Distance stereopsis in patients with accommodative esotropia.

PURPOSE: We aimed to evaluate distance stereoacuity (DS) in patients with successfully treated accommodative esotropia (AET) and its association with other clinical factors. METHODS: The medical records of 176 children with refractive AET with a follow-up period ≥ 1 year were reviewed to identify a cohort of patients who achieved a stable alignment within 4 prism diopters (PD) of orthotropia at both distance and near fixation. Age of onset, duration of misalignment, uncorrected near and distance deviation, accommodative convergence/accommodation ratio, refractive error, presence of anisometropia and amblyopia, near stereopsis were evaluated as predictors of outcome. DS was measured using the Distance Randot Stereo test and near stereoacuity by Randot Stereotest. The patient group was compared with 50 age-matched normal controls for DS. RESULTS: Fifty-six patients were included, and 38 patients had DS at the final visit. All patients with DS attained uncontoured near stereopsis (UCNS). UCNS was present only in 11 patients without DS (p = 0.001). Anisometropia (p = 0.997), uncorrected near deviation (p = 0.224), distance deviation with correction (p = 0.255), and high hypermetropia (p = 0.998) were not associated with DS. The multivariable regression model showed a significant positive correlation between UCNS and DS (OR = 31.14 (95% CI 2.25-430.48); p = 0.01). Contoured near stereopsis outcome was significantly different between the patients with and without DS (p = 0.001 for animals and p = 0.003 for circles). Compared with the control group, the patient group yielded lower DS scores (p = 0.001). CONCLUSION: Distance Randot Stereotest can be useful in measuring binocular vision recovery after successful realignment in refractive AET patients. Patients attaining normal scores for near stereopsis tests after optical correction revealed subnormal thresholds for DS.

Combination of a monofocal and one type of extended depth-of-focus (zonal refractive) intraocular lens (COMEDI) in bilateral cataract surgery protocol: a monocentric, randomised, parallel group trial in cataract surgery.

INTRODUCTION: Modern intraocular lens (IOL) designs for cataract treatment can be broadly classified into three focal range categories; monofocal, extended depth-of-focus (EDOF) and multifocal IOLs.Monofocal IOLs allow spectacle independence for one focus, typically distance. In contrast, EDOF IOLs provide a greater range of vision, extending spectacle independence to intermediate distance, while multifocal IOLs enable spectacle independence at all distances with the drawback of positive dysphotopsias and reduced contrast perception.EDOF lenses are an attractive compromise with fewer dysphotopic side effects than multifocals. The purpose of this study is to assess whether implanting an EDOF IOL in the second eye of a patient who received a monofocal IOL in the first eye can improve spectacle independence while maintaining the same optical quality as bilateral monofocal IOL implantation. METHODS AND ANALYSIS: This study compares combined monofocal and EDOF IOL implantation versus bilateral monofocal IOL implantation in terms of clinical and patient-reported outcomes in a monocentric, randomised, patient-masked and assessor-masked, parallel group trial in 88 bilateral cataract patients. The primary outcome measure is binocular photopic distance corrected intermediate visual acuity. The secondary outcome measures include (un)corrected distance and near visual acuity, reading speed at intermediate distance, quality of visual function assessments, patient-reported spectacle independence, contrast sensitivity, aberrometry, stereopsis and straylight measurement at the 3-month follow-up. ETHICS AND DISSEMINATION: The protocol was approved by the ethical committee of the University Hospital of Brussels (BUN 23219_EDOF). TRIAL REGISTRATION NUMBER: NCT06002399.

Functional Design Analysis of Two Current Extended-Depth-of-Focus Intraocular Lenses.

Purpose: To evaluate the differences between two extended depth-of-focus intraocular lenses, the Alcon IQ Vivity and the Bausch & Lomb LuxSmart and to compare them with a simple monofocal lens, the Alcon IQ, using a simulation-based approach. Methods: A mathematical lens model was created for each lens type based on a measured surface geometry. The lens model was then used in a raytracer to calculate a refractive power map of the lens and a ray propagation image for the focal zone. Results: The simulations confirm the enhanced depth of focus of these two lenses. There are apparent differences between the models. For the Vivity, more light is directed into the far focus in low light conditions, whereas the LuxSmart behaves more pupil independent and prioritizes intermediate vision. Conclusions: The simulation-based approach was effective in evaluating and comparing the design aspects of these lenses. It can be positioned as a valuable third tool for lens characterization, complementing in vivo studies and in vitro measurements. Translational Relevance: With this approach not only focusing on the resulting optical performance, but the underlying functional mechanisms, it paves the way forward for a better adaptation to the individual needs and preferences of patients.

