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PURPOSE: To compare the clinical and aberrometric outcomes obtained with a new diffractive pentafocal intraocular lens (IOL) and a diffractive trifocal IOL. METHODS: Patients bilaterally implanted with the pentafocal Intensity SeeLens IOL (Hanita Lenses) (n = 30) and the trifocal FineVision POD F IOL (PhysIOL) (n = 30) during cataract surgery were studied after 1 month for refraction, visual acuity, defocus curve, contrast sensitivity, Hartmann-Shack aberration, and double-pass aberration. The Quality of Vision (QoV) questionnaire was used to evaluate visual comfort. RESULTS: Distance and near visual acuities were similar with the two IOLs, but distance-corrected intermediate visual acuity was better with the Intensity IOLs (0.03 ± 0.04 vs 0.11 ± 0.04 logMAR in the FineVision eyes, P < .01). The difference between objective and subjective refraction was more myopic for the Intensity IOL (-1.15 vs -0.29 diopters [D]). The defocus curve was flatter with the Intensity IOL. Contrast sensitivity was similar in both IOLs. Hartmann-Shack aberration and double-pass aberration were similar, but the modulation transfer function cut-off value was worse with the Intensity IOL: 11.6 ± 2.7 vs 15.3 ± 4.9 (P < .01). QoV scores were better with the Intensity IOL, in particular for glare, halos, and starburst. CONCLUSIONS: In this comparative series, the pentafocal Intensity IOL provided better intermediate vision and better defocus curve than the FineVision IOL, with comparable distance and near vision. The optical disturbances as reported by the patients were higher with the FineVision IOL. Additional studies will better define the aberration profile obtained with the pentafocal IOL. [J Refract Surg. 2024;40(9):e604-e613.].
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Sensibilidad de Contraste , Implantación de Lentes Intraoculares , Lentes Intraoculares Multifocales , Facoemulsificación , Diseño de Prótesis , Seudofaquia , Refracción Ocular , Agudeza Visual , Humanos , Agudeza Visual/fisiología , Refracción Ocular/fisiología , Sensibilidad de Contraste/fisiología , Femenino , Masculino , Seudofaquia/fisiopatología , Anciano , Persona de Mediana Edad , Encuestas y Cuestionarios , Estudios Prospectivos , Satisfacción del Paciente , Aberrometría , Lentes Intraoculares , Aberración de Frente de Onda Corneal/fisiopatologíaRESUMEN
PURPOSE: To report 12-month visual and refractive outcomes following topography-guided femtosecond laser-assisted laser in situ keratomileusis (LASIK) for myopia and compound myopic astigmatism correction. METHODS: This prospective, single-center observational study was conducted in an outpatient clinical practice at the Stanford University Byers Eye Institute in Palo Alto, California. Uncorrected (UDVA) and corrected (CDVA) distance visual acuity, 5% and 25% contrast sensitivity CDVA, and manifest refraction following topography-guided femtosecond laser-assisted LASIK were assessed. Refractive measurements were used to perform a vector analysis. RESULTS: Sixty eyes of 30 patients (mean age: 32.8 ± 7.0 years; range: 23 to 52 years) undergoing topography-guided LASIK for the correction of myopia and compound myopic astigmatism were analyzed. Mean postoperative UDVA was -0.09 ± 0.10 logarithm of the minimum angle of resolution (logMAR) at 12 months. Mean preoperative CDVA was -0.09 ± 0.09 and -0.13 ± 0.08 logMAR at postoperative 12 months. At 12 months, 26.9% of eyes had gained one or more lines of postoperative UDVA compared to baseline CDVA. Mean pre-operative 5% contrast sensitivity CDVA was 0.68 ± 0.07 and 0.64 ± 0.12 logMAR at 12 months (P = .014) following LASIK. CONCLUSIONS: Topography-guided LASIK for myopia and myopic astigmatism correction provided excellent visual and refractive outcomes that were predictable, precise, and stable up to 12 months postoperatively. [J Refract Surg. 2024;40(9):e595-e603.].
