991 resultados para Vision disorders.
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Pós-graduação em Bases Gerais da Cirurgia - FMB
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Purpose: To determine the scientific evidence about the prevalence of accommodative and nonstrabismic binocular anomalies. Methods: We carried out a systematic review of studies published between 1986 and 2009, analysing the MEDLINE, CINAHL, FRANCIS and PsycINFO databases. We considered admitting those papers related to prevalence in paediatric and adult populations. We identified 660 articles and 10 papers met the inclusion criteria. Results: There is a wide range of prevalence, particularly for accommodative insufficiency (2 %-61.7 %) and convergence insufficiency (2.25 %-33 %). More studies are available for children (7) compared with adults (3). Most of studies examine clinical population (5 studies) with 3 assessed at schools and 1 at University with samples that vary from 65 to 2048 patients. There is great variability regarding the number of diagnostic signs ranging from 1 to 5 clinical signs. We found a relation between the number of clinical signs used and prevalence values for convergence insufficiency although this relationship cannot be confirmed for other conditions. Conclusion: There is a lack of proper epidemiological studies about the prevalence of accommodative and nonstrabismic binocular anomalies. Studies reviewed examine consecutive or selected patients in clinical settings and schools but in any case they are randomized and representative of their populations with no data for general population. The wide discrepancies in prevalence figures are due to both sample population and the lack of uniformity in diagnostic criteria so that it makes difficult to compile results. Biases and limitations of reports determine that prevalence rates offered are only estimations from selected populations.
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Purpose: To analyze the diagnostic criteria used in the scientific literature published in the past 25 years for accommodative and nonstrabismic binocular dysfunctions and to explore if the epidemiological analysis of diagnostic validity has been used to propose which clinical criteria should be used for diagnostic purposes. Methods: We carried out a systematic review of papers on accommodative and non-strabic binocular disorders published from 1986 to 2012 analysing the MEDLINE, CINAHL, PsycINFO and FRANCIS databases. We admitted original articles about diagnosis of these anomalies in any population. We identified 839 articles and 12 studies were included. The quality of included articles was assessed using the QUADAS-2 tool. Results: The review shows a wide range of clinical signs and cut-off points between authors. Only 3 studies (regarding accommodative anomalies) assessed diagnostic accuracy of clinical signs. Their results suggest using the accommodative amplitude and monocular accommodative facility for diagnosing accommodative insufficiency and a high positive relative accommodation for accommodative excess. The remaining 9 articles did not analyze diagnostic accuracy, assessing a diagnosis with the criteria the authors considered. We also found differences between studies in the way of considering patients’ symptomatology. 3 studies of 12 analyzed, performed a validation of a symptom survey used for convergence insufficiency. Conclusions: Scientific literature reveals differences between authors according to diagnostic criteria for accommodative and nonstrabismic binocular dysfunctions. Diagnostic accuracy studies show that there is only certain evidence for accommodative conditions. For binocular anomalies there is only evidence about a validated questionnaire for convergence insufficiency with no data of diagnostic accuracy.
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Enquadramento: O acesso à saúde ocular em escolares dirige primariamente a prevenção de problemas visuais que dificultem o aprendizado, impossibilitando o desenvolvimento das atividades intelectuais e sociais. Os projetos de promoção da saúde oftalmológica são, para a grande maioria dos alunos, a primeira e rara oportunidade de avaliar a visão. Objetivos: Identificar os tipos de déficit visuais mais comuns nas crianças da região metropolitana do Recife; Identificar as queixas mais frequentes relacionadas a baixa de visão; Realizar campanha preventiva para identificação dos déficits, tendo como referência a Guarnição de Aeronáutica de Recife (GAR). Métodos: Estudo descritivo, transversal, intervencionista e quantitativo. A pesquisa ocorreu nos anos de 2013 e 2014, em uma população de 1500 crianças residentes na cidade de Recife, estado de Pernambuco, Brasil, com idades variando entre 7 e 9 anos, onde obtivemos uma amostra de 490 inscrições para participação no programa. Resultados: No primeiro período, atingimos 98,5% de objetividade, aumentando para 99,3% no segundo período. Os estudantes realizaram as consultas maioritariamente pela manhã (58,7%), em escola particular (81,6%) e na sua maioria (57,1%), eram do sexo feminino. A presença de queixas atingiu 78,6% e os sinais e sintomas mais referidos foram: cefaleia (20,8%), prurido ocular (17,6%) e dificuldade de enxergar o quadro (16,8%). Foram identificados e corrigidos 53 casos de erros de refração sendo o astigmatismo (4,74%), o mais diagnosticado, 7 casos de estrabismo e tratados 12 de conjuntivite. Conclusões: Em 2013, 15,1% e em 2014, 14,2% das crianças apresentaram baixa acuidade visual. Astigmatismo e miopia representam 10% dos problemas mais comuns seguidos de hipermetropia e conjuntivite. 84% do total de nossa amostra refere dificuldade de visualização no quadro negro, 68% manifestam cefaleias, 85% dor ocular, 75,5% vermelhidão ocular e 80,3% prurido ocular. Resumindo, os distúrbios visuais são comuns nas crianças, justificando programas de saúde preventiva nas unidades de saúde da FAB. Palavras-chave: Acuidade visual; Criança; Preventiva.
