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1.
Curr Opin Ophthalmol ; 32(1): 45-53, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33122489

RESUMO

PURPOSE OF REVIEW: Corneal refractive surgery has achieved spectacle-free vision for millions of patients, but this aging population is now developing cataracts. Many of these patients may wish to avoid reliance on glasses after cataract surgery. Presbyopia-correcting intraocular lenses (IOLs) offer a solution, but corneal changes after refractive surgery may compound higher order aberrations and dysphotopic symptoms associated with these IOLs. This review aims to discuss potential factors that could aid in determining suitable postkeratorefractive candidates for presbyopia-correcting IOLs. RECENT FINDINGS: Studies investigating which preoperative measures influence outcomes are lacking. The few studies that have examined presbyopia-correcting IOLs in postkeratorefractive patients report that satisfactory outcomes are possible. However, recommendations for preoperative thresholds appear limited to expert opinion and studies involving virgin corneas. SUMMARY: As the number of presbyopia-correcting IOLs and postkeratorefractive patients grows, continued investigation into relevant preoperative factors and appropriate IOLs is required to make evidence-based decisions. The current literature shows that with rigorous counseling and appropriate patient selection, presbyopia-correcting IOLs can provide postkeratorefractive patients with satisfactory results and spectacle independence. In addition, the development of postoperative modifiable IOLs may prove to be the preferred option.


Assuntos
Implante de Lente Intraocular , Lentes Intraoculares Multifocais , Presbiopia/cirurgia , Percepção de Profundidade/fisiologia , Humanos , Ceratomileuse Assistida por Excimer Laser In Situ/efeitos adversos , Ceratectomia Fotorrefrativa/efeitos adversos , Presbiopia/etiologia , Presbiopia/fisiopatologia , Acuidade Visual/fisiologia
2.
Curr Opin Ophthalmol ; 32(1): 3-12, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33122490

RESUMO

PURPOSE OF REVIEW: The aim of this article is to review techniques to maximize all-distance uncorrected visual acuity and minimize photic phenomena after the implantation of multifocal and extended-depth of focus (EDOF) intraocular lenses (IOLs). This review examines the role of femtosecond laser-assisted cataract surgery (FLACS) in postoperative minimization of astigmatism and optimization of outcomes with multifocal and EDOF lenses. RECENT FINDINGS: By incorporating intraoperative and preoperative imaging, femtosecond platforms such as those that utilize iris or conjunctival vessel registration, can enable a precision of corneal incisions and toric IOL markings that enable the lowest possible postoperative levels of astigmatism. Current studies suggest that with increasing IOL complexity, that is, trifocal versus bifocal, image degradation with even low levels of postoperative astigmatism are increased. To this end, current data support the utility of femtosecond laser arcuate incisions to enable the achievement of 0.5 D or less postoperative astigmatism for best outcomes with multifocal lenses. SUMMARY: The synergistic combination of multifocal/EDOF IOLs with FLACS is an extremely promising route in achieving postoperative spectacle independence for patients. The marriage of the precision of FLACS with the increasing complexity of multifocal/EDOF IOLs will fuel nomogram adjustment and systematic improvements, such as the Wörtz-Gupta formula. Such strategies provide an unprecedented precision to cataract surgery that makes FOCUSED (Femtosecond Optimized Continuous Uncorrected Sight with EDOF and Diffractive Multifocal IOLs) a reality.


Assuntos
Percepção de Profundidade/fisiologia , Terapia a Laser/métodos , Implante de Lente Intraocular/métodos , Lentes Intraoculares Multifocais , Facoemulsificação , Acuidade Visual/fisiologia , Astigmatismo/fisiopatologia , Humanos , Pseudofacia/fisiopatologia , Refração Ocular/fisiologia
3.
PLoS One ; 15(9): e0237728, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32925945

RESUMO

PURPOSE: To investigate the influence of EDOF IOLs, TECNIS Symfony® (Johnson & Johnson Surgical Vision, Inc.), on visual field sensitivity and to compare the IOLs with other kinds of IOLs. METHODS: The subjects included the normal fellow eyes of patients who underwent the Humphrey Field Analyzer (HFA) 30-2 with Swedish Interactive Threshold Algorithm Fast within 6 months after cataract due to glaucoma or suspected glaucoma. Each parameter of HFA was compared among eyes implanted with TENIS Symfony® (EDOF group), diffractive bifocal IOLs (bifocal group), and monofocal IOLs (monofocal group). RESULTS: The total of 76 eyes, including 24 eyes in the EDOF group, 26 eyes in the bifocal group, and 26 eyes in the monofocal group, were included in this study. Mean deviation (MD) of HFA was -0.24±0.58 dB in the EDOF group, -1.38±0.58 dB in the bifocal group, and 0.02±0.44 dB in the monofocal group. Foveal threshold (FT) of HFA was 35.8±1.6 dB in the EDOF group, 33.6±1.7 dB in the bifocal group, and 36.6±1.4 dB in the monofocal group. In both MD and FT, there was significant difference between the bifocal group and the others (p<0.001). There was no difference between the EDOF group and the monofocal group. Moreover, there was no significant difference between the three groups about pattern standard deviation (PSD) of HFA. CONCLUSION: TECNIS Symfony® may have little influence on visual field sensitivity, whereas diffractive bifocal IOLs decrease visual field sensitivity.


