Study of stereopsis using a depth sensation detection platform equipped with computer vision technology (DALE3D) / Estudio de estereopsis mediante una plataforma de detección de sensaciones de profundidad equipada con tecnología de visión por ordenador (DALE3D)

Background and objectives: The invention described herein is a prototype based on computer vision technology that measures depth perception and is intended for the early examination of stereopsis. Materials and methods: The prototype (software and hardware) is a depth perception measurement system that consists on: (a) a screen showing stereoscopic models with a guide point that the subject must point to; (b) a camera capturing the distance between the screen and the subject's finger; and (c) a unit for recording, processing and storing the captured measurements. For test validation, the reproducibility and reliability of the platform were calculated by comparing results with standard stereoscopic tests. A demographic study of depth perception by subgroup analysis is shown. Subjective comparison of the different tests was carried out by means of a satisfaction survey. Results: We included 94 subjects, 25 children and 69 adults, with a mean age of 34.2 ± 18.9 years; 36.2 % were men and 63.8 % were women. The DALE3D platform obtained good repeatability with an interclass correlation coefficient (ICC) between 0.94 and 0.87, and coefficient of variation (CV) between 0.1 and 0.26. Threshold determining optimal and suboptimal results was calculated for Randot and DALE3D test. Spearman's correlation coefficient, between thresholds was not statistically significant (p value > 0.05). The test was considered more visually appealing and easier to use by the participants (90 % maximum score). Conclusions: The DALE3D platform is a potentially useful tool for measuring depth perception with optimal reproducibility rates. Its innovative design makes it a more intuitive tool for children than current stereoscopic tests. Nevertheless, further studies will be needed to assess whether the depth perception measured by the DALE3D platform is a sufficiently reliable parameter to assess stereopsis.(AU)

Six-month binocular stereopsis recovery and its influencing factors in children with intermittent exotropia.

OBJECTIVE: To investigate the recovery of binocular stereopsis recovery and its influencing factors in children with intermittent exotropia after successful correction of eye position. METHODS: Prospective clinical study. A total of 178 patients, aged 9 ∼ 14 (10.8 ± 1.7) years, who were successfully corrected after intermittent exotropia surgery at the Beijing Tongren Hospital Affiliated to Capital Medical University from October 2023 to September 2023 were collected, the follow-up duration was six-month or longer. Paired t test, Pearson correlation analysis and multivariable linear regression analysis were used to probe preoperative clinical features that may predict the stereopsis six months after surgery. RESULTS: Six months after surgery, the angle of deviation of the patients met the orthotopic standard, and there was significant difference compared with that before surgery (distant: -2.7△±3.2△ vs. -30.5△±8.4△, t=-25.3, P < 0.001. Near:-3.7△±4.1△ vs. -33.7△±8.0△, t=-26.1, P < 0.001). Distant stereopsis (3.0 ± 0.6 vs. 3.9 ± 0.4, t = 4.9, P < 0.05) and near stereopsis (2.3 ± 0.5 vs. 2.6 ± 0.4, t = 3.8, P < 0.05) were both significantly improved compared with that of before surgery. 17% and 22% patients rebuilt normal distant stereopsis and normal near stereopsis, respectively. Preoperative distant stereopsis (r=-0.26, P = 0.004) and near stereopsis (r=-0.23, P = 0.011) was significantly negatively correlated with convergence reserve. Multivariable analysis showed that patients' age (ß = 0.003, p = 0.037), anisometropia (ß = 0.015, p = 0.043), and preoperative distant stereopsis (ß = 0.456, p < 0.001) were significantly associated with postoperative distant stereopsis. Patients' age (ß = 0.005, p = 0.044), anisometropia (ß = 0.127, p = 0.034), angle of deviation (ß=-0.230, p = 0.020), and preoperative near stereopsis (ß = 0.136, p < 0.001) were significantly associated with postoperative near stereopsis. CONCLUSION: IXT patients could get eye position fixed after surgery, about 20% patients benefited from stereopsis improvement. Patient's age, binocular anisometropia, angle of deviation and preoperative stereopsis were independent factors influencing postoperative stereopsis.

