Visual performance, safety, and patient satisfaction after binocular clear lens extraction and trifocal intraocular lens implantation in Chinese presbyopic patients.

BACKGROUND: Addressing presbyopia in the aging population, particularly in non-cataractous patients, remains a challenge. This study evaluates the outcomes of refractive lens exchange (RLE) with AT LISA tri 839MP trifocal intraocular lens (IOL) implantation in a Chinese presbyopic population without cataracts. METHODS: The study included 164 eyes from 82 patients undergoing bilateral RLE at Peking Union Medical College Hospital. Comprehensive evaluations encompassed visual acuities, refraction, ocular aberrometry, and subjective outcomes via the VF-14 questionnaire. The focus was on postoperative visual performance, refractive outcomes, safety, objective optical quality, and patient satisfaction. RESULTS: 100%, 90.2%, and 89.0% of patients achieved binocular UDVA, UNVA, and UIVA of logMAR 0.1 or better at 6 months postoperatively. 97.6% of eyes were within ± 1.00 D of emmetropia postoperatively. Optical quality assessments showed increases in modulation transfer function and Strehl ratios (p < 0.05). High-order aberrations decreased significantly (p < 0.05). Despite the high incidence of posterior capsule opacification (83.2%), managed with early Nd: YAG capsulotomy, no other severe complications were reported. Patient-reported outcomes indicated high satisfaction, with an average VF-14 score of 94.3 ± 10.2 and 93.5% achieving complete spectacle independence. Halo (66.2%) was the most commonly reported optical phenomena, followed by glare (18.2%), and starburst (7.8%) after surgery. CONCLUSIONS: Bilateral RLE with trifocal IOLs in presbyopic patients without cataracts significantly improves visual acuity and reduces ocular aberrations in presbyopic patients. The procedure offers high patient satisfaction and spectacle independence, though it requires careful patient selection and management of expectations regarding potential photic phenomena.

Effect of myopia-control lenses on central and peripheral visual performance in myopic children.

PURPOSE: To evaluate the short-term effects of three myopia-control lenses, which impose peripheral myopic defocus while providing clear central vision, on central and peripheral visual performance in myopic children. METHODS: Twenty-one myopic children were enrolled in the study. Central visual performance was assessed using the quick contrast sensitivity function. Peripheral visual performance was evaluated by measuring peripheral contrast threshold and global motion perception, while subjects maintained fixation through the central portion of the lens. Single-vision spectacle lenses (SVL), spectacle lenses with highly aspherical lenslets (HAL) and defocus-incorporated soft contact (DISC) lenses were evaluated in random order, followed by orthokeratology (OK) lenses. All tests were performed monocularly on the right eye. RESULTS: The area under the log contrast sensitivity function (AULCSF) with DISC lenses was lower than that with SVL (1.14 vs. 1.40, p < 0.001) and HAL (1.14 vs. 1.33, p = 0.001). HAL increased the temporal visual field contrast threshold compared with OK lenses (p = 0.04), and OK lenses decreased the superior visual field contrast threshold compared with that of SVL (p = 0.04) and HAL (p = 0.005). HAL also increased the peripheral coherence threshold for identifying the contraction movement compared with OK lenses (p = 0.01). CONCLUSIONS: The short-term use of these optical interventions for myopia control exhibited measurable differences in central and peripheral visual performance. Relevant attention could be paid to these differences, especially when children switch to different treatments. DISC lenses exhibited worse central contrast sensitivity than SVL and HAL. Imposing peripheral defocus signals did not affect children's peripheral visual performance compared with SVL. However, considering the poorer peripheral visual performance provided by HAL, OK lenses are recommended for children if there are specific demands for global scene recognition and motion perception.

Soft toric contact lens wear improves digital performance and vision-A randomised clinical trial.

