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1.
Rev. bras. oftalmol ; 78(4): 242-245, July-Aug. 2019.
Artigo em Inglês | LILACS | ID: biblio-1013681

RESUMO

ABSTRACT Objective: The goal of the study is to analyze the color vision acuity pattern in undergraduates of health courses and to discuss the impact of these diseases in this population. Color deficiencies interfere significantly in the daily routine of professionals in the health area who need to discern different color hues in several situations of their everyday practice. Methods: Sixty-four volunteers, undergraduates of health courses of the Federal University of Alfenas (UNIFAL-MG), participated in the study. One man was excluded because he did not fit the inclusion criteria. Two groups were analyzed according to sex with the Farnsworth Munsell 100-Hue test. Results: There were no significant differences between the eyes and between the groups analyzed. The color vision acuity pattern is between 35 and 40, according to the Total Error Score. The gender issue does not influence the general pattern of the color vision acuity of the health courses undergraduates when those with color vision disorders are removed. Conclusion: Screenings and guidance should be given to undergraduates of health courses so that, aware of their condition of presenting some type of color disorder, they shall make the appropriate decision on which career to follow so that such limitation does not interfere with the quality of their daily life.


RESUMO Objetivo: O objetivo do estudo é analisar a acuidade visual média para cores de estudantes da área de saúde e discutir o impacto das doenças que a afetam nessa população. Deficiências cromáticas interferem de forma significativa no dia a dia de profissionais da área da saúde que necessitam de discernir diferentes matizes em diversas situações de sua prática profissional. Métodos: Participaram da pesquisa 64 voluntários, estudantes de cursos da área de saúde da Universidade Federal de Alfenas, sendo que 1 homem foi excluído por não se adequar aos critérios de inclusão. Dois grupos foram analisados, de acordo com o sexo, com o teste de Farnsworth Munsell 100-Hue. Resultados: Não houve diferenças significativas entre os olhos e entre os grupos analisados. O padrão de visão de cores encontra-se entre 35 e 40, de acordo com a Pontuação do Erro Total. A questão de gênero não influencia no padrão geral da qualidade de visão de cores de estudantes da área de saúde, quando retirados aqueles que apresentam distúrbios da visão cromática. Conclusão: Devem ser realizadas triagens e orientação para estudantes de cursos da área de saúde para que, cientes da sua condição de apresentar algum tipo de distúrbio cromático, possam tomar a decisão adequada sobre qual carreira seguir para que tal limitação não interfira na qualidade de sua vida diária.


Assuntos
Humanos , Masculino , Feminino , Estudantes de Ciências da Saúde , Defeitos da Visão Cromática/diagnóstico , Defeitos da Visão Cromática/epidemiologia , Pessoal de Saúde , Testes de Percepção de Cores/métodos , Competência Profissional , Qualidade de Vida , Escolas para Profissionais de Saúde , Acuidade Visual , Seleção Visual , Defeitos da Visão Cromática/psicologia , Diagnóstico por Computador/métodos , Percepção de Cores/fisiologia , Visão de Cores/fisiologia
2.
BMC Ophthalmol ; 19(1): 56, 2019 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-30786855

RESUMO

BACKGROUND: Cataract patients were always excluded from studies on ageing of colour vision; thus, effect of age-related cataracts on deterioration of colour perception has not been analysed. In present study, impacts of age-related cataracts on colour discrimination, postoperative recovery and related spectra were investigated. METHODS: In this cohort study, thirty age-related cataract patients scheduled for binocular surgery and 30 elderly volunteers were enrolled. Colour discrimination under photopic (1000 lx) and mesopic (40 lx) conditions was evaluated with Farnsworth-Munsell 100-hue test. The total error score (TES) and partial error score (PES) were calculated. RESULTS: Preoperatively, the TES in the patient group was 129.7 ± 59.5 at 1000 lx and 194.6 ± 74.5 at 40 lx, exhibiting worse discrimination than the volunteer group (TES1000lux = 71.5 ± 37.5 and TES40lux = 113.1 ± 38.8, p ≤ 0.001). Inferior perception were detected in the yellow to green-yellow (Y-GY), green-yellow to green (GY-G), green to blue-green (G-BG) and blue-green to blue (BG-B) colour bands (p ≤ 0.003), corresponding to the 470 nm-580 nm range of the visible light spectrum. Under mesopic conditions, the impact expanded to all colour bands except for yellow-red to yellow (YR-Y). Postoperatively, the TES in the patient group were 80.4 ± 62.4 at 1000 lx and 112.0 ± 85.2 at 40 lx, which were lower than those of the preoperative phase (p ≤ 0.001) but similar to those of the volunteer group (p ≥ 0.505). Postoperative improvement occurred in the Y-GY, GY-G and G-BG colour bands (490 nm to 580 nm) at 1000 lx (p ≤ 0.001) and shifted to the Y-GY, GY-G, G-BG and BG-B colour bands (470 nm to 580 nm) at 40 lx (p ≤ 0.001). Deterioration of hue perception for decrement of illumination was detected in the red to yellow-red (R-YR), Y-GY, G-BG, BG-B, blue to purple-blue (B-PB) and red-purple to red (RP-R) colour bands (450 nm to 500 nm) in the volunteer group (p ≤ 0.002) and the R-YR, G-BG, BG-B, B-PB, PB-P and red-purple to red (RP-R) colour bands (from the short-wavelength end to 500 nm) in the patient group preoperatively (p ≤ 0.001). CONCLUSIONS: Phacoemulsification could effectively rebuild colour perception in patients with age-related cataract. The postoperative benefits were most significant in colour bands corresponding with spectrum from 470 nm to 580 nm.