Non-Invasive Recording of Ocular-Following Responses in Children: A Promising Tool for Stereo Deficiency Evaluation.

Background: The ability to merge the two retinal images to perceive depth (stereopsis) plays an important role in human vision. Its proper development requires binocular alignment and good visual acuity in both eyes during childhood. Because treatments are more effective when applied early, early diagnosis is important. Unfortunately, assessing stereo deficiencies in infants and young children remains challenging. Recently, it has been shown that ocular-following responses (OFRs; reflexive, short-latency eye movements induced by the sudden motion of a large textured pattern) are sensitive to changes in interocular correlation, making them potentially useful for stereo deficiency assessments. To test this hypothesis, we measured OFRs elicited by dichoptic stimulation in children with normal and compromised stereopsis (due to amblyopia). Methods: Two groups of six children (age- and sex-matched: 3M/3F aged 7-12 yo), one with compromised stereopsis and one with normal stereopsis, were included. OFRs were recorded using a custom high-resolution video eye-tracking system. The relative differences between eye displacement induced by correlated stimuli (up-correlated-down-correlated) and anticorrelated (up-anticorrelated-down-anticorrelated) were compared. Results: We found significant differences between OFRs induced by two dichoptic conditions (correlated and anticorrelated stimuli) in most children with normal stereopsis, whereas no differences were observed in children with compromised stereopsis, indicating a lack of disparity detectors. Conclusions: OFRs might thus be exploited as a diagnostic tool for the objective identification of stereo deficiencies in children. This might lead to improved early diagnosis and treatment outcomes for conditions like amblyopia and strabismus.

A comparative study of stereopsis in term and preterm children with and without retinopathy of prematurity.

PURPOSE: To evaluate stereopsis in term-born, preterm, and preterm children with and without retinopathy of prematurity (ROP) and its treatment. METHODS: The cross-sectional study included 322 children between 3 and 11 years of age born term or preterm, with or without ROP, and with or without treatment for ROP. The ROP treatments were laser therapy, intravitreal injection (IVI) of anti-vascular endothelial growth factor, or their combination. Stereoacuity was measured using the Titmus Stereo Test, and the results among various age groups were analyzed. RESULTS: Stereopsis was found to improve with increasing age at testing (P < 0.001) across the entire study population. The term group exhibited significantly better stereoacuity than the preterm group (P < 0.001). At 3-5 years and 6-8 years, the preterm children without ROP exhibited significantly better stereoacuity than did those with ROP (P < 0.001 and P = 0.02, respectively); however, at 9-11 years, both groups exhibited similar stereoacuity (P = 0.34). The stereoacuity in the children with untreated ROP was similar to that of the children with treated ROP in all age groups (P > 0.05). No significant differences in stereopsis were identified between children with ROP treated with laser versus with IVI (P > 0.05). From multivariate analysis, younger age at testing (P = 0.001) and younger gestational age (P < 0.001) were associated with poorer stereopsis. CONCLUSIONS: Stereopsis development gradually improved with age in all groups. The children born preterm exhibited poorer stereoacuity than those born term. Children with ROP treated with laser photocoagulation versus IVI may exhibit similar levels of stereoacuity. Younger age at testing and gestational age were independent risk factors for poorer stereoacuity.

Binocular function in the aging visual system: fusion, suppression, and stereoacuity.