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Astigmatismo , Topografía de la Córnea , Queratomileusis por Láser In Situ , Láseres de Excímeros , Miopía , Refracción Ocular , Cirugía Asistida por Computador , Agudeza Visual , Humanos , Queratomileusis por Láser In Situ/métodos , Agudeza Visual/fisiología , Astigmatismo/cirugía , Astigmatismo/fisiopatología , Estudios Prospectivos , Miopía/cirugía , Miopía/fisiopatología , Refracción Ocular/fisiología , Adulto , Masculino , Femenino , Adulto Joven , Láseres de Excímeros/uso terapéutico , Persona de Mediana Edad , Cirugía Asistida por Computador/métodos , Sensibilidad de Contraste/fisiología , Resultado del Tratamiento , Estudios de SeguimientoRESUMEN
PURPOSE: To compare early visual quality of small incision lenticule extraction (SMILE) versus laser in situ keratomileusis (LASIK) in terms of low contrast acuity. METHODS: A secondary analysis was performed using a harmonized dataset derived from two completed prospective cohort studies on active-duty military service members undergoing either SMILE (n = 37), wavefront-guided (WFG) LASIK (n = 51), or wavefront-optimized (WFO) LASIK (n = 56). Night vision and photopic and mesopic low contrast visual acuity (LCVA) up to 3 months postoperatively were compared between groups. RESULTS: Compared to SMILE-treated eyes, WFG LASIK-treated eyes had significantly better night vision and photopic LCVA at 1 month postoperatively (beta = -0.039, P = .016; beta = -0.043, P = .007, respectively). WFO LASIK-treated eyes had significantly better photopic LCVA at 1 month postoperatively (beta = -0.039, P = .012) but had worse mesopic LCVA at 3 months postoperatively (beta = 0.033, P = .015) versus SMILE-treated eyes. CONCLUSIONS: SMILE and LASIK, on either a WFG or WFO laser platform, yielded excellent outcomes, but LCVA seemed to recover quicker following LASIK compared to SMILE. [J Refract Surg. 2024;40(9):e667-e671.].
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Sensibilidad de Contraste , Sustancia Propia , Queratomileusis por Láser In Situ , Láseres de Excímeros , Miopía , Agudeza Visual , Humanos , Queratomileusis por Láser In Situ/métodos , Agudeza Visual/fisiología , Miopía/cirugía , Miopía/fisiopatología , Estudios Prospectivos , Adulto , Masculino , Láseres de Excímeros/uso terapéutico , Femenino , Sustancia Propia/cirugía , Sensibilidad de Contraste/fisiología , Adulto Joven , Refracción Ocular/fisiología , Cirugía Laser de Córnea/métodos , Visión Nocturna/fisiología , Personal Militar , Resultado del TratamientoRESUMEN
PURPOSE: To assess structural (optical coherence tomography, fundus autofluorescence) and functional (contrast sensitivity and visual field) test results which were used for detecting early retinal changes in patients using oral hydroxychloroquine. METHODS: Patients using oral hydroxychloroquine for at least one year were divided into two groups according to the duration of drug use. Groups 1 and 2 consisted of patients with drug use for more than 5 years and 1-5 years, respectively. The drug-using groups were compared with the control group. The mean retinal nerve fiber layer (RNFL), central macular thickness (CMT), ganglion cell-inner plexiform layer (GC-IPL), static 10-2 visual field, fundus autofluorescence (FAF) imaging, and contrast sensitivity tests were performed and statistically compared between groups. RESULTS: Median and temporal quadrant RNFL thicknesses were found to be statistically significantly lower in the drug groups. In the drug groups, the GC-IPL sectoral and mean thicknesses were found to be statistically lower in all quadrants. Central macular thickness was also found to be similar in all three groups. There was no significant difference between the groups in visual field parameters. Macular FAF images were significantly higher in the drug users, but there was no significant difference between the three groups in foveal FAF images. Contrast sensitivity measurements were significantly lower in the drug groups than in the control group at all spatial frequencies except 6 and 18 cycles/degree. CONCLUSIONS: The combined use of structural and functional tests in patients using hydroxychloroquine provides useful information in detecting early retinal changes.
