A population-based study of visual impairment among pre-school children in Beijing: the Beijing study of visual impairment in children.

PURPOSE: To evaluate the prevalence and causes of visual impairment among Chinese children aged 3 to 6 years in Beijing. DESIGN: Population-based prevalence survey. METHODS: Presenting and pinhole visual acuity were tested using picture optotypes or, in children with pinhole vision < 6/18, a Snellen tumbling E chart. Comprehensive eye examinations and cycloplegic refraction were carried out for children with pinhole vision < 6/18 in the better-seeing eye. RESULTS: All examinations were completed on 17,699 children aged 3 to 6 years (95.3% of sample). Subjects with bilateral correctable low vision (presenting vision < 6/18 correctable to >or= 6/18) numbered 57 (0.322%; 95% confidence interval [CI], 0.237% to 0.403%), while 14 (0.079%; 95% CI, 0.038% to 0.120%) had bilateral uncorrectable low vision (best-corrected vision of < 6/18 and >or= 3/60), and 5 subjects (0.028%; 95% CI, 0.004% to 0.054%) were bilaterally blind (best-corrected acuity < 3/60). The etiology of 76 cases of visual impairment included: refractive error in 57 children (75%), hereditary factors (microphthalmos, congenital cataract, congenital motor nystagmus, albinism, and optic nerve disease) in 13 children (17.1 %), amblyopia in 3 children (3.95%), and cortical blindness in 1 child (1.3%). The cause of visual impairment could not be established in 2 (2.63%) children. The prevalence of visual impairment did not differ by gender, but correctable low vision was significantly (P < .0001) more common among urban as compared with rural children. CONCLUSION: The leading causes of visual impairment among Chinese preschool-aged children are refractive error and hereditary eye diseases. A higher prevalence of refractive error is already present among urban as compared with rural children in this preschool population.

Cataract surgical outcomes, visual function and quality of life in four rural districts in Vietnam.

BACKGROUND: To evaluate cataract surgical outcomes in four rural districts of Ha Tinh Province, Vietnam. DESIGN: Cross-sectional study. PARTICIPANTS: Post-cataract surgery patients sampled randomly from facilities in four rural districts of Ha Tinh Province >3 months after surgery. MAIN OUTCOME MEASURES: Postoperative visual acuity (VA), visual function and quality of life. RESULTS: Among 412 patients, the mean age was 74.5 ± 9.4 years, 67% (276) were female, and 377 (91.5%) received intraocular lenses (IOL). Nearly two-thirds of patients had no postoperative visits after discharge. Postoperatively, more than 40% of eyes had presenting VA <6/18, while 20% remained <6/60. The mean self-reported visual function and quality of life for all patients were 68.7 ± 23.8 and 73.8 ± 21.6, respectively. Most patients (89.5%) were satisfied with surgery and the majority (94.4%) would recommend surgery to others. One-third of patients paid ≥$US50 for surgery. In multiple regression modelling, older age (P < 0.01), intraoperative complications (P < 0.01) and failure to receive an IOL (P < 0.01) were associated with postoperative VA <6/60. CONCLUSION: Satisfaction with surgery was high, and many patients were willing to pay for their operations. Poor visual outcomes were common; however, and better surgical training is needed to reduce complications and their impact on visual outcomes. More intensive postoperative follow-up may also be beneficial. © 2011 The Authors. Clinical and Experimental Ophthalmology © 2011 Royal Australian and New Zealand College of Ophthalmologists.

Early assessment of visual acuity after cataract surgery in rural Indonesia.

BACKGROUND: The accuracy and impact on service uptake of early examination after cataract surgery is not known. DESIGN:   Prospective cohort study. PARTICIPANTS: Cataract patients in rural Indonesia. METHODS: Visual acuity was measured preoperatively, 1day, 1-3, 4-6 and >12weeks after surgery, and 6-8months postoperatively at an outreach examination. Acceptance of second-eye surgery and spectacles was evaluated. MAIN OUTCOME MEASURE: Presenting visual acuity in the operated eye. RESULTS: Among 241 subjects (extracapsular surgery 84%), examinations at 1day, 1-3, 4-6 and >12weeks and 6-8months were completed for 100% (241), 90.9% (219), 67.6% (163), 22.0% (53) and 80.0% (193), respectively. Among subjects at the final examination (mean age 65.8±10.6years, 51.8% male), 73.6% had bilateral preoperative presenting visual acuity≤6/60. By 4-6weeks, the proportion with good (≥6/18) or poor (≤6/60) visual acuity did not differ significantly from the final examination. Among 49 persons accepting free second-eye surgery, 69.4% (34) and 16.3% (8) returned to clinic at 4-6 and >12weeks, respectively. Among 131 patients (67.9%) paying US$7 for glasses, 94 (71.8%) and 30 (22.9%) attended 4- to 6- and >12-week examinations, respectively. CONCLUSION: Even with large-incision surgery, early assessment of postoperative vision is representative of final vision, and may help deliver postoperative services to more of those needing them. © 2011 The Authors. Clinical and Experimental Ophthalmology © 2011 Royal Australian and New Zealand College of Ophthalmologists.