Introduction: Changes in vision that occur in normal healthy aging can be seen in fundamental measures of monocular vision. However, the nature of the changes in binocular vision with age remain unclear. Methods: A total of 28 older (53-66 years) and 28 younger adults (20-31 years) were enrolled in this study. We performed a battery of tests to assess differences in monocular contrast thresholds and various binocular visual functions including dichoptic masking weight and strength, the binocular balance point for fused stimuli, and stereoacuity in the aging and control groups. Results: Aging significantly increased monocular contrast thresholds (p < 0.001). Although this suggests that aging reduces the effective "input gain" to vision, we also found a significantly elevated contribution of those weaker signals to interocular suppression (p < 0.001). Consequently, there was no significant net difference in the strength of interocular suppression (p = 0.065). We did not find a significant difference of absolute balance point between the two groups (p = 0.090). Lastly, the mean stereoacuity was worse in the older group compared to the younger group (p = 0.002). Discussion: Our findings confirm previous results showing differences in contrast sensitivity and stereoacuity with aging. Furthermore, we find a change in interocular suppression that is a possible consequence of the change in contrast sensitivity. It is suggestive of a cortical system that maintains a homeostatic balance in interocular suppression across the lifespan.

A comparative study of stereopsis measurements: analyzing natural conditions versus dichoptic presentation using smartphones and ultraviolet printer technology.

Background: Accurate differentiation between stereopsis assessments in the natural and dichoptic presentation states has proven challenging with commercial stereopsis measurement tools. This study proposes a novel method to delineate these differences more precisely. Methods: We instituted two stereopsis test systems predicated on a pair of 4K smartphones and a modified Frisby Near Stereotest (FNS) version. Stereoacuity was evaluated both in the natural environment state (via the modified FNS) and the dichoptic state (via smartphones). Thirty subjects aged 20 to 28 years participated in the study with the best-corrected visual acuity (VA) of each eye no less than 0 logMAR and stereoauity of no worse than 40″. Varying degrees of monocular VA loss were induced using the fogging method, while this study does not explore conditions where the VA of both eyes is worse than 0 logMAR. Results: When the VA difference between the two eyes did not exceed 0.2 logMAR, the modified FNS produced lower stereoacuity values compared to the 4K smartphones (Wilcoxon signed-rank test: difference = 0 logMAR, Z = -3.879, P < 0.001; difference = 0.1 logMAR, Z = -3.478, P = 0.001; difference = 0.2 logMAR, Z = -3.977, P < 0.001). Conversely, no significant differences were observed when the binocular vision difference exceeded 0.2 logMAR (difference = 0.3 logMAR, Z = -1.880, P = 0.060; difference = 0.4 logMAR, Z = -1.784, P = 0.074; difference = 0.5 logMAR, Z = -1.812, P = 0.070). Conclusion: The findings suggest that stereoacuity values measurements taken in the natural environment state surpass those derived from the dichoptic presentation. However, the observed difference diminishes as stereopsis decreases, corresponding to an increase in induced anisometropia.

Study of stereopsis using a depth sensation detection platform equipped with computer vision technology (DALE3D).

BACKGROUND AND OBJECTIVES: The invention described herein is a prototype based on computer vision technology that measures depth perception and is intended for the early examination of stereopsis. MATERIALS AND METHODS: The prototype (software and hardware) is a depth perception measurement system that consists on: (a) a screen showing stereoscopic models with a guide point that the subject must point to; (b) a camera capturing the distance between the screen and the subject's finger; and (c) a unit for recording, processing and storing the captured measurements. For test validation, the reproducibility and reliability of the platform were calculated by comparing results with standard stereoscopic tests. A demographic study of depth perception by subgroup analysis is shown. Subjective comparison of the different tests was carried out by means of a satisfaction survey. RESULTS: We included 94 subjects, 25 children and 69 adults, with a mean age of 34.2 ± 18.9 years; 36.2 % were men and 63.8 % were women. The DALE3D platform obtained good repeatability with an interclass correlation coefficient (ICC) between 0.94 and 0.87, and coefficient of variation (CV) between 0.1 and 0.26. Threshold determining optimal and suboptimal results was calculated for Randot and DALE3D test. Spearman's correlation coefficient, between thresholds was not statistically significant (p value > 0.05). The test was considered more visually appealing and easier to use by the participants (90 % maximum score). CONCLUSIONS: The DALE3D platform is a potentially useful tool for measuring depth perception with optimal reproducibility rates. Its innovative design makes it a more intuitive tool for children than current stereoscopic tests. Nevertheless, further studies will be needed to assess whether the depth perception measured by the DALE3D platform is a sufficiently reliable parameter to assess stereopsis.