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Antirreumáticos , Sensibilidad de Contraste , Diagnóstico Precoz , Angiografía con Fluoresceína , Hidroxicloroquina , Mácula Lútea , Enfermedades de la Retina , Células Ganglionares de la Retina , Tomografía de Coherencia Óptica , Campos Visuales , Humanos , Hidroxicloroquina/efectos adversos , Tomografía de Coherencia Óptica/métodos , Femenino , Masculino , Campos Visuales/fisiología , Campos Visuales/efectos de los fármacos , Persona de Mediana Edad , Antirreumáticos/efectos adversos , Enfermedades de la Retina/inducido químicamente , Enfermedades de la Retina/diagnóstico , Mácula Lútea/efectos de los fármacos , Mácula Lútea/patología , Mácula Lútea/diagnóstico por imagen , Células Ganglionares de la Retina/patología , Células Ganglionares de la Retina/efectos de los fármacos , Sensibilidad de Contraste/fisiología , Sensibilidad de Contraste/efectos de los fármacos , Angiografía con Fluoresceína/métodos , Adulto , Fibras Nerviosas/patología , Fibras Nerviosas/efectos de los fármacos , Agudeza Visual , Pruebas del Campo Visual/métodos , AncianoRESUMEN
Purpose: To develop a novel classification of highly myopic eyes using artificial intelligence (AI) and investigate its relationship with contrast sensitivity function (CSF) and fundus features. Methods: We enrolled 616 highly myopic eyes of 616 patients. CSF was measured using the quantitative CSF method. Myopic macular degeneration (MMD) was graded according to the International META-PM Classification. Thickness of the macula and peripapillary retinal nerve fiber layer (p-RNFL) were assessed by fundus photography and optical coherence tomography, respectively. Classification was performed by combining CSF and fundus features with principal component analysis and k-means clustering. Results: With 83.35% total variance explained, highly myopic eyes were classified into four AI categories. The percentages of AI categories 1 to 4 were 14.9%, 37.5%, 36.2%, and 11.4%, respectively. Contrast acuity of the eyes in AI category 1 was the highest, which decreased by half in AI category 2. For AI categories 2 to 4, every increase in category led to a decrease of 0.23 logarithm of the minimum angle of resolution in contrast acuity. Compared with those in AI category 1, eyes in AI category 2 presented a higher percentage of MMD2 and thinner temporal p-RNFL. Eyes in AI categories 3 and 4 presented significantly higher percentage of MMD ≥ 3, thinner nasal macular thickness and p-RNFL (P < 0.05). Multivariate regression showed AI category 4 had higher MMD grades and thinner macular compared with AI category 3. Conclusions: We proposed an AI-based classification of highly myopic eyes with clear relevance to visual function and fundus features. Translational Relevance: This classification helps to discover the early hidden visual deficits of highly myopic patients, becoming a useful tool to evaluate the disease comprehensively.
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Inteligencia Artificial , Sensibilidad de Contraste , Fondo de Ojo , Tomografía de Coherencia Óptica , Humanos , Femenino , Masculino , Persona de Mediana Edad , Tomografía de Coherencia Óptica/métodos , Anciano , Sensibilidad de Contraste/fisiología , Agudeza Visual/fisiología , Adulto , Miopía Degenerativa/fisiopatología , Miopía Degenerativa/diagnóstico por imagen , Miopía Degenerativa/diagnóstico , Miopía Degenerativa/clasificación , Miopía Degenerativa/patología , Degeneración Macular/clasificación , Degeneración Macular/fisiopatología , Degeneración Macular/diagnóstico , Degeneración Macular/patología , Degeneración Macular/diagnóstico por imagen , Mácula Lútea/patología , Mácula Lútea/diagnóstico por imagen , Mácula Lútea/fisiopatología , Fibras Nerviosas/patologíaRESUMEN
The presaccadic preview of a peripheral target enhances the efficiency of its postsaccadic processing, termed the extrafoveal preview effect. Peripheral visual performance-and thus the quality of the preview-varies around the visual field, even at isoeccentric locations: It is better along the horizontal than vertical meridian and along the lower than upper vertical meridian. To investigate whether these polar angle asymmetries influence the preview effect, we asked human participants to preview four tilted gratings at the cardinals, until a central cue indicated which one to saccade to. During the saccade, the target orientation either remained or slightly changed (valid/invalid preview). After saccade landing, participants discriminated the orientation of the (briefly presented) second grating. Stimulus contrast was titrated with adaptive staircases to assess visual performance. Expectedly, valid previews increased participants' postsaccadic contrast sensitivity. This preview benefit, however, was inversely related to polar angle perceptual asymmetries; largest at the upper, and smallest at the horizontal meridian. This finding reveals that the visual system compensates for peripheral asymmetries when integrating information across saccades, by selectively assigning higher weights to the less-well perceived preview information. Our study supports the recent line of evidence showing that perceptual dynamics around saccades vary with eye movement direction.