A Systematic Review of End-of-Life Visual Impairment in Open-Angle Glaucoma: An Epidemiological Autopsy

PURPOSE: Glaucoma patients are still at risk of becoming blind. It is of clinical significance to determine the risk of blindness and its causes to prevent its occurrence. This systematic review estimates the number of treated glaucoma patients with end-of-life visual impairment (VI) and blindness and the factors that are associated with this.

METHODS: A systematic literature search in relevant databases was conducted in August 2014 on end-of-life VI. A total of 2574 articles were identified, of which 5 on end-of-life VI. Several data items were extracted from the reports and presented in tables.

RESULTS: All studies had a retrospective design. A considerable number of glaucoma patients were found to be blind at the end of their life; with up to 24% unilateral and 10% bilateral blindness. The following factors were associated with blindness: (1) baseline severity of visual field loss: advanced stage of glaucoma or substantial visual field loss at the initial visit; (2) factors influencing progression: fluctuation of intraocular pressure (IOP) during treatment, presence of pseudoexfoliation, poor patient compliance, higher IOP; (3) longer time period: longer duration of disease and older age at death because of a longer life expectancy; and (4) coexistence of other ocular pathology.

CONCLUSIONS: Further prevention of blindness in glaucoma patients is needed. To reach this goal, it is important to address the risk factors for blindness identified in this review, especially those that can be modified, such as advanced disease at diagnosis, high and fluctuating IOP, and poor compliance.

A multi-attribute ranking solutions confirmation procedure

Ranking problems arise from the knowledge of several binary relations defined on a set of alternatives, which we intend to rank. In a previous work, the authors introduced a tool to confirm the solutions of multi-attribute ranking problems as linear extensions of a weighted sum of preference relations. An extension of this technique allows the recognition of critical preference pairs of alternatives, which are often caused by inconsistencies. Herein, a confirmation procedure is introduced and applied to confirm the results obtained by a multi-attribute decision methodology on a tender for the supply of buses to the Porto Public Transport Operator. © 2005 Springer Science + Business Media, Inc.

Promoção da acessibilidade em televisão interativa (iTV) : proposta de um serviço adaptado a utilizadores com défice visual

As infraestruturas de televisão interativa atualmente existentes possibilitam a integração de uma grande variedade de recursos e serviços, possibilitando aos utilizadores novas experiências de interação e participação. Para a maioria dos telespetadores, o uso de serviços interativos não acarreta grandes dificuldades; no entanto, para públicos com necessidades especiais, por exemplo para pessoas com défice visual, essa tarefa torna-se complexa, dificultando, ou mesmo impedindo, que estes utilizadores possam beneficiar deste tipo de serviços. Portugal não é uma exceção neste contexto, existindo um número significativo de utilizadores com défice visual (UDV) que não beneficiam totalmente das potencialidades do paradigma televisivo atual. Neste âmbito, o projeto de investigação que suporta esta tese explora a problemática do Design Universal aplicado à Televisão Interativa (iTV) e tem como objetivos a conceptualização, prototipagem e validação de um serviço de iTV adaptado especificamente a UDV, visando promover a sua inclusão digital. Para cumprir estes objetivos, a investigação dividiu-se em três etapas distintas. Na primeira etapa, a partir da Teoria Fundamentada nos Dados, foram identificadas as dificuldades e necessidades dos UDV enquanto consumidores de conteúdos televisivos e serviços de audiodescrição; foi selecionada a plataforma tecnológica mais adequada para o suporte do serviço prototipado; e foi definido um conjunto de princípios orientadores de design (POD’s) de interfaces de televisão interativa específico para este público-alvo. Inicialmente foram efetuadas duas entrevistas a 20 participantes com défice visual, para determinar as suas dificuldades e necessidades enquanto consumidores de conteúdos televisivos e serviços de audiodescrição. De seguida, foi realizada uma entrevista a um perito responsável pelo processo de transição para a TDT em Portugal (inicialmente considerou-se que a TDT seria uma plataforma promissora e poderia suportar o protótipo) e efetuada a revisão da literatura sobre POD’s para o desenvolvimento de interfaces para serviços iTV dirigidos a pessoas com défice visual. A partir dos resultados obtidos nesta etapa foi possível definir os requisitos funcionais e técnicos do sistema, bem como os seus PODs, tanto ao nível da componente gráfica, como de interação. Na segunda etapa foi concetualizado e desenvolvido o protótipo iTV adaptado a UDV ‘meo ad+’, com recurso à plataforma tecnológica IPTV da Portugal Telecom, seguindo os requisitos e os princípios de design definidos. Relativamente à terceira etapa, esta contemplou a avaliação do serviço prototipado, por parte de um grupo de participantes com défice visual. Esta fase do trabalho foi conduzida através do método de Estudo Avaliativo, possibilitando, através de testes de usabilidade e acessibilidade, complementados com entrevistas, compreender se o serviço prototipado ia efetivamente ao encontro das necessidades deste tipo de utilizadores, tendo-se observado que os participantes que estiveram envolvidos nos testes ao protótipo mostraram-se satisfeitos com as funcionalidades oferecidas pelo sistema, bem como com o design da sua interface.