Assuntos
Catarata/fisiopatologia , Percepção de Cores/fisiologia , Recuperação de Função Fisiológica/fisiologia , Transtornos da Visão/fisiopatologia , Idoso , Catarata/complicações , Estudos de Coortes , Humanos , Implante de Lente Intraocular , Visão Mesópica/fisiologia , Pessoa de Meia-Idade , Facoemulsificação , Período Pós-Operatório , Transtornos da Visão/etiologia
3.
Rev. bras. oftalmol ; 77(5): 292-295, set.-out. 2018. tab, graf
Artigo em Português | LILACS | ID: biblio-977862

RESUMO

Resumo A toxoplasmose ocular congênita é uma manifestação da infecção pelo parasita Toxoplasma gondii que ocorrer por meio placentário. Essa doença pode provocar importantes sequelas visuais. Este trabalho descreve um estudo de caso que utilizou avaliação psicofísica visual para descrever alterações funcionais decorrentes da toxoplasmose ocular congênita. A avaliação foi realizada em paciente de 30 anos, sexo masculino, residente em São Luís (MA), hígido com histórico da mãe ter apresentado infecção por toxoplasmose no período gestacional. Somente aos 26 anos foi feita uma avaliação médica detalhada que descreveu lesão na fóvea do olho direito. Na avaliação clínica clássica e na avaliação psicofísica visual, o paciente apresentou visão normal para o olho esquerdo. O olho direito apresentou baixa acuidade visual (valor decimal: 0,028), campo visual com escotomas localizados até 20º de ângulo visual e alteração da visão de cor. O estudo fornece informações médicas seguras e relevantes para o diagnóstico de toxoplasmose ocular congênita utilizando testes eficazes, de baixo custo e boa portabilidade, possibilitando uma alternativa de diagnóstico funcional para ser aplicada em locais de difícil acesso pelo interior do Brasil.


Abstract Congenital ocular toxoplasmosis is a manifestation of infection by the parasite Toxoplasma gondii that occurs through the placenta. This disease can lead to important visual sequelae. This paper describes a case report that uses visual psychophysics for the alterations of congenital ocular toxoplasmosis. The evaluation was performed in a 30-year-old man, a resident of São Luís (MA), with a history of his mother have had toxoplasmosis in the gestational period. Only at 26 years-old he did the detailed medical evaluation that described a lesion the fovea of the right eye. In the classic clinical examination and in visual psychophysical evaluation, the patient presented normal vision for the left eye. The right eye had low visual acuity (decimal value: 0.028), visual field with scotomas up to 20º of visual angle and alteration of color vision. The study offers safe and relevant medical information for the diagnosis of congenital ocular toxoplasmosis using a low-cost evaluation and with good portability, allowing a functional diagnostic alternative to be applied in places difficult to access in the interior of Brazil.


Assuntos
Humanos , Masculino , Adulto , Psicofísica/métodos , Acuidade Visual , Toxoplasmose Ocular/congênito , Toxoplasmose Ocular/diagnóstico , Toxoplasma , Sensibilidades de Contraste/fisiologia , Campos Visuais/fisiologia , Toxoplasmose/transmissão , Complicações Parasitárias na Gravidez , Percepção de Cores/fisiologia , Testes de Percepção de Cores/métodos , Transmissão Vertical de Doenças Infecciosas , Testes de Campo Visual/métodos
4.
Naturwissenschaften ; 105(7-8): 46, 2018 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-29978336

RESUMO

Pollinators search for multiple flora resources throughout their life cycle. Most studies, however, only assess how bees discriminate floral cues in the context of nectar foraging. In the present study, we sought to elucidate whether oil-collecting bees discriminate flowers of Byrsonima variabilis (Malpighiaceae) with petals of different colours when foraging for pollen or oil. As the colour of the standard petal changes during anthesis, we characterised the spectral reflectance patterns of flowers throughout anthesis and modelled chromatic perceptual space to determine how these colour patterns are perceived by bees. Through the quantification of flower pollen in the different phases, we found that the colour of the standard petal is an honest cue of the presence of pollen. Centridine bees preferentially visited flowers with a yellow (bee's green) colour when searching for pollen, but indiscriminately visited flowers with different petal colours when searching for floral oil. We suggest that standard petals, in the species studied and others of the genus, like nectar guides, act as pollen guides, which oil-collecting females use to detect pollen-rich flowers. Moreover, they use different floral clues during foraging for different resources in the same host plant.


