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\"Near and far are important concepts to understand--who doesn't want to know if a shark is near or far? This colorful volume is an enjoyable exploration of this pair of opposites. It invites beginning readers to practice using these terms in relation to familiar and fun scenarios in the real world. They'll spot near and faraway elephants, sharks, birds, and boats in the lively photographs accompanying the achievable text.\"-- Provided by publisher.
Book
Randomised clinical trial of extended depth of focus lenses for controlling myopia progression: Outcomes from SEED LVPEI Indian Myopia Study
PurposeTo determine the efficacy of extended depth of focus (EDOF) contact lenses for controlling myopia progression in children through a 1-year randomised clinical trial.MethodsA total of 104 children aged 7–15 years, with spherical equivalent refraction ≤−0.50 D, were randomly assigned to wear SEED 1 dayPure EDOF Mid contact lenses (n=48) or single vision spectacle lenses (n=56). Cycloplegic refraction with Shin-Nippon open field autorefractor and axial length with Lenstar LS 900 was determined at the baseline and 12-month visits. The compliance, visual discomfort and dryness questionnaires were administered during the final visit.ResultsSixty-nine children (control: n=38; treatment: 31) completed the 12-month follow-up visit, with no difference in baseline characteristics between the groups. Mean (SEM) myopia progression in the 12th month was −0.48±0.07D in the control group and −0.20±0.08D in the treatment group. Mean axial elongation was 0.22±0.03 mm and 0.11±0.03 mm in the control and treatment groups, respectively. SEED 1 dayPure EDOF Mid contact lenses slowed myopia progression by 59% (−0.28D; p=0.01) based on spherical equivalent refraction and controlled axial length by 49% (0.11 mm; p=0.007) in comparison to single vision spectacle lenses. None of the participants reported any adverse effects. While most of the participants (82%) were comfortable with the contact lenses, 11% reported occasional dryness and 14% experienced mild fluctuations in visual acuity after immediate lens wear.ConclusionDaily wear of SEED 1 dayPure EDOF Mid contact lenses in Indian children showed a significant effect in controlling myopia progression and axial elongation.
Journal Article
Measuring egocentric distance perception in virtual reality: Influence of methodologies, locomotion and translation gains
Virtual reality has become a popular means to study human behavior in a wide range of settings, including the role of pedestrians in traffic research. To understand distance perception in virtual environments is thereby crucial to the interpretation of results, as reactions to complex and dynamic traffic scenarios depend on perceptual processes allowing for the correct anticipation of future events. A number of approaches have been suggested to quantify perceived distances. While previous studies imply that the selected method influences the estimates' accuracy, it is unclear how the respective estimates depend on depth information provided by different perceptual modalities. In the present study, six methodological approaches were compared in a virtual city scenery. The respective influence of visual and non-visual cues was investigated by manipulating the ratio between visually perceived and physically walked distances. In a repeated measures design with 30 participants, significant differences between methods were observed, with the smallest error occurring for visually guided walking and verbal estimates. A linear relation emerged between the visual-to-physical ratio and the extent of underestimation, indicating that non-visual cues during walking affected distance estimates. This relationship was mainly evident for methods building on actual or imagined walking movements and verbal estimates.
Journal Article
Quality of vision clinical outcomes for a new fully-refractive extended depth of focus Intraocular Lens
Background/objective
To evaluate the visual performance of a purely refractive extended depth of focus (EDF) intraocular lens (IOL).
Subjects/methods
A prospective, multi-center, randomized, subject/evaluator-masked study. Subjects were bilaterally implanted with the EDF test (Model ZEN00V, TECNIS PureSee™ IOL,
N
= 60) or an enhanced monofocal control (Model ICB00, TECNIS Eyhance™ IOL,
N
= 57) IOL. Monocular corrected distance (CDVA), intermediate (DCIVA), near acuities (DCNVA) and patient reported visual symptoms were evaluated at the 6-month visit. Monocular mesopic contrast sensitivity (CS) and depth of focus (DOF) testing were assessed at 3 months.
