New Visual Acuity Charts for Clinical Research
Three new visual acuity charts facilitate quantitative use of visual acuity test results. The charts have high-contrast lettering on washable white polystyrene. Each line has five Sloan letters; the lines are of equal difficulty, and there is a geometric progression in letter size from line to line. This provides a similar task for each line on the chart with the letter size being the only variable. Charts with different letter sequences are used for testing right and left eyes.
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Cited by (1837)
Red and green defocus curves and duochrome test in different age groups
2024, Journal of OptometryTo compare the eye defocus curves (DCs) obtained with stimuli on red, green, and white backgrounds and to investigate the applicability of the duochrome test (DT) in different age groups.
12 elderly (ELD: 59.3 ± 3.9 years) and 8 young (YG: 22.1 ± 1.1 years) subjects were recruited. An optometric assessment with the DT was carried out to obtain the subjective refraction at distance. DCs at distance on green, white, and red backgrounds were measured and the following parameters were deduced: dioptric difference between red-green, green-white, red-white focal positions (minima of the DCs), best corrected visual acuity (BCVA), and widths of the DCs for red, green, and white.
The DC difference between the green-white focal positions (mean ± standard deviation) was -0.12±0.17 diopters (D) (ELD, p = 0.012) and -0.11±0.12 D (YG, p = 0.039), while the red-white difference was not statistically significant. The DC red-green difference was 0.20±0.16 D (ELD, p = 0.002) and 0.18±0.18 D (YG, p = 0.008). The ELD BCVA with green background was significantly worse than BCVA with red (p = 0.007) and white (p = 0.007). The mean value of the DC's width in ELD for green (1.01±0.36 D) was higher than for red (0.77±0.21 D) and for white (0.84±0.35 D), but with no statistical significance.
Both age groups showed a slight focusing preference for red when using white light. Moreover, ELD showed a worse BCVA with a green compared to a red background. Despite these results deduced by DC analyses, these aspects do not compromise the possibility of using the DT in clinical practice both in the young and in the elderly. Furthermore, the difference of about 0.20 D between red-green DC in both groups confirms the clinical appropriateness of the widespread use of 0.25 D step as the standard minimum difference in power between correcting lenses.
Evaluation of a Retinal Projection Laser Eyeware in Patients with Visual Impairment Caused by Corneal Diseases in a Randomized Trial
2024, OphthalmologyPatients with incurable corneal diseases experience visual impairment (VI) despite having a healthy retina and optic pathway. Low-vision aids (LVAs) can optimize the use of remaining vision through magnification and contrast enhancement, but do not harness the full visual capacity because they rely on the optic media. Therefore, we investigated a novel laser eyewear (LEW) technology that bypasses the anterior segment of the eye. Images captured by an integrated camera are projected directly onto the retina using a low-energy laser. The patient is able to view a full-color video, realized as augmented reality. We aimed to evaluate the efficacy of the LEW to enhance the vision of individuals with corneal diseases.
Prospective, randomized, crossover clinical trial.
We examined the retinal projection glasses in 21 patients (25–69 years) with VI (0.7 logarithm of the minimum angle of resolution [logMAR] or worse) resulting from corneal diseases. Patients with comorbidities that impact vision, such as retinal disorders, were excluded.
Standardized measurements of visual acuity (VA) for near vision (NV) and distance vision (DV) were conducted using ETDRS charts with the respective best correction (BC) and then with LEW. In addition reading speed, vision-related quality of life (QoL) and capacity to carry out daily tasks were assessed at an initial visit and at 2 subsequent visits after a home phase with and without the device. Six weeks after last use of the LEW, an ophthalmologic examination including spectral-domain-OCT or full-field-electroretinography was conducted and compared with baseline findings to evaluate the safety of the device. Four patients participated and completed a subsequent 12-month follow-up phase.
Improvement of VA using the LEW. Secondary objectives included safety, reading speed, QoL, and usability in daily activities.
The mean VA in patients with VI was improved by 0.43 logMAR in DV using the LEW compared with BC (P < 0.0001). Using the ×2 magnification mode of the LEW resulted in an average improvement of 0.66 logMAR compared with BC (P < 0.0001). In NV, an increase of 0.47 logMAR was achieved compared with BC (P < 0.0001). Although only 4 of 21 participants were able to read with BC, 17 of 21 participants were able to read with the LEW. Quality of life significantly improved in the 17 participants who completed all visits.
We demonstrated that the retinal projection glasses resulted in enhanced VA for all participants by directly projecting images onto the intact retina. In future, the LEW could represent a new option as an LVA for patients with corneal diseases. No pathological alterations were observed in the safety assessments.
The author(s) have no proprietary or commercial interest in any materials discussed in this article.
BCLA CLEAR Presbyopia: Definitions
2024, Contact Lens and Anterior EyePresbyopia is often the first sign of ageing experienced by humans. Standardising terminology and adopting it across the BCLA CLEAR Presbyopia reports, improves consistency in the communication of the evidence-based understanding of this universal physiological process. Presbyopia can be functionally and psychologically debilitating, especially for those with poor access to eyecare. Presbyopia was defined as occurring when the physiologically normal age-related reduction in the eye’s focusing range reaches a point that, when optimally corrected for far vision, the clarity of vision at near is insufficient to satisfy an individual’s requirements. Accommodation is the change in optical power of the eye due to a change in crystalline lens shape and position, whereas pseudo-accommodation is the attainment of functional near vision in an emmetropic or far-corrected eye without changing the refractive power of the eye. Other definitions specific to vision and lenses for presbyopia were also defined. It is recommended that these definitions be consistently adopted in order to standardise future research, clinical evaluations and education.