Viewpoint adaptation revealed potential representational differences between 2D images and 3D objects.

For convenience and experimental control, cognitive science has relied largely on images as stimuli rather than the real, tangible objects encountered in the real world. Recent evidence suggests that the cognitive processing of images may differ from real objects, especially in the processing of spatial locations and actions, thought to be mediated by the dorsal visual stream. Perceptual and semantic processing in the ventral visual stream, however, has been assumed to be largely unaffected by the realism of objects. Several studies have found that one key difference accounting for differences between real objects and images is actability; however, less research has investigated another potential difference - the three-dimensional nature of real objects as conveyed by cues like binocular disparity. To investigate the extent to which perception is affected by the realism of a stimulus, we compared viewpoint adaptation when stimuli (a face or a kettle) were 2D (flat images without binocular disparity) vs. 3D (i.e., real, tangible objects or stereoscopic images with binocular disparity). For both faces and kettles, adaptation to 3D stimuli induced stronger viewpoint aftereffects than adaptation to 2D images when the adapting orientation was rightward. A computational model suggested that the difference in aftereffects could be explained by broader viewpoint tuning for 3D compared to 2D stimuli. Overall, our finding narrowed the gap between understanding the neural processing of visual images and real-world objects by suggesting that compared to 2D images, real and simulated 3D objects evoke more broadly tuned neural representations, which may result in stronger viewpoint invariance.

Visual and clinical outcomes after bilateral implantation of a novel extended depth of focus lens post cataract surgery.

PURPOSE: To assess the visual and clinical outcomes after bilateral implantation of the novel extended depth of focus (EDOF) (AcrySof IQ Vivity) intraocular lens (IOL) using a micromonovision strategy. METHODS: This was a prospective interventional study at a tertiary care center. Twenty patients (40 eyes) underwent bilateral implantation of AcrySof IQ Vivity IOL. Twelve weeks postoperatively, both uncorrected vision and corrected vision were assessed. Uniocular and binocular defocus curves with and without correction were noted subjectively as well as objectively on I-trace. Contrast sensitivity was assessed with a FACT (Functional Acuity Contrast Testing) machine, and objective parameters like modulation transfer function and Strehl ratio were also measured on I-Trace. Subjective quality of vision using a subjective questionnaire was also evaluated. RESULTS: The mean binocular postoperative uncorrected distance visual acuity in LogMAR was -0.03 ± 0.09, the uncorrected intermediate visual acuity was 0.03 ± 0.09, and the uncorrected near visual acuity was 0.28 ± 0.18. All defocus curves were smooth and broad with the uncorrected defocus curve (with the micromonovision strategy) better than the corrected defocus curve. The subjective depth of focus (DOF = 3.73) was more than objective DOF (1.93) (P < 0.05). Photopic contrast was better than mesopic at all frequencies. All aberrations increased at 5 mm pupil size compared to 3 mm pupil size and were statistically significant, except for the total eye spherical aberration, which shows no significant difference at 3 mm and 5 mm pupil size (P = 0.27). Spectacle independence for distance, intermediate, and near was achieved in 100%, 94.7%, and 94.7% cases in this study, respectively. CONCLUSIONS: Using the micromonovision strategy, the visual performance of this novel EDOF IOL was outstanding both subjectively and objectively.

Clinical outcomes and optical performance of a new segmental refractive extended depth-of-focus intraocular lens.

BACKGROUND: The visual performance and the optical quality of a segmental refractive extended depth-of-focus (EDoF) intraocular lens (IOL) were evaluated in a prospective, single-arm, single-center study. METHODS: A total of 20 patients (40 eyes) after bilateral implantation of the refractive segmental EDoF Acunex Vario AN6V were included. Assessment procedure: refraction outcome, monocular and binocular uncorrected (UCVA) and distance-corrected visual acuity (DCVA), defocus curve, contrast sensitivity (CS), higher-order aberrations (HOAs) and patient satisfaction were evaluated 1 and 3 months after surgery. RESULTS: At 3-month follow-up, mean spherical equivalent was - 0.23 ± 0.32 D. Binocular uncorrected distance visual acuity (VA) at distance, intermediate and near was - 0.08 ± 0.06 logMAR at 4 m, -0.03 ± 0.06 logMAR at 66 cm and 0.16 ± 0.06 logMAR at 40 cm, respectively. The binocular defocus curve showed a VA better than 0.20 logMAR over a range from + 1.50 to - 2.45 D. Contrast sensitivity aligned with monofocal lenses, highlighting the lens's clinical value. Aberrometry showed minimal changes in corneal aberrations. NEI-RQL-42-Questionnaire showed a high patient satisfaction for daily activities and revealed reduced dependence on glasses, particularly for near and intermediate vision. The Acunex Vario AN6V demonstrated minimal dysphotopsias, making it a promising option for those seeking spectacle independence. CONCLUSION: This segmental refractive EDoF IOL provides a high degree of spectacle independence for far and intermediate distances with functional near VA. Although inducing residual coma aberrations, it showed subjectively good results with little dysphotopsias. TRIAL REGISTRATION: This study protocol was reviewed and approved by ethics committee of Charité University, Berlin, Germany, with approval number EA4/126/20.