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Federal Transit Administration, Washington, D.C.
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Federal Transit Administration, Washington, D.C.
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Urban Mass Transportation Administration, Washington, D.C.
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National Highway Traffic Safety Administration, Washington, D.C.
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INTRODUCCIÓN: El Edema Macular (EM) es la principal causa de perdida de agudeza visual en pacientes con Oclusión Venosa Retiniana (OVR); luego del tratamiento, algunos pacientes persisten con mala agudeza visual. OBJETIVO: Realizar una Revisión Sistemática de la Literatura (RSL), para identificar la evidencia existente sobre factores tomográficos que predicen el resultado visual en pacientes con EM secundario a OVR. FUENTE DE LA INFORMACIÓN: PUBMED, MEDLINE, EMBASE, LILACS, COCHRANE, literatura gris. SELECCIÓN DE LOS ESTUDIOS: Ensayos Clínicos Controlados (ECC) y estudios observacionales analíticos. EXTRACCIÓN Y SÍNTESIS DE LOS DATOS: Dos investigadores seleccionaron los artículos de forma independiente. Se realizó una síntesis cualitativa de la información siguiendo las recomendaciones de la declaración PRISMA 2009. MEDIDAS Y DESENLACE PRINCIPAL: Grosor Retiniano Central (GRC), integridad de Banda Elipsoide e Integridad de Membrana Limitante Externa (MLE), determinados por SD OCT. El desenlace principal es la Agudeza Visual Mejor Corregida (AVMC) a los 6, 12,18 y/o 24 meses. RESULTADOS: Se identificaron 872 abstract y se incluyeron 8 artículos en el análisis cualitativo. Seis estudios evaluaron el GRC sin encontrar asociación con resultado visual final. Solo 2 estudios evaluaron y encontraron asociación estadísticamente significativa de la integridad de la MLE con el desenlace visual, Kang, H 2012 (r2 0,51 p 0,000), Rodriguez, F 2014 (p< 0,001). La integridad de la BE fue asociada a pronostico visual en 4 de 5 estudios que evaluaron esta variable, con resultados estadísticamente significativos. La AVMC de base también se asocio con desenlace visual en 4 de 5 estudios que la evaluaron. El mejor modelo que predice el resultado funcional según el estudio de Kang, H 2012 fue: Integridad de MLE, integridad de BE y AVMC de base (R2 0,671 p 0,000), a los 12 meses de seguimiento. CONCLUSION: La evidencia actual sugiere que la integridad de la BE y la MLE son predictores del resultados funcional en pacientes con EM secundario a OVR después de 6 o mas meses de seguimiento. Es necesario la realización de estudios controlados para llegar a resultados mas concluyentes.
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A model of the mammalian retina and the behavior of the first layers in the visual cortex is reported. The building blocks are optically programmable logic cells. A model of the retina, similar to the one reported by Dowling (1987) is presented. From the model of the visual cortex obtained, some types of symmetries and asymmetries are possible to be detected
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One of the most challenging problems that must be solved by any theoretical model purporting to explain the competence of the human brain for relational tasks is the one related with the analysis and representation of the internal structure in an extended spatial layout of múltiple objects. In this way, some of the problems are related with specific aims as how can we extract and represent spatial relationships among objects, how can we represent the movement of a selected object and so on. The main objective of this paper is the study of some plausible brain structures that can provide answers in these problems. Moreover, in order to achieve a more concrete knowledge, our study will be focused on the response of the retinal layers for optical information processing and how this information can be processed in the first cortex layers. The model to be reported is just a first trial and some major additions are needed to complete the whole vision process.
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Purpose To investigate the frequency of convergence and accommodation anomalies in an optometric clinical setting in Mashhad, Iran, and to determine tests with highest accuracy in diagnosing these anomalies. Methods From 261 patients who came to the optometric clinics of Mashhad University of Medical Sciences during a month, 83 of them were included in the study based on the inclusion criteria. Near point of convergence (NPC), near and distance heterophoria, monocular and binocular accommodative facility (MAF and BAF, respectively), lag of accommodation, positive and negative fusional vergences (PFV and NFV, respectively), AC/A ratio, relative accommodation, and amplitude of accommodation (AA) were measured to diagnose the convergence and accommodation anomalies. The results were also compared between symptomatic and asymptomatic patients. The accuracy of these tests was explored using sensitivity (S), specificity (Sp), and positive and negative likelihood ratios (LR+, LR−). Results Mean age of the patients was 21.3 ± 3.5 years and 14.5% of them had specific binocular and accommodative symptoms. Convergence and accommodative anomalies were found in 19.3% of the patients; accommodative excess (4.8%) and convergence insufficiency (3.6%) were the most common accommodative and convergence disorders, respectively. Symptomatic patients showed lower values for BAF (p = .003), MAF (p = .001), as well as AA (p = .001) compared with asymptomatic patients. Moreover, BAF (S = 75%, Sp = 62%) and MAF (S = 62%, Sp = 89%) were the most accurate tests for detecting accommodative and convergence disorders in terms of both sensitivity and specificity. Conclusions Convergence and accommodative anomalies are the most common binocular disorders in optometric patients. Including tests of monocular and binocular accommodative facility in routine eye examinations as accurate tests to diagnose these anomalies requires further investigation.