Lack of stereopsis does not reduce surgical performance but prolongs the learning curve of vitreoretinal surgery.

PURPOSE: To investigate whether individuals with long-term reduced stereopsis were able to obtain the same level of surgical skills in simulated vitreoretinal surgery on the Eyesi Surgical Simulator as individuals with normal stereopsis. METHODS: Twenty-four medical students were recruited and divided into two groups according to their degree of stereopsis: Group 1 (n = 12) included subjects with normal stereopsis (60 arcsec or lower) and Group 2 (n = 12) included subjects with reduced stereopsis (120 arcsec or higher). Stereopsis was tested using the TNO test (Lameris Ootech BV, Nieuwegein, the Netherlands). The participants were trained in virtual reality-simulated vitreoretinal surgery and continuously measured using a test with solid validity evidence and a pre-defined pass-fail score. All data were analysed using the Wilcoxon rank sum test. RESULTS: We observed no differences in overall performance scores for any of the four modules. The participants with reduced stereopsis used 5.8 more attempts in bimanual training (p = 0.04), 8.8 more attempts in removal of posterior hyaloid (p = 0.04), 9.1 more attempts in navigation training (p = 0.20) and 0.3 fewer attempts in removal of internal limiting membrane (p = 0.69). CONCLUSION: The final performance scores on the Eyesi Surgical Simulator were independent of the degree of stereopsis. However, the number of attempts to achieve the pre-defined pass-fail score increased significantly with reduced stereopsis in two of four modules. These results indicate that a high degree of stereopsis is not necessary to become proficient in microsurgery but may prolong the learning curve.

Relationship between dynamic visual acuity and static visual acuity, refractive error, and binocular vision in elite soccer players.

CLINICAL RELEVANCE: In many sports, dynamic visual acuity is used. In order to improve dynamic visual acuity, it is important to understand the aspects of the visual system that can cause compromise. BACKGROUND: To investigate the parameters of the visual system that may influence dynamic visual acuity in professional soccer players. METHODS: In 2022, 40 professional players were analysed. Screening consisted of a survey, the measurement refractive error, and static and dynamic visual acuity and the binocular vision parameters. All athletes were men with a mean age of 24.9 ± 4.8 years. RESULTS: The mean refractive error was -0.29 ± 0.61D, and 22.5% of athletes are myopic only and 7.5% hyperopic. Static visual acuity was R: -0.037 ± 0.094 LogMAR , L: -0.036 ± 0.098 LogMAR. Dynamic visual acuity was 0.154 ± 0.118 LogMAR . There is a positive and moderate correlation between monocular static visual acuity and dynamic visual acuity, with r = 0.524 (r2 = 0.275 , p < 0.001) for the right eye and r = 0.553 (r2 = 0.306, p < 0.001) for the left eye. For the component of astigmatism (J = 0) and for stereopsis in distance vision, the correlation was, r = -0.472 (r2 = 0.223, p = 0.002) and r = -0.467 (r2 = 0.218, p = 0.002), respectively. CONCLUSION: Athletes with lower static visual acuity in distance vision, or with worse stereopsis in distance vision or more myopic astigmatism, have lower dynamic visual acuity than other athletes.

Evaluation of visual plasticity in patients with refractive amblyopia treated using a visual perceptual learning system.

