision? A systematic review

Visual impairment is a large and growing socioeconomic problem. Good evidence on rehabilitation outcomes is required to guide service development and improve the lives of people with sight loss. Of the 478 potentially relevant articles identified, only 58 studies met our liberal inclusion criteria, and of these only 7 were randomized controlled trials. Although the literature is sufficient to confirm that rehabilitation services result in improved clinical and functional ability outcomes, the effects on mood, vision-related quality of life (QoL) and health-related QoL are less clear. There are some good data on the performance of particular types of intervention, but almost no useful data about outcomes in children, those of working age, and other groups. There were no reports on cost effectiveness. Overall, the number of well-designed and adequately reported studies is pitifully small; visual rehabilitation research needs higher quality research. We highlight study design and reporting considerations and suggest a future research agenda