PURPOSE: To compare objective and subjective digital near visual performance and comfort in low to moderate astigmatic participants fitted with toric versus spherical equivalent silicone hydrogel daily disposable contact lenses. METHODS: This was a double-masked, randomised, crossover study. Participants aged 18 to 39 years with astigmatism of -0.75 to -1.50 D were recruited and fitted with toric and spherical contact lenses, in random order. Outcomes were measured at baseline and after 1 week of wear with each contact lens type after the follow-up visits. High- and low-contrast near logMAR visual acuity, automated visual acuity, zoom (%), contrast (%), reading distance (cm), critical print size (logMAR) and reading speed were assessed. Participants also completed the validated Near Activity Visual Questionnaire (NAVQ) and Contact Lens Dry Eye Questionnaire 8 (CLDEQ-8) for each correction type. RESULTS: Twenty-three participants completed the study (74% female, average age 24.4 ± 4.2 years). When participants wore toric contact lenses, near high- and low-contrast visual acuity and automated visual acuity improved by 3-4 letters (all p < 0.03) and participants were able to read faster on an iPad (p = 0.02). Participants were also able to read with 8% less contrast on the iPad with toric lenses (p = 0.01). Participants reported better subjective vision on the overall NAVQ (p = 0.001) and better comfort on the CLDEQ-8 (p = 0.02) with toric lenses. Fewer participants reported difficulty with maintaining focus at near, reading small print, reading labels/instructions, reading the computer display/keyboard and reading post/mail with toric correction. CONCLUSIONS: Toric contact lenses improve comfort, subjective and objective visual performance with digital devices and other near tasks compared with the spherical equivalent correction in participants with low to moderate astigmatism.

Comparison of visual performance between peripheral gradient high-addition multifocal soft contact lenses and orthokeratology.

PURPOSE: The aim of this study was to evaluate the short-term effects of peripheral gradient high-addition multifocal soft contact lenses (MFSCLs) and orthokeratology (Ortho-K lenses) on visual performance in myopic children. METHODS: Thirty myopic children participated in this prospective study. Each participant wore different sets of lenses in the following sequence: single-vision spectacles (SVSPs) as a control, MFSCLs and Ortho-K lenses. Ocular aberrations, topography, high-contrast visual acuity (HCVA), low-contrast visual acuity (LCVA) and accommodation of the right eye were measured with each type of correction on a different day. RESULTS: Compared with SVSPs, high-addition MFSCLs and Ortho-K lenses significantly increased all items of aberrations (all p < 0.05) except trefoil (p = 0.17). MFSCLs induced less coma, root mean square of the third-order aberration (RMS3) and higher order aberrations than Ortho-K lenses (all p < 0.05). No significant difference in HCVA was found across the three correction types (F = 1.19, p = 0.39). In terms of LCVA, MFSCLs performed significantly poorer than SVSPs (difference, 0.16 logMAR; p = 0.001) and slightly worse than Ortho-K lenses (difference, 0.08 logMAR; p = 0.35). No significant difference in decentration was found between the two types of contact lenses, and no associations were observed between decentration and visual acuity at both high- and low-contrast levels (all p > 0.05). For MFSCLs, decentration was positively related to coma (r = 0.43, p = 0.02) and RMS3 (r = 0.44, p = 0.02), which was not the case for Ortho-K lenses. Accommodative facility was worse with MFSCLs than Ortho-K lenses (p = 0.001). CONCLUSION: Multifocal soft contact lenses differed from Ortho-K lenses in aberration profile and LCVA, although decentration was similar. Decentration <1 mm had minimal influence on both HCVA and LCVA for either type of correction, but significantly increased third-order aberrations for MFSCLs, but not Ortho-K lenses.

Longitudinal evaluation of trifocal and extended depth of focus lenses implantation using standard automated perimetry parameters.