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Movimientos Sacádicos , Campos Visuales , Percepción Visual , Humanos , Movimientos Sacádicos/fisiología , Adulto , Percepción Visual/fisiología , Femenino , Masculino , Campos Visuales/fisiología , Estimulación Luminosa/métodos , Adulto Joven , Sensibilidad de Contraste/fisiologíaRESUMEN
The extended depth-of-focus AcrySof IQ Vivity intraocular lens technology offers promising features for presbyopia management, evaluated in this research in a 6 months real-world setting. Prospective interventional mono-centric study including 40 patients who underwent elective bilateral phacoemulsification. We performed one pre-operative visit (V0) and one evaluation six months post-operatively (V1), evaluating uncorrected and corrected visual acuity for near (UNVA/CNVA), intermediate (UIVA/CIVA) and far (UDVA/UCVA), slit-lamp evaluation, tomography with static pupillometry, endothelial cell count and contrast sensitivity chart. In order to assess post-operative Quality of Life, we administered the patients McAlinden's Quality of Vision test and Morlock's Patient-Reported Spectacle Independence Questionnaire. We divided eyes in with Toric-IOL and with non-Toric IOL. A total of 36 eyes received non-tonic IOL implantation, whereas 44 eyes received toric IOL implantation. There were no statistically significant disparities observed in visual outcome measures and contrast sensitivity between the toric group and the non-toric group. Furthermore, we assessed the predictive preoperative refractive astigmatism (PPRA) and residual refractive astigmatism (RRA) in both cohorts, and no statistical significance was found between the two cohorts (p = 0.08). Twenty-one (53%) patients reported total independence from their glasses at all distances. The mean difference between the predicted and measured refractive error, as calculated by spherical equivalent, was 0.09 D. AcrySof IQ Vivity is a well-tolerated and effective IOL with optimal refractive target for both distant and intermediate vision, needing slight spherical addition for the best near vision. Great questionnaire-based satisfaction was reported by the patients.
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Implantación de Lentes Intraoculares , Lentes Intraoculares , Calidad de Vida , Agudeza Visual , Humanos , Femenino , Masculino , Implantación de Lentes Intraoculares/métodos , Anciano , Persona de Mediana Edad , Estudios Prospectivos , Facoemulsificación , Resultado del Tratamiento , Sensibilidad de Contraste/fisiología , Presbiopía/cirugía , Presbiopía/fisiopatología , Encuestas y CuestionariosRESUMEN
The lightness of a surface depends not only on the amount of light reflected off, it but also on the context in which it is embedded. Despite a long history of research, neural correlates of context-dependent lightness perception remain a topic of ongoing debate. Here, we seek to expand on the existing literature by measuring functional magnetic resonance imaging (fMRI) responses to lightness variations induced by the context. During the fMRI experiment, we presented 10 participants with a dynamic stimulus in which either the luminance of a disk or its surround is modulated at four different frequencies ranging from 1 to 8 Hz. Behaviorally, when the surround luminance is modulated at low frequencies, participants perceive an illusory change in the lightness of the disk (lightness induction). In contrast, they perceive little or no induction at higher frequencies. Using this frequency dependence and controlling for long-range responses to border contrast and luminance changes, we found that activity in the primary visual cortex (V1) correlates with lightness induction, providing further evidence for the involvement of V1 in the processing of context-dependent lightness.
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Sensibilidad de Contraste , Imagen por Resonancia Magnética , Estimulación Luminosa , Humanos , Imagen por Resonancia Magnética/métodos , Adulto , Masculino , Estimulación Luminosa/métodos , Femenino , Sensibilidad de Contraste/fisiología , Adulto Joven , Corteza Visual Primaria/fisiología , Corteza Visual/fisiología , LuzRESUMEN
Purpose: To determine the acute effect of caffeine intake on the retinal responses as measured with a global-flash multifocal electroretinogram (gfmERG) protocol at different contrast levels. Methods: Twenty-four young adults (age = 23.3 ± 2.4 years) participated in this placebo-controlled, double-masked, balanced crossover study. On two different days, participants orally ingested caffeine (300 mg) or placebo, and retinal responses were recorded 90 minutes later using a gfmERG at three contrast levels (95%, 50%, and 29%). The amplitude response density and peak time of the direct and induced components (direct component [DC] and induced component [IC], respectively) were extracted for five different eccentricities (1.3°, 5.0°, 9.6°, 15.2°, and 21.9°). Axial length, spherical equivalent refraction, habitual caffeine intake, and body weight were considered as continuous covariates. Results: Increased IC amplitude response density was found after caffeine ingestion in comparison to placebo (P = 0.021, Æp2 = 0.23), specifically for the 95% and 50% stimulus contrasts (P = 0.024 and 0.018, respectively). This effect of caffeine on IC amplitude response density was independent of the retinal eccentricity (P = 0.556). Caffeine had no effect on DC amplitude response density or DC and IC peak times. Conclusions: Our results show that oral caffeine intake increases the inner electro-retinal activity in young adults when viewing stimuli of high- (95%) to medium-contrast (50%). Given the increasing evidence that the inner retinal function is involved in the emmetropization process, these results may suggest that caffeine or its derivatives could potentially play a role in the mechanisms involved in eye growth.