Postoperative Visual Function of Extended Depth-of-Focus Intraocular Lenses Versus Monofocal Lenses.

PURPOSE: To assess the effects of intraocular lens (IOL) decentration and tilt, as well as age, on postoperative visual function (corrected distance visual acuity [CDVA] and contrast sensitivity) by comparing an extended depth-of-focus IOL using higher order aspheric optics against a monofocal IOL from the same platform. METHODS: This retrospective observational study targeted patients without other eye diseases who underwent surgery to implant the Tecnis Eyhance OptiBlue or the monofocal IOL Tecnis OptiBlue 1-Piece (J&J Vision) during cataract surgery from November 2021 to December 2022. The effects of age, axial length, IOL decentration, tilt, and corneal higher order aberrations (HOAs) on the postoperative 5 m CDVA and area under log contrast sensitivity function (AULCSF) under photopic and scotopic conditions were evaluated within 3 months of surgery. RESULTS: No significant difference was found in postoperative CDVA between the Tecnis Eyhance OptiBlue group (n = 61 eyes) and the Tecnis OptiBlue 1-Piece group (n = 35 eyes), but AULCSF was significantly better in the Tecnis Eyhance OptiBlue group for photopic (1.58 ± 0.13 vs 1.46 ± 0.18; P = .002) and scotopic (1.71 ± 0.11 vs 1.59 ± 0.19; P = .002) eyes. Multivariate analysis showed a negative correlation between AULCSF and IOL decentration and age in the Tecnis Eyhance OptiBlue group (P < .01), with no significant correlation with tilt, axial length, and corneal HOAs. CONCLUSIONS: The Tecnis Eyhance OptiBlue yielded significantly better contrast sensitivity under photopic and scotopic conditions than the Tecnis OptiBlue 1-Piece. However, it is important to consider the effects of IOL decentration and age when evaluating the contrast sensitivity of the Tecnis Eyhance OptiBlue. [J Refract Surg. 2024;40(7):e499-e505.].

Trifocal versus extended depth of focus (EDOF) intraocular lenses after cataract extraction.