PURPOSE: To evaluate reliability and global indices parameters from standard automated perimetry (SAP) in normal eyes undergoing phacoemulsification cataract surgery with implantation of trifocal or extended depth of focus intraocular lens (IOL). METHODS: Prospective study to evaluate the effect of trifocal IOL AcrySof IQ PanOptix® and extended depth of focus intraocular lens (EDOF) Tecnis Symfony® IOL implantation on visual field parameters. Patients underwent SAP pre- and postoperatively. Reliability indices (false negative rate-FN, false positive rate-FP), global indices (foveal sensitivity threshold, visual field index-VFI, standard pattern deviation-PSD, mean deviation MD) and test duration were analyzed. RESULTS: A total of 23 eyes from 13 patients were in the trifocal IOL group and a total of 22 eyes from 14 patients were in the EDOF group. The following results were obtained by analyzing pre- and postoperative SAP of EDOF IOL: the rate of change of FN was 1.95/1.41% (p = 0.61); FP 1.64/1.27 (p = 0.60); MD - 1.60/- 1.08 dB (p = 0.15); foveal sensitivity was 34.5/33.9 dB (p = 0.41); VFI 98.5/98.4% (p > 0.99); PSD 1.85/1.86 (p = 0.07); and for test duration 305.81/298.36 s (p = 0.35); all respectively. Analysis of pre- and postoperative parameters of trifocal IOL were the rates of change of FN 1.22/1.83% (p = 0.29); FP 1.65/1.48% (p = 0.95); MD - 1.55/- 1.37 dB (p = 0.19); foveal sensitivity 33.9/34.9 dB (p = 0.47); VFI 98.6/98.3% (p = 0.62); PSD 1.58/2.05 (p = 0.02); and test duration 297.17/298.57 s (p = 0.87); all respectively. CONCLUSION: We identified a change in the PSD parameters in the trifocal IOL group. No other significant changes were identified in SAP parameters after implantation of trifocal AcrySof IQ PanOptix® and EDOF Tecnis Symfony® IOL. Longitudinal evaluation showed no changes in SAP after Trifocal and EDOF IOL implantation in normal subjects.

Depth of field and visual performance after implantation of a new hydrophobic trifocal intraocular lens.

PURPOSE: To assess the depth of field (DOF) by means of defocus curve analysis applying different visual acuity criteria in patients following cataract surgery and bilateral implantation of a new trifocal diffractive intraocular lens (IOL). METHODS: Fifty eyes of 25 consecutive patients who underwent implantation of the Asqelio™ trifocal IOL (AST Products Inc., USA) were enrolled in this observational prospective study. Monocular subjective DOF was obtained from defocus curves with absolute and relative criteria of tolerance for different visual acuities values. Patient's visual satisfaction, postoperative refraction and visual acuity at far, intermediate (67 cm) and near (40 cm) distances were also measured at 1 and 3-months post-surgery. Analysis of variance was used to assess differences in refractive error after the surgical procedure, and paired t-tests were used to assess differences in VA. Patient satisfaction results were reported as percentages. RESULTS: Spherical equivalent was 0.05 ± 0.23 D and residual cylinder 0.01 ± 0.23 D 3-months after the surgery. Absolute DOF obtained was 3.29 ± 0.91 D considering 0.1 LogMAR as cut-off value, and 4.82 ± 0.69 D when 0.3 logMAR as cutoff value. Relative DOF considering a drop of 0.1 logMAR from maximum visual acuity was 2.57 ± 0.82 D, and 1.27 ± 0.70 D when a drop of 0.04 logMAR was considered. Visual acuities obtained 3-months after the surgery were 0.03 ± 0.13, - 0.05 ± 0.06, 0.03 ± 0.08 and 0.04 ± 0.08 logMAR for uncorrected and best-corrected for distance, and best distance-corrected for intermediate and near distances, respectively. Average response to visual satisfaction queries was 8.24/10 at distance, 8.04/10 at intermediate, and 7.88/10 at near. CONCLUSIONS: Patients implanted with this trifocal IOL showed a significant improvement in visual acuity at different distances providing wide absolute and relative DOF values. The outcomes demonstrate that this lens is predictable yielding good patient satisfaction rates.

Short-term tear film stability, optical quality and visual performance in two dual-focus contact lenses for myopia control with different optical designs.

PURPOSE: To assess and compare short-term visual and optical quality and tear film stability between two dual-focus (DF) prototype myopia control contact lenses (CLs) having different inner zone diameters. METHODS: Twenty-eight myopic subjects were included in this randomised, double-masked crossover study. Refraction, best-corrected visual acuity (VA) and tear film stability were measured at baseline (i.e., when uncorrected). Subjects were then binocularly fitted with the DF CLs, with only the sensorial dominant eye being assessed. Lenses were of the same material and had inner zone diameters of either 2.1 mm (S design) or 4.0 mm (M design). Visual and physical short-term lens comfort, over-refraction, best-corrected VA, stereopsis at 40 cm, best-corrected photopic and mesopic contrast sensitivity (CS), size and shape of light disturbance (LD), wavefront aberrations, subjective quality of vision (QoV Questionnaire) and tear film stability were measured for each lens. RESULTS: Both CL designs decreased tear film stability compared with baseline (p < 0.05). VA and photopic CS were within normal values for the subjects' age with each CL. When comparing lenses, the M design promoted better photopic CS for the 18 cycles per degree spatial frequency (p < 0.001) and better LD (p < 0.02). However, higher-order aberrations were improved with the S design (p = 0.02). No significant difference between the two CLs was found for QoV scores and tear film stability. CONCLUSIONS: Both DF CLs provided acceptable visual performance under photopic conditions. The 4.0 mm inner zone gave better contrast sensitivity at high frequencies and lower light disturbance, while the 2.1 mm central diameter induced fewer higher-order aberrations for a 5 mm pupil diameter. Both CLs produced the same subjective visual short-term lens comfort.

