Blue-light filtering spectacle lenses for visual performance, sleep, and macular health in adults

This is a protocol for a Cochrane Review (Intervention). The objectives are as follows: To assess whether blue-light filtering spectacle lenses impart effects on visual function, provide protection to the macula, or both. We will also examine potential effects on the sleep-wake cycle

Nutrition and Eye Health

Diet is a key lifestyle factor that can have long-term effects on ocular health [...]

Transmission of Predictable Sensory Signals to the Cerebellum via Climbing Fiber Pathways Is Gated during Exploratory Behavior

International audiencePathways arising from the periphery that target the inferior olive [spino-olivocerebellar pathways (SOCPs)] are a vital source of information to the cerebellum and are modulated (gated) during active movements. This limits their ability to forward signals to climbing fibers in the cerebellar cortex. We tested the hypothesis that the temporal pattern of gating is related to the predictability of a sensory signal. Low-intensity electrical stimulation of the ipsilateral hindlimb in awake rats evoked field potentials in the C1 zone in the copula pyramidis of the cerebellar cortex. Responses had an onset latency of 12.5 +/- 0.3 ms and were either short or long duration (8.7 +/- 0.1 vs 31.2 +/- 0.3 ms, respectively). Both types of response were shown to be mainly climbing fiber in origin and therefore evoked by transmission in hindlimb SOCPs. Changes in response size (area of field, millivolts per millisecond) were used to monitor differences in transmission during rest and three phases of rearing: phase 1, rearing up; phase 2, upright; and phase 3, rearing down. Responses evoked during phase 2 were similar in size to rest but were smaller during phases 1 and 3, i.e., transmission was reduced during active movement when self-generated (predictable) sensory signals from the hindlimbs are likely to occur. To test whether the pattern of gating was related to the predictability of the sensory signal, some animals received the hindlimb stimulation only during phase 2. Over similar to 10 d, the responses became progressively smaller in size, consistent with gating-out transmission of predictable sensory signals relayed via SOCPs

Efficacy of Coloured Overlays and Lenses for the Treatment of Reading Difficulty: An Overview of Systematic Reviews

Background Coloured overlays or lenses are widely available for use by children and adults with difficulties or discomfort while reading. In recent years, systematic reviews have been conducted in an attempt to establish the strength of the evidence base for this intervention. The aims of this overview is to systematically review these reviews. Method The methodology was published prospectively as a protocol (Prospero CRD42017059172). Online databases Medline, Cinahl, Ovid and the Cochrane library were searched for systematic reviews on the efficacy of coloured overlays or lenses for the alleviation of reading difficulty or discomfort. Included studies were appraised using the AMSTAR 2 checklist. Characteristics of included studies including aspects of methods, results and conclusions were recorded. Both processes were conducted independently by two reviewers and any discrepancies were resolved by discussion. Results Thirty-one studies were found via databases and other sources. After excluding duplicates and those not fitting the inclusion criteria, four reviews were included in the analysis. While all reviews were systematic, their methodology, results and conclusions differed. Three of the four concluded that there is insufficient good quality evidence to support the use of coloured overlays or lenses for reading difficulty, while one concluded that, despite research limitations, the evidence does support their use. Conclusions On balance, systematic reviews to date indicate that there is not yet a reliable evidence base on which to recommend coloured overlays or lenses for the alleviation of reading difficulty or discomfort. High quality, low bias research is needed to investigate their effectiveness in different forms of reading difficulty and discomfort for adults and children

Evaluation of a new rebound tonometer for self-measurement of intraocular pressure

Background/aims To compare the accuracy of self-obtained, partner-obtained and trainer-obtained measurements using the handheld Icare Home rebound tonometer with Goldmann applanation tonometry (GAT), and to evaluate the acceptability to subjects of Icare Home measurement. Methods 76 subjects were trained to use Icare Home for self-measurement using a standardised protocol. A prespecified checklist was used to assess the ability of a subject to perform self-tonometry. Accuracy of Icare Home self-measurement was compared with GAT using one eye per subject, randomly selected. Bland-Altman difference analysis was used to compare Icare Home and GAT intraocular pressure (IOP) estimates. Acceptability of self-tonometry was evaluated using a questionnaire. Results 56 subjects (74%, 95% CI 64 to 84) were able to correctly perform self-tonometry. Mean bias (95% limits of agreement) was 0.3 mm Hg (−4.6 to 5.2), 1.1 mm Hg (−3.2 to 5.3) and 1.2 mm Hg (−3.9 to 6.3) for self-assessment, partner-assessment and trainer-assessment, respectively, suggesting underestimation of IOP by Icare Home tonometry. Differences between GAT and Icare Home IOP were greater for central corneal thickness below 500 µm and above 600 µm than data points within this range. Acceptability questionnaire responses showed high agreement that the self-pressure device was easy to use (84%), the reading was quick to obtain (88%) and the measurement was comfortable (95%). Conclusions Icare Home tonometry can be used for self-measurement by a majority of trained subjects. IOP measurements obtained using Icare Home tonometry by self-assessment and third party-assessment showed slight underestimation compared with GAT

A Critical Appraisal of National and International Clinical Practice Guidelines Reporting Nutritional Recommendations for Age-Related Macular Degeneration: Are Recommendations Evidence-Based?