BACKGROUND: Cataract, defined as an opacity of the lens in one or both eyes, is the leading cause of blindness worldwide. Cataract may initially be treated with new spectacles, but often surgery is required, which involves removing the cataract and placing a new artificial lens, usually made from hydrophobic acrylic. Recent advancements in intraocular lens (IOL) technology have led to the emergence of a diverse array of implantable lenses that aim to minimise spectacle dependence at all distances (near, intermediate, and distance). To assess the relative merits of these lenses, measurements of visual acuity are needed. Visual acuity is a measurement of the sharpness of vision at a distance of 6 metres (or 20 feet). Normal vision is 6/6 (or 20/20). The Jaegar eye card is used to measure near visual acuity. J1 is the smallest text and J2 is considered equivalent to 6/6 (or 20/20) for near vision. OBJECTIVES: To compare visual outcomes after implantation of trifocal intraocular lenses (IOLs) to those of extended depth of focus (EDOF) IOLs. To produce a brief economic commentary summarising recent economic evaluations that compare trifocal IOLs with EDOF IOLs. SEARCH METHODS: We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register), MEDLINE, Embase, and three trial registries on 15 June 2022. For our economic evaluation, we also searched MEDLINE and Embase using economic search filters to 15 June 2022, and the NHS Economic Evaluation Database (EED) from 1968 up to and including 31 December 2014. We did not use any date or language restrictions in the electronic searches. SELECTION CRITERIA: We included studies comparing trifocal and EDOF IOLs in adults undergoing cataract surgery. We did not include studies involving people receiving IOLs for correction of refractive error alone (or refractive lens exchange in the absence of cataract). DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Two review authors working independently selected studies for inclusion and extracted data from the reports. We assessed the risk of bias in the studies, and we assessed the certainty of the evidence using the GRADE approach. MAIN RESULTS: We included five studies that compared trifocal and EDOF lenses in people undergoing cataract surgery. Three trifocal lenses (AcrySof IQ PanOptix, ATLISA Tri 839MP, FineVision Micro F) and one EDOF lens (TECNIS Symfony ZXR00) were evaluated. The studies took place in Europe and North America. Follow-up ranged from three to six months. Of the 239 enroled participants, 233 (466 eyes) completed follow-up and were included in the analyses. The mean age of participants was 68.2 years, and 64% of participants were female. In general, the risk of bias in the studies was unclear as methods for random sequence generation and allocation concealment were poorly reported, and we judged one study to be at high risk of performance and detection bias. We assessed the certainty of the evidence for all outcomes as low, downgrading for the risk of bias and for imprecision. In two studies involving a total of 254 people, there was little or no difference between trifocal and EDOF lenses for uncorrected and corrected distance visual acuity worse than 6/6. Sixty per cent of participants in both groups had uncorrected distance visual acuity worse than 6/6 (risk ratio (RR) 1.06, 95% confidence intervals (CI) 0.88 to 1.27). Thirty-one per cent of the trifocal group and 38% of the EDOF group had corrected distance visual acuity worse than 6/6 (RR 1.04, 95% CI 0.78 to 1.39). In one study of 60 people, there were fewer cases of uncorrected near visual acuity worse than J2 in the trifocal group (3%) compared with the EDOF group (30%) (RR 0.08, 95% CI 0.01 to 0.65). In two studies, participants were asked about spectacle independence using subjective questionnaires. There was no evidence of either lens type being superior. One further study of 60 participants reported, "overall, 90% of patients achieved spectacle independence", but did not categorise this by lens type. All studies included postoperative patient-reported visual function, which was measured using different questionnaires. Irrespective of the questionnaire used, both types of lenses scored well, and there was little evidence of any important differences between them. Two studies included patient-reported ocular aberrations (glare and halos). The outcomes were reported in different ways and could not be pooled; individually, these studies were too small to detect meaningful differences in glare and halos between groups. One study reported no surgical complications. Three studies did not mention surgical complications. One study reported YAG capsulotomy for posterior capsular opacification (PCO) in one participant (one eye) in each group. One study reported no PCO. Two studies did not report PCO. One study reported that three participants (one trifocal and two EDOF) underwent laser-assisted subepithelial keratectomy (LASEK) to correct residual myopic refractive error or astigmatism. One study reported a subset of participants who were considering laser enhancement at the end of the study period (nine trifocal and two EDOF). Two studies did not report laser enhancement rates. No economic evaluation studies were identified for inclusion in this review. AUTHORS' CONCLUSIONS: Distance visual acuity after cataract surgery may be similar whether the lenses implanted are trifocal IOLs or EDOF (TECNIS Symfony) IOLs. People receiving trifocal IOLs may achieve better near vision and may be less dependent on spectacles for near vision. Both lenses were reported to have adverse subjective visual phenomena, such as glare and halos, with no meaningful difference detected between lenses.

Pencil push-up training compared with binocular vision training in the management of slight post-operative under-correction of intermittent exotropia: A prospective study.

PURPOSE: This study aims to compare the effectiveness of pencil push-up training and binocular vision training in treating post-operative mild under-correction in patients with intermittent exotropia. METHODS: A prospective cohort study was conducted, including patients who underwent surgery for intermittent exotropia at Children's Hospital of Nanjing Medical University between June 2022 and January 2023 and experienced post-operative mild under-correction (-8∆ to -15∆). Patients were divided into two groups: pencil push-up training group and binocular vision training group. All patients underwent measurements of exodeviation and stereoacuity at distance and near, sensory fusion, and fusion convergence amplitude. The data were analyzed using independent sample t-tests, repeated measures analysis of variance, and Chi-square tests. RESULTS: There were no statistically significant differences in exodeviation at distance and near between the two training groups before the training. After 6 months of training, the exodeviation at distance and near achieved a significant decrease in both groups (P < 0.05), and the pencil push-up training group showed a similar distance and near exodeviation compared to the binocular vision training group (t = 1.58, P ＞ 0.05; t = 0.43, P ＞ 0.05). After 6 months of training, the binocular vision training group exhibited significantly superior stereoacuity and fusion convergence amplitude compared to the pencil push-up training group (P < 0.001). CONCLUSION: Both pencil push-up training and binocular vision training are effective in reducing exodeviation in patients with post-operative mild under-correction of intermittent exotropia. However, binocular vision training demonstrates superior efficacy in restoring stereopsis and fusion convergence amplitude compared to pencil push-up training.

