Glaucomatous visual field progression with frequency-doubling technology and standard automated perimetry in a longitudinal prospective study

PURPOSE. To compare frequency-doubling technology (FDT) perimetry with standard automated perimetry (SAP) for detecting glaucomatous visual field progression in a longitudinal prospective study.

METHODS. One eye of patients with open-angle glaucoma was tested every 6 months with both FDT and SAP. A minimum of 6 examinations with each perimetric technique was required for inclusion. Visual field progression was determined by two methods: glaucoma change probability (GCP) analysis and linear regression analysis (LRA). For GCP, several criteria for progression were used. The number of locations required to classify progression with FDT compared with SAP, respectively, was 1:2 (least conservative), 1:3, 2:3, 2:4, 2:6, 2:7, 3:6, 3:7, and 3:10 (most conservative). The number of consecutive examinations required to confirm progression was 2-of-3, 2-of-2, and 3-of-3. For LRA, the progression criterion was any significant decline in mean threshold sensitivity over time in each of the following three visual field subdivisions: (1) all test locations, (2) locations in the central 10° and the superior and inferior hemifields, and (3) locations in each quadrant. Using these criteria, the proportion of patients classified as showing progression with each perimetric technique was calculated and, in the case of progression with both, the differences in time to progression were determined.

RESULTS. Sixty-five patients were followed for a median of 3.5 years (median number of examinations, 9). For the least conservative GCP criterion, 32 (49%) patients were found to have progressing visual fields with FDT and 32 (49%) patients with SAP. Only 16 (25%) patients showed progression with both methods, and in most of those patients, FDT identified progression before SAP (median, 12 months earlier). The majority of GCP progression criteria (15/27), classified more patients as showing progression with FDT than with SAP. Contrary to this, more patients showed progression with SAP than FDT, when analysed with LRA; e.g., using quadrant LRA 20 (31%) patients showed progression with FDT, 23 (35%) with SAP, and only 10 (15%) with both.

CONCLUSIONS. FDT perimetry detected glaucomatous visual field progression. However, the proportion of patients who showed progression with both FDT and SAP was small, possibly indicating that the two techniques identify different subgroups of patients. Using GCP, more patients showed progression with FDT than with SAP, yet the opposite occurred using LRA. As there is no independent qualifier of progression, FDT and SAP progression rates vary depending on the method of analysis and the criterion used.

Methods for a population-based study of eye disease: the Melbourne Visual Impairment Project

The methodology of the Melbourne Visual Impairment Project, a major population-based survey of eye disease on 3,500 randomly selected individuals aged 40 years of age and over in the Melbourne metropolitan region, is presented. The aims of the study are to determine the distribution and determinants of eye disease in an urban population; the impact of eye disease on visual function and the activities of daily living; and the accessibility of eye health care services in the community. All procedures are conducted according to a standardised protocol to allow for comparison with other population-based studies, both in Australia and overseas. Information collected from this study will be employed in the development of recommendations related to eye health care service delivery and establishment of priorities for future public education programmes and health research.

The prevalence of glaucoma in the Melbourne Visual Impairment Project

PURPOSE: The purpose of the study was to determine the prevalence of glaucoma in Melbourne, Australia. METHODS: All subjects were participants in the Melbourne Visual Impairment Project (Melbourne VIP), a population-based prevalence study of eye disease that included residential and nursing home populations. Each participant underwent a standardized eye examination, which included a Humphrey Visual Field test, applanation tonometry, fundus examination including fundal photographs, and a medical history interview. Glaucoma status was determined by a masked assessment and consensus adjudication of visual fields, optic disc photographs, intraocular pressure, and glaucoma history. RESULTS: A total of 3271 persons (83% response rate) participated in the residential Melbourne VIP. The overall prevalence rate of definite primary open-angle glaucoma in the residential population was 1.7% (95% confidence limits = 1.21, 2.21). Of these, 50% had not been diagnosed previously. Only two persons (0.1%) had primary angle-closure glaucoma and six persons (0.2%) had secondary glaucoma. The prevalence of glaucoma increased steadily with age from 0.1% at ages 40 to 49 years to 9.7% in persons aged 80 to 89 years. There was no relationship with gender. The authors examined 403 (90.2% response rate) nursing home residents. The age standardized rate for this component was 2.36% (95% confidence limits = 0, 4.88). CONCLUSION: The rate of glaucoma in Melbourne rises significantly with age. With only half of patients being diagnosed, glaucoma is a major eye health problem and will become increasingly important as the population ages.

