Insight into light:The influence of luminance on visual functioning in glaucoma

Glaucoma is a progressive eye disease in which the visual field is permanently damaged but which remains without symptoms until a late stage. Visual field loss in one eye is compensated by the other eye and the brain fills in missing parts. At the ophthalmology outpatient clinic, many glaucoma patients indicated that they experienced difficulty with seeing in extreme (low, high and rapidly changing) luminance conditions – complaints that are not typical for glaucoma. Therefore, the aim of this thesis was to unravel the effect of luminance on the visual function of glaucoma patients. With a questionnaire, we confirmed glaucoma patients had much more difficulty with seeing in extreme luminance conditions, especially in the dark. In a series of experiments we found that glaucoma patients had a standard amount of lower vision in all luminance conditions; from very dark to extremely light. Glaucoma patients did not need longer adaptation times to get used to the dark. With the national citizen science project ‘Insight into light’ we used an app to map the luminance of the Netherlands at night. 6700 measurements of almost 2000 people showed that subjects with an eye disease had more difficulty with walking at night than subjects without an eye disease – an interesting fact given the trend towards fewer streetlights. This thesis confirms that glaucoma patients see less in all luminance conditions and this can be a considerable challenge especially in the dark. Further research is needed to confirm whether these findings can help us to diagnose glaucoma more efficiently in the future

Visual Performance as a Function of Luminance in Glaucoma:The De Vries-Rose, Weber's, and Ferry-Porter's Law

PURPOSE. To determine whether the De Vries-Rose, Weber's, and Ferry-Porter's law, which describe visual performance as a function of luminance, also hold in patients with glaucoma. METHODS. A case-control study with 19 glaucoma patients and 45 controls, all with normal visual acuity. We measured foveal and peripheral contrast sensitivity (CS) using static perimetry and foveal and peripheral critical fusion frequency (CFF; stimulus diameter 1 degrees) as a function of luminance (0.02 to 200 cd/m(2)). ANOVA was used to analyze the effect of glaucoma and luminance on CS and CFF; analyses were adjusted for age and sex. RESULTS. Foveally, logCS was proportional to log luminance at lower luminances (de Vries-Rose) and saturated at higher luminances (Weber); glaucoma patients had a 0.4 log unit lower logCS than controls (P <0.001), independent of luminance. Peripherally, the difference was more pronounced at lower luminances (P = 0.007). CFF was linearly related to log luminance (Ferry-Porter). Glaucoma patients had a lower CFF compared with controls (P <0.001), with a smaller slope of the CFF versus log luminance curve, for both the fovea (6.8 vs. 8.7 Hz/log unit; P <0.001) and the periphery (2.5 vs. 3.4 Hz/log unit; P = 0.012). CONCLUSIONS. Even in apparently intact areas of the visual field, visual performance is worse in glaucoma patients than in healthy subjects for a wide range of luminances, without a clear luminance dependency that is consistent across the various experiments. This indicates impaired signal processing downstream in the retina and beyond, rather than an impaired light adaptation in the strictest sense

Increased risk of subsequent neoplasm after hematopoietic stem cell transplantation in 5-year survivors of childhood acute lymphoblastic leukemia

Acute lymphoblastic leukemia (ALL) survivors are at risk for developing subsequent neoplasms, but there is limited information on long-term risks and risk factors for both subsequent malignant neoplasms (SMNs) and subsequent non-malignant neoplasms (SNMNs). We analyzed long-term risk and risk factors for SMNs and SNMNs among 3291 5-year ALL survivors from the Dutch Childhood Cancer Survivor Study-LATER cohort (1963–2014). We calculated standardized incidence ratios (SIRs) and cumulative incidences and used multivariable Cox proportional hazard regression analyses for analyzing risk factors. A total of 97 survivors developed SMNs and 266 SNMNs. The 30-year cumulative incidence was 4.1% (95%CI: 3.5–5.3) for SMNs and 10.4%(95%CI: 8.9–12.1) for SNMNs. Risk of SMNs was elevated compared to the general population (SIR: 2.6, 95%CI: 2.1–3.1). Survivors treated with hematopoietic stem cell transplantation (HSCT) with total body irradiation (TBI) (HR:4.2, 95%CI: 2.3–7.9), and without TBI (HR:4.0,95%CI: 1.2–13.7) showed increased SMN risk versus non-transplanted survivors. Cranial radiotherapy (CRT) was also a risk factor for SMNs (HR:2.1, 95%CI: 1.4–4.0). In conclusion, childhood ALL survivors have an increased SMN risk, especially after HSCT and CRT. A key finding is that even HSCT-treated survivors without TBI treatment showed an increased SMN risk, possibly due to accompanied chemotherapy treatment. This emphasizes the need for careful follow-up of HSCT and/or CRT-treated survivors.</p

Insight into light: The influence of luminance on visual functioning in glaucoma

Glaucoma is a progressive eye disease in which the visual field is permanently damaged but which remains without symptoms until a late stage. Visual field loss in one eye is compensated by the other eye and the brain fills in missing parts. At the ophthalmology outpatient clinic, many glaucoma patients indicated that they experienced difficulty with seeing in extreme (low, high and rapidly changing) luminance conditions – complaints that are not typical for glaucoma. Therefore, the aim of this thesis was to unravel the effect of luminance on the visual function of glaucoma patients. With a questionnaire, we confirmed glaucoma patients had much more difficulty with seeing in extreme luminance conditions, especially in the dark. In a series of experiments we found that glaucoma patients had a standard amount of lower vision in all luminance conditions; from very dark to extremely light. Glaucoma patients did not need longer adaptation times to get used to the dark. With the national citizen science project ‘Insight into light’ we used an app to map the luminance of the Netherlands at night. 6700 measurements of almost 2000 people showed that subjects with an eye disease had more difficulty with walking at night than subjects without an eye disease – an interesting fact given the trend towards fewer streetlights. This thesis confirms that glaucoma patients see less in all luminance conditions and this can be a considerable challenge especially in the dark. Further research is needed to confirm whether these findings can help us to diagnose glaucoma more efficiently in the future

Chronotyping glaucoma patients with the Munich ChronoType Questionnaire: A case-control study.