Assuntos
Sensibilidades de Contraste/fisiologia , Percepção de Profundidade/fisiologia , Lentes Intraoculares , Campos Visuais/fisiologia , Idoso , Feminino , Humanos , Implante de Lente Intraocular , Masculino , Pessoa de Meia-Idade
4.
Middle East Afr J Ophthalmol ; 27(2): 117-122, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32874045

RESUMO

PURPOSE: The purpose of this study is to evaluate the results of myectomy in inferior oblique overaction cases with a vertical deviation angle of <20 and ≥20 prism diopters (PD) in the primary position. METHODS: The medical records of cases with inferior oblique overaction that underwent inferior oblique myectomy for ≥6 PD hypertropia in the primary position and >+1 inferior oblique overaction were reviewed. Preoperative and postoperative examination findings and success rates were compared of cases with a deviation angle <20 PD (Group 1) and ≥20 PD (Group 2). RESULTS: The mean age of 35 (58%) female and 25 (42%) men cases of Group 1 (n = 60) were 12.8 ± 9.4 years; the mean age of 25 (58%) female and 18 (42%) male cases of Group 2 (n = 43) were 14.8 years (P = 0.340). The near hypertropia was decreased from 11 to 0.5 PD in Group 1, from 22.1 to 5.1 PD in Group 2 cases (P < 0.001). The distance hypertropia was decreased from 11.3 to 0.5 PD in Group 1 and from 23.3 to 6.1 PD in Group 2 cases (P < 0.001). The mean degree of hypertropia at near and distance was statistically significantly higher both pre- and post-operatively in Group 2 than in Group 1 (P < 0.001), and improved statistically significantly with the initial surgery in both groups (P < 0.001). The rate of the presence of stereopsis of ≥3000 s/arc and fusion, the main criteria of binocular vision (BOV), was not statistically significantly different between the Groups before (P = 0.577) and after the surgery (P = 0.678), but the presence of BOV significantly increased both in Group 1 (P < 0.001) and Group 2 (P = 0.004) postoperatively. The number of cases with surgical success was 57 (95%) and 25 (58%), respectively, in Groups 1 and 2 (P < 0.001). CONCLUSIONS: Myectomy is an effective surgical procedure that can be easily and quickly performed in inferior oblique overaction cases and has high success rates in cases with a small-to-moderate angle of deviation.


Assuntos
Transtornos da Motilidade Ocular/cirurgia , Músculos Oculomotores/cirurgia , Estrabismo/cirurgia , Adolescente , Adulto , Anestesia Geral , Criança , Pré-Escolar , Percepção de Profundidade/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Oftalmológicos/métodos , Estudos Retrospectivos , Resultado do Tratamento , Visão Binocular/fisiologia , Adulto Jovem
5.
Proc Natl Acad Sci U S A ; 117(26): 14873-14882, 2020 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-32532920

RESUMO

Arguably the most foundational principle in perception research is that our experience of the world goes beyond the retinal image; we perceive the distal environment itself, not the proximal stimulation it causes. Shape may be the paradigm case of such "unconscious inference": When a coin is rotated in depth, we infer the circular object it truly is, discarding the perspectival ellipse projected on our eyes. But is this really the fate of such perspectival shapes? Or does a tilted coin retain an elliptical appearance even when we know it's circular? This question has generated heated debate from Locke and Hume to the present; but whereas extant arguments rely primarily on introspection, this problem is also open to empirical test. If tilted coins bear a representational similarity to elliptical objects, then a circular coin should, when rotated, impair search for a distal ellipse. Here, nine experiments demonstrate that this is so, suggesting that perspectival shapes persist in the mind far longer than traditionally assumed. Subjects saw search arrays of three-dimensional "coins," and simply had to locate a distally elliptical coin. Surprisingly, rotated circular coins slowed search for elliptical targets, even when subjects clearly knew the rotated coins were circular. This pattern arose with static and dynamic cues, couldn't be explained by strategic responding or unfamiliarity, generalized across shape classes, and occurred even with sustained viewing. Finally, these effects extended beyond artificial displays to real-world objects viewed in naturalistic, full-cue conditions. We conclude that objects have a remarkably persistent dual character: their objective shape "out there," and their perspectival shape "from here."