Visual outcomes following bilateral implantation of a non-diffractive extended depth of focus toric intraocular lens using a mini-monovision approach.

PURPOSE: To evaluate the clinical outcomes following bilateral implantation of the AcrySof™ IQ Vivity™ toric extended depth of focus (EDOF) intraocular lens (IOL). DESIGN: Prospective interventional case series. METHODS: Patients with bilateral significant cataracts and pre-existing corneal astigmatism underwent cataract surgery and implantation with the AcrySof™ IQ Vivity™ toric IOL. Dominant eyes were targeted at emmetropia and non-dominant eyes at -0.50D. Primary endpoints were binocular uncorrected distance (UDVA), intermediate (UIVA at 66 cm) and near (UNVA at 40 cm) acuities at 3 months. Secondary outcomes were corrected distance (CDVA), distance corrected intermediate (DCIVA) and distance corrected near (DCNVA), refractive predictability, rotational stability, binocular defocus curve, contrast sensitivity, Questionnaire for Visual Disturbances (QUVID) and Visual Function Index (VF-14) questionnaire scores. All visual acuities were converted to logarithm of minimum angle of resolution (logMAR) for analysis. RESULTS: 30 patients underwent uneventful phacoemulsification. The mean binocular UDVA, UIVA and UNVA were 0.06 ± 0.12, 0.11 ± 0.10 and 0.26 ± 0.10 respectively. The mean refractive spherical equivalent (MRSE) for dominant and non-dominant eyes were - 0.07D ± 0.27 and - 0.12D ± 0.54 respectively. 92.4% of dominant eyes and 84.6% of non-dominant eyes within 0.50D of target. The mean IOL rotation was 3.85° ± 5.09 with 86.7% of eyes with less than 5° of rotation. 26.7%, 20% and 36.7% of patients reported starbursts, haloes and glare respectively. The mean VF-14 score was 91.77. CONCLUSION: Bilateral implantation of the AcrySof™ IQ Vivity™ Toric IOL resulted in very good unaided visual acuities for far and intermediate distance with functional near vision. Dysphotopsias were reported but despite this, a high level of visual function was achieved.

Influence of scene aspect ratio and depth cues on verticality perception bias.

Perceiving verticality is crucial for accurate spatial orientation. Previous research has revealed that tilted scenes can bias verticality perception. Verticality perception bias can be represented as the sum of multiple periodic functions that play a role in the perception of visual orientation, where the specific factors affecting each periodicity remain uncertain. This study investigated the influence of the width and depth of an indoor scene on each periodic component of the bias. The participants were presented with an indoor scene showing a rectangular checkerboard room (Experiment 1), a rectangular aperture on the wall (Experiment 2), or a rectangular dotted room (Experiment 3), with various aspect ratios. The stimuli were presented with roll orientations ranging from 90° clockwise to 90° counterclockwise. The participants were asked to report their subjective visual vertical (SVV) perceptions. The contributions of 45°, 90°, and 180° periodicities to the SVV error were assessed by the weighted vector sum model. In Experiment 1, the periodic components of the SVV error increased with the aspect ratio. In Experiments 2 and 3, only the 90° component increased with the aspect ratio. These findings suggest that extended transverse surfaces may modulate the periodic components of verticality perception.

Pictorial depth cues elicit the perception of tridimensionality in dogs.

The perception of tridimensionality is elicited by binocular disparity, motion parallax, and monocular or pictorial cues. The perception of tridimensionality arising from pictorial cues has been investigated in several non-human animal species. Although dogs can use and discriminate bidimensional images, to date there is no evidence of dogs' ability to perceive tridimensionality in pictures and/or through pictorial cues. The aim of the present study was to assess the perception of tridimensionality in dogs elicited by two pictorial cues: linear perspective and shading. Thirty-two dogs were presented with a tridimensional stimulus (i.e., a ball) rolling onto a planar surface until eventually falling into a hole (control condition) or until reaching and rolling over an illusory hole (test condition). The illusory hole corresponded to the bidimensional pictorial representation of the real hole, in which the pictorial cues of shading and linear perspective created the impression of tridimensionality. In a violation of expectation paradigm, dogs showed a longer looking time at the scene in which the unexpected situation of a ball rolling over an illusory hole occurred. The surprise reaction observed in the test condition suggests that the pictorial cues of shading and linear perspective in the bidimensional image of the hole were able to elicit the perception of tridimensionality in dogs.