Assuntos
Abelhas/fisiologia , Sinais (Psicologia) , Flores/fisiologia , Malpighiaceae/química , Pigmentação , Animais , Percepção de Cores/fisiologia , Feminino , Flores/química , Óleos de Plantas/química , Pólen
5.
Proc Natl Acad Sci U S A ; 115(12): 3168-3173, 2018 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-29507195

RESUMO

Synesthesia is a rare nonpathological phenomenon where stimulation of one sense automatically provokes a secondary perception in another. Hypothesized to result from differences in cortical wiring during development, synesthetes show atypical structural and functional neural connectivity, but the underlying molecular mechanisms are unknown. The trait also appears to be more common among people with autism spectrum disorder and savant abilities. Previous linkage studies searching for shared loci of large effect size across multiple families have had limited success. To address the critical lack of candidate genes, we applied whole-exome sequencing to three families with sound-color (auditory-visual) synesthesia affecting multiple relatives across three or more generations. We identified rare genetic variants that fully cosegregate with synesthesia in each family, uncovering 37 genes of interest. Consistent with reports indicating genetic heterogeneity, no variants were shared across families. Gene ontology analyses highlighted six genes-COL4A1, ITGA2, MYO10, ROBO3, SLC9A6, and SLIT2-associated with axonogenesis and expressed during early childhood when synesthetic associations are formed. These results are consistent with neuroimaging-based hypotheses about the role of hyperconnectivity in the etiology of synesthesia and offer a potential entry point into the neurobiology that organizes our sensory experiences.


Assuntos
Percepção Auditiva/genética , Axônios/fisiologia , Percepção de Cores/genética , Transtornos da Percepção/genética , Percepção Auditiva/fisiologia , Colágeno Tipo IV/genética , Percepção de Cores/fisiologia , Feminino , Expressão Gênica , Variação Genética , Humanos , Integrina alfa2/genética , Peptídeos e Proteínas de Sinalização Intercelular/genética , Masculino , Miosinas/genética , Proteínas do Tecido Nervoso/genética , Linhagem , Transtornos da Percepção/etiologia , Proteínas RGS/genética , Receptores de Superfície Celular , Receptores Imunológicos/genética , Trocadores de Sódio-Hidrogênio/genética , Sinestesia
6.
Invest Ophthalmol Vis Sci ; 59(1): 85-93, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29332120

RESUMO

Purpose: RPE65-associated Leber congenital amaurosis (RPE65-LCA) is a progressive severe retinal dystrophy with early profound dysfunction of rod photoreceptors followed by progressive cone photoreceptor degeneration. We aim to provide detailed information about how cone dysfunction affects color discrimination. Methods: Seven adults (aged 16-21) with RPE65-LCA underwent monocular color discrimination assessment using the Trivector and Ellipse versions of three computerized tests: Cambridge Colour Test (CCT), low vision version of the Cambridge Colour Test (lvvCCT), and the Universal Colour Discrimination Test (UCDT). For comparison, subjects were also tested using the American Optical Hardy Rand Rittler (AO-HRR) plates. Each assessment was repeated three times. Results: The Trivector version of the tests demonstrated that color discrimination along the tritan axis was undetectable in four subjects, and severely reduced in three subjects. These findings were confirmed by the Ellipse version of the tests. Color discrimination along the protan and deutan axes was evident but reduced in six of seven subjects. Four of seven subjects were unable to read any of the HRR plates. Conclusions: The computerized color vision tests adopted in this study provide detailed information about color discrimination in adult RPE65-LCA patients. The condition is associated with severe impairment of color discrimination, particularly along the tritan axis indicating possible early involvement of S-cones, with additional protan and deutan loss to a lesser extent. This psychophysical assessment strategy is likely to be valuable in measuring the impact of therapeutic intervention on cone function.


Assuntos
Percepção de Cores/fisiologia , Amaurose Congênita de Leber/fisiopatologia , Células Fotorreceptoras Retinianas Bastonetes/metabolismo , cis-trans-Isomerases/genética , Adolescente , Testes de Percepção de Cores , Feminino , Variação Genética , Humanos , Amaurose Congênita de Leber/genética , Amaurose Congênita de Leber/metabolismo , Masculino , Adulto Jovem , cis-trans-Isomerases/metabolismo
7.
J Neurosci ; 37(43): 10346-10357, 2017 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-28947573