The Disaggregated Effects of Visual Performance Feedback on Teachers' Use of Behavior Specific-Praise and Reprimands.

Behavior-specific praise (BSP) is one of the simplest classroom management strategies to implement and considered an evidence-based practice. Unfortunately, teachers underuse BSP and deliver more reprimands to students in their classrooms. Secondary students receive the highest rates of reprimands and exclusionary discipline (i.e., office discipline referral [ODR], suspension, expulsion) with students of color receiving disproportionate rates compared to their White peers. Performance feedback is a commonly used strategy to change teacher practices however, little is known about the impact of performance feedback on the equitable delivery of BSP and reprimands to students by race and sex. The purpose of this multiple baseline design study was to examine the effects of a visual performance feedback (VPF) intervention with secondary teachers on their equitable delivery of BSP and reprimands and the collateral impacts on student outcomes. In the first phase of intervention, teachers received VPF on their total BSP and reprimands. In the second phase, teachers received disaggregated VPF on their rates of BSP and reprimands delivered to students by race and sex. Results indicate a functional relation between VPF and total BSP and an overall reduction in total reprimands. Mixed results were found between VPF and the equitable delivery of BSP and reprimands rates delivered to students by race and sex. Student outcomes indicated an increase in average class-wide academic engagement and no impact on ODRs as no teacher delivered a single ODR. Key findings, limitations, and future research are discussed.

Parkinson's disease-related changes in the behavioural synergy between eye movements and postural movements.

Patients with Parkinson's disease (PD patients) have been shown to exhibit abnormally low levels of synergy in their posture control. The goal of this study was to determine how synergic interactions between vision and posture are affected in PD patients. These synergic interactions were expected to be impaired because PD affects the basal ganglia, which are involved in the modulation of both types of movement. Twenty patients (mean age: 60) on levodopa and 20 age-matched-controls (mean age: 61) performed a precise visual task (searching for targets in an image) and an unprecise control task (randomly looking at an image) in which images were projected onto a large panoramic display. Lower back, upper back, head and eye movements were recorded simultaneously. To test behavioural synergies, Pearson correlations between eye and postural movements were analysed. The relationships between eye movements and upper and lower back movements were impaired in the patients. The age-matched controls did not show any significant correlations between eye and postural movements. Overall, our results showed that the PD patients failed to adjust and control their postural stability for success in the visual task. The impaired synergy between eye and postural movements was not related to clinical variables-probably because our patients had early-stage PD. Our results showed that impairments in synergy can occur very early in PD. Hence, the analysis of this synergy might provide a better understanding of postural instability, visual task performance in the upright stance, and perhaps the risk of falls in PD patients.

The short-term effects of artificially-impaired binocular vision on driving performance.

Appropriate visual function is paramount to ensuring adequate driving performance and road safety. Here, we examined the influence of sudden artificially-impaired binocular vision on driving performance using a car simulator. Twenty-four young drivers (mean age 22.42 ± 3.19 years) drove under three different visual conditions (natural driving, monocular blur, and monocular occlusion) through three different traffic environments with low, medium, and high levels of complexity (highway, rural, and city, respectively). We assessed their driving performance, perceived level of task complexity, and subjectively-experienced road safety. Furthermore, as a manipulation check, we also evaluated the drivers' cardiac vagal responses, as a well-known index of task complexity. The sudden deterioration of binocular vision caused unsafe driving behaviours (distance out of the road and maximum breaking intensity) in the most complex traffic environments. Specific self-regulatory strategies (i.e. increased cardiac vagal responses) and subjective responses corroborated these results. Practitioner summary: This study provides evidence that the sudden deterioration of binocular vision has a detrimental effect on simulated driving performance. Our analysis of cardiovascular functioning shows that drivers adopt self-regulatory strategies when their binocular vision functioning is compromised. Abbreviations: VA: visual acuity; BV: binocular vision; HRV: heart rate variability; NASA: TLX: NASA-Task Load Index; SSS: Stanford Sleepiness scale; RMSSD: root mean square of successive difference; HF: high-frequency.