Assuntos
Percepção de Profundidade/fisiologia , Percepção de Forma/fisiologia , Sinais (Psicologia) , Humanos , Filosofia , Rotação
6.
J Neurosci ; 40(28): 5465-5470, 2020 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-32487694

RESUMO

Each of our eyes sees a slightly different view of the physical world. Disparity is the small difference in position of features in the retinal images; stereopsis is the percept of depth from disparity. A distance between corresponding features in the retinal images of the two eyes smaller than the "upper disparity limit" yields a percept of depth; distances greater than this limit cause the two unfused monocular features to appear flattened into the fixation plane. This behavioral disparity limit is consistent with neurophysiological estimates of the largest disparity scale in primate, allowing us to relate physiological limits on plausible binocular interactions to separation between retinal locations. Here we test the hypothesis that this upper disparity limit predicts the presence of coarse stereopsis in humans with macular degeneration (MD), which affects the central retina but typically spares the periphery. The pattern of vision loss can be highly asymmetric, such that an intact location in one eye has a corresponding point in the other eye that lies within affected retina. Nevertheless, some individuals with MD have coarse stereopsis that is useful for eye-hand coordination. Our results show that individuals with MD (n = 25, male and female) have coarse stereopsis when the distance between intact retinal locations is less than the behavioral and physiological upper disparity limit at the corresponding eccentricity. Furthermore, for those without stereopsis, we can predict whether they can achieve stereopsis by using alternate retinal loci at further eccentricities whose separation is below the upper disparity limit.SIGNIFICANCE STATEMENT We show that the largest separation between features in the two eyes that yields a percept of depth in humans is related to the largest disparity scale in macaque medial temporal area and to the estimated size of the receptive fields in human depth-sensitive cortical regions. This upper disparity limit also predicts whether individuals with retinal damage due to macular degeneration will have stereopsis. Individuals have stereopsis when the separation between intact retinal locations in the two eyes is smaller than the upper disparity limit measured behaviorally. Our results indicate the importance of the behavioral upper disparity limit as a predictor for stereopsis in populations with retinal damage.


Assuntos
Percepção de Profundidade/fisiologia , Degeneração Macular/fisiopatologia , Retina/fisiopatologia , Disparidade Visual/fisiologia , Acuidade Visual/fisiologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa
7.
PLoS Comput Biol ; 16(5): e1007614, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32421716

RESUMO

For stimuli near perceptual threshold, the trial-by-trial activity of single neurons in many sensory areas is correlated with the animal's perceptual report. This phenomenon has often been attributed to feedforward readout of the neural activity by the downstream decision-making circuits. The interpretation of choice-correlated activity is quite ambiguous, but its meaning can be better understood in the light of population-wide correlations among sensory neurons. Using a statistical nonlinear dimensionality reduction technique on single-trial ensemble recordings from the middle temporal (MT) area during perceptual-decision-making, we extracted low-dimensional latent factors that captured the population-wide fluctuations. We dissected the particular contributions of sensory-driven versus choice-correlated activity in the low-dimensional population code. We found that the latent factors strongly encoded the direction of the stimulus in single dimension with a temporal signature similar to that of single MT neurons. If the downstream circuit were optimally utilizing this information, choice-correlated signals should be aligned with this stimulus encoding dimension. Surprisingly, we found that a large component of the choice information resides in the subspace orthogonal to the stimulus representation inconsistent with the optimal readout view. This misaligned choice information allows the feedforward sensory information to coexist with the decision-making process. The time course of these signals suggest that this misaligned contribution likely is feedback from the downstream areas. We hypothesize that this non-corrupting choice-correlated feedback might be related to learning or reinforcing sensory-motor relations in the sensory population.


Assuntos
Comportamento de Escolha/fisiologia , Tomada de Decisões/fisiologia , Retroalimentação Sensorial/fisiologia , Animais , Córtex Cerebral , Percepção de Profundidade/fisiologia , Feminino , Macaca mulatta , Masculino , Modelos Teóricos , Estimulação Luminosa/métodos , Células Receptoras Sensoriais , Lobo Temporal/fisiologia , Percepção Visual/fisiologia
8.
Strabismus ; 28(1): 7-12, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32301677