RESUMO

Attention can facilitate the selection of elementary object features such as color, orientation, or motion. This is referred to as feature-based attention and it is commonly attributed to a modulation of the gain and tuning of feature-selective units in visual cortex. Although gain mechanisms are well characterized, little is known about the cortical processes underlying the sharpening of feature selectivity. Here, we show with high-resolution magnetoencephalography in human observers (men and women) that sharpened selectivity for a particular color arises from feedback processing in the human visual cortex hierarchy. To assess color selectivity, we analyze the response to a color probe that varies in color distance from an attended color target. We find that attention causes an initial gain enhancement in anterior ventral extrastriate cortex that is coarsely selective for the target color and transitions within ∼100 ms into a sharper tuned profile in more posterior ventral occipital cortex. We conclude that attention sharpens selectivity over time by attenuating the response at lower levels of the cortical hierarchy to color values neighboring the target in color space. These observations support computational models proposing that attention tunes feature selectivity in visual cortex through backward-propagating attenuation of units less tuned to the target.SIGNIFICANCE STATEMENT Whether searching for your car, a particular item of clothing, or just obeying traffic lights, in everyday life, we must select items based on color. But how does attention allow us to select a specific color? Here, we use high spatiotemporal resolution neuromagnetic recordings to examine how color selectivity emerges in the human brain. We find that color selectivity evolves as a coarse to fine process from higher to lower levels within the visual cortex hierarchy. Our observations support computational models proposing that feature selectivity increases over time by attenuating the responses of less-selective cells in lower-level brain areas. These data emphasize that color perception involves multiple areas across a hierarchy of regions, interacting with each other in a complex, recursive manner.


Assuntos
Atenção/fisiologia , Percepção de Cores/fisiologia , Retroalimentação Fisiológica/fisiologia , Neurônios/fisiologia , Estimulação Luminosa/métodos , Córtex Visual/fisiologia , Adulto , Mapeamento Encefálico/métodos , Feminino , Humanos , Magnetoencefalografia/métodos , Masculino , Vias Visuais/fisiologia
8.
Ophthalmology ; 124(6): 873-883, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28237426

RESUMO

PURPOSE: Gene therapy (GT) has offered immense hope to individuals who are visually impaired because of RPE65 mutations. Although GT has shown great success in clinical trials enrolling these individuals, evidence for stability and durability of this treatment over time is still unknown. Herein we explored the value of functional magnetic resonance imaging (fMRI) as an objective measure to assess independently the longevity of retinal GT. DESIGN: Individuals with RPE65 mutations who underwent GT in their worse-seeing eye in a phase 1 clinical trial received a second subretinal injection in their contralateral eye in a follow-on clinical trial. Functional magnetic resonance imaging (MRI) was performed longitudinally to assess brain responses of patients with RPE65 mutations after stimulation of their most recently treated eye before and 1 to 3 years after GT. PARTICIPANTS: Seven participants with RPE65 mutations who were part of the follow-on clinical trial gave informed consent to participate in a longitudinal neuroimaging fMRI study. METHODS: All participants underwent fMRI using a 3-Tesla MRI system and a 32-channel head coil. Participants' cortical activations were assessed using a block design paradigm of contrast reversing checkerboard stimuli delivered using an MRI-compatible video system. MAIN OUTCOME MEASURES: The primary parameters being measured in this study were the qualitative and quantitative fMRI cortical activations produced by our population in response to the visual task. RESULTS: Functional MRI results showed minimal or no cortical responses before GT. Significant increase in cortical activation lasting at least 3 years after GT was observed for all participants. Repeated measures analysis showed significant associations between cortical activations and clinical measures such as full-field light sensitivity threshold for white, red, and blue colors; visual field; and pupillary light reflex. CONCLUSIONS: Participants with RPE65 mutations showed intact visual pathways, which became responsive and strengthened after treatment. Functional MRI results independently revealed the efficacy and durability of a 1-time subretinal injection. The fMRI results paralleled those recently reported during the long-term clinical evaluations of the same patients. Results from this study demonstrated that fMRI may play an important role in providing complementary information to patients' ophthalmic clinical evaluation and has usefulness as an outcome measure for future retinal intervention studies.


Assuntos
Terapia Genética , Amaurose Congênita de Leber/terapia , Mutação , Retina/fisiopatologia , Córtex Visual/fisiologia , cis-trans-Isomerases/genética , Adolescente , Adulto , Criança , Percepção de Cores/fisiologia , Dependovirus/genética , Feminino , Seguimentos , Vetores Genéticos , Humanos , Injeções Intraoculares , Amaurose Congênita de Leber/genética , Amaurose Congênita de Leber/fisiopatologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Reflexo Pupilar/fisiologia , Vias Visuais/fisiologia
9.
Child Dev ; 88(1): 83-102, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27241823

RESUMO

Categorical perception is a phenomenon that leads people to group stimuli into categories instead of perceiving their natural continua. This article reviews the literature of two biases connected with categorical perception: categorical color perception and the other-race effect. Although these two phenomena concern distant targets (colors and faces) and imply different biases (one attentional, one mnemonic), they share at least three commonalities. First, they both involve the chunking of continuous dimensions into categories. Second, adult categories are shaped by cultural processes. Third, infants' discrimination performance seems universal and guided by perception. In this article, it is proposed to look for a common developmental mechanism that clarifies the shift from a perceptual to a sociocognitive knowledge of the environment. New perspectives are discussed.