Comparison between bilateral implantation of a trifocal intraocular lens (Alcon Acrysof IQ® PanOptix) and extended depth of focus lens (Tecnis® Symfony® ZXR00 lens).

PURPOSE: To compare the visual performance outcomes following bilateral cataract surgery using trifocal intraocular lens (Alcon Acrysof IQ® PanOptix) and extended depth of focus lens (Tecnis® Symfony® ZXR00 lens). METHODS: In this prospective, non-randomized, comparative trial, a total of 40 subjects (80 eyes) were divided into two different groups and submitted to bilateral cataract surgery and implantation of the two different IOLs, Alcon Acrysof IQ® PanOptix® TNFT00 in group A and Tecnis® Symfony® ZXR00 lens (Johnson & Johnson Vision) in group B, was assessed. The uncorrected and corrected near (33 cm), intermediate (60 cm), and far (4 m) binocular visual acuity was measured, and visual binocular defocus curves were also measured in the photopic condition with a long-distance visual acuity and the qualitative visual function was assessed by NEI VFQ-25. RESULTS: Group A comprised 20 patients; 11 women (55%) and 9 men (45%) with a mean age of 62.1 ± 5.4. In group B 20 patients were recruited; 12 women (60%) and 8 men (40%) with a mean age of 63.2 ± 6.1. The postoperatively calculated mean sphere was + 0.35 ± 0.12 D and - 0.14 ± 0.13 D in groups A and B, respectively. The postoperative uncorrected distance visual acuity (UDVA) as well as uncorrected intermediate visual acuity (UIVA) were statistically equal in both groups (P = 0.12, P = 0.17); meanwhile, the postoperative uncorrected near visual acuity (UNVA) was significantly better in patients with PanOptix IOL implantation (P = 0.01) compared to the binocular defocus curve; the results of the PanOptix group were better than the Symfony group in intermediate and near distance (P = 0.089, P = 0.001) and according to the VFQ-25 questionnaire, then ear vision score as well as sum score turned out to be significantly higher in groups A than B (P = 0.001 and P = 0.015, respectively). CONCLUSION: Both strategies were able to provide good vision for far, intermediate and near distances.

Nighttime driving: visual, lighting and visibility challenges.

PURPOSE: Nighttime driving is dangerous and is one of the most challenging driving situations for most drivers. Fatality rates are higher at night than in the day when adjusted for distances travelled, particularly for crashes involving pedestrians and cyclists. Although there are multiple contributory factors, the low light levels at night are believed to be the major cause of collisions with pedestrians and cyclists at night, most likely due to their reduced visibility. Understanding the visibility problems involved in nighttime driving is thus critical, given the increased risk to road safety. RECENT FINDINGS: This review discusses research that highlights key differences in the nighttime road environment compared to the day and how this affects visual function and driving performance, together with an overview of studies investigating how driver age and visual status affect nighttime driving performance. Research that has focused on the visibility of vulnerable road users at nighttime (pedestrians and cyclists) is also included. SUMMARY: Collectively, the research evidence suggests that visual function is reduced under the mesopic lighting conditions of night driving and that these effects are exacerbated by increasing age and visual impairment. Light and glare from road lighting and headlights have significant impacts on vision and night driving and these effects are likely to change with evolving technologies, such as LED streetlighting and headlights. Research also highlights the importance of the visibility of vulnerable road users at night and the role of retroreflective clothing in the 'biomotion' configuration for improving their conspicuity and hence safety.

Comparison of short-term light disturbance, optical and visual performance outcomes between a myopia control contact lens and a single-vision contact lens.