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Cafeína , Estudios Cruzados , Electrorretinografía , Humanos , Cafeína/administración & dosificación , Método Doble Ciego , Masculino , Adulto Joven , Femenino , Electrorretinografía/efectos de los fármacos , Administración Oral , Adulto , Retina/efectos de los fármacos , Retina/fisiología , Estimulantes del Sistema Nervioso Central/administración & dosificación , Estimulantes del Sistema Nervioso Central/farmacología , Estimulación Luminosa , Sensibilidad de Contraste/fisiología , Sensibilidad de Contraste/efectos de los fármacosRESUMEN
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.
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Percepción de Profundidad , Implantación de Lentes Intraoculares , Lentes Intraoculares , Diseño de Prótesis , Agudeza Visual , Humanos , Agudeza Visual/fisiología , Implantación de Lentes Intraoculares/métodos , Percepción de Profundidad/fisiología , Femenino , Masculino , Facoemulsificación/métodos , Refracción Ocular/fisiología , Seudofaquia/fisiopatología , Lentes Intraoculares Multifocales , Anciano , Persona de Mediana Edad , Extracción de Catarata/métodos , Sensibilidad de Contraste/fisiología , Satisfacción del PacienteRESUMEN
Recent advances in nonparametric contrast sensitivity function (CSF) estimation have yielded a new tradeoff between accuracy and efficiency not available to classical parametric estimators. An additional advantage of this new framework is the ability to independently tune multiple aspects of the estimator to seek further improvements. Machine learning CSF estimation with Gaussian processes allows for design optimization in the kernel, acquisition function, and underlying task representation, to name a few. This article describes a novel kernel for CSF estimation that is more flexible than a kernel based on strictly functional forms. Despite being more flexible, it can result in a more efficient estimator. Further, trial selection for data acquisition that is generalized beyond pure information gain can also improve estimator quality. Finally, introducing latent variable representations underlying general CSF shapes can enable simultaneous estimation of multiple CSFs, such as from different eyes, eccentricities, or luminances. The conditions under which the new procedures perform better than previous nonparametric estimation procedures are presented and quantified.
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Sensibilidad de Contraste , Sensibilidad de Contraste/fisiología , Humanos , Aprendizaje AutomáticoRESUMEN
Windows provide access to daylight and outdoor views, influencing building design. Various glazing and window shade materials are used to mitigate glare, overheating and privacy issues, and they affect view clarity. Among them, we evaluated the effect of window films, electrochromic (EC) glass, and fabric shades on view clarity. We conducted an experiment with 50 participants using visual tests adapted from clinical vision tests (visual acuity, contrast sensitivity, color sensitivity) and images displayed on a computer monitor in a controlled laboratory. Window films and EC glass tints outperformed fabric shades in visual acuity, contrast sensitivity and view satisfaction with the exception of the darkest EC tint state and dark grey VLT 3% shade for color sensitivity and view satisfaction. The EC tints pose internal reflection issues and fabric shades are preferred for visual privacy. Window films and EC glass hinder participants' blue-green color discrimination while fabric shades also decrease red-yellow color discrimination. Visual acuity predicts view satisfaction and contrast sensitivity is the strongest predictor for visual privacy. Generally, higher visible light transmittance and lower solar reflectance (darker color) enhance human visual performance. The proposed workflow provides an experimental procedure, identifies the primary variables and establishes a predictive framework for assessing view clarity of fenestration.
