Academic literature on the topic 'Binocular vision anomalies'

Computerised diagnostic testing and computerised vision training (VT) have been developed for the orthoptic management of binocular vision (BV) anomalies in clinical practice. Computerised measurement of BV is assumed to assist accurate diagnosis of BV anomalies because variability of testing resulting from subjective judgements of examiners is eliminated by automatic measurements. Computerised VT is thought to be effective in the treatment of BV anomalies because the computer games used for vision training will enhance the patient's motivation. However, these assumptions were lacking scientific support. This thesis reports a range of studies to investigate the computerised programs of diagnostic testing (HTS-BVA) and vision training (HTS-iNet) in comparison with corresponding traditional approaches, respectively. The first study was to investigate inter-session repeatability of computerised testing on BV functions. The study results showed that computerised testing on measuring near horizontal fusional vergence (FV) and accommodative facility (AF) did not present higher inter-session repeatability than corresponding traditional testing. The second study was a pilot study for a future rigorous randomized clinical trial (RCT) investigating effectiveness of computerised VT as a home-based treatment for convergence insufficiency (CI). The study results showed the subjects with CI demonstrated improvement of near point of convergence (NPC), near base-out FV and symptoms associated with CI after an 8-week treatment regime. The third study, following from the first study, was to investigate whether accommodative responses (AR) are affected by the novel accommodative stimuli used in computerised AF testing. The study results showed the AR might be affected by the colours of accommodative targets and the colour filter used. Especially, the data of accommodative demand of 4 dioptres revealed that blue targets presented poorer AR than red targets, and the targets seen with colour filters presented poorer AR than those seen without colour filters. The fourth study, also following from the first study, was to investigate whether a prolonged near vision task affects measurements made relating to the near FV system, thus contributing to the variability of clinical findings. The study results showed statistically significant changes in NPC and near dissociated phoria. In further sub-group analyses, the subjects with an initially poor NPC (n = 9) presented greater changes in the NPC and near dissociated phoria than the subjects with normal poor NPC (n = 25).Overall, the computerised testing did not show more repeatable BV measurements than the traditional testing. Finally, an RCT is needed to determine if the computerised VT is more effective than placebo computerised VT as a home-based treatment for CI.

The importance of good vision for acquiring a sound fundamental base in reading and writing skills, in early years, has implications for scholastic achievement and future prospects in adult life. Where the underlying problems in children, who have difficulties in school, are not related to intellect, the ocular and visual systems need to be examined. This thesis is based on observations of 1153 school-children, aged from 7 to 14 years, who had been found to have problems with reading and writing but had no intellectual impediments to learning. The results have shown that the vast majority 72% of these children demonstrate binocular vision problems that can be treated. Treatment options for convergence insufficiency and convergence excess were trialled. It was found that prismatic correction, reading glasses and muscle exercise therapy were effective. Reading speed and efficiency could be improved to normal levels within a period of four weeks. These findings indicate that there is significant plasticity in the visual systems of the eyes of children and that any dysfunctions should be rapidly treated. The thesis has also shown the basis on which the level of prismatic correction is derived. It is also the first to show a comparison of calibrated reading tests in German and English. The physiological mechanisms in the developing and growing eye may have an influence on other measures. Muscular forces within the eyeball (controlling accommodation) and externally placed (controlling eye movements) may have an influence on the pressure with the eye. Little is known about the normal variations with age in intraocular pressure in children. This study has shown that there is an age-related increase in intraocular pressure that plateaus after age 9 and that there are differences between children with binocular vision problems and controls. Reasons for these differences are discussed and further investigations suggested.