Assuntos
Percepção de Cores/fisiologia , Formação de Conceito/fisiologia , Reconhecimento Facial/fisiologia , Desenvolvimento Humano/fisiologia , Grupos Raciais/psicologia , Percepção Social , Humanos
10.
Nurs Stand ; 31(4): 42-5, 2016 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-27654560

RESUMO

Rationale and key points An objective assessment of the patient's vision is important to assess variation from 'normal' vision in acute and community settings, to establish a baseline before examination and treatment in the emergency department, and to assess any changes during ophthalmic outpatient appointments. ¼ Vision is one of the essential senses that permits people to make sense of the world. ¼ Visual assessment does not only involve measuring central visual acuity, it also involves assessing the consequences of reduced vision. ¼ Assessment of vision in children is crucial to identify issues that might affect vision and visual development, and to optimise lifelong vision. ¼ Untreatable loss of vision is not an inevitable consequence of ageing. ¼ Timely and repeated assessment of vision over life can reduce the incidence of falls, prevent injury and optimise independence. Reflective activity 'How to' articles can help update you practice and ensure it remains evidence based. Apply this article to your practice. Reflect on and write a short account of: 1. How this article might change your practice when assessing people holistically. 2. How you could use this article to educate your colleagues in the assessment of vision.


Assuntos
Competência Clínica , Percepção de Cores/fisiologia , Oftalmologia , Acuidade Visual/fisiologia , Fatores Etários , Visão de Cores , Humanos , Reino Unido , Visão Ocular
11.
Korean J Ophthalmol ; 30(4): 295-301, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27478357

RESUMO

PURPOSE: Our objective was to estimate the maximum color contrast sensitivity (MCCS) thresholds in individuals with chiasma opticum damage. METHODS: The pilot study tested 41 people with pituitary adenoma (PA) and 100 age- and gender-matched controls. Patients were divided into two groups according to PA size, PA ≤1 cm or PA >1 cm. A new MCCS test program was used for color discrimination. RESULTS: The mean total error score (TES) of MCCS was 1.8 in the PA ≤1 cm group (standard deviation [SD], 0.38), 3.5 in the PA >1 cm group (SD, 0.96), and 1.4 in the control group (SD, 0.31; p < 0.001). There was a positive correlation between tumor size and MCCS result (r = 0.648, p < 0.01). In the group that had PA-producing hormones, the TES was 2.5 (SD, 1.09), compared to 4.2 value in the non-functioning PA group of patients that did not have clinically significant hormone excess (SD, 3.16; p < 0.01). In patients with normal visual acuity (VA) or visual field MCCS, the TES was 3.3 (SD, 1.8), while that in patients with VA <0.00 was 4.6 (SD, 2.9). CONCLUSIONS: Results of the MCCS test TES were 1.9 times better in patients with PA ≤1 cm compared to patients with PA >1 cm (p < 0.01). In PA patients with normal VA, the TES was 2.35 times worse than that of healthy persons (p < 0.01).


Assuntos
Adenoma/complicações , Testes de Percepção de Cores/métodos , Sensibilidades de Contraste/fisiologia , Diagnóstico Precoce , Quiasma Óptico , Neoplasias Hipofisárias/complicações , Transtornos da Visão/diagnóstico , Adenoma/diagnóstico , Adolescente , Adulto , Idoso , Percepção de Cores/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Neoplasias Hipofisárias/diagnóstico , Fatores de Tempo , Transtornos da Visão/etiologia , Transtornos da Visão/fisiopatologia , Campos Visuais , Adulto Jovem
12.
BMC Neurosci ; 17(1): 29, 2016 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-27246183

RESUMO

BACKGROUND: The magnitude of multimodal enhancement in the brain is believed to depend on the stimulus intensity and timing. Such an effect has been found in many species, but has not been previously investigated in insects. RESULTS: We investigated the responses to multimodal stimuli consisting of an odour and a colour in the antennal lobe and mushroom body of the moth Manduca sexta. The mushroom body shows enhanced responses for multimodal stimuli consisting of a general flower odour and a blue colour. No such effect was seen for a bergamot odour. The enhancement shows an inverse effectiveness where the responses to weaker multimodal stimuli are amplified more than those to stronger stimuli. Furthermore, the enhancement depends on the precise timing of the two stimulus components. CONCLUSIONS: Insect multimodal processing show both the principle of inverse effectiveness and the existence of an optimal temporal window.