PURPOSE: To compare the optical and visual performance of a dual-focus (DF) contact lens used for myopia control with a single-vision (SV) contact lens of the same material. METHODS: A randomised, double-masked crossover study. Twenty-eight healthy, myopic volunteers between 18 and 32 years of age (23.49 ± 4.07 years) participated in this study. The sensory dominant eye for distance vision was determined. Refraction, best-corrected visual acuity (VA) and aberrations for 3 mm and 5 mm pupil diameters were quantified without a contact lens in situ. Subjects were fitted with two contact lens designs: DF and SV, both made of omafilcon A material. The Quality of Vision (QoV) questionnaire, over-refraction, best-corrected VA, stereopsis at 40 cm, best-corrected photopic and mesopic contrast sensitivity, light disturbance and aberrations were assessed 25 min after contact lens insertion. RESULTS: There were no statistically significant differences in best-corrected VA and stereopsis between the baseline, DF and SV conditions. Photopic and mesopic contrast sensitivity were lower for the DF contact lens at all frequencies, with the exception of the mesopic contrast sensitivity at 18 cycles per degree (p = 0.23). Higher order aberrations and light disturbance size and irregularity were higher for the DF contact lens (p < 0.001). No differences were found in higher order aberrations between baseline and the SV contact lens condition for each pupil diameter. QoV scores also revealed lower frequency, severity and bothersome scores with the SV contact lens than with the DF contact lens (p < 0.001). CONCLUSIONS: The DF contact lens design decreased the psychophysical and psychometric visual quality scores in the short-term under dim-light conditions when compared with a single-vision contact lens design of the same material. VA and stereopsis were unaffected by the lens design.

Postural precursors of motion sickness in head-mounted displays: drivers and passengers, women and men.

Motion sickness is preceded by distinctive patterns of postural activity that differ between the sexes. We asked whether such postural precursors of motion sickness might exist before participants were exposed to a virtual driving game presented via a head-mounted display. Men and women either controlled a virtual vehicle (drivers), or viewed a recording of virtual vehicle motion (passengers). Before exposure to the game, we recorded standing body sway while participants performed simple visual tasks (staring at a blank page vs. counting target letters in a block of text). Following game exposure, participants were classified into Well and Sick groups. In a statistically significant interaction, the multifractality of body sway varied as a function of sex, vehicle control, and motion sickness status. The results confirm that postural precursors of motion sickness differ between the sexes, and extend these to the control of virtual vehicles in head-mounted displays. Practitioner Summary: We asked whether postural sway might predict motion sickness during exposure to a driving game via a head-mounted display. Participants drove a virtual car (drivers), or watched recorded car motion (passengers). Beforehand, we measured standing body sway. Postural precursors of motion sickness differed between the sexes and drivers and passengers. Abbreviations: M: meters; SD: standard deviation; kg: kilograms; COP: centre of pressure; AP: anterior-posterior; ML: mediolateral; cm: centimeters; s: seconds; min: minutes; MF: DFA: multifractal detrended fluctuation analysis; DFA: detrended fluctuation analysis; ANOVA: analysis of variance; CI: confidence interval; Hz: hertz; SE: standard error of the mean.

Supplementation with macular carotenoids improves visual performance of transgenic mice.

Carotenoid supplementation can improve human visual performance, but there is still no validated rodent model to test their effects on visual function in laboratory animals. We recently showed that mice deficient in ß-carotene oxygenase 2 (BCO2) and/or ß-carotene oxygenase 1 (BCO1) enzymes can accumulate carotenoids in their retinas, allowing us to investigate the effects of carotenoids on the visual performance of mice. Using OptoMotry, a device to measure visual function in rodents, we examined the effect of zeaxanthin, lutein, and ß-carotene on visual performance of various BCO knockout mice. We then transgenically expressed the human zeaxanthin-binding protein GSTP1 (hGSTP1) in the rods of bco2-/- mice to examine if delivering more zeaxanthin to retina will improve their visual function further. The visual performance of bco2-/- mice fed with zeaxanthin or lutein was significantly improved relative to control mice fed with placebo beadlets. ß-Carotene had no significant effect in bco2-/- mice but modestly improved cone visual function of bco1-/- mice. Expression of hGSTP1 in the rods of bco2-/-mice resulted in a 40% increase of retinal zeaxanthin and further improvement of visual performance. This work demonstrates that these "macular pigment mice" may serve as animal models to study carotenoid function in the retina.