Beaucoup d'adolescents sous-estiment leur inconfort visuel, bien qu'il puisse affecter leur scolarité. La prévalence des troubles visuels chez des participants âgés de quinze à vingt-deux ans a été étudiée et les résultats obtenus ont été comparés à leur niveau scolaireEntre septembre 2012 et avril 2013, quatre cents jeunes gens âgés de quinze à vingt-deux ans ont répondu à un questionnaire relatif à des signes d’asthénopie, suivi d’un examen visuel (réfraction, fonctionnement accommodatif et vision binoculaire), afin de détecter des gênes visuelles dont ils pourraient ne pas être spontanément conscients. Lorsque des problèmes visuels ont été détectés, il a été proposé aux participants de passer un examen ophtalmologique et un bilan orthoptique. Puis, le niveau scolaire de ces quatre cents jeunes a été expertisé. Les participants ont ensuite été revus pour déterminer si le port d'une correction optique adaptée et/ou la prise en charge orthoptique ont permis d'obtenir une amélioration de la performance scolaire.Les résultats indiquent que le score au questionnaire est significatif pour prédire la probabilité d’avoir une faible performance scolaire et d’avoir des troubles visuels, que les anomalies de la réfraction et de l’accommodation ont un réel impact sur la performance scolaire et plus encore, que ce sont les troubles de la vision binoculaire qui sont les plus pénalisants. Surtout, l’absence d’une plainte visuelle spontanément exprimée ne permet pas de conclure à l’absence de problèmes visuels.Une fois la performance scolaire contrôlée par des variables utilisées habituellement pour l’expliquer (e.g. retard scolaire, CSP du chef de famille, sexe, etc.), une partie non négligeable des difficultés scolaires des participants proviennent de problèmes liés à la vision. Par conséquent, un dépistage systématique des troubles visuels chez les adolescents semble nécessaire, d’autant plus s’ils rencontrent des difficultés scolaires. Par ailleurs, le questionnaire mis en place dans l’anamnèse semble être un outil efficace dans la détection de la présence de troubles et mériterait d’être validé sur un plus large échantillon
Many students understate their visual discomfort, although it may have an educational impact. We studied the prevalence of visual disorders among students and compared these results to their academic level.Between September 2012 and April 2013, four hundred students between fifteen and twenty two years of age responded to a questionnaire followed by a visual screening (refraction and binocular vision) in order to detect any visual discomfort that they might be unaware of. When visual problems were detected, the participants were asked to have an ophthalmology and orthoptic assessment. Then the participants’ academic performance was appraised and subjects were reviewed to determine whether wearing the appropriate optical correction or taking orthoptic care have improved their grades.The results indicate that the questionnaire score is very significant to predict the probability of having academic difficulties or vision problems, that ametropia and accommodation anomalies increase academic difficulties and that binocular vision disorders are even more disadvantageous. Moreover, not spontaneously expressing visual discomfort doesn’t mean that there are no visual defects.Once controlled by variables commonly used to explain academic difficulties (e.g. academic delay, occupational category, gender, etc.) a significant proportion of participants’ academic difficulties are related to vision anomalies. Therefore, vision screening among adolescents appears to be necessary, especially if there are academic difficulties. In addition, the questionnaire used in case history seems to be an effective tool to detect vision anomalies and should be validated with a larger sample

RESUMO - Esta tese pretende ser um contributo para o estudo das anomalias da função visual e da sua influência no desempenho da leitura. Apresentava como objetivos: (1) Identificar a prevalência de anomalias da função visual, (2) Caracterizar o desempenho da leitura em crianças com e sem anomalias da função visual, (3) Identificar de que modo as anomalias da função visual influenciam o desempenho da leitura e (4) Identificar o impacto das variáveis que determinam o desempenho da leitura. Foi recolhida uma amostra de conveniência com 672 crianças do 1º ciclo do ensino básico de 11 Escolas do Concelho de Lisboa com idades compreendidas entre os 6 e os 11 anos (7,69±1,19), 670 encarregados de educação e 34 Professores. Para recolha de dados, foram utilizados três instrumentos: 2 questionários de perguntas fechadas, avaliação da função visual e prova de avaliação da leitura com 34 palavras. Após observadas, as crianças foram classificadas em dois grupos: função visual normal (FVN=562) e função visual alterada (FVA=110). Identificou-se uma prevalência de 16,4% de crianças com FVA. No teste de leitura, estas crianças apresentaram um menor número de palavras lidas corretamente (FVA=31,00; FVN=33,00; p<0,001) e menor precisão (FVA=91,18%; FVN=97,06%; p<0,001). Esta tendência também foi observada na comparação entre os 4 anos de escolaridade. As crianças com função visual alterada mostraram uma tendência para a omissão de letras e a confusão de grafema. Quanto à fluência (FVA=24,71; FVN=27,39; p=0,007) esta foi inferior nas crianças com FVA para todos os anos de escolaridade, exceto o 3º ano. As crianças com hipermetropia (p=0,003) e astigmatismo (p=0,019) não corrigido leram menos palavras corretamente (30,00; 31,00) e com menor precisão (88,24%; 91,18%) que as crianças sem erro refrativo significativo (32,00; 94,12%). A performance escolar classificada pelos professores foi inferior nas crianças com FVA e mais de ¼ necessitavam de medidas de apoio especial na escola. Não se verificaram diferenças significativas na performance da leitura das crianças com FVA por grupos de habilitações dos encarregados de educação. Verificou-se que o risco de ter um desempenho na leitura alterado é superior [OR=4,29; I.C.95%(2,49;7,38)] nas crianças que apresentam FVA. Relativamente ao 1º ano de escolaridade, o 2º, 3º e 4º anos apresentam um menor risco de ter um desempenho na leitura alterado. As variáveis método de ensino, habilitações dos encarregados de educação, tipo de escola (pública/privada), idade do Professor e número de anos de experiência do Professor, não foram fatores estatisticamente significativos para explicar a alteração do desempenho na leitura, quando o efeito da função visual se encontra contemplado no modelo. Um mau desempenho na leitura foi considerado nas crianças que apresentaram uma precisão inferior a 90%. Este indicador pode ser utilizado para identificar crianças em risco, que necessitam de uma observação Ortóptica/Oftalmológica para confirmação ou exclusão da existência de alterações da função visual. Este trabalho constitui um contributo para a identificação de crianças em desvantagem educacional devido a anomalias da função visual tratáveis, propondo um modelo que pretende orientar os professores na identificação de crianças que apresentem um baixo desempenho na leitura.