RESUMO

Objective: Acute acquired concomitant esotropia (AACE) is a distinct subtype of esotropia. The purpose of this retrospective study was to describe the clinical characteristics and discuss the diagnostic and therapeutic management, and evaluate the effect of prism treatment.Methods: The records of 30 patients who presented with acute-onset diplopia at the General Hospital of Central Theater Command from August 2015 to November 2018 were reviewed. All patients underwent a complete medical history, ophthalmological and orthoptic examinations, and brain and orbital imaging. The patients were followed up between 2 and 8 months (mean 3.9 ± 1.2). Angle of strabismus, refractive error, stereopsis, and results of treatment with prisms were analyzed. Level of stereopsis was assessed before and after prismatic correction. Patient satisfaction was assessed with a telephone follow-up survey.Results: The mean age of the 30 patients was 29.7 ± 10.3 years (range 14-52). All patients complained about uncrossed diplopia, only at distance. The esophoria was concomitant in all cases ranging from 12 to 60 prism diopters (PD) at distance (mean 35.80 ± 14.17) and from 10 to 46 PD at near (mean 26.23 ± 11.46) (t = 6.51, P <.001). Cycloplegic spherical-equivalent refraction averaged -5.25 ± 1.67 D (range -0.50 to -8.13), 28 patients were myopic and 2 were emmetropic, all did not wear glasses for near work. All patients received brain and orbital computed tomography scans and magnetic resonance imaging and, in some cases, neurological examinations were performed. All of these examinations were normal. In 27 out of 30 patients treated with prisms, the diplopia resolved, whereas three patients were not satisfied with prismatic correction and underwent surgery. With prisms the esophoria was concomitant, ranging from 6 to 23 PD at distance fixation and from 4 to 18 PD at near fixation. Out of 30 patients, 23 patients were satisfied, 3 patients were not satisfied because their vision remained uncomfortable and 4 patients had an intermediate score.Conclusion: AACE was characterized by a sudden onset of concomitant non-accommodative esotropia with diplopia or visual confusion. In most cases, prismatic correction had a favorable effect with a resolution of diplopia. It offers a good treatment alternative in the early stage, when the angle of strabismus is unstable and surgery is not without risk.


Assuntos
Diplopia/terapia , Esotropia/terapia , Óculos , Transtornos da Visão/terapia , Doença Aguda , Adolescente , Adulto , Percepção de Profundidade/fisiologia , Diplopia/fisiopatologia , Esotropia/fisiopatologia , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Estudos Retrospectivos , Transtornos da Visão/fisiopatologia , Testes Visuais , Acuidade Visual/fisiologia , Adulto Jovem
9.
J Vis ; 20(3): 9, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32232374

RESUMO

Our visual system uses the disparity between the images received by the two eyes to judge three-dimensional distance to surfaces. We can measure this ability by having subjects discriminate the disparity of rendered surfaces. We wanted to know the basis of the individual differences in this ability. We tested 53 adults with normal vision using a relative disparity detection task. Targets were wedge-shaped surfaces formed from random dots. These were presented in either crossed or uncrossed disparity relative to a random dot background. The threshold disparity ranged from 24 arc seconds in the most-able subject to 275 arc seconds in the least-able subject. There was a small advantage for detecting crossed-disparity targets. We used the noise-masking paradigm to partition subject performance into two factors. These were the subject's equivalent internal noise and their processing efficiency. The parameters were estimated by fitting the linear amplifier model. We found both factors contributed to the individual differences in stereoacuity. Within subjects, those showing an advantage for one disparity direction had enhanced efficiency for that direction. Some subjects had a higher equivalent internal noise for one direction that was balanced out by an increased efficiency. Our approach provides a more thorough account of the stereo-ability of our subjects compared with measuring thresholds alone. We present a normative set of results that can be compared with clinical populations.


Assuntos
Ruído , Mascaramento Perceptivo/fisiologia , Disparidade Visual/fisiologia , Visão Binocular/fisiologia , Adulto , Idoso , Percepção de Profundidade/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Visão Ocular/fisiologia , Acuidade Visual/fisiologia , Adulto Jovem
10.
Semin Ophthalmol ; 35(2): 103-115, 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32228341

RESUMO

Multiple sclerosis (MS) is an acquired demyelinating and inflammatory neurodegenerative disease affecting the central nervous system (CNS). Clinical and subclinical ocular disturbances occur in almost all patients with MS. The objective of this narrative review was to collect and summarize the available scientific information on oculomotor, accommodative and binocular alterations that have been reported in MS. A systematic search strategy with the following descriptors was carried out: multiple sclerosis, ocular motility disorders, internuclear ophthalmoplegia, nystagmus, vergences, fixation, pupil reflex, accommodation and stereopsis. According to the search, some oculomotor alterations were found to be commonly reported in MS, such as alterations in saccades and nystagmus. In contrast, accommodative, vergence and stereopsis alterations have not been comprehensively studied despite their relevance, with only minimal evidence showing a potential negative impact of the disease on these aspects. In conclusion, oculomotor impairment is a common component of disability in MS patients and should be considered when managing this type of patients. More research is still needed to know the real impact of this disease on binocular vision and accommodation.


Assuntos
Acomodação Ocular/fisiologia , Esclerose Múltipla/fisiopatologia , Transtornos da Motilidade Ocular/fisiopatologia , Visão Binocular/fisiologia , Percepção de Profundidade/fisiologia , Humanos , Movimentos Sacádicos/fisiologia
11.
Am J Ophthalmol ; 216: 271-282, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32335058