BACKGROUND: Amblyopia is a neurological deficit in binocular vision that affects 3% of the population and is the result of disruptions in early visual development. OBJECTIVE: In this study, we used a visual perceptual learning system for the short-term treatment of children with ametropic amblyopia and evaluated the clinical efficacy of this system in terms of visual plasticity. METHODS: We conducted a retrospective analysis of the clinical data of 114 children (228 eyes) with refractive amblyopia, who were aged 6.51 ± 1.51 years. Prior to the treatment, we evaluated all children with amblyopia using the visual information processing test. We determined the type of amblyopic defect according to the type of amblyopia, corrected visual acuity, and advanced visual function test results. Based on the type of defect, each child with amblyopia was given short-term visual perception training for 10 days. Finally, we compared the results of visual acuity and visual information processing tests before and after the treatment. RESULTS: The best-corrected visual acuity of patients was better after 10 days of visual training than that before training (P< 0.05). The perceptual eye position after training improved with statistically significant differences in horizontal and vertical perceptual eye position (both P< 0.05) compared to that before training. The number of amblyopic children without suppression in both eyes was 81 cases (71.1%) after training which was higher than that (65 cases, or 57.0%) before training, with a statistically significant difference (P< 0.05). Binocular fine stereopsis and dynamic stereopsis improved after training with a statistically significant difference (both P< 0.05). CONCLUSION: In this study, it was found that patients with amblyopia showed visual plasticity. Moreover, continuous visual perceptual learning improved the best-corrected visual acuity and recovered stereopsis in children with refractive amblyopia.

Treatment of Anisometropic Amblyopia with a Dichoptic Digital Platform in Argentinian Children and Adults.

PURPOSE: To evaluate and compare the results of dichoptic training in Argentinian children and adults with anisometropic amblyopia. METHODS: Prospective non-comparative study enrolling 41 subjects with anisometropic amblyopia (age, 6-60 years old). Two groups were differentiated according to age, children (6-16 years, 24 subjects) and adults (>17 years, 17 subjects). All patients were treated with the Bynocs® platform (Kanohi Eye Pvt. Ltd, India) following a protocol of 30 sessions of training of 30 min daily 5 times a week for 6 weeks. Changes in corrected distance visual acuity (CDVA) and binocular function (BF) score with treatment were analyzed. RESULTS: In the whole sample, CDVA in the amblyopic eye improved significantly, with a mean change of 0.30 logMAR (p < .001). Likewise, a significant improvement was also found in BF score (p < .001), with a mean change of 1.14 log units. The change achieved in CDVA was significantly correlated with the baseline CDVA in the amblyopic eye (r=-0.568, p < .001). Furthermore, no significant differences were found between age groups in the change achieved in CDVA (p = .431) and BF with therapy (p = .760). CONCLUSIONS: Dichoptic training with the digital platform evaluated provides an effective improvement of visual acuity and binocular function in children and adults with anisometropic amblyopia.

Hierarchical computation of 3D motion across macaque areas MT and FST.

Computing behaviorally relevant representations of three-dimensional (3D) motion from two-dimensional (2D) retinal signals is critical for survival. To ascertain where and how the primate visual system performs this computation, we recorded from the macaque middle temporal (MT) area and its downstream target, the fundus of the superior temporal sulcus (area FST). Area MT is a key site of 2D motion processing, but its role in 3D motion processing is controversial. The functions of FST remain highly underexplored. To distinguish representations of 3D motion from those of 2D retinal motion, we contrast responses to multiple motion cues during a motion discrimination task. The results reveal a hierarchical transformation whereby many FST but not MT neurons are selective for 3D motion. Modeling results further show how generalized, cue-invariant representations of 3D motion in FST may be created by selectively integrating the output of 2D motion selective MT neurons.

Terapias de estimulación visual y rendimiento académico de niños de primer año de Educación Básica / Visual stimulation therapies and academic performance of children in the first year of Elementary School / Terapias de estimulação visual e desempenho acadêmico de crianças no primeiro ano do Ensino Fundamental