Assuntos
Percepção de Cores/fisiologia , Manduca/fisiologia , Corpos Pedunculados/fisiologia , Percepção Olfatória/fisiologia , Animais , Encéfalo/fisiologia , Cálcio/metabolismo , Feminino , Flores , Masculino , Microscopia , Imagem Óptica , Estimulação Física , Imagens com Corantes Sensíveis à Voltagem
13.
Int Ophthalmol ; 36(6): 829-839, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26968411

RESUMO

To evaluate the color vision of patients with macular diseases after implanting a blue light-filtering intraocular lens (IOL) during vitrectomy. Twenty-seven patients had a blue light-filtering IOL implanted during vitrectomy for macular diseases (macular disease group), and 40 patients without macular disease had the same type of IOL implanted (non-macular disease group). The postoperative best-corrected visual acuity (BCVA) was ≥ 16/20 in all patients. The Farnsworth-Munsell 100-hue test was used to determine total error scores (TES) and mean error scores under photopic and mesopic conditions in both groups. The TES under mesopic conditions was significantly higher than that under photopic conditions in both groups (P < 0.05). However, the TES in the macular disease group was not significantly different from that of the non-macular disease group under both photopic and mesopic conditions. The mean error scores under photopic conditions for hues 11, 14, 16, 17, 18, and 20 (yellowish-red to yellow) were significantly higher in the macular disease group than in the non-macular disease group. The mean error scores for hues 7 and 85 (red) were significantly higher in the non-macular disease group than in the macular disease group. Under mesopic conditions, the mean error scores for hues 30, 60, and 61 were significantly higher in the non-macular disease group than in the macular disease group (P < 0.05). Our results indicate that blue light-filtering IOLs do not alter color discrimination in eyes with macular diseases, and these patients had good postoperative BCVA even under mesopic conditions.


Assuntos
Percepção de Cores/fisiologia , Visão de Cores/fisiologia , Filtração/métodos , Implante de Lente Intraocular , Lentes Intraoculares , Macula Lutea/fisiopatologia , Doenças Retinianas/cirurgia , Vitrectomia/métodos , Idoso , Idoso de 80 Anos ou mais , Sensibilidades de Contraste , Feminino , Humanos , Luz , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Acuidade Visual/fisiologia
14.
Neuropsychologia ; 81: 168-179, 2016 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-26765639

RESUMO

The contributions of the hippocampal formation and adjacent regions of the medial temporal lobe (MTL) to memory are still a matter of debate. It is currently unclear, to what extent discrepancies between previous human lesion studies may have been caused by the choice of distinct patient models of MTL dysfunction, as disorders affecting this region differ in selectivity, laterality and mechanisms of post-lesional compensation. Here, we investigated the performance of three distinct patient groups with lesions to the MTL with a battery of visuo-spatial short-term memory tasks. Thirty-one subjects with either unilateral damage to the MTL (postsurgical lesions following resection of a benign brain tumor, 6 right-sided lesions, 5 left) or bilateral damage (10 post-encephalitic lesions, 10 post-anoxic lesions) performed a series of tasks requiring short-term memory of colors, locations or color-location associations. We have shown previously that performance in the association task critically depends on hippocampal integrity. Patients with postsurgical damage of the MTL showed deficient performance in the association task, but performed normally in color and location tasks. Patients with left-sided lesions were almost as impaired as patients with right-sided lesions. Patients with bilateral post-encephalitic lesions showed comparable damage to MTL sub-regions and performed similarly to patients with postsurgical lesions in the association task. However, post-encephalitic patients showed additional impairments in the non-associative color and location tasks. A strikingly similar pattern of deficits was observed in post-anoxic patients. These results suggest a distinct cerebral organization of associative and non-associative short-term memory that was differentially affected in the three patient groups. Thus, while all patient groups may provide appropriate models of medial temporal lobe dysfunction in associative visuo-spatial short-term memory, additional deficits in non-associative memory tasks likely reflect damage of regions outside the MTL. Importantly, the choice of a patient model in human lesion studies of the MTL significantly influences overall performance patterns in visuo-spatial memory tasks.


Assuntos
Lesões Encefálicas/complicações , Lesões Encefálicas/patologia , Transtornos da Memória/etiologia , Lobo Temporal/patologia , Adulto , Idoso , Lesões Encefálicas/etiologia , Criança , Percepção de Cores/fisiologia , Encefalite por Herpes Simples/complicações , Feminino , Lateralidade Funcional/fisiologia , Humanos , Hipóxia Encefálica/complicações , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Memória de Curto Prazo/fisiologia , Pessoa de Meia-Idade , Testes Neuropsicológicos , Estimulação Luminosa , Índice de Gravidade de Doença , Adulto Jovem
15.
J Neurol Surg A Cent Eur Neurosurg ; 77(2): 118-29, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26444961

RESUMO

PURPOSE: To study visual perception in patients with anterior temporal lobectomy. MATERIALS AND METHODS: We explored some aspects of visual perception and compared the results obtained from 14 control subjects and 14 patients with unilateral anterior temporal lobectomy. Each group included 7 men and 7 women and the same age distribution (patients and controls: age range 27-48 years; mean 37 years). All subjects underwent a conventional ophthalmic examination and were tested for color perception, stereopsis, texture perception, face recognition, and visual illusions. To quantify color, stereoscopic, and texture perception they performed a visuomotor task that required a rapid response to a visual stimulus. Reaction times were measured under several conditions. RESULTS: Mild visual field defects involving the superior quadrant contralateral to the lobectomy were found in five patients; two other patients presented more severe defects. Lobectomized patients showed a lower number of correct trials than normal subjects when performing tasks involving color and texture perception. These patients also had longer reaction times for color, stereoscopic, and texture stimulus detection. Face recognition and perception of illusory images were preserved after unilateral anterior temporal lobectomy. CONCLUSION: Our data indicate that patients with anterior temporal lobectomy show moderate deficits in color, stereo, and texture perception, with no impairment in complex visual stimuli perception.


