Objectives Visual acuity is a common measurement in general practice, and the advent of new technology such as tablet computers offers a change in the way in which these tests are delivered. The aim of this study was to assess whether measurements of distance visual acuity using LogMAR letter charts displayed on an iPad tablet computer were in agreement with standard clinical tests of visual acuity in adults with normal vision. Design Blinded, diagnostic test study. Setting Single centre (University) in Auckland, New Zealand. Participants University staff and students (n=85). Participants were required to have visual acuity better than 6/60 and wear habitual refractive correction during testing. Participants were excluded if there was any history of ocular pathology. Primary and secondary outcome measures Visual acuity measured under a number of conditions. Results The iPad tablet with its glossy screen was highly susceptible to glare resulting in acuity measurements that were significantly poorer (approximately 2 LogMAR lines) than those made using an ETDRS chart and a standard computerised testing system (n=56). However, fitting the iPad with an antiglare screen and positioning the device away from sources creating reflected (veiling) glare resulted in acuity measurements that were equivalent those made using gold standard charts (n=29). Conclusions Tablet computers are an attractive option for visual acuity measurement due to portability, the ability to randomise letters, automated scoring of acuity and the ability to select from a range of charts. However, these devices are only suitable for use in situations where sources of glare can be eliminated.
Nutritional intake can promote early neonatal brain development in very preterm born neonates (< 32 weeks’ gestation). In a group of 7-year-old very preterm born children followed since birth, we examined whether early nutrient intake in the first weeks of life would be associated with long-term brain function and neurocognitive skills at school age. Children underwent resting-state functional MRI (fMRI), intelligence testing (Wechsler Intelligence Scale for Children, 5th Ed) and visual-motor processing (Beery-Buktenica, 5th Ed) at 7 years. Relationships were assessed between neonatal macronutrient intakes, functional connectivity strength between thalamic and default mode networks (DMN), and neuro-cognitive function using multivariable regression. Greater functional connectivity strength between thalamic networks and DMN was associated with greater intake of protein in the first week (β = 0.17; 95% CI 0.11, 0.23, p < 0.001) but lower intakes of fat (β = − 0.06; 95% CI − 0.09, − 0.02, p = 0.001) and carbohydrates (β = − 0.03; 95% CI − 0.04, − 0.01, p = 0.003). Connectivity strength was also associated with protein intake during the first month (β = 0.22; 95% CI 0.06, 0.37, p = 0.006). Importantly, greater thalamic-DMN connectivity strength was associated with higher processing speed indices (β = 26.9; 95% CI 4.21, 49.49, p = 0.02) and visual processing scores (β = 9.03; 95% CI 2.27, 15.79, p = 0.009). Optimizing early protein intake may contribute to promoting long-term brain health in preterm-born children.
Amblyopia is a common neurodevelopmental disorder of vision that is characterised by visual impairment in one eye and compromised binocular visual function. Existing evidence-based treatments for children include patching the nonamblyopic eye to encourage use of the amblyopic eye. Currently there are no widely accepted treatments available for adults with amblyopia. The aim of this trial is to assess the efficacy of a new binocular, videogame-based treatment for amblyopia in older children and adults. We hypothesise that binocular treatment will significantly improve amblyopic eye visual acuity relative to placebo treatment. The BRAVO study is a double-blind, randomised, placebo-controlled multicentre trial to assess the effectiveness of a novel videogame-based binocular treatment for amblyopia. One hundred and eight participants aged 7 years or older with anisometropic and/or strabismic amblyopia (defined as ≥0.2 LogMAR interocular visual acuity difference, ≥0.3 LogMAR amblyopic eye visual acuity and no ocular disease) will be recruited via ophthalmologists, optometrists, clinical record searches and public advertisements at five sites in New Zealand, Canada, Hong Kong and Australia. Eligible participants will be randomised by computer in a 1:1 ratio, with stratification by age group: 7–12, 13–17 and 18 years and older. Participants will be randomised to receive 6 weeks of active or placebo home-based binocular treatment. Treatment will be in the form of a modified interactive falling-blocks game, implemented on a 5th generation iPod touch device viewed through red/green anaglyphic glasses. Participants and those assessing outcomes will be blinded to group assignment. The primary outcome is the change in best-corrected distance visual acuity in the amblyopic eye from baseline to 6 weeks post randomisation. Secondary outcomes include distance and near visual acuity, stereopsis, interocular suppression, angle of strabismus (where applicable) measured at baseline, 3, 6, 12 and 24 weeks post randomisation. Treatment compliance and acceptability will also be assessed along with quality of life for adult participants. The BRAVO study is the first randomised controlled trial of a home-based videogame treatment for older children and adults with amblyopia. The results will indicate whether a binocular approach to amblyopia treatment conducted at home is effective for patients aged 7 years or older. This trial was registered in Australia and New Zealand Clinical Trials Registry ( ACTRN12613001004752 ) on 10 September 2013.
Purpose Globally, there are ~370 million Indigenous peoples. Indigenous peoples typically experience worse health compared with non-Indigenous people, including higher rates of avoidable vision impairment. Much of this gap in eye health can be attributed to barriers that impede access to eye care services. We conducted a scoping review to identify and summarise service delivery models designed to improve access to eye care for Indigenous peoples in high-income countries. Methods Searches were conducted on MEDLINE, Embase and Global Health in January 2019 and updated in July 2020. All study designs were eligible if they described a model of eye care service delivery aimed at populations with over 50% Indigenous peoples. Two reviewers independently screened titles, abstracts and full-text articles and completed data charting. We extracted data on publication details, study context, service delivery interventions, outcomes and evaluations, engagement with Indigenous peoples and access dimensions targeted. We summarised findings descriptively following thematic analysis. Results We screened 2604 abstracts and 67 studies fulfilled our eligibility criteria. Studies were focused on Indigenous peoples in Australia (n=45), USA (n=11), Canada (n=7), New Zealand (n=2), Taiwan (n=1) and Greenland (n=1). The main disease focus was diabetic retinopathy (n=30, 45%), followed by ‘all eye care’ (n=16, 24%). Most studies focused on targeted interventions to increase availability of services. Fewer than one-third of studies reported involving Indigenous communities when designing the service. 41 studies reflected on whether the model improved access, but none undertook rigorous evaluation or quantitative assessment. Conclusions The geographical and clinical scope of service delivery models to improve access to eye care for Indigenous peoples in high-income countries is narrow, with most studies focused on Australia and services for diabetic retinopathy. More and better engagement with Indigenous communities is required to design and implement accessible eye care services.
The purpose of this study was to use functional magnetic resonance imaging (fMRI) to investigate the response of the visual cortex to unilateral primary open-angle glaucoma (POAG). Specifically, we assessed whether regions of V1 and V2 with lost input from the glaucomatous eye had a greater response to input from the nonaffected fellow eye. Nine participants with unilateral POAG causing paracentral visual field defects and four controls participated in the study. We found no evidence for an increased response to the fellow eye in glaucoma-affected regions of the visual cortex; however, in agreement with previous studies, there was a pronounced, retinotopically localized reduction of activation in both the primary (V1) and extrastriate visual cortex (V2), when participants viewed through their glaucomatous eye. Our results suggest a remarkable level of stability within the adult primary and extrastriate visual cortex in response to unilateral neurodegeneration of the optic nerve.