Results
CDVA (Mean ± SD) was −0.06 ± 0.08 for test and −0.05 ± 0.08 logMAR for control groups. DCIVA was 0.13 ± 0.08 for test and 0.18 ± 0.14 logMAR for control groups (
p
= 0.0127). DCNVA was 0.37 ± 0.10 for test and 0.43 ± 0.16 logMAR for control groups (
p
= 0.0137). Test lens was statistically superior for intermediate and near. Overall, 91.7% (halos), 95.0% (starbursts) and 95.0% (glare) of test lens patients reported that they did not experience, were not bothered, or were slightly bothered by specific visual symptoms, compared to 98.2%, 100% and 96.5% in the control group. The DOF range over which monocular visual acuity was 0.20 logMAR or better was −1.6 D for the test lens. Mesopic CS was comparable between both groups, falling within 0.11 log units for all measured cycles per degree with and without glare.
Conclusion
The EDF IOL demonstrated extended range of vision and statistically superior intermediate and near performance compared to the monofocal IOL. Distance visual acuity, contrast sensitivity and dysphotopsia profile were similar to the monofocal IOL.
Journal Article
Comparison of clinical outcomes between different combinations of hybrid multifocal, extended-depth-of-focus and enhanced monofocal intraocular lenses
PurposeTo compare clinical outcomes of bilateral implantation of hybrid multifocal intraocular lenses (IOLs) versus mix-and-match implantation of hybrid multifocal and extended-depth-of-focus (EDOF) versus mix-and-match implantation of hybrid multifocal and enhanced monofocal IOLs.MethodsPatients with bilateral age-related cataract were randomised in one of three groups: group 1, bilateral hybrid multifocal IOL; group 2, EDOF in the dominant eye, hybrid multifocal in the non-dominant eye; group 3, enhanced monofocal in the dominant eye, hybrid multifocal in the non-dominant eye. Assessments at 6 months postoperatively included monocular and binocular uncorrected distance visual acuity (UDVA), intermediate (UIVA) and near distance (UNVA) at 40 and 33 cm, defocus curves, contrast sensitivity (CS), reading speed and questionnaires on quality of vision and dysphotopsia.Results75 patients (25 per group) were enrolled. There were no statistically significant differences in binocular UDVA and UNVA between groups (p>0.05); binocular UIVA was better for group 1 and 2 versus group 3 (p=0.030). Binocular uncorrected defocus curve showed better performance for group 1 compared with group 3 from −2.00 to −3.50 D. Significantly higher reading speed was measured for Jaeger 1 font in group 1. There were no differences in CS between groups, but higher incidence of starbursts in group 1 and higher need for near spectacles in group 3.ConclusionBilateral hybrid multifocal IOL implantation resulted in better near vision, but higher rates of photic phenomena compared with the mix-and-match groups. Combinations of IOLs may allow surgeons to fine-tune for individual patient’s needs.
Journal Article
Stereoscopic depth perception through foliage
Both humans and computational methods struggle to discriminate the depths of objects hidden beneath foliage. However, such discrimination becomes feasible when we combine computational optical synthetic aperture sensing with the human ability to fuse stereoscopic images. For object identification tasks, as required in search and rescue, wildlife observation, surveillance, and early wildfire detection, depth assists in differentiating true from false findings, such as people, animals, or vehicles vs. sun-heated patches at the ground level or in the tree crowns, or ground fires vs. tree trunks. We used video captured by a drone above dense woodland to test users’ ability to discriminate depth. We found that this is impossible when viewing monoscopic video and relying on motion parallax. The same was true with stereoscopic video because of the occlusions caused by foliage. However, when synthetic aperture sensing was used to reduce occlusions and disparity-scaled stereoscopic video was presented, whereas computational (stereoscopic matching) methods were unsuccessful, human observers successfully discriminated depth. This shows the potential of systems which exploit the synergy between computational methods and human vision to perform tasks that neither can perform alone.