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There is substantial evidence of the decreased functional capacity, especially everyday functioning, of people with psychotic disorder in clinical settings, but little research about it in the general population. The aim of the present study was to provide information on the magnitude of functional capacity problems in persons with psychotic disorder compared with the general population. It estimated the prevalence and severity of limitations in vision, mobility, everyday functioning and quality of life of persons with psychotic disorder in the Finnish population and determined the factors affecting them. This study is based on the Health 2000 Survey, which is a nationally representative survey of 8028 Finns aged 30 and older. The psychotic diagnoses of the participants were assessed in the Psychoses of Finland survey, a substudy of Health 2000. The everyday functioning of people with schizophrenia is studied widely, but one important factor, mobility has been neglected. Persons with schizophrenia and other non-affective psychotic disorders, but not affective psychoses had a significantly increased risk of having both self-reported and test-based mobility limitations as well as weak handgrip strength. Schizophrenia was associated independently with mobility limitations even after controlling for lifestyle-related factors and chronic medical conditions. Another significant factor associated with problems in everyday functioning in participants with schizophrenia was reduced visual acuity. Their vision was examined significantly less often during the five years before the visual acuity measurement than the general population. In general, persons with schizophrenia and other non-affective psychotic disorder had significantly more limitations in everyday functioning, deficits in verbal fluency and in memory than the general population. More severe negative symptoms, depression, older age, verbal memory deficits, worse expressive speech and reduced distance vision were associated with limitations in everyday functioning. Of all the psychotic disorders, schizoaffective disorder was associated with the largest losses of quality of life, and bipolar I disorder with equal or smaller losses than schizophrenia. However, the subjective loss of qualify of life associated with psychotic disorders may be smaller than objective disability, which warrants attention. Depressive symptoms were the most important determinant of poor quality of life in all psychotic disorders. In conclusion, subjects with psychotic disorders need regular somatic health monitoring. Also, health care workers should evaluate the overall quality of life and depression of subjects with psychotic disorders in order to provide them with the basic necessities of life.
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The early detection of developmental disorders is key to child outcome, allowing interventions to be initiated which promote development and improve prognosis. Research on autism spectrum disorder (ASD) suggests that behavioral signs can be observed late in the first year of life. Many of these studies involve extensive frame-by-frame video observation and analysis of a child's natural behavior. Although nonintrusive, these methods are extremely time-intensive and require a high level of observer training; thus, they are burdensome for clinical and large population research purposes. This work is a first milestone in a long-term project on non-invasive early observation of children in order to aid in risk detection and research of neurodevelopmental disorders. We focus on providing low-cost computer vision tools to measure and identify ASD behavioral signs based on components of the Autism Observation Scale for Infants (AOSI). In particular, we develop algorithms to measure responses to general ASD risk assessment tasks and activities outlined by the AOSI which assess visual attention by tracking facial features. We show results, including comparisons with expert and nonexpert clinicians, which demonstrate that the proposed computer vision tools can capture critical behavioral observations and potentially augment the clinician's behavioral observations obtained from real in-clinic assessments.
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The early detection of developmental disorders is key to child outcome, allowing interventions to be initiated that promote development and improve prognosis. Research on autism spectrum disorder (ASD) suggests behavioral markers can be observed late in the first year of life. Many of these studies involved extensive frame-by-frame video observation and analysis of a child's natural behavior. Although non-intrusive, these methods are extremely time-intensive and require a high level of observer training; thus, they are impractical for clinical and large population research purposes. Diagnostic measures for ASD are available for infants but are only accurate when used by specialists experienced in early diagnosis. This work is a first milestone in a long-term multidisciplinary project that aims at helping clinicians and general practitioners accomplish this early detection/measurement task automatically. We focus on providing computer vision tools to measure and identify ASD behavioral markers based on components of the Autism Observation Scale for Infants (AOSI). In particular, we develop algorithms to measure three critical AOSI activities that assess visual attention. We augment these AOSI activities with an additional test that analyzes asymmetrical patterns in unsupported gait. The first set of algorithms involves assessing head motion by tracking facial features, while the gait analysis relies on joint foreground segmentation and 2D body pose estimation in video. We show results that provide insightful knowledge to augment the clinician's behavioral observations obtained from real in-clinic assessments.