Cortical dynamics in visual areas induced by the first use of multifocal contact lenses in presbyopes
2024, Contact Lens and Anterior EyeA common non-spectacle strategy to correct presbyopia is to provide simultaneous images with multifocal optical designs. Understanding the neuroadaptation mechanisms behind multifocal devices usage would have important clinical implications, such as predicting whether patients will be able to tolerate multifocal optics. The aim of this study was to evaluate the brain correlates during the initial wear of multifocal contact lenses (CLs) using high-density visual evoked potential (VEP) measures. Fifteen presbyopes (mean age 51.8 ± 2.6 years) who had previously not used multifocal CLs were enrolled. VEP measures were achieved while participants looked at arrays of 0.5 logMAR Sloan letters in three different optical conditions arranged with CLs: monofocal condition with the optical power appropriate for the distance viewing; multifocal correction with medium addition; and multifocal correction with low addition. An ANOVA for repeated measures showed that the amplitude of the C1 and N1 components significantly dropped with both multifocal low and medium addition CL conditions compared to monofocal CLs. The P1 and P2 components showed opposite behavior with an increase in amplitudes for multifocal compared to monofocal conditions. VEP data indicated that multifocal presbyopia corrections produce a loss of feedforward activity in the primary visual cortex that is compensated by extra feedback activity in extrastriate areas only, in both early and late visual processing.
Reliability of self-measurement of visual acuity in AMD patients with two electronic devices based on the ETDRS chart: A randomized study
2024, Journal Francais d'OphtalmologieAge-related macular degeneration (AMD) requires continuous visual acuity (VA) monitoring, increasing the burden on the health care system. Self-measurement VA tests are available on various devices. However, none of them have been based on an internationally validated benchmark chart, such as that of the Early Treatment Diabetic Retinopathy Study (ETDRS). The goal of this study was to assess the reliability of two digitized ETDRS charts adapted to two electronic devices for self-measurement of VA.
A prospective, single-center, 1:1 randomized, two-arm, parallel group trial was conducted. The main objective was to compare VA variation as conventionally measured on a 4-m ETDRS chart versus self-measured with digitized ETDRS charts in patients treated for AMD. At each visit, conventional measurement and patient self-measurement, either on a computer at 80-cm (arm 1) or on a tablet at 40-cm (arm 2), were performed.
Eighty patients were included (25 men, 55 women, mean age 81.3 ± 7.4 years). No significant differences were observed between VA variation, conventionally measured and self-measured on a computer (arm 1; P = 0.914) or tablet (arm 2; P = 0.913).
These results confirm the reliability of these two methods for self-measurement of VA, and will lead to the development of a wider “telemedicine” project extended to self-measurement of VA in various pathologies.
La dégénérescence maculaire liée à l’âge (DMLA) nécessite un contrôle continu de l’acuité visuelle (AV), ce qui augmente la charge des hôpitaux. Des tests d’autoévaluation de l’AV sont disponibles sur différents appareils. Cependant, aucun n’était basé sur une échelle de référence validée au niveau international comme l’Early Treatment Diabetic Retinopathy Study (ETDRS). Le but de cette étude était d’évaluer la fiabilité de deux cartes ETDRS numérisées adaptées sur deux appareils électroniques, pour l’automesure de l’AV.
Un essai prospectif, monocentrique, randomisé 1/1 à deux bras parallèles, a été mené. L’objectif principal était de comparer la variation de l’AV conventionnellement mesurée à 4 m par rapport à l’automesure sur des cartes ETDRS mesurées chez les patients traités pour une DMLA. À chaque visite, les mesures d’AV suivantes ont été réalisées : mesure conventionnelle et automesure, soit sur un ordinateur à 80 cm (bras 1), soit sur une tablette à 40 cm (bras 2).
Quatre-vingt patients ont été inclus (25 hommes, 55 femmes, âge moyen 81,3 ± 7,4 ans). Aucune différence significative n’a été observée entre la variation de l’AV mesurée avec la méthode conventionnelle et l’automesure sur un ordinateur à 80 cm (bras 1, p = 0,914) ou une tablette à 40 cm (bras 2, p = 0,913).
Ces résultats confirment la fiabilité des deux méthodes d’autoévaluation de l’AV et permettront de développer un projet plus large de « télémédecine », étendu à l’autoévaluation de l’AV dans diverses pathologies.
Durable vision improvement after a single intravitreal treatment with antisense oligonucleotide in CEP290-LCA: Replication in two eyes
2023, American Journal of Ophthalmology Case ReportsAn intravitreally injected antisense oligonucleotide, sepofarsen, was designed to modulate splicing within retinas of patients with severe vision loss due to deep intronic c.2991 + 1655A > G variant in the CEP290 gene. A previous report showed vision improvements following a single injection in one eye with unexpected durability lasting at least 15 months. The current study evaluated durability of efficacy beyond 15 months in the previously treated left eye. In addition, peak efficacy and durability were evaluated in the treatment-naive right eye, and re-injection of the left eye 4 years after the first injection.
Visual function was evaluated with best corrected standard and low-luminance visual acuities, microperimetry, dark-adapted chromatic perimetry, and full-field sensitivity testing. Retinal structure was evaluated with OCT imaging. At the fovea, all visual function measures and IS/OS intensity of the OCT showed transient improvements peaking at 3–6 months, remaining better than baseline at ∼2 years, and returning to baseline by 3–4 years after each single injection.
These results suggest that sepofarsen reinjection intervals may need to be longer than 2 years.
Reprint requests to Frederick L. Ferris III, M.D., Office of Biometry and Epidemiology, National Eye Institute, Building 31, Room 6A24, Bethesda, MD 20205.