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Sensibilidad de Contraste , Agudeza Visual , Humanos , Sensibilidad de Contraste/fisiología , Femenino , Agudeza Visual/fisiología , Masculino , Adulto , Percepción de Color/fisiología , Deslumbramiento , Adulto Joven , Pruebas de Visión/métodosRESUMEN
Neon color spreading (NCS) is an illusory color phenomenon that provides a dramatic example of surface completion and filling-in. Numerous studies have varied both spatial and temporal aspects of the neon-generating stimulus to explore variations in the strength of the effect. Here, we take a novel, parametric, low-level psychophysical approach to studying NCS in two experiments. In Experiment 1, we test the ability of both cone-isolating and equiluminant stimuli to generate neon color spreading for both increments and decrements in cone modulations. As expected, sensitivity was low to S(hort-wavelength) cone stimuli due to their poor spatial resolution, but sensitivity was similar for the other color directions. We show that when these differences in detection sensitivity are accounted for, the particular cone type, and the polarity (increment or decrement), make little difference in generating neon color spreading, with NCS visible at about twice detection threshold level in all cases. In Experiment 2, we use L-cone flicker modulations (reddish and greenish excursions around grey) to study sensitivity to NCS as a function of temporal frequency from 0.5 to 8 Hz. After accounting for detectability, the temporal contrast sensitivity functions for NCS are approximately constant or even increase over the studied frequency range. Therefore there is no evidence in this study that the processes underlying NCS are slower than the low-level processes of simple flicker detection. These results point to relatively fast mechanisms, not slow diffusion processes, as the substrate for NCS.
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Percepción de Color , Estimulación Luminosa , Psicofísica , Células Fotorreceptoras Retinianas Conos , Umbral Sensorial , Humanos , Percepción de Color/fisiología , Células Fotorreceptoras Retinianas Conos/fisiología , Umbral Sensorial/fisiología , Estimulación Luminosa/métodos , Adulto , Sensibilidad de Contraste/fisiología , Femenino , Masculino , Ilusiones Ópticas/fisiología , Adulto JovenRESUMEN
Contrast sensitivity (CS), which constrains human vision, decreases from fovea to periphery, from the horizontal to the vertical meridian, and from the lower vertical to the upper vertical meridian. It also depends on spatial frequency (SF), and the contrast sensitivity function (CSF) depicts this relation. To compensate for these visual constraints, we constantly make saccades and foveate on relevant objects in the scene. Already before saccade onset, presaccadic attention shifts to the saccade target and enhances perception. However, it is unknown whether and how it modulates the interplay between CS and SF, and if this effect varies around polar angle meridians. CS enhancement may result from a horizontal or vertical shift of the CSF, increase in bandwidth, or any combination. In addition, presaccadic attention could enhance CS similarly around the visual field, or it could benefit perception more at locations with poorer performance (i.e., vertical meridian). Here, we investigated these possibilities by extracting key attributes of the CSF of human observers. The results reveal that presaccadic attention (1) increases CS across SF, (2) increases the most preferred and the highest discernable SF, and (3) narrows the bandwidth. Therefore, presaccadic attention helps bridge the gap between presaccadic and postsaccadic input by increasing visibility at the saccade target. Counterintuitively, this CS enhancement was more pronounced where perception is better-along the horizontal than the vertical meridian-exacerbating polar angle asymmetries. Our results call for an investigation of the differential neural modulations underlying presaccadic perceptual changes for different saccade directions.