Polar luminance measurements : a direction in qualifying modelling

Through experimentation, it is revealed that the polar luminance method is capable of measuring the modelling of an object effectively in scenarios where the vector/scalar ratio is deficient. It is suggested that polar luminance measurement is a new direction for the measurement of modelling.

Glaucoma and on-road driving performance

PURPOSE. To investigate the on-road driving performance of patients with glaucoma.

METHODS. The sample comprised 20 patients with glaucoma and 20 subjects with normal vision, all licensed drivers, matched for age and sex. Driving performance was tested over a 10-km route incorporating 55 standardized maneuvers and skills through residential and business districts of Halifax, Nova Scotia, Canada. Testing was conducted by a professional driving instructor and assessed by an occupational therapist certified in driver rehabilitation, masked to participant group membership and level of vision. Main outcome measures were total number of satisfactory maneuvers and skills, overall rating, and incidence of at-fault critical interventions (application of the dual brake and/or steering override by the driving instructor to prevent a potentially unsafe maneuver). Measures of visual function included visual acuity, contrast sensitivity, and visual fields (Humphrey Field Analyzer; Carl Zeiss Meditec, Inc., Dublin, CA; mean deviation [MD] and binocular Esterman points).

RESULTS. There was no significant difference between patients with glaucoma (mean MD = −1.7 dB [SD 2.2] and −6.5 dB [SD 4.9], better and worse eyes, respectively) and control subjects in total satisfactory maneuvers and skills (P = 0.65), or overall rating (P = 0.60). However, 12 (60%) patients with glaucoma had one or more at-fault critical interventions, compared with 4 (20%) control subjects (odds ratio = 6.00, 95% CI, 1.46–24.69; higher still after adjustment for age, sex, medications and driving exposure), the predominant reason being failure to see and yield to a pedestrian. In the glaucoma group, worse-eye MD was associated with the overall rating of driving (r = 0.66, P = 0.002).

CONCLUSIONS. This sample of patients with glaucoma with slight to moderate visual field impairment performed many real-world driving maneuvers safely. However, they were six times as likely as subjects with normal vision to have a driving instructor intervene for reasons suggesting difficulty with detection of peripheral obstacles and hazards and reaction to unexpected events.

Relationship between vision impairment and ability to perform activities of daily living

Purpose: To determine the relationship between clinical measures of vision impairment and the ability to perform activities of daily living (ADLs).

Methods: One hundred and twenty subjects with low vision from a variety of causes participated in the study. Vision impairment was assessed under binocular conditions by measuring distance visual acuity, near word acuity, Melbourne Edge Test contrast sensitivity, Pelli–Robson Chart contrast sensitivity and visual fields. The ADL performance was assessed using the Melbourne Low Vision ADL Index (MLVAI), which is in part an observed performance assessment of instrumental ADLs and in part a self-report assessment of basic self-care ADLs.

Results: All vision measures had a high, statistically significant correlation with MLVAI total score. Near word acuity, had the strongest correlation (rs=−0.86, p < 0.001), followed by Melbourne Edge Test contrast sensitivity (rs=0.80, p < 0.001). Visual field had the weakest correlation (rs=0.56, p < 0.001). Together, age, near word acuity, Melbourne Edge Test contrast sensitivity and visual field accounted for 82.2% (adjusted R2, p < 0.001) of the variance in MLVAI total score. All correlations obtained were higher for the observed performance assessment of instrumental ADLs than for the self-report assessment of basic self-care ADLs.

Conclusions: Clinical vision impairment measures are highly correlated with capacity to perform ADLs, as measured by the MLVAI.

Exploring retinal and functional markers of diabetic neuropathy

Diabetic peripheral neuropathy (DPN) is one of the most debilitating complications of diabetes. DPN is a major cause of foot ulceration and lower limb amputation. Early diagnosis and management are key factors in reducing morbidity and mortality. Current techniques for clinical assessment of DPN are relatively insensitive for detecting early disease or involve invasive procedures such as skin biopsies. There is a need for less painful, non-invasive, safe evaluation methods. Eye-care professionals already play an important role in the management of diabetic retinopathy but recent studies have indicated that the eye may also be an important site for the diagnosis and monitoring of neuropathy. Corneal nerve morphology is a promising marker of diabetic neuropathy occurring elsewhere in the body. Emerging evidence tentatively suggests that retinal anatomical markers and a range of functional visual indicators could similarly provide useful information regarding neural damage in diabetes, although this line of research is less well established. This review outlines the growing body of evidence supporting a potential diagnostic role for retinal structure and visual functional markers in the diagnosis and monitoring of peripheral neuropathy in diabetes.