Assuntos
Percepção de Profundidade/fisiologia , Ilusões/fisiologia , Lobo Temporal/fisiopatologia , Percepção Visual/fisiologia , Adulto , Lobectomia Temporal Anterior , Percepção de Cores/fisiologia , Feminino , Lateralidade Funcional/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade
16.
J Exp Psychol Hum Percept Perform ; 42(5): 648-57, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26594882

RESUMO

Previous research has established that interference from irrelevant-but-salient color distractors occurs when observers search for variable-shape singletons among uniform shapes (singleton detection), but not when they look for a specific shape among mixed shapes (feature search). In the current study, we replicated this finding, and additionally, we introduced a random variation of color. Instead of always presenting the same target and distractor colors, colors were swapped randomly from trial to trial. With random color variation, interference from color distractors was generally stronger, and in particular, it also occurred in feature search mode, suggesting that observers were unable to focus on the relevant dimension (shape) even under the most favorable conditions. A second experiment showed that interference in feature search mode occurred with variable distractor color when target color was fixed, but not with variable target color when distractor color was fixed. Overall, the results question the view that interference in feature search is absent because observers monitor a single feature map (i.e., shape). Rather, random variation of an irrelevant feature induces participants to also monitor the irrelevant feature, which results in interference. Thus, complete distractor rejection is limited to situations with a single distractor feature.


Assuntos
Atenção/fisiologia , Percepção de Cores/fisiologia , Percepção de Forma/fisiologia , Desempenho Psicomotor/fisiologia , Adulto , Humanos , Adulto Jovem
17.
Eye (Lond) ; 30(3): 385-91, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26563653

RESUMO

PURPOSE: To discover what cataract patients see during phacoemulsification and if these light phenomena influence their anxiety levels during surgery. METHODS: In all, 200 patients were interviewed intraoperatively at the Eye Hospital, Petrisberg, Trier, Germany. The quality of the visual experiences was described and if these were pleasant, neutral or unpleasant. Systemic sedation was noted. RESULTS: Among 200 patients (209 eyes): 88 were men (91 eyes; 44%) and 112 were women (118 eyes; 56%). Median age (years): men (71), women (70). Mean operating time was 8 min. 49/209 (23%) were not anxious before and during surgery. 110/209 (52%) were more anxious before than during surgery, 50/209 (24%) were still anxious during surgery, 27/209 (13%) got sedation with midazolam (1-5 mg). Colours in descending order seen: blue, red, pink, yellow, green, purple, turquois, and orange. The most dominant colour combination was red/blue. Structures were seen by 162/209 (78%). Most (61%) intraoperative visual experiences were pleasant, 38% were neutral, and 1% found them transiently unpleasant. Three patients felt blinded by the light of the operating microscope. CONCLUSIONS: The experience of colours and other light phenomena was pleasant for most patients during phacoemulsification under topical anaesthesia. They occur spontaneously when the patient is fixating on the operating light. They are not dependent on the individual or environment. Sedation only in 13%. Direct questioning for visual sensations by the operating surgeon may lead to less need for sedation and lead to less side effects for elderly and multimorbidity people postoperatively. The surgeon can use this knowledge to reassure patients during surgery.


Assuntos
Percepção de Cores/fisiologia , Pacientes/psicologia , Facoemulsificação/psicologia , Fosfenos/fisiologia , Idoso , Ansiedade/psicologia , Sedação Consciente , Feminino , Humanos , Hipnóticos e Sedativos/administração & dosagem , Entrevistas como Assunto , Período Intraoperatório , Implante de Lente Intraocular , Masculino , Midazolam/administração & dosagem
18.
Eye (Lond) ; 30(2): 287-303, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26563659

RESUMO

The purpose of this study was to examine normal vision and eye disease in relation to art. Ophthalmology cannot explain art, but vision is a tool for artists and its normal and abnormal characteristics may influence what an artist can do. The retina codes for contrast, and the impact of this is evident throughout art history from Asian brush painting, to Renaissance chiaroscuro, to Op Art. Art exists, and can portray day or night, only because of the way retina adjusts to light. Color processing is complex, but artists have exploited it to create shimmer (Seurat, Op Art), or to disconnect color from form (fauvists, expressionists, Andy Warhol). It is hazardous to diagnose eye disease from an artist's work, because artists have license to create as they wish. El Greco was not astigmatic; Monet was not myopic; Turner did not have cataracts. But when eye disease is documented, the effects can be analyzed. Color-blind artists limit their palette to ambers and blues, and avoid greens. Dense brown cataracts destroy color distinctions, and Monet's late canvases (before surgery) showed strange and intense uses of color. Degas had failing vision for 40 years, and his pastels grew coarser and coarser. He may have continued working because his blurred vision smoothed over the rough work. This paper can barely touch upon the complexity of either vision or art. However, it demonstrates some ways in which understanding vision and eye disease give insight into art, and thereby an appreciation of both art and ophthalmology.