The relation between visual functions, functional vision, and bimanual function in children with unilateral cerebral palsy.

BACKGROUND: Accurate visual information is needed to guide and perform efficient movements in daily life. AIMS: To investigate the relation between visual functions, functional vision, and bimanual function in children with unilateral cerebral palsy (uCP). METHODS AND PROCEDURES: In 49 children with uCP (7-15 y), we investigated the relation between stereoacuity (Titmus Stereo Fly test), visual perception (Test of Visual Perceptual Skills), visuomotor integration (Beery Buktenica Test of Visual-Motor Integration) and functional vision (Flemish cerebral visual impairment questionnaire) with bimanual dexterity (Tyneside Pegboard Test), bimanual coordination (Kinarm exoskeleton robot, Box opening task), and functional hand use (Children's Hand-use Experience Questionnaire; Assisting Hand Assessment) using correlations (rs) and elastic-net regularized regressions (d). OUTCOMES AND RESULTS: Visual perception correlated with bimanual coordination (rs=0.407-0.436) and functional hand use (rs=0.380-0.533). Stereoacuity (rs=-0.404), visual perception (rs=-0.391 to -0.620), and visuomotor integration (rs=-0.377) correlated with bimanual dexterity. Functional vision correlated with functional hand use (rs=-0.441 to -0.458). Visual perception predicted bimanual dexterity (d=0.001-0.315), bimanual coordination (d=0.004-0.176), and functional hand use (d=0.001-0.345), whereas functional vision mainly predicted functional hand use (d=0.001-0.201). CONCLUSIONS AND IMPLICATIONS: Visual functions and functional vision are related to bimanual function in children with uCP highlighting the importance of performing extensive visual assessment to better understand children's difficulties in performing bimanual tasks. WHAT THIS PAPER ADDS: Previous findings showed that up to 62 % of children with unilateral cerebral palsy (uCP) present with visual impairment, which can further compromise their motor performance. However, the relation between visual and motor function has hardly been investigated in this population. This study makes a significant contribution to the literature by comprehensively investigating the multi-level relation between the heterogenous spectrum of visual abilities and bimanual function in children with uCP. We found that mainly decreased visual perception was related to decreased bimanual dexterity, bimanual coordination, and functional hand use while impairments in functional vision were only related to decreased functional hand use. Additionally, elastic-net regression models showed that visual assessments can predict bimanual function in children with uCP, however, effect sizes were only tiny to small. With our study, we demonstrated a relation between visual functions and bimanual function in children with uCP. These findings suggest the relevance of thoroughly examining visual functions in children with uCP to identify the presence of visual impairments that may further compromise their bimanual function.

Comparison of Depth-Related Visuomotor Task Performance in Uniocular Individuals and in Binocular Controls With and Without Temporary Monocular Occlusion.

Purpose: Do one-eyed (uniocular) humans use monocular depth cues differently from those with intact binocularity to perform depth-related visuomotor tasks that emulate complex activities of daily living? If so, does performance depend on the participant's age, duration of uniocularity and head movements? Methods: Forty-five uniocular cases (age range 6-37 years; 2.4 months-31.0 years of uniocularity) and 46 age-similar binocular controls performed a task that required them to pass a hoop around an electrified wire convoluted in depth multiple times, while avoiding contact as indicated by auditory feedback. The task was performed with and without head restraint, in random order. The error rate and speed were calculated from the frequency of contact between the hoop and wire and the total task duration (adjusting for error time), respectively, all determined from video recordings of the task. Head movements were analyzed from the videos using face-tracking software. Results: Error rate decreased with age (P < 0.001) until the late teen years while speed revealed no such trend. Across all ages, the error rate increased and speed decreased in the absence of binocularity (P < 0.001). There was no additional error reduction with duration of uniocularity (P = 0.16). Head movements provided no advantage to task performance, despite generating parallax disparities comparable to binocular viewing. Conclusions: Performance in a dynamic, depth-related visuomotor task is reduced in the absence of binocular viewing, independent of age-related performance level. This study finds no evidence for a prolonged experience with monocular depth cues being advantageous for such tasks over transient loss of binocularity.