RESUMO

PURPOSE: To analyze factors affecting depth of focus (DOF) and near vision functionality in eyes implanted with aspheric monofocal intraocular lenses (IOLs). METHODS: This prospective study included 111 eyes of 74 patients that underwent phacoemulsification with monofocal IOL implantation. Ninety-one normal eyes were randomized to receive aberration-free (n = 30) or negative-spherical aberration (SA) IOLs (n = 61). Twenty post-hyperopic femto-LASIK eyes received aberration-free IOLs. Corneal higher-order aberrations (SA, coma, trefoil, and corneal asphericity) for a 6 mm pupil were measured by Scheimpflug tomography. Ray-tracing metrics (visual Strehl optical transfer function [VSOTF], effective range of focus [EROF], sphere shift [SS], EROF-SS), pupil size measurements at far and near, and ocular and corneal SA were obtained using ray-tracing aberrometry. Distance-corrected near visual acuity (DCNVA) and subjective defocus curves up to ±4.0 diopters were evaluated. RESULTS: Multivariable logistic regression found corneal profile and IOL type to be determinants of extended DOF with monofocal IOLs. The aberration-free IOL group showed significantly better DCNVA and higher total SA than the negative-SA group. Post-hyperopic LASIK eyes showed significantly better DCNVA; higher negative SA, coma, and Q value (P < .05), and smaller pupil size (P = .05) than normal eyes implanted with aberration-free IOLs. CONCLUSION: Corneal profile and type of IOL implanted were the most important factors influencing near vision functionality with aspheric monofocal IOLs. Higher positive SA in the aberration-free group potentially led to better DCNVA than the negative-SA group in normal eyes. Hyperprolate corneas had better DOF curves and DCNVA than normal corneas. NOTE: Publication of this article is sponsored by the American Ophthalmological Society.


Assuntos
Percepção de Profundidade/fisiologia , Implante de Lente Intraocular , Lentes Intraoculares , Facoemulsificação , Aberrometria , Idoso , Idoso de 80 Anos ou mais , Aberrações de Frente de Onda da Córnea/fisiopatologia , Feminino , Humanos , Masculino , Estudos Prospectivos , Pseudofacia/fisiopatologia , Refração Ocular/fisiologia , Acuidade Visual/fisiologia
12.
PLoS One ; 15(4): e0230847, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32240209

RESUMO

The number of elements in two stereo-surfaces parallelly overlapped in depth is overestimated compared to that in a single flat surface, even when both have the same number of elements. Using stereoscopic pairs of elements, we evaluated two hypotheses on the overestimation: one that a higher-order process, forming a background surface, increases the number of perceived elements, and the other that the number of elements potentially occluded by the elements on a front surface is taken accounted for. The data from four experiments showed that (a) when binocular disparity between (or among) stereoscopic elements was small, the overestimation occurred for the stimuli we used-a two-surface-overlapping stimulus, where the likelihood for the process to operate was manipulated by changing the averaged luminance of each surface, a volumetric stimulus, where the likelihood for the background surface to be formed would decrease, and a two-non-overlapping-surface stimulus, where the surfaces in depth were not overlapped-, and (b) when binocular disparity was large, the overestimation occurred for the two-surfaces-overlapping stimulus, when the averaged luminance of the two surfaces were the same, and for the volumetric stimulus, but diminished for the surface-overlapping stimulus, when the averaged luminance differed between the surfaces and for the surfaces-non-overlapping stimulus. These results cannot be explained either hypothesis only. We explain the results by postulating that the sensory system processing disparities of elements interferes with that estimating the number of elements, resulting in an overestimation of the elements in a stereo-stimulus, and the disparity range within which the interference occurs may depend on the stimulus depth structure.


Assuntos
Percepção de Profundidade/fisiologia , Disparidade Visual/fisiologia , Visão Binocular/fisiologia , Adulto , Feminino , Humanos , Masculino , Estimulação Luminosa/métodos
13.
Artigo em Inglês | MEDLINE | ID: mdl-32121291

RESUMO

This two-year follow-up assessment was performed on 721 elementary (Grades 2-4) and middle (Grade 1) school students who used, and 62 Grade 4 (Control) students who did not use, E-learning environments from schools in Beijing and Shandong Province, China. Statistical analysis included repeated-measures single-factor and two-factor analyses of variance, and analysis of covariance (ANCOVA). In three assessments over two years, the students' visual acuity, visual field, depth perception, and horary visual acuity were monitored, along with the related differences and developmental changes and the effect of the E-learning environment on these indexes: (1) For the first time, the average values of four indexes of visual function of the students exposure to the E-learning environment were obtained, among which the ratio of poor visual acuity was still high; (2) visual acuity and depth perception in middle school students was poorer than that of elementary school students, but their visual field and horary visual acuity was higher; (3) for the two years, the four indexes of the visual function of students in different grades showed different change trends; and (4) the comparison for G4 and control demonstrated that the frequency of E-learning environment use (6.75 h/week for G4) had no significant effect on the visual acuity and depth perception of the Grades 4 and 5 students in elementary school but had a significant effect on their visual field and horary visual acuity. However, in all of the included students, the E-learning environment use time significantly affected the left and right eye visual acuity in the students, except in G4.