La terapia visual como tratamiento de estimulación neurofisiológica, permite el desarrollo y mejoría de las habilidades visuales; mismas que inciden de manera directa en el aprendizaje y la lectura. Objetivo. Evaluar el impacto de las terapias de estimulación visual en el rendimiento académico en niños de primer año de básica de una unidad educativa privada en Quito-Ecuador. Materiales y métodos. La investigación fue descriptiva, modalidad de intervención educativa, con alcance explicativo causal y longitudinal. Se trabajó con una muestra intencional conformada por 32 estudiantes de 5 años cumplidos, ambos sexos biológicos, que asistían a clases presenciales, no recibían terapias visuales y, contaban con el consentimiento de los padres. Un profesional especialista en salud visual ejecutó la investigación en tres fases: 1) diagnóstica: medición de las variables como pre-test; 2) aplicación de estrategias: con el despliegue del programa por seis meses para trabajar la estimulación de habilidades visuo-perceptuales y; 3) evaluación del programa tras la intervención de las variables como post - test. Resultados. Tras las terapias, el 97% de la población tuvo un impacto positivo de +60, el porcentaje de agudeza visual inferior se redujo al 0%, incrementó la agudeza visual óptima en OD (43%) y OI (47%), la estereopsis mejoró en un 84% de sujetos, las habilidades visuo-perceptuales fueron aceptables y se mejoró el rendimiento escolar. Conclusiones. Se pudo evidenciar que la estimulación de habilidades visuales a través de terapias específicas, en edades tempranas, es importante y necesaria para evitar problemas futuros en el aprendizaje.

Visual therapy as a treatment of neurophysiological stimulation, allows the development and improvement of visual skills, which have a direct impact on learning and reading. Objective. To evaluate the impact of visual stimulation therapies on the academic performance of children in the first year of elementary school in a private educational unit in Quito-Ecuador. Materials and methods. The research was descriptive, educational intervention modality, with causal and longitudinal explanatory scope. We worked with an intentional sample of 32 students of 5 years of age, both biological sexes, who attended presential classes, did not receive visual therapies and had parental consent. A professional specialist in visual health carried out the research in three phases: 1) diagnostic: measurement of the variables as a pre-test; 2) application of strategies: with the deployment of the program for six months to work on the stimulation of visual-perceptual skills and; 3) evaluation of the program after the intervention of the variables as a post-test. Results. After the therapies, 97% of the population had a positive impact of +60, the percentage of inferior visual acuity was reduced to 0%, optimal visual acuity increased in OD (43%) and OI (47%), stereopsis improved in 84% of subjects, visuo-perceptual skills were acceptable and school performance was improved. Conclusions. It could be evidenced that the stimulation of visual skills through specific therapies, at early ages, is important and necessary to avoid future learning problems.

A terapia visual como um tratamento de estimulação neurofisiológica permite o desenvolvimento e a melhoria das habilidades visuais, que têm um impacto direto no aprendizado e na leitura. Objetivo. Avaliar o impacto das terapias de estimulação visual no desempenho acadêmico de crianças no primeiro ano do ensino fundamental em uma unidade educacional privada em Quito-Equador. Materiais e métodos. A pesquisa foi descritiva, na modalidade de intervenção educacional, com um escopo explicativo causal e longitudinal. Trabalhamos com uma amostra intencional de 32 alunos de 5 anos de idade, de ambos os sexos biológicos, que frequentavam as aulas presenciais, não recebiam terapia visual e tinham o consentimento dos pais. Um profissional especialista em saúde visual realizou a pesquisa em três fases: 1) diagnóstico: mensuração das variáveis como pré-teste; 2) aplicação de estratégias: com a implantação do programa durante seis meses para trabalhar a estimulação das habilidades perceptivo-visuais e; 3) avaliação do programa após a intervenção das variáveis como pós-teste. Resultados. Após as terapias, 97% da população teve um impacto positivo de +60, a porcentagem de acuidade visual inferior foi reduzida para 0%, a acuidade visual ótima aumentou em OD (43%) e OI (47%), a estereopsia melhorou em 84% dos indivíduos, as habilidades visuo-perceptuais foram aceitáveis e o desempenho escolar melhorou. Conclusões. Foi possível demonstrar que a estimulação das habilidades visuais por meio de terapias específicas em uma idade precoce é importante e necessária para evitar futuros problemas de aprendizagem.