ABSTRACT - This thesis is a contribution for the study of visual function anomalies and reading performance. The aims were to: (1) identify the prevalence of visual function anomalies, (2) analyse reading performance in children with and without visual function anomalies, (3) identify the impact of visual function anomalies in reading performance and (4) identify the impact of variables which determine reading performance. A convenience sample with 672 children of school age (7.69±1.19), 670 parents and 34 teachers, was recruited in 11 Schools in Lisbon. Three instruments were used to collect the data: 2 questionnaires, visual function evaluation and reading performance evaluation with 34 words. Children were classified as normal visual function (NVF=562) and abnormal visual function (AVF=110). The prevalence of visual function anomalies was 16,4%. Children with AVF presented a lower number of correct words (AVF=31,00; NVF=33,00; p<0,001) and a lower precision (AVF=91,18%; NVF=97,06%; p<0,001). This tendency, was also observed when comparing children between the 4 grades. Children with AVF had a tendency to commit more omission errors and grapheme confusion. When comparing children between the 4 grades, fluency (AVF=24,71; NVF=27,39; p=0,007) was lower in children with AVF for all grades except for the 3rd grade. Children with hyperopia (p=0,003) and astigmatism (p=0,019) presented a lower number of correct words (30,00; 31,00) and a lower precision (88,24%; 91,18%) than children without a significant refractive error (32,00; 94,12%). Teacher’s recorded a lower academic performance in children with AVF and ¼ of them needed special measures for reading at school. There were no statistical differences in the academic performance of children with AVF regarding parent’s academic qualifications. The risk of having a low reading performance is higher in children with AVF [OR=4,29; I.C.95%(2,49;7,38)]. The 2nd, 3rd and 4th grades presented a lower risk of having a low reading performance. The variables teaching method, parent’s academic qualifications, school type (private/public), teacher’s age and teacher’s number of years of experience were not factors statistically significant to explain the reading performance, when the effect of visual function was contemplated in the model. A precision inferior to 90% was classified as low performance in reading. This indicator can be used to identify children at risk who need an orthoptic/ophthalmologic evaluation to confirm or exclude the presence of visual function anomalies. This study gives a contribution for identification and evaluation of children at educational disadvantage due to visual function anomalies that are treatable. A model to guide teacher’s in the identification of visual function anomalies that influence reading performance is proposed.