Assuntos
Instrução por Computador/estatística & dados numéricos , Percepção de Profundidade/fisiologia , Instituições Acadêmicas/estatística & dados numéricos , Estudantes/psicologia , Estudantes/estatística & dados numéricos , Transtornos da Visão/diagnóstico , Acuidade Visual/fisiologia , Adolescente , Fatores Etários , Criança , China , Feminino , Humanos , Masculino , Fatores Sexuais
14.
Invest Ophthalmol Vis Sci ; 61(3): 22, 2020 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-32181800

RESUMO

Purpose: To assess interocular delays in amblyopes with stereopsis and to evaluate the relationship between interocular delays and the clinical characteristics. Methods: Twenty amblyopes with stereopsis (median, 400 arcseconds) and 20 controls with normal or corrected to normal visual acuity (≤0 logMAR) and normal stereopsis (≤60 arcseconds) participated. Using a rotating cylinder defined by horizontally moving Gabor patches, we produced a spontaneous Pulfrich phenomenon in order to determine the interocular delays, that is, the interocular phase difference at which ambiguous motion in plane was perceived. Two spatial frequencies-a low (0.95 cycles/degree [c/d]) and a medium (2.85 c/d) spatial frequency-were tested. Results: The absolute interocular delays of the amblyopic group was significantly longer than that of the controls at both low or medium spatial frequencies (P < 0.01). However, the interocular delays was not always in favor of the fellow eye: 35% of the amblyopes (7/20) showed a faster processing of the amblyopic eye than that of the fellow eye at 0.95 c/d and 29.5% (5/17) at 2.85 c/d. No significant correlation was found between interocular delays and the clinical characteristics (e.g., age, treatment history, stereoacuity, and magnitude of anisometropia) in this amblyopic cohort. Conclusions: The interocular delays in amblyopes with stereopsis might result from either a faster or slower processing of the amblyopic eye relative to the fellow eye. This work provides important additional information for binocular processing of dynamic visual stimuli in amblyopia. However, the special role between this form of interocular delays and patients' clinical characteristics remains unknown.


Assuntos
Ambliopia/fisiopatologia , Percepção de Profundidade/fisiologia , Percepção de Movimento/fisiologia , Transtornos da Percepção/fisiopatologia , Adulto , Feminino , Humanos , Masculino , Limiar Sensorial , Visão Binocular/fisiologia , Acuidade Visual/fisiologia , Adulto Jovem
15.
J. optom. (Internet) ; 13(1): 59-68, ene.-mar. 2020. tab, graf
Artigo em Inglês | IBECS | ID: ibc-195309

RESUMO

PURPOSE: To determine the significance of changes and and inter-relationships between three markers of binocular function (aniseikonia, distance and near stereoacuity) following unremarkable LASIK at 3 and 6 months postoperatively. METHODS: All patients underwent LASIK using the Schwind Amaris 750S and the flaps were created using Intralase 150 kHz. Patients were I, monocular myopes II, binocular myopes III, binocular hyperopes IV, binocular astigmats V, anisometropes and VI, matched age and gender control (n = 20 in each group except III where n = 18). Aniseikonia (Awaya test), distance and near stereoacuity (Randot tests) were measured before surgery, and at 3 and 6 months after surgery. At all times data were collected under constant conditions and analyzed using appropriate non-parametric statistical tests. RESULTS: The following statistically significant changes were found after applying the Bonferroni correction (p ≤ 0.001); aniseikonia reduced (groups I, III, IV, V), stereoacuity improved at distance (groups I, III-V) and near (groups I, V). Inter-group differences in aniseikonia distance and near stereoacuity were significant preoperatively, but not postoperatively. In groups I, IV and V, the changes in aniseikonia and stereoacuity (near and distance) were significantly correlated with the preoperative value. Aniseikonia was significantly correlated with distance and near stereoacuity preoperatively but not postoperatively. CONCLUSION: Binocular function improved in all groups after LASIK except in binocular myopes. In general, binocular function was still low compared with the control group at six months postoperatively. It is unclear why binocular function improved in the binocular astigmats