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Atención , Sensibilidad de Contraste , Movimientos Sacádicos , Campos Visuales , Humanos , Atención/fisiología , Movimientos Sacádicos/fisiología , Campos Visuales/fisiología , Sensibilidad de Contraste/fisiología , Femenino , Masculino , Adulto , Adulto Joven , Estimulación Luminosa/métodos , Percepción Visual/fisiologíaRESUMEN
Purpose: To compare the visual quality after wavefront-guided femtosecond LASIK (WFG FS-LASIK) in patients with different levels of preoperative total ocular higher-order aberrations to guide clinical decision-making regarding patient selection and treatment strategies. Methods: This study included 112 right eyes of 112 patients who previously underwent WFG FS-LASIK for correcting myopia and myopic astigmatism. The patients were divided into two groups based on the mean values of preoperative total ocular HOAs (0.30 ± 0.09 µm): HOA ≤ 0.3 and > 0.3 groups. The visual acuity, manifest refraction, corneal Strehl ratio (SR), root mean square (RMS) of corneal and ocular aberrations, and area under the log contrast sensitivity function (AULCSF) of both groups were compared preoperatively and at 1, 3, 6, and 12 months postoperatively. Results: The induced ocular HOAs and coma (Δ = 1 mo - Preop) were significantly lower in the HOAs > 0.3 group than in the HOAs ≤ 0.3 group (ΔHOAs: 0.39 ± 0.19 vs. 0.29 ± 0.18 µm, t = 2.797, P = 0.006; Δ coma: 0.30 ± 0.19 vs. 0.20 ± 0.21 µm, t = 2.542, P = 0.012). In the HOAs > 0.3 group, ΔHOAs were negatively correlated with the preoperative ocular HOAs (r = -0.315, P = 0.019). In the HOAs ≤ 0.3 group, the regression equation for Δ HOAs = 0.098 + 0.053 |SE| (F = 21.756, P < 0.001). In the HOAs > 0.3 group, the regression equation for ΔHOAs = 0.534 - 1.081 HOAs + 0.038|Sphere| (F = 7.954, P = 0.001). The postoperative uncorrected distance visual acuity, spherical equivalent, corneal aberrations, SR and AULCSF of both groups were similar (all P > 0.05). Furthermore, the ocular aberrations were not significantly different between both groups at 3, 6, and 12 months postoperatively (all P > 0.05). In addition, compared with the preoperative period, the AULCSF of both groups were significantly increased in the postoperative period (all P < 0.05). Conclusions: The induced ocular HOAs and coma in HOAs > 0.3 group were lower. However, both groups achieved equivalent and excellent visual quality after WFG FS-LASIK. WFG FS-LASIK may provide significant visual benefits for a wider range of patients.
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Astigmatismo , Aberración de Frente de Onda Corneal , Queratomileusis por Láser In Situ , Miopía , Agudeza Visual , Humanos , Queratomileusis por Láser In Situ/métodos , Femenino , Masculino , Agudeza Visual/fisiología , Adulto , Estudios Retrospectivos , Miopía/cirugía , Miopía/fisiopatología , Aberración de Frente de Onda Corneal/fisiopatología , Astigmatismo/cirugía , Astigmatismo/fisiopatología , Adulto Joven , Refracción Ocular/fisiología , Resultado del Tratamiento , Persona de Mediana Edad , Sensibilidad de Contraste/fisiologíaRESUMEN
Objectives: It was aimed to compare the clinical results of the mini-monovision technique (MMV) with enhanced monofocal intraocular lens (IOL) and trifocal IOL applications and to evaluate the intereye differences in the MMV group. Materials and Methods: This retrospective observational study evaluated the results of cataract surgeries performed on 48 eyes of 24 patients. Surgeries in Group I were performed for MMV using the RayOne EMV IOL targeting emmetropia in dominant eyes (Group IA) and -0.70 diopter (D) myopia in non-dominant eyes (Group IB), while those in Group II were performed with the AcrySof® IQ PanOptixTM TNFT00 IOL targeting emmetropia. After the surgeries, uncorrected and corrected distance, intermediate, and near distance visual acuities, contrast sensitivity measurements, and defocus curves were determined. Subjective evaluation was made with the National Eye Institute Visual Function Questionnaire (NEI VFQ-25). The groups were compared statistically. Results: Postoperative refraction mean spherical equivalent was -0.25±0.22 D, -0.67±0.33 D, and -0.16±0.31 D in the three groups, respectively. A statistical difference was identified in favor of Group IA for uncorrected distance vision and in favor of Group IB for near vision (p<0.05). There was no difference in bilateral uncorrected visions in Groups I and II (p>0.05). While contrast sensitivity was better in Group I at all spatial frequencies (p<0.05), better vision was achieved in the defocus curve at distance in Group IA and at near in Group IB. In the binocular evaluation, it was seen that Groups I and II had similar results. In the subjective evaluation, NEI-VFQ-25 scores were 94.1±4.2/100 in Group I and 91.5±3.0/100 in Group II at 6 months (p>0.05). Photic complaints were significantly more common in Group II. Conclusion: With the MMV technique, it was observed that enhanced monofocal lenses provided better visual acuity at all distances and less dysphotopsia than trifocal lenses, whereas trifocal lenses were better at providing independence from glasses.