Binocular vision measurements with a new online digital platform: comparison with conventional clinical measures.

CLINICAL RELEVANCE: New digital systems are being developed for evaluating different aspects of the visual function, such as binocularity, and it is important to know their real performance in clinical practice in order to use them appropriately. BACKGROUND: The aim was to compare binocular vision measures obtained with an online digital platform with conventional measures using prisms and printed tests. METHODS: Prospective study enrolling 49 healthy patients (mean age: 35.5 ± 13.6 years). A complete visual examination was performed including measurement of near phoria (cover test), negative fusional vergence (NFV) and positive fusional vergence (PFV) ranges (prism bar), and stereopsis (24 patients Randot Stereo Test and 25 patients TNO Random Dot Test 19th edition). These same parameters were also measured with the Bynocs system (Kanohi Eye Pvt Ltd). Bland - Altman plots were used to analyse the agreement between methods. RESULTS: Digital measurement of near phoria was significantly lower than that obtained with the cover test, with a median difference (MD) of 4.71 (-0.07-20.07) prism dioptres (pd) (p < 0.001). No significant differences were found between Bynocs and prism bar methods in NFV break (MD 2.00, range -21-26 pd, p = 0.584) and recovery points (MD 0.00, range -16-24 pd, p = .571). Near PFV were significantly lower with Bynocs (break: MD -9.00, range -38-12 pd; recovery: MD -14.00, range -43-20 pd; p < 0.001). Bynocs stereoacuity threshold was significantly lower than that obtained with TNO (p = 0.004), but significantly higher compared to Randot (p < 0.001). Large and clinically relevant confidence intervals for the comparison between digital and conventional measures were detected in Passing-Bablok analysis. CONCLUSIONS: Digital measures of near phoria, NFV, PFV, and stereopsis with the Bynocs platform cannot be used interchangeably with conventional measures. The normal ranges of normality for this new tool are defined.

Association between stereoacuity and simulated clinical performance among dental students: an exploratory investigation.

INTRODUCTION: Dentistry is a profession that requires a high level of the hand-eye coordination. Although considerable attention has been put on dental students' manual dexterity, little emphasis was made on students' visual competency as a variable influencing their competency. In this study, we aimed to assess the association between dental students' stereopsis and their pre-clinical performance. METHODS: Dental students (n = 49) were required to perform the porcelain-fused-to-crown preparation for a lower first molar and an upper central incisor plastic teeth mounted on phantom heads. Performance was assessed by two faculty members based on two rubrics, which collectively included 11 assessment criteria. Afterward, students undertook a stereoacuity test using Randot stereotest. Stereopsis values greater than 40 arc/s were considered abnormal. RESULTS: A significant negative correlation was seen between stereopsis scores and students' grades for the upper incisor (p < 0.01), but not for the lower molar. An association was also seen between abnormal stereopsis and students' poor performance in preparing the finish line of the incisor tooth (p = 0.024). CONCLUSION: Abnormal stereopsis can impact dental students' performance, particularly when preparing teeth indirectly using a dental mirror. Dental educators should give attention to students' stereoacuity, in a manner similar to that given to students' manual dexterity.

Stereopsis after bilateral implantation of Toric intraocular lenses in high myopic cataract patients with astigmatism.