OBJETIVO: Determinar la significancia de cualquier cambio, así como las interrelaciones entre tres marcadores de la función binocular (aniseiconía, estereoagudeza de lejos y de cerca) tras LASIK sin complicaciones a los 3 y 6 meses postoperatorios. MÉTODOS: A todos los pacientes se les realizó cirugía LASIK con el laser Schwind Amaris 750S, creándose los flaps con Intralase 150 kHz. Los grupos de pacientes fueron: I miopes monoculares, II miopes binoculares, III hipermétropes binoculares, IV astígmatas binoculares, V anisométropes y VI controles equivalentes en edad y género (n = 20 en cada grupo, exceptuando III donde n = 18). Se midió la aniseiconía (prueba de Awaya), la estereoagudeza de lejos y de cerca (pruebas Randot) durante el preoperatorio, y a los 3 y 6 meses posteriores a la cirugía. En todo momento se recabaron los datos en condiciones constantes, analizándose los mismos con pruebas estadísticas no paramétricas adecuadas. RESULTADOS: Se encontraron los siguientes cambios estadísticamente significativos tras aplicar la corrección de Bonferroni (p ≤ 0,001); se redujo la aniseiconía (grupos I, III, IV, V), y mejoró la estereoagudeza de lejos (grupos I, III-V) y de cerca (grupos I, V). Las diferencias inter-grupo en cuanto a aniseiconía de lejos y de cerca y la estereoagudeza de cerca fueron significativas en el preoperatorio, pero no en el postoperatorio. En los grupos I, IV y V, los cambios en cuanto a aniseiconía y estereoagudeza (de cerca y de lejos) guardaron una correlación significativa con el valor preoperatorio. La aniseiconía guardó una correlación significativa con la estereoagudeza de lejos y de cerca en el preoperatorio, pero no el postoperatorio. CONCLUSIÓN: La función binocular mejoró en todos los grupos tras la cirugía LASIK, excepto en la miopía binocular. En general, la función binocular fue aún baja al compararse con el grupo control a los seis meses postoperatorios. No queda claro por qué la función binocular mejoró en el astigmatismo binocular


Assuntos
Humanos , Masculino , Feminino , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Aniseiconia/fisiopatologia , Astigmatismo/cirurgia , Percepção de Profundidade/fisiologia , Hiperopia/cirurgia , Ceratomileuse Assistida por Excimer Laser In Situ/métodos , Lasers de Excimer/uso terapêutico , Miopia/cirurgia , Astigmatismo/fisiopatologia , Hiperopia/fisiopatologia , Miopia/fisiopatologia , Estudos Prospectivos , Visão Binocular/fisiologia , Acuidade Visual/fisiologia
16.
J Vis ; 20(2): 1, 2020 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-32040160

RESUMO

Binocular disparity signals allow for the estimation of three-dimensional shape, even in the absence of monocular depth cues. The perception of such disparity-defined form depends, however, on the linkage of multiple disparity measurements over space. Performance limitations in cyclopean tasks thus inform us about errors arising in disparity measurement and difficulties in the linkage of such measurements. We used a cyclopean orientation discrimination task to examine the perception of disparity-defined form. Participants were presented with random-dot sinusoidal modulations in depth and asked to report whether they were clockwise or counter-clockwise rotated. To assess the effect of different noise structures on measurement and linkage processes, task performance was measured in the presence of binocular, random-dot masks, structured as either antiphase depth sinusoids, or as random distributions of dots in depth. For a fixed number of surface dots, the ratio of mask-to-surface dots was varied to obtain thresholds for orientation discrimination. Antiphase masks were found to be more effective than random depth masks, requiring a lower mask-to-surface dot ratio to inhibit performance. For antiphase masks, performance improved with decreased cyclopean frequency, increased disparity amplitude, and/or an increase in the total number of stimulus dots. Although a cross-correlation model of disparity measurement could account for antiphase mask performance, random depth masking effects were consistent with limitations in relative disparity processing. This suggests that performance is noise-limited for antiphase masks and complexity-limited for random masks. We propose that use of differing mask types may prove effective in understanding these distinct forms of impairment.


Assuntos
Orientação Espacial/fisiologia , Mascaramento Perceptivo/fisiologia , Disparidade Visual/fisiologia , Sinais (Psicologia) , Percepção de Profundidade/fisiologia , Percepção de Forma/fisiologia , Humanos , Imageamento Tridimensional , Visão Binocular
17.
Sci Adv ; 6(2): eaay6036, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31934631

RESUMO

The camera-type eyes of vertebrates and cephalopods exhibit remarkable convergence, but it is currently unknown whether the mechanisms for visual information processing in these brains, which exhibit wildly disparate architecture, are also shared. To investigate stereopsis in a cephalopod species, we affixed "anaglyph" glasses to cuttlefish and used a three-dimensional perception paradigm. We show that (i) cuttlefish have also evolved stereopsis (i.e., the ability to extract depth information from the disparity between left and right visual fields); (ii) when stereopsis information is intact, the time and distance covered before striking at a target are shorter; (iii) stereopsis in cuttlefish works differently to vertebrates, as cuttlefish can extract stereopsis cues from anticorrelated stimuli. These findings demonstrate that although there is convergent evolution in depth computation, cuttlefish stereopsis is likely afforded by a different algorithm than in humans, and not just a different implementation.