Journal Article
Perception of distance during self-motion depends on the brain’s internal model of the terrain
The body’s geometrical relationship with the terrain is important for depth perception of human and non-human terrestrial animals. Static human observers in the dark employ the brain’s internal model of the terrain, the intrinsic bias, to represent the ground as an allocentric reference frame for coding distance. However, it is unknown if the same ground-based coding process operates when observers walk in a cue-impoverished environment with visible ground surface. We explored this by measuring human observers’ perceived locations of dimly-lit targets after a short walk in the dark from the home-base location. We found the intrinsic bias was kept at the home-base location and not the destination-location after walking, causing distance underestimation, fitting its allocentric nature. We then measured perceived distance of dimly-lit targets from the destination-location when there were visual depth cues on the floor. We found judged locations of targets on the floor transcribed a slanted surface shifted towards the home-base location, indicating distance underestimation. This suggests, in dynamically translating observers, the brain integrates the allocentric intrinsic bias with visual depth cues to construct an allocentric ground reference frame. More broadly, our findings underscore the dynamic interaction between the internal model of the ground and external depth cues.
Journal Article
Tolerance to refractive error with a new extended depth of focus intraocular lens
Purpose
To evaluate the tolerance to refractive errors of a new purely refractive extended depth of focus (EDF) intraocular lens (IOL), TECNIS PureSee™ IOL, using preclinical and clinical metrics.
Methods
Preclinical evaluation included computer simulations of visual acuity (sVA) and dysphotopsia profile of different IOL designs (refractive EDF, diffractive EDF, multifocal, standard, and enhanced monofocals) using an appropriate eye model with and without ±0.50 D defocus and/or +0.75 D of astigmatism. Patients bilaterally implanted with a refractive EDF (Model ZEN00V, TECNIS PureSee™ IOL) or an enhanced monofocal (Model ICB00, TECNIS Eyhance™ IOL) IOL from a prospective, randomized study were included. At the 6-month postoperative visit, uncorrected and corrected distance vision (UDVA and CDVA), visual symptoms, satisfaction and dependency on glasses were evaluated in a subgroup of patients with absolute residual refractive error of >0.25 D in one or both eyes.
Results
In the presence of defocus and astigmatism, sVA was comparable for all except the multifocal IOL design. The refractive EDF was more tolerant to myopic outcomes and maintained a monofocal-like dysphotopsia profile with defocus. Binocular logMAR UDVA was −0.03 ± 0.08 for ZEN00V and −0.02 ± 0.11 for ICB00. 100% ZEN00V and 97% ICB00 patients did not need glasses and were satisfied with their distance vision. Monocular CDVA, contrast sensitivity and visual symptoms were also similar between both groups.
Conclusions
The clinical outcomes of the refractive EDF IOL demonstrated high quality distance vision and dysphotopsia comparable to a monofocal IOL, even in the presence of refractive error, thus matching the design expectations of the EDF IOL.
Journal Article
Characterization of depth perception information inferred from neuronal activity in primary visual cortex
Depth perception is crucial for spatial awareness, enabling animals to interpret three-dimensional environments. Although the primary visual cortex (V1) is known to process depth information, the specific contributions of V1 neurons to various aspects of depth perception remain underexplored. In this study, we investigated how V1 neurons engage in both passive and active depth-related tasks, examining whether distinct neuronal populations support different aspects of depth processing. Using in vivo calcium imaging in freely moving mice, we observed that specific groups of V1 neurons are selectively active in passive (visual cliff) and active (depth discrimination) tasks, suggesting functional segregation within V1. Additionally, neurons in the primary visual cortex prefer encoding objective positions rather than egocentric distances in non-depth-based tasks. Moreover, egocentric distance discrimination, as reflected by the primary visual cortex, appears to be more prospective. These findings provide insight into V1’s versatility, highlighting its potential role in spatial navigation and decision-making.
Journal Article