Purpose: To evaluate near, intermediate, distance visual acuity and stereopsis after bilateral implantation of Toric intraocular lenses (IOLs) in high myopic patients with astigmatism. Methods: Bilateral Toric or non-Toric IOL implantation (n â€‹= â€‹40 eyes each) was performed on high myopic cataract eyes with astigmatism. Best-corrected distance visual acuity (BCDVA), uncorrected intermediate visual acuity (UCIVA), uncorrected near visual acuity (UCNVA), residual refractive astigmatism (RRA), and near, intermediate, and distance stereoacuity were measured postoperatively at 7 days, 1 month, and 3 months. Results: The three-month postoperative BCDVA, UCIVA, and UCNVA of the Toric group were 0.08 â€‹± â€‹0.07, 0.30 â€‹± â€‹0.11, and 0.23 â€‹± â€‹0.14 LogMAR. All improved over the preoperative assessments (P â€‹< â€‹0.05). The RRA, UCIVA, and UCNVA were significantly better in the Toric group than the non-Toric group at all follow-up examinations (all P â€‹< â€‹0.05). At 3 months, the median near and intermediate stereoacuity of the Toric group were 100 (range 40 - 400) and 120 (range 50 - 400) arcsec, which were better than the non-Toric group (both P â€‹< â€‹0.05). Fine near stereopsis ≥100 arcsec was present in 65% of the Toric patients, and 50% had good intermediate stereopsis of ≥100 arcsec. However among non-Toric patients, only 15% and 5% achieved fine near and intermediate stereopsis. The postoperative BCDVA and best-corrected distance stereoacuity were similar in the two groups (P â€‹> â€‹0.05). Conclusions: In bilateral high myopic cataract patients with astigmatism, Toric IOLs not only improved UCIVA, UCNVA, and RRA, but also enhanced near and intermediate stereopsis acuity.

Digital Therapy for Visual Acuity and Binocular Function in Children with Anisometropic Amblyopia.

Amblyopia affects development of children's monocular vision and binocular function and becomes a largely intractable problem with increasing aging. This study is to investigate the binocular function and evaluate efficacy of digital therapy in children 8-13 years of age with anisometropic amblyopia. The patients in the digital therapy group performed the training with the digital amblyopia therapeutic software. The visual acuity and binocular function (perceptual eye position [PEP], suppression, and stereopsis) were examined at the first visit and 3-month post-treatment. Twenty-three cases in the control group and 25 cases in the digital therapy group were enrolled. The results revealed that 3-month digital therapy can effectively improve corrected distance visual acuity (CDVA) and improve the binocular function, including PEP, suppression, and second-order stereopsis in children with anisometropic amblyopia, 8-13 years of age. Digital therapy for amblyopia can effectively improve monocular CDVA of amblyopic eyes and binocular function in older children with anisometropic amblyopia.

The utility of peripheral stereopsis.

This perspective article makes the case for evaluating and training peripheral stereopsis, particularly when the central visual field is compromised in one or both eyes. Examples of clinical conditions that preferentially affect the central visual field include macular degeneration, which affects the central macular region in one or both eyes, and amblyopia where the central field is often affected in one eye, but the peripheral field is largely intact. While binocular acuity may be preserved when the monocular central field of one eye is affected, fine stereopsis is compromised because it requires intact vision in corresponding locations in the two eyes. Even in these clinical conditions, recent studies that map stereoacuity at locations across the visual field demonstrate that the periphery supports coarse stereopsis, and that training efforts to use residual stereopsis may have greater benefit if they take this finding into account.

Exploring the Effect of Preoperative Stereopsis on Visual Outcomes in Hyperopic Presbyopes Treated with PresbyOND® Laser Blended Vision Micro-Monovision.

We investigated the effects of Laser Blended Vision (LBV) on binocular summation and stereopsis in the treatment of presbyopia and hyperopia. Using a unidirectional, retrospective longitudinal design, data from 318 patients who underwent the Zeiss PresbyOND® LBV surgical procedure at Tecnolaser Clinic Vision Ophthalmology Center in Seville, Spain, were analyzed. The findings indicate that stereopsis quality significantly influenced short-term post-operative visual outcomes in measures like Uncorrected Distance and Near Visual Acuity (UDVA and UNVA). However, the impact of stereopsis on visual outcomes appeared to diminish over time, becoming statistically insignificant at the 12-month post-operative mark. The study suggests that while stereopsis is a crucial factor in the short term, its influence on visual outcomes tends to wane in the long-term postoperative period. Future studies are essential to elucidate the enduring clinical ramifications of these observations.