PURPOSE:The circadian clock is entrained to light by the intrinsically photosensitive retinal ganglion cells. Loss of these cells in glaucoma, an eye disease with loss of retinal ganglion cells as its key feature, might thus result in a change in chronotype. We aimed to compare the chronotype between glaucoma patients and healthy subjects. METHODS:We sent the Munich ChronoType Questionnaire to 221 glaucoma patients (response rate 81%); controls (primary control group) were primarily their spouses. After exclusion of shift workers and participants who woke-up due to an alarm clock on days off, 159 glaucoma patients (88 early, 21 moderate, 23 severe) and 163 controls remained. We calculated chronotype as the mid-sleep on days off, corrected for workweek accumulated sleep debt (MSFsc). We compared means and variances between groups using Welch's tests and F-tests, respectively. A secondary control group was recruited from participants in a citizen-science project (n = 17073) who completed an online questionnaire. A resampling method was applied to enable an age- and gender- matched comparison with the glaucoma patients. RESULTS:Compared to the primary control group, glaucoma did not affect the mean MSFsc (controls 3:47; early, moderate, and severe glaucoma 3:40, 3:45, and 3:33, respectively [P = 0.62]). Chronotype variability seemed to increase with increasing disease severity (severe glaucoma versus controls: P = 0.023). The mean MSFsc of the secondary control group was 3:50 (95% confidence interval 3:48 to 3:52); significantly later than that of the glaucoma patients (3:40; P = 0.024). Mean MSFsc did not differ significantly between the control groups (P = 0.42). CONCLUSIONS:No clear changes were found in the chronotype as determined by sleep phase in patients with glaucoma, especially not in early and moderate glaucoma. In severe glaucoma, chronotype variability seems to increase, possibly alongside a small advancement

Intervening factors of loyalty in a bank branch: a case study with servers of prefecture São Paulo

O setor de serviços, onde os bancos estão inseridos, se caracteriza pelo o uso intenso de recursos humanos, grande heterogeneidade de atividades e simultaneidade entre produção e consumo de produtos/serviços. Este contexto torna bastante complexo e desafiador a proposição de especificações de qualidade que contribuam com o aumento da satisfação e da lealdade dos clientes. Embasado em fundamentação teórica sobre os temas setor de serviços, qualidade, satisfação, imagem corporativa, lealdade e valores humanos, este trabalho se propôs a buscar uma melhor compreensão sobre como estes fatores atuam em uma agência bancária. O estudo foi executado em uma agência bancária de médio porte localizada na região metropolitana de São Paulo. Para cumprir com os objetivos de pesquisa foram realizadas entrevistas, observações durante o expediente bancário e pesquisa de campo com 202 clientes. A fase qualitativa, composta pelas entrevistas e pelas observações, foi transcrita e consolidada segundo a relevância das informações colhidas; na fase quantitativa, após a coleta de dados, foram realizadas análises estatísticas em contexto univariado, bivariado e multivariado por meio das técnicas de Análise fatorial, Análise de conglomerados, Análise de regressão logística e Modelagem de equações estruturais. Os resultados indicam que a qualidade funcional é o fator mais importante da qualidade na agência bancária objeto de estudo. O estudo demonstrou, também, que a capacidade de compreender as necessidades individuais, um relacionamento comercial pautado na transparência e na integridade e o valor humano de responsabilidade sócio-ambiental contribuem na diferenciação entre clientes leais e não leais a agência bancária em questão. O trabalho também indicou que há uma relação direta entre os construtos Lealdade, Qualidade, Satisfação e Valores humanos.The service sector, in which banks have been inserted, is characterized by the intense use of human resources, heterogeneity and simultaneity of activities between production and consumption of products / services. This condition makes it quite complex and challenging proposing quality specifications that contributes to increase customer satisfaction and loyalty. Based in theoretical grounding on service\'s sector main themes, such as quality, satisfaction, loyalty, corporate image and human values issues, this study proposes to seek a better understanding of how these factors work in a bank. The study had been performed in a midsize bank agency located in the metropolitan region of São Paulo. To accomplish research goals, interviews, observations during business hours and fieldwork surveys were made with 202 clients. In the qualitative step, which is consisted by the interviews and observations, the information has been transcribed and consolidated according to relevance. In the quantitative step, after data collection, statistical analyzes were performed in univariate context, bivariate and multivariate analysis through factorial analysis techniques, cluster analysis, logistics regression analysis and structural equation modeling. The results suggests that functional quality is the most important factor in the quality of bank\'s agency object of study. The study also evidenced that the ability to understand individual needs, a business relationship built on transparency and integrity and the human value of social and environmental responsibility contributes in differentiating loyal and non-loyal agency\'s customers. The study also indicated that there is a direct relation between the Loyalty, Quality, Satisfaction and human values constructs

Characteristics of study population.

<p>Characteristics of study population.</p