Assuntos
Oftalmopatias/fisiopatologia , Pinturas , Visão Ocular/fisiologia , Percepção de Cores/fisiologia , Sensibilidades de Contraste/fisiologia , Humanos , Retina/fisiologia
19.
Eye (Lond) ; 29(12): 1545-54, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26272444

RESUMO

PURPOSE: Real-Life Vision Test (RLVT) is a newly developed performance-based measures of functional vision. This present study is designed to determine whether it could be a meaningful assessment for cataract surgery outcomes evaluation. PATIENTS AND METHODS: Age-related cataract patients (56) who scheduled for bilateral cataract surgery and 44 age-matched controls were evaluated by four types of measurements: (1) demographic, medical, cognitive and depressive evaluation, and the reaction time testing; (2) clinical measures (visual acuity, contrast sensitivity, stereopsis, and color perception); (3) the 25-item National Eye Institute's Visual Functioning Questionnaire (NEI-VFQ); (4) the RLVT. Spearman's coefficients and multiple regression analysis were conducted to investigate the relationship among RLVT, clinical measures, and self-report assessment of visual function. RESULTS: The results of RLVT, clinical measures, and NEI-VFQ total scores were improved significantly after cataract surgery. There were no differences between control subjects and post-surgery patients with respect to NEI-VFQ-25 total scores, self-rating depression scale scores and three tasks of RLVT. Change of RLVT was significantly associated with the change of clinical measures in the cataract group. Multiple regression analysis demonstrated that change of distance, intermediate, and near visual acuity, and binocular contrast sensitivity were significant predictors of improvements of RLVT. CONCLUSIONS: Cataract surgery could improve real-world visual ability effectively for cataract patients. Our study highlights the potential usefulness of RLVT as an adjunct to the current outcomes evaluation system for cataract surgery. The use of RLVT combined with clinical and self-survey methods may be the comprehensive strategy to manifest the impact of cataract surgery on patients' overall vision-related quality of life.


Assuntos
Catarata/fisiopatologia , Facoemulsificação , Pseudofacia/fisiopatologia , Qualidade de Vida , Percepção Visual/fisiologia , Idoso , Idoso de 80 Anos ou mais , Percepção de Cores/fisiologia , Sensibilidades de Contraste/fisiologia , Percepção de Profundidade/fisiologia , Feminino , Humanos , Implante de Lente Intraocular , Masculino , Perfil de Impacto da Doença , Inquéritos e Questionários , Testes Visuais/métodos , Acuidade Visual/fisiologia
20.
J Cataract Refract Surg ; 41(6): 1217-23, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26096521

RESUMO

PURPOSE: To compare contrast acuity at different illumination levels, color vision, and the subjective visual impression in patients after bilateral cataract surgery with mixed implantation of a yellow-tinted intraocular lens (IOL) and an orange-tinted IOL. SETTING: Department of Ophthalmology, Hietzing Hospital, Vienna, Austria. DESIGN: Prospective case series. METHODS: Consecutive patients with age-related cataract had standardized small-incision cataract surgery with IOL implantation in the capsular bag. Patients were randomly assigned to receive a yellow Polylens Y30 in 1 eye and an Orange Series model PC 440Y in the contralateral eye. The main outcome measures were contrast acuity, color vision, and subjective visual impression. Contrast acuity was measured at illumination levels of 5.0 lux and 0.5 lux and contrast levels of 50.0%, 25.0%, and 12.5%. Color vision was assessed using the Heidelberg-multicolor anomaloscope, and the subjective visual impression was evaluated using a questionnaire. RESULTS: This study included 64 eyes of 32 patients. The intraindividual comparison showed no significant difference in contrast sensitivity at different contrast and illumination levels or in color vision. On questioning, 3 patients reported a difference in subjective color perception between the 2 IOL types. CONCLUSION: There were no differences in contrast sensitivity or color vision between yellow-tinted IOLs and orange-tinted IOLs. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.


Assuntos
Percepção de Cores/fisiologia , Sensibilidades de Contraste/fisiologia , Filtração , Implante de Lente Intraocular , Lentes Intraoculares , Luz , Facoemulsificação , Idoso , Idoso de 80 Anos ou mais , Visão de Cores/fisiologia , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Desenho de Prótese , Inquéritos e Questionários , Acuidade Visual/fisiologia
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