Asunto(s)
Lentes Intraoculares , Lentes Intraoculares Multifocales , Diseño de Prótesis , Refracción Ocular , Agudeza Visual , Humanos , Estudios Retrospectivos , Masculino , Femenino , Agudeza Visual/fisiología , Refracción Ocular/fisiología , Persona de Mediana Edad , Anciano , Facoemulsificación/métodos , Seudofaquia/fisiopatología , Resultado del Tratamiento , Implantación de Lentes Intraoculares/métodos , Estudios de Seguimiento , Sensibilidad de Contraste/fisiología , Visión Binocular/fisiologíaRESUMEN
In this paper, we show that the model we proposed earlier to account for the disparity vergence eye movements (disparity vergence responses, or DVRs) in response to horizontal and vertical disparity steps of white noise visual stimuli also provides an excellent description of the short-latency ocular following responses (OFRs) to broadband stimuli in the visual motion domain. In addition, we reanalyzed the data and applied the model to several earlier studies that used sine-wave gratings (single or a combination of two or three gratings) and white noise stimuli. The model provides a very good account of all of these data. The model postulates that the short-latency eye movements-OFRs and DVRs-can be accounted for by the operation of two factors: an excitatory drive, determined by a weighted sum of contributions of stimulus Fourier components, scaled by a global contrast normalization mechanism. The output of the operation of these two factors is then nonlinearly scaled by the total contrast of the stimulus. Despite different roles of disparity (horizontal and vertical) and motion signals in visual scene analyses, the earliest processing stages of these different signals appear to be very similar.
Asunto(s)
Sensibilidad de Contraste , Movimientos Oculares , Percepción de Movimiento , Estimulación Luminosa , Disparidad Visual , Humanos , Percepción de Movimiento/fisiología , Estimulación Luminosa/métodos , Disparidad Visual/fisiología , Sensibilidad de Contraste/fisiología , Movimientos Oculares/fisiología , Tiempo de Reacción/fisiologíaRESUMEN
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.
Asunto(s)
Percepción de Profundidad , Lentes Intraoculares , Diseño de Prótesis , Refracción Ocular , Visión Binocular , Agudeza Visual , Humanos , Estudios Prospectivos , Agudeza Visual/fisiología , Femenino , Masculino , Visión Binocular/fisiología , Percepción de Profundidad/fisiología , Persona de Mediana Edad , Refracción Ocular/fisiología , Anciano , Estudios de Seguimiento , Implantación de Lentes Intraoculares/métodos , Sensibilidad de Contraste/fisiología , Seudofaquia/fisiopatología , Facoemulsificación , Resultado del TratamientoRESUMEN
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.
Asunto(s)
Sensibilidad de Contraste , Lentes Intraoculares , Satisfacción del Paciente , Seudofaquia , Refracción Ocular , Agudeza Visual , Humanos , Agudeza Visual/fisiología , Femenino , Estudios Prospectivos , Masculino , Persona de Mediana Edad , Refracción Ocular/fisiología , Anciano , Sensibilidad de Contraste/fisiología , Seudofaquia/fisiopatología , Diseño de Prótesis , Facoemulsificación , Implantación de Lentes Intraoculares/métodos , Percepción de Profundidad/fisiología , Visión Binocular/fisiología , Estudios de SeguimientoRESUMEN
BACKGROUND: Individuals at Clinical High Risk (CHR) for psychosis or in their First Episode (FE) of psychosis are in a pivotal time in adolescence or young adulthood when illness can greatly impact their functioning. Finding relevant biomarkers for psychosis in the early stages of illness can contribute to early diagnosis, therapeutic management and prediction of outcome. One such biomarker that has been studied in schizophrenia (SZ) is visual contrast sensitivity (VCS). VCS can be used to differentiate visual information processing function in the magnocellular versus parvocellular visual pathways. Few studies have assessed VCS in early psychosis. METHODS: Participants included CHR (n = 68), FE psychosis (n = 34) and Healthy Comparison (HC) (n = 63). All were clinically assessed and completed a VCS paradigm that involved near threshold luminance and chromatic stimuli. RESULTS: CHR and FE participants had lower VCS in the luminance condition (F[2166] = 3.42, p < 0.05) compared to HC. There was also a significant sex X group interaction (F[5163] = 4.3, p < 0.001) in the luminance condition (F[5163] = 4.3, p < 0.001) as FE males (p < 0.01) and CHR females (p < 0.01) had the greatest deficits compared to male and female HC participants respectively. VCS deficits in the luminance condition were associated with more thought disorder, slower processing speed, worse executive functioning and poor global functioning (r's 0.25-0.50, p < 0.05). CONCLUSION: This study supports the hypothesis that there are deficits in visual information processing, particularly in tasks that emphasize the magnocellular pathway, in patients experiencing early psychosis. VCS therefore has the potential to be used as a biomarker in this population.