Strength of visual percept generated by famous faces perceived without awareness: effects of affective valence, response latency, and visual field

Participants who were unable to detect familiarity from masked 17 ms faces ([Stone and Valentine, 2004] and [Stone and Valentine, in press-b]) did report a vague, partial visual percept. Two experiments investigated the relative strength of the visual percept generated by famous and unfamiliar faces, using masked 17 ms exposure. Each trial presented simultaneously a famous and an unfamiliar face, one face in LVF and the other in RVF. In one task, participants responded according to which of the faces generated the stronger visual percept, and in the other task, they attempted an explicit familiarity decision. The relative strength of the visual percept of the famous face compared to the unfamiliar face was moderated by response latency and participants’ attitude towards the famous person. There was also an interaction of visual field with response latency, suggesting that the right hemisphere can generate a visual percept differentiating famous from unfamiliar faces more rapidly than the left hemisphere. Participants were at chance in the explicit familiarity decision, confirming the absence of awareness of facial familiarity.

Narrative Personae and Visual Signs: Reading Leonard’s intimate photo-memoir. a/b: Auto/Biography Studies.

: In this paper, I look at Joanne Leonard’s Being in Pictures and engage in a critical dialogue with an assemblage of visual and textual narratives that comprise her intimate photo memoir. In doing this I draw on Hannah Arendt’s take on narratives as tangible traces of uniqueness and plurality, political traits par excellence in the cultural histories of the human condition. Being aware of my role as a reader/viewer/interpreter of a woman artist’s auto/biographical narratives, I move beyond dilemmas of representation or questions of unveiling “the real Leonard”. The artist is instead configured as a narrative persona, whose narratives respond to three interrelated themes of inquiry, namely the visualization of spatial technologies, vulnerability and the gendering of memory. Key words: gendered memories, narrative persona, spatial technologies, photo memoir, vulnerability

Beyond visual imagery: How modality-specific is enhanced mental imagery in synesthesia?

Synesthesia based in visual modalities has been associated with reports of vivid visual imagery. We extend this finding to consider whether other forms of synesthesia are also associated with enhanced imagery, and whether this enhancement reflects the modality of synesthesia. We used self‐report imagery measures across multiple sensory modalities, comparing synesthetes’ responses (with a variety of forms of synesthesia) to those of nonsynesthete matched controls. Synesthetes reported higher levels of visual, auditory, gustatory, olfactory and tactile imagery and a greater level of imagery use. Furthermore, their reported enhanced imagery is restricted to the modalities involved in the individual’s synesthesia. There was also a relationship between the number of forms of synesthesia an individual has, and the reported vividness of their imagery, highlighting the need for future research to consider the impact of multiple forms of synesthesia. We also recommend the use of behavioral measures to validate these self‐report findings.

Time in Perspective: a visual approach to models of time

Geographical representations of topographical space come in many shapes and are a regular topic of discussion. The depiction of the invisible and maybe even illusory concept of time on the other hand, remains largely unchanged and undisputed. A uniform and arithmetic model of time fits well with the rigid structure of digital data, which might be why it has been widely adopted within HCI. In our proposal, we will present historic and contemporary approaches that offer alternative perspectives on the visual representation of time. Keywords: timeline, chronographics

Improved line/edge detection and visual reconstruction

Lines and edges provide important information for object categorization and recognition. In addition, one brightness model is based on a symbolic interpretation of the cortical multi-scale line/edge representation. In this paper we present an improved scheme for line/edge extraction from simple and complex cells and we illustrate the multi-scale representation. This representation can be used for visual reconstruction, but also for nonphotorealistic rendering. Together with keypoints and a new model of disparity estimation, a 3D wireframe representation of e.g. faces can be obtained in the future.

Looking through the eyes of the painter: from visual perception to non-photorealistic rendering

In this paper we present a brief overview of the processing in the primary visual cortex, the multi-scale line/edge and keypoint representations, and a model of brightness perception. This model, which is being extended from 1D to 2D, is based on a symbolic line and edge interpretation: lines are represented by scaled Gaussians and edges by scaled, Gaussian-windowed error functions. We show that this model, in combination with standard techniques from graphics, provides a very fertile basis for non-photorealistic image rendering.