The human brain deals with violating general color or depth knowledge in different time courses.

Utilizing the high temporal resolution of event-related potentials (ERPs), we compared the time course of processing incongruent color versus 3D-depth information. Participants were asked to judge whether the food color (color condition) or 3D structure (3D-depth condition) was congruent or incongruent with their previous knowledge and experience. The behavioral results showed that the reaction times in the congruent 3D-depth condition were slower than those in the congruent color condition. The reaction times in the incongruent 3D-depth condition were slower than those in the incongruent color condition. The ERP results showed that incongruent color stimuli induced a larger N270, larger P300, and smaller N400 components in the fronto-central region than the congruent color stimuli. Incongruent 3D-depth stimuli induced a smaller N1 in the occipital region, larger P300 and smaller N400 in the parietal-occipital region than congruent 3D-depth stimuli. The time-frequency analysis found that incongruent color stimuli induced a larger theta band (360-580 ms) activation in the fronto-central region than congruent color stimuli. Incongruent 3D-depth stimuli induced larger alpha and beta bands (240-350 ms) activation in the parietal region than congruent 3D-depth stimuli. Our results suggest that the human brain deals with violating general color or depth knowledge in different time courses. We speculate that the depth perception conflict was dominated by solving the problem with visual processing, whereas the color perception conflict was dominated by solving the problem with semantic violation.

Clinical Outcomes of a Toric Enhanced Depth-of-Focus Intraocular Lens Based on the Combination of 4th- and 6th-Order Spherical Aberration.

PURPOSE: To assess the visual and refractive outcomes of patients implanted with a toric extended depth-of-focus (EDOF) intraocular lens (IOL) following cataract surgery. METHODS: A total of 44 eyes implanted with the EDOF LuxSmart toric IOL were evaluated 4 to 6 months postoperatively. The main outcomes measurements evaluated were refractive error, rotational stability, distance, intermediate, and near visual acuities, defocus curve, photopic and mesopic contrast sensitivity, wavefront aberrations, and modulation transfer function, and the Catquest-9SF-questionnaire. RESULTS: The mean postoperative spherical equivalent and cylinder were -0.02 ± 0.26 and -0.17 ± 0.29 diopters (D), respectively. A total of 90.45% and 100% of the eyes had a postoperative spherical equivalent within ±0.50 and ±1.00 D, respectively (this being 93.18% and 100% for the refractive cylinder). The mean rotational stability was 0.61 ± 1.61 degrees. The mean binocular corrected distance visual acuity (CDVA), corrected distance intermediate visual acuity (CDIVA), and corrected distance near visual acuity (CDNVA) were -0.02 ± 0.06, 0.07 ± 0.08, and 0.26 ± 0.09 logMAR, respectively. The CDVA was 20/25 or better in 95.45% of patients, CDIVA was 20/25 or better in 72.73%, and CDNVA was 20/40 or better in 72.73%. The defocus curve showed good visual acuity at distance and intermediate vergences. The contrast sensitivity and optical quality outcomes were good with mean higher order, spherical, and coma aberration values of 0.161 ± 0.155, -0.019 ± 0.048, and 0.080 ± 0.065 µm, respectively. A total of 90.9% of patients were either fairly satisfied or very satisfied with their vision after the surgery, and 77.7% of patients reported no difficulties when reading text in newspapers. CONCLUSIONS: Implantation of the toric pure refractive EDOF technology IOL provides good refractive, optical, and visual quality at different distances, with high levels of patient satisfaction being reported. [J Refract Surg. 2024;40(6):e398-e406.].

Comparison of Foraging Interactive D-prime and Angular Indication Measurement Stereo with different methods to assess stereopsis.