Eye care professionals should have access to high quality clinical practice guidelines that ideally are underpinned by evidence from robust systematic reviews of relevant research. The aim of this study was to identify clinical guidelines with recommendations pertaining to dietary modification and/or nutritional supplementation for age-related macular degeneration (AMD), and to evaluate the overall quality of the guidelines using the Appraisal of Guidelines for Research and Evaluation II (AGREE II) instrument. We also mapped recommendations to existing systematic review evidence. A comprehensive search was undertaken using bibliographic databases and other electronic resources for eligible guidelines. Quality appraisal was undertaken to generate scores for each of the six AGREE II domains, and mapping of extracted nutritional recommendations was performed for systematic reviews published up to March 2017. We identified 13 national and international guidelines, developed or updated between 2004 and 2019. These varied substantially in quality. The lowest scoring AGREE II domains were for 'Rigour of Development', 'Applicability' (which measures implementation strategies to improve uptake of recommendations), and 'Editorial Independence'. Only four guidelines used evidence from systematic reviews to support their nutritional recommendations. In conclusion, there is significant scope for improving current Clinical Practice Guidelines for AMD, and guideline developers should use evidence from existing high quality systematic reviews to inform clinical recommendations

Noncontact Screening Methods for the Detection of Narrow Anterior Chamber Angles

PURPOSE: Comparing diagnostic accuracy of biomicroscope techniques (van Herick and Smith's tests, evaluating limbal and central anterior chamber depth, respectively) and advanced imaging (Visante OCT and Pentacam) for detection of gonioscopically narrow anterior chamber angles (ACAs). METHODS: A total of 78 subjects with narrow or open ACAs underwent four index tests, performed on both eyes by examiners masked to other test results. Diagnostic performance was compared with gonioscopy, using International Society of Geographical and Epidemiological Ophthalmology (ISGEO) definition of primary angle closure and a classification based on clinical opinion of occludability. Data were analyzed using both the eye and the individual as unit of analysis. Sensitivity, specificity, and partial area under the receiver operating characteristic curve (AUROC) were generated. RESULTS: Using the eye as the unit of analysis, the van Herick grading cutoff of 25% or less and ISGEO gonioscopic classification achieved 80% (confidence interval [CI] 65 to 89) sensitivity and 92% specificity (CI 80 to 97) for narrow angle detection, with specificity reaching 97% (CI 87 to 100) for a cutoff of less than or equal to 15%. Notably, with a gonioscopic classification based on clinical opinion of occludability, van Herick (≤25%) together with Smith's test (≤2.50 mm) detected 100% of narrow angle subjects. Of the three Pentacam parameters, anterior chamber volume achieved highest test sensitivity of 85% (CI 70 to 94) using the ISGEO definition. Visante OCT ACA had greatest partial AUROC at 90% specificity, also yielding sensitivity and specificity greater than 85% using the Youden-derived cutoff of less than or equal to 20.7°and ISGEO definition. CONCLUSIONS: Van Herick test and Visante OCT ACA exhibited best discrimination between narrow and open angles both alone, and in combination. Van Herick test affords advantages over Visante OCT, showing potential for identifying individuals who may benefit from further gonioscopic assessment in a case-finding or screening setting

Diagnostic accuracy of technologies for glaucoma case-finding in a community setting

DESIGN: Cross-sectional, observational, community-based study. PARTICIPANTS: A total of 505 subjects aged ≥60 years recruited from a community setting using no predefined exclusion criteria. METHODS: Subjects underwent 4 index tests conducted by a technician unaware of subjects' ocular status. FDT and MMDT were used in suprathreshold mode. iVue OCT measured ganglion cell complex and retinal nerve fiber layer (RNFL) thickness. Reference standard was full ophthalmic examination by an experienced clinician who was masked to index test results. Subjects were classified as POAG (open drainage angle, glaucomatous optic neuropathy, and glaucomatous field defect), glaucoma suspect, ocular hypertension, or non-POAG/nonocular hypertension. MAIN OUTCOME MEASURES: Test performance evaluated the individual as the unit of analysis. Diagnostic accuracy was assessed using predefined cutoffs for abnormality, generating sensitivity, specificity, and likelihood ratios. Continuous data were used to derive estimates of sensitivity at 90% specificity and partial area under the receiver operating characteristic curve (AUROC) plots from 90% to 100% specificity. RESULTS: From the reference standard examination, 26 subjects (5.1%) had POAG and 32 subjects (6.4%) were glaucoma suspects. Sensitivity (95% confidence interval) at 90% specificity for detection of glaucoma suspect/POAG combined was 41% (28-55) for FDT, 35% (21-48) for MMDT, and 57% (44-70) for best-performing OCT parameter (inferior quadrant RNFL thickness); for POAG, sensitivity was 62% (39-84) for FDT, 58% (37-78) for MMDT, and 83% (68-98) for inferior quadrant RNFL thickness. Partial AUROC was significantly greater for inferior RNFL thickness than visual-function tests (P < 0.001). Post-test probability of glaucoma suspect/POAG combined and definite POAG increased substantially when best-performing criteria were combined for FDT or MMDT, iVue OCT, and ORA. CONCLUSIONS: Diagnostic performance of individual tests gave acceptable accuracy for POAG detection. Low specificity of visual-function tests precludes their use in isolation, but case detection improves by combining RNFL thickness analysis with visual function tests