Assuntos
Decapodiformes/fisiologia , Percepção de Profundidade/fisiologia , Comportamento Predatório/fisiologia , Animais , Movimentos Oculares/fisiologia , Imageamento Tridimensional , Visão Binocular
18.
Am J Ophthalmol ; 214: 14-20, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31926885

RESUMO

PURPOSE: To investigate whether ophthalmologic findings in children with fetal alcohol spectrum disorders (FASD) persist into young adulthood. DESIGN: Prospective cohort study. METHODS: Thirty children (13 female) adopted from eastern Europe to Sweden in the 1990s and diagnosed with FASD by a multidisciplinary team at the median age of 7.9 years were followed up by the same team 13-18 years later. Visual acuity (VA), refraction, stereoacuity, strabismus, ocular media, and fundus were investigated. RESULTS: Median VA in right/left eye (OD/OS) was 20/32/20/32 (0.2/0.2 logMAR) in childhood and 20/22/20/20 (0.05/0.0 logMAR) in adulthood. Median (range) refraction OD/OS was +0.88/+1.25 (-8.75 to +4.75/-9.38 to +5.25) spherical equivalent diopter (D) in childhood and -0.25/-0.25 (-12 to +2.75/-13.25 to +2.63) in adulthood. Astigmatism (≥1 D) was the most common refractive error, in 13 (40%) and 14 (47%) subjects, respectively. Defective stereoacuity (>60 arc second) was noted in 20 subjects (67%) in childhood and 22 (73%) in adulthood. Heterotropia occurred in 12 subjects (40%) in childhood and 13 (43%) in adulthood. Increased tortuosity of the retinal vessels was found in 8 (27%) subjects in childhood vs 11 (37%) in adulthood. Optic nerve hypoplasia was recorded in 3 children and in 4 young adults. CONCLUSIONS: Ophthalmologic findings such as refractive errors, strabismus, and fundus abnormalities are frequent in children with FASD and persist into early adulthood. The facial features characteristic of FAS diminish with age, making a dysmorphology evaluation in adulthood less reliable. An ophthalmologic examination is an important part of the evaluation of FASD in childhood as well as in young adulthood.


Assuntos
Percepção de Profundidade/fisiologia , Transtornos do Espectro Alcoólico Fetal/diagnóstico , Refração Ocular/fisiologia , Erros de Refração/diagnóstico , Estrabismo/diagnóstico , Acuidade Visual/fisiologia , Adulto , Consumo de Bebidas Alcoólicas/efeitos adversos , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Transtornos do Espectro Alcoólico Fetal/etiologia , Transtornos do Espectro Alcoólico Fetal/fisiopatologia , Seguimentos , Idade Gestacional , Humanos , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/diagnóstico , Efeitos Tardios da Exposição Pré-Natal/etiologia , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Estudos Prospectivos , Erros de Refração/fisiopatologia , Doenças Retinianas/diagnóstico , Doenças Retinianas/fisiopatologia , Vasos Retinianos/patologia , Microscopia com Lâmpada de Fenda , Estrabismo/fisiopatologia , Adulto Jovem
19.
Psychon Bull Rev ; 27(2): 341-349, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31950456

RESUMO

Working memory is considered as a cognitive memory buffer for temporarily holding, processing, and manipulating information. Although working memory for verbal and visual information has been studied extensively in the past literature, few studies have systematically investigated how depth information is stored in working memory. Here, we show that the memory performance for detecting changes in stereoscopic depth is low when there is no change in relative depth order, and the performance is reliably better when depth order is changed. Increasing the magnitude of change only improves memory performance when depth order is kept constant. However, if depth order is changed, the performance remains high, even with a small change magnitude. Our findings suggest that relative depth order is a better indicator for working memory performance than absolute metric depth. The memory representation for individual depth is not independent, but inherently relational, revealing a fundamental organizing principle for depth information in the visual system.


Assuntos
Percepção de Profundidade/fisiologia , Memória de Curto Prazo/fisiologia , Percepção Visual/fisiologia , Adulto , Humanos
20.
PLoS One ; 15(1): e0228080, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31971977

RESUMO

Dynamic environments often contain features that change at slightly different times. Here we investigated how sensitivity to these slight timing differences depends on spatial relationships among stimuli. Stimuli comprised bilaterally presented plaid pairs that rotated, or radially expanded and contracted to simulate depth movement. Left and right hemifield stimuli initially moved in the same or opposite directions, then reversed directions at various asynchronies. College students judged whether the direction reversed first on the left or right-a temporal order judgment (TOJ). TOJ thresholds remained similar across conditions that required tracking only one depth plane, or bilaterally synchronized depth planes. However, when stimuli required simultaneously tracking multiple depth planes-counter-phased across hemifields-TOJ thresholds doubled or tripled. This effect depended on perceptual set. Increasing the certainty with which participants simultaneously tracked multiple depth planes reduced TOJ thresholds by 45 percent. Even complete certainty, though, failed to reduce multiple-depth-plane TOJ thresholds to levels obtained with single or bilaterally synchronized depth planes. Overall, the results demonstrate that global depth perception can alter local timing sensitivity. More broadly, the findings reflect a coarse-to-fine spatial influence on how we sense time.


Assuntos
Percepção de Profundidade/fisiologia , Percepção do Tempo/fisiologia , Humanos , Modelos Teóricos , Movimento (Física) , Mascaramento Perceptivo , Estimulação Luminosa , Psicometria , Reprodutibilidade dos Testes , Limiar Sensorial , Fatores de Tempo
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