碩士
中臺科技大學
生物科技暨醫學工程研究所
107
Purpose: The purpose of this study was to establish a systematic survey method for the prevalence of non-strabismic binocular vision anomalies and to test the feasibility of the survey method. It is hoped that this survey method can be used in the future study of the prevalence of non-strabismic binocular vision anomalies in large-scale Taiwan. Methods: The study was conducted in two phases, and the first phase of the survey methodology consists of three tools: (1) Developing a questionnaire on abnormal symptoms of binocular vision, (2) Development of a binocular visual function test record, (3) Developing a diagnostic system for abnormal binocular vision. The Symptom questionnaire has a total of 26 questions. The topic contains common symptoms, and the severity of the symptoms is estimated by the frequency of occurrence. The questionnaire was also evaluated for expert validity and 42 healthy adults aged 18-35 were invited to perform inter-tester reliability and retest reliability assessment. The second phase of pilot study used this survey method to invite 30 healthy adults aged 18-35 years to perform an examination. The results of the examination were used to analyze the prevalence of binocular vision anomalies. Results: The Spearman's rho correlation coefficient between the inter-test reliability and the re-test reliability of the first phase 26-question questionnaire was 0.81-1.00 (p <0.001). In the the second phase pilot study (n=30), the total prevalence of non-strabismic binocular vision anomalies was 43.3% (n=13), of which 10% (n=3) was Convergence insufficiency, 10% (n=3) was Convergence excess, 0.0% (n=0) was Divergence insufficiency, 0.0% (n=0) was Divergence excess,10% (n=3) was Basic exophoria, 3.3% (n=1) was Basic esophoria, 3.3% (n=1) was Fusional vergence dysfunction, 3.3% (n=1) was Accommodative insufficiency, 0.0% (n=0) was Accommodative infacility and 3.3% (n=1) was Accommodative excess. Conclusion: The proposed method for investigating the prevalence of non-strabismic binocular vision anomalies developed in this study can be used as a follow-up large-scale research survey. Keywords: non-strabismic binocular vision anomalies, binocular vision, symptom questionnaire, reliability, prevalence

Dissertação de mestrado em Optometria Avançada
Antigamente as capacidades visuais utilizadas eram diferentes das que se usam hoje em dia, as tarefas (caça, pesca) requeriam menos esforço e capacidade visual, enquanto as tarefas que se utiliza hoje em dia por exemplo, as tarefas de visão de perto como ler, escrever, estudar, o tempo despendido no computador exigem um esforço acrescido do sistema visual. Certas pessoas não possuem um sistema visual capaz de realizar algumas actividades de visão de perto que exigem o uso sistema vergêncial e acomodativo de forma eficiente o que pode provocar fadiga, desconforto ocular, reduzindo consequentemente seu desempenho visual. Existem vários tipos de anomalias visuais como as disfunções acomodativas e vergenciais, estas podem interferir no desempenho escolar de um estudante ou até mesmo dificultar o desempenho de um atleta na sua actividade desportiva ou prejudicar a capacidade de eficiência no trabalho. A realização de uma certa quantidade de trabalho de perto como a leitura, ou uso contínuo de computadores é propensa ao desenvolvimento de sinais e sintomas relacionados com este tipo de disfunções acomodativas e vergenciais. Os sintomas normalmente associados a estas anomalias incluem visão turva, dor de cabeça, desconforto ocular, cansaço sistémico, diplopia, e perda de concentração durante a realização da tarefa. Neste sentido aplicou-se um inquérito a população universitária num total de 29 pacientes avaliados em duas fases distintas,1- no início do ano letivo, 2- no final da fase de exames – Janeiro-Fevereiro-. Este inquérito foi aplicado pela 1ª vez na população universitária, para avaliar e testar a sua viabilidade enquanto utensílio clinico houve a realização de Teste e Reteste. Os principais resultados obtidos permitem afirmar que para a pontuação direta da 1ª para a 2ª fase houve aumentou de forma estatisticamente significativa. Verificou-se que os participantes que pioram o seu diagnóstico da 1ª para a 2ª, ou seja, que tinham exames optométricos normais numa primeira fase e na segunda fase já possuíam parâmetros optométricos anómalos indicativos de disfunções da visão binocular, a sintomatologia aumentou de forma estatisticamente significativa.
In the past, the visual capacities used were different from those used today. Tasks (hunting, fishing) required less effort and visual capacity , while the tasks that are used nowadays for example, the near vision tasks such as reading, writing ,studying ,time spent on the computer require an increased effort of the visual system. Some people do not have a visual system capable of performing certain activities in near vision that require the use vergence and accommodative system efficiently which can cause fatigue, eye discomfort, thereby reducing its visual performance. There are several types of visual anomalies such as vergences and accommodative dysfunctions, which may interfere with school performance of a student or even hinder the performance of an athlete in a sport activity or impair the ability to work efficiently. The realization of a certain amount of near work such as reading or continuous use of computers is prone to the development of signs and symptoms related with this type of accommodative dysfunctions and vergence symptoms. The symptoms normally associated with these anomalies include blurred vision, headaches, eye discomfort, systemic weakness, diplopia, and loss of concentration while performing the task. In this sense it was applied a questionnaire to a total student population of 29 patients evaluated in two distinct phases , 1 - at the beginning of the school year , 2 - in the late stage of exams (January-February). This survey was applied for the first time in the university population, to evaluate and test its feasibility as a clinical survey was conducting Test Re-test. The main results obtained allow us to state that for the direct score from the 1st to the 2nd phase there was a statistically significantly increased. It was found that participants who worsen their diagnosis from 1st to 2nd phase, or in other words who had normal optometric examinations in the first phase and showed abnormal optometric parameters in the second phase indicating binocular vision disorders, their symptoms increased in a statistically significant way.