Retinal-image quality and contrast sensitivity function in eyes with epiretinal membrane: a cross-sectional observational clinical study.

BACKGROUND: To investigate the effect of idiopathic epiretinal membrane (ERM) on the retinal-image quality and psychophysical contrast sensitivity function (CSF). METHODS: Forty-four subjects with diagnosis of idiopathic unilateral ERM were enrolled in this cross-sectional observational clinical study. The fellow unaffected eyes were set as the control group. For retinal-image quality assessment, an Optical Quality Analysis System (OQAS) based on double-pass technique was used to evaluate objective scatter index (OSI) and Strehl ratio. For visual performance, the CSF under photopic condition was measured. RESULTS: For retinal-image quality, the result of double-pass device revealed a significant lower Strehl ratio and larger OSI in the ERM eyes compared to the fellow eyes (all P < 0.05). For visual performance, the CSF at all spatial frequencies under photopic condition were also significantly degraded in the ERM eyes compared to the fellow eyes (all P < 0.05). For the ERM eyes, the reduction of Strehl ratio and CSF was 29.41 and 54.39%, respectively, and the increase of OSI was 164.10% compared to the fellow eyes. Besides, BCVA significantly correlated to the total CSF (ERM eyes, r = - 0.53, P < 0.001; the fellow eyes, r = - 0.467, P = 0.002) and Strehl ratio (ERM eyes, r = - 0.485, P = 0.001; the fellow eyes, r = - 0.311, P = 0.043) in both of the ERM and the fellow eyes. CONCLUSION: Eyes affected with ERM showed poorer retinal-image quality and visual performance than the normal eyes. Retinal-image quality measured by OQAS based on double-pass technique could be useful for assessing the retinal-image quality for ERM-affected eyes, in which retinal scattering was significantly increased.

Dietary guidance for lutein: consideration for intake recommendations is scientifically supported.

Lutein, a yellow xanthophyll carotenoid found in egg yolks and many colorful fruits and vegetables, has gained public health interest for its putative role in visual performance and reducing the risk of age-related macular degeneration. The National Academies of Sciences, Engineering and Medicine's recommended Dietary Reference Intakes (DRIs) focus on preventing deficiency and toxicity, but there is a budding interest in establishing DRI-like guidelines for non-essential bioactives, like lutein, that promote optimal health and/or prevent chronic diseases. Lupton et al. developed a set of nine criteria to determine whether a bioactive is ready to be considered for DRI-like recommendations. These criteria include: (1) an accepted definition; (2) a reliable analysis method; (3) a food database with known amounts of the bioactive; (4) cohort studies; (5) clinical trials on metabolic processes; (6) clinical trials for dose-response and efficacy; (7) safety data; (8) systematic reviews and/or meta-analyses; (9) a plausible biological rationale. Based on a review of the literature supporting these criteria, lutein is ready to be considered for intake recommendations. Establishing dietary guidance for lutein would encourage the consumption of lutein-containing foods and raise public awareness about its potential health benefits.

Diabetic brain or retina? Visual psychophysical performance in diabetic patients in relation to GABA levels in occipital cortex.

Visual impairment is one of the most feared complications of Type 2 Diabetes Mellitus. Here, we aimed to investigate the role of occipital cortex γ-aminobutyric acid (GABA) as a predictor of visual performance in type 2 diabetes. 18 type 2 diabetes patients were included in a longitudinal prospective one-year study, as well as 22 healthy age-matched controls. We collected demographic data, HbA1C and used a novel set of visual psychophysical tests addressing color, achromatic luminance and speed discrimination in both groups. Psychophysical tests underwent dimension reduction with principle component analysis into three synthetic variables: speed, achromatic luminance and color discrimination. A MEGA-PRESS magnetic resonance brain spectroscopy sequence was used to measure occipital GABA levels in the type 2 diabetes group. Retinopathy grading and retinal microaneurysms counting were performed in the type 2 diabetes group for single-armed correlations. Speed discrimination thresholds were significantly higher in the type 2 diabetes group in both visits; mean difference (95% confidence interval), [0.86 (0.32-1.40) in the first visit, 0.74 (0.04-1.44) in the second visit]. GABA from the occipital cortex predicted speed and achromatic luminance discrimination thresholds within the same visit (r = 0.54 and 0.52; p = 0.02 and 0.03, respectively) in type 2 diabetes group. GABA from the occipital cortex also predicted speed discrimination thresholds one year later (r = 0.52; p = 0.03) in the type 2 diabetes group. Our results suggest that speed discrimination is impaired in type 2 diabetes and that occipital cortical GABA is a novel predictor of visual psychophysical performance independently from retinopathy grade, metabolic control or disease duration in the early stages of the disease.