PURPOSE: Stereopsis is a critical visual function, however clinical stereotests are time-consuming, coarse in resolution, suffer memorization artifacts, poor repeatability, and low agreement with other tests. Foraging Interactive D-prime (FInD) Stereo and Angular Indication Measurement (AIM) Stereo were designed to address these problems. Here, their performance was compared with 2-Alternative-Forced-Choice (2-AFC) paradigms (FInD Stereo only) and clinical tests (Titmus and Randot) in 40 normally-sighted and 5 binocularly impaired participants (FInD Stereo only). METHODS: During FInD tasks, participants indicated which cells in three 4*4 charts of bandpass-filtered targets (1,2,4,8c/° conditions) contained depth, compared with 2-AFC and clinical tests. During the AIM task, participants reported the orientation of depth-defined bars in three 4*4 charts. Stereoscopic disparity was adaptively changed after each chart. Inter-test agreement, repeatability and duration were compared. RESULTS: Test duration was significantly longer for 2-AFC (mean = 317s;79s per condition) than FInD (216s,18s per chart), AIM (179s, 60s per chart), Titmus (66s) or RanDot (97s). Estimates of stereoacuity differed across tests and were higher by a factor of 1.1 for AIM and 1.3 for FInD. No effect of stimulus spatial frequency was found. Agreement among tests was generally low (R2 = 0.001 to 0.24) and was highest between FInD and 2-AFC (R2 = 0.24;p<0.01). Stereoacuity deficits were detected by all tests in binocularly impaired participants. CONCLUSIONS: Agreement among all tests was low. FInD and AIM inter-test agreement was comparable with other methods. FInD Stereo detected stereo deficits and may only require one condition to identify these deficits. AIM and FInD are response-adaptive, self-administrable methods that can estimate stereoacuity reliably within one minute.

Playing three-dimensional video games boosts stereo vision.

Playing two-dimensional video games has been shown to result in improvements in a range of visual and cognitive tasks, and these improvements appear to generalize widely1,2,3,4,5,6. Here we report that young adults with healthy vision, surprisingly, showed a dramatic improvement in stereo vision after playing three-dimensional, but not two-dimensional, video games for a relatively short period of time. Intriguingly, neither group showed any significant improvement in binocular contrast sensitivity. This dissociation suggests that the visual enhancement was specific to genuine stereoscopic processing, not indirectly resulting from enhanced contrast processing, and required engaging in a disparity cue-rich three-dimensional environment.

Risk Factors for Corneal Monochromatic Aberrations and Implications for Multifocal and Extended Depth-of-Focus Intraocular Lens Implantation.

PURPOSE: To discuss factors influencing corneal aberrations that might influence the optical quality after intraocular lens (IOL) implantation. METHODS: PubMed and Scopus were the main resources used to search the medical literature. An extensive search was performed to identify relevant articles concerning factors influencing the level of corneal aberrations as of August 27, 2023. The following keywords were used in various combinations: corneal, aberrations, defocus, astigmatism, spherical aberration, coma, trefoil, quadrafoil, intraocular lens, and IOL. RESULTS: Conclusive evidence is lacking regarding the correlation between age and changes in corneal aberrations. Patients with astigmatism have greater corneal higher-order aberrations than those with minimal astigmatism, particularly concerning trefoil and coma. Increased levels of corneal higher-order aberrations are noted following contact lens wear, in patients with dry eye disease, and with pterygium. Increased higher-order aberrations have been reported following corneal refractive surgery and for 3 months following trabeculectomy; regarding intraocular lens surgery, the results remain controversial. CONCLUSIONS: Several factors influence the level of corneal higher-order aberrations. Multifocal and extended depth-of-focus IOLs can share similarities in their optical properties, and the main difference arises in their design and performance with respect to spherical aberration. Preoperative evaluation is critical for proper IOL choice, particularly in corneas with risk of high levels of aberrations. [J Refract Surg. 2024;40(6):e420-e434.].

Complexity of mental geometry for 3D pose perception.

Biological visual systems rely on pose estimation of 3D objects to navigate and interact with their environment, but the neural mechanisms and computations for inferring 3D poses from 2D retinal images are only partially understood, especially where stereo information is missing. We previously presented evidence that humans infer the poses of 3D objects lying centered on the ground by using the geometrical back-transform from retinal images to viewer-centered world coordinates. This model explained the almost veridical estimation of poses in real scenes and the illusory rotation of poses in obliquely viewed pictures, which includes the "pointing out of the picture" phenomenon. Here we test this model for more varied configurations and find that it needs to be augmented. Five observers estimated poses of sloped, elevated, or off-center 3D sticks in each of 16 different poses displayed on a monitor in frontal and oblique views. Pose estimates in scenes and pictures showed remarkable accuracy and agreement between observers, but with a systematic fronto-parallel bias for oblique poses similar to the ground condition. The retinal projection of the pose of an object sloped wrt the ground depends on the slope. We show that observers' estimates can be explained by the back-transform derived for close to the correct slope. The back-transform explanation also applies to obliquely viewed pictures and to off-center objects and elevated objects, making it more likely that observers use internalized perspective geometry to make 3D pose inferences while actively incorporating inferences about other aspects of object placement.