The effect of blue-light blocking spectacle lenses on visual performance, macular health and the sleep-wake cycle: a systematic review of the literature.

PURPOSE: Blue-blocking (BB) spectacle lenses, which attenuate short-wavelength light, are being marketed to alleviate eyestrain and discomfort when using digital devices, improve sleep quality and potentially confer protection from retinal phototoxicity. The aim of this review was to investigate the relative benefits and potential harms of these lenses. METHODS: We included randomised controlled trials (RCTs), recruiting adults from the general population, which investigated the effect of BB spectacle lenses on visual performance, symptoms of eyestrain or eye fatigue, changes to macular integrity and subjective sleep quality. We searched MEDLINE, EMBASE, the Cochrane Library and clinical trial registers, until 30 April 2017. Risk of bias was assessed using the Cochrane tool. RESULTS: Three studies (with 136 participants) met our inclusion criteria; these had limitations in study design and/or implementation. One study compared the effect of BB lenses with clear lenses on contrast sensitivity (CS) and colour vision (CV) using a pseudo-RCT crossover design; there was no observed difference between lens types (log CS; Mean Difference (MD) = -0.01 [-0.03, 0.01], CV total error score on 100-hue; MD = 1.30 [-7.84, 10.44]). Another study measured critical fusion frequency (CFF), as a proxy for eye fatigue, on wearers of low and high BB lenses, pre- and post- a two-hour computer task. There was no observed difference between low BB and standard lens groups, but there was a less negative change in CFF between the high and low BB groups (MD = 1.81 [0.57, 3.05]). Both studies compared eyestrain symptoms with Likert scales. There was no evidence of inter-group differences for either low BB (MD = 0.00 [-0.22, 0.22]) or high BB lenses (MD = -0.05 [-0.31, 0.21]), nor evidence of a difference in the proportion of participants showing an improvement in symptoms of eyestrain or eye fatigue. One study reported a small improvement in sleep quality in people with self-reported insomnia after wearing high compared to low-BB lenses (MD = 0.80 [0.17, 1.43]) using a 10-point Likert scale. A study involving normal participants found no observed difference in sleep quality. We found no studies investigating effects on macular structure or function. CONCLUSIONS: We find a lack of high quality evidence to support using BB spectacle lenses for the general population to improve visual performance or sleep quality, alleviate eye fatigue or conserve macular health.

Performance of real-world functional vision tasks by blind subjects improves after implantation with the Argus® II retinal prosthesis system.

BACKGROUND: The main objective of this study was to test Argus II subjects on three real-world functional vision tasks. DESIGN: The study was designed to be randomized and prospective. Testing was conducted in a hospital/research laboratory setting at the various participating centres. PARTICIPANTS: Twenty eight Argus II subjects, all profoundly blind, participated in this study. METHODS: Subjects were tested on the three real-world functional vision tasks: Sock Sorting, Sidewalk Tracking and Walking Direction Discrimination task MAIN OUTCOME MEASURES: For the Sock Sorting task, percentage correct was computed based on how accurately subjects sorted the piles on a cloth-covered table and on a bare table. In the Sidewalk Tracking task, an 'out of bounds' count was recorded, signifying how often the subject veered away from the test course. During the Walking Direction Discrimination task, subjects were tested on the number of times they correctly identified the direction of testers walking across their field of view. RESULTS: The mean percentage correct OFF versus ON for the Sock Sorting task was found to be significantly different for both testing conditions (t-test, P < 0.01). On the Sidewalk Tracking task, subjects performed significantly better with the system ON than they did with the system OFF (t-test, P < 0.05). Eighteen (18) of 27 subjects (67%) performed above chance with the system ON, and 6 (22%) did so with system OFF on the Walking Direction Discrimination task. CONCLUSIONS: Argus II subjects performed better on all three tasks with their systems ON than they did with their systems OFF.