The third space : Metaphor and the disturbing observer

This book is a collaboration with a poet,a painter and two literary critics/philosophers. It is an investigation into aesthetics and examines and presents the possibilities for a poet and a painter in going beyond appropriating words and images from practitioners within their respective verbal and visual fields. In this book, the poet and the painter have been placed in a dialogic position to each other. This book attempts to create further meaning in the positioning of poems alongside paintings. It is a book about the processes of creativity, the making of art, the irresolvable dilemma of attempting to create from a world from which one cannot separate. The subject matter deals with art processes when attempting to re-discover lost identities with a focus on historical, psychological and political contexts

Measurement of the economic impact of visual impairment from age-related macular degeneration in Australia

The purpose of this report was to: (i) outline the potential value of health economic studies into age-related macular degeneration (AMD); (ii) provide an overview of health economic studies pertinent to AMD; and (iii) outline the basic frame work of cost-of-illness studies (a useful first step in applying economic methods). The detection and management of sensory loss in the elderly plays a key role in the Australian Government's Healthy Ageing Strategy. Age-related macular degeneration is currently the leading cause of blindness in elderly Australians. Although a large proportion of AMD cases remain untreatable, the introduction of photo­dynamic therapy provides a relatively expensive and possibly cost-effective innovation for others. Antioxidant therapy has also been proven effective in reducing progression of early to late disease. The discipline of economics can contribute to an understanding of AMD prevention and treatment through: (i) describing the current burden of disease; (ii) predicting the changes in the burden of disease over time, and (iii) evaluating the efficiency of different interventions. Cost-of-illness studies have been performed in many fields of medicine. Little work, however, has been done on describing the economic impact from AMD. A number of different economic evaluation methods can be used in judging the efficiency of possible interventions to reduce the disease burden of AMD. Although complementary in nature, each has specific uses and limitations. Studies of the economic impact of eye diseases are both feasible and necessary for informed health care decision-making.

Visual research methods in education: in between difference and indifference

The aim of this paper is to support critical and scholarly debates that relate to the increasing role of visual research in education, youth studies, sociology, and studies of mental health. Researching in fields where young people are central exposes many struggles, not least issues of how to represent students who end up on the margins. School disaffection intersects with curriculum practices. When threading together visual research methods and matters of curriculum studies, seduction can set in, and unintentionally curriculum research can become indifferent to difference, the counterpoint often sought by researchers. Some scholars may argue that this debate has been well rehearsed in the curriculum field; I, however, take the opposite view. The constraints of curriculum studies, issues of student disaffection and the exclusions of schooling - when analysed through the perspectives of visual research - trouble our research designs and understandings of data and therefore require more, not less, interrogation. Rethinking the intersection points between visual research methods (VRM) and visuality, a concept that is critical to cultural and visual studies, opens out new spaces in the field of curriculum studies and reframes the methodological decisionmaking process for researching issues that pertain to student disaffection. 

Becoming an artist: life histories and visual images

Chapter summary:
In this chapter, we consider the experiences of an art/research experiment that took place in the context of the annual conference of the British Sociaological Association (BSA), held at the University of East London in April 2007. The essay is in four parts: in the first section, the researcher gives the context of the project that underpinned the BSA event, mapping its theoretical directions and methodological moves. In the second section, the artist tells stories of becoming through words and images. The force of the artist’s narrative challenges and reconfigures discursively constructed boundaries between the researcher and the artist, initiating a dialogic encounter that unfolds in the third section as a visual/textual interface. This encounter revolves around the quest for meaning, which is after all what oral history is about (Portelli, 2011). Our quest for meaning actually inspired us to write about and problematize the BSA event. In this light, the final section looks critically into some of the questions that have arisen, situating them within wider problematics in the field of oral histories and narrative research.

Book summary:
Interviews are becoming an increasingly dominant research method in art, craft, design, fashion and textile history. This groundbreaking text demonstrates how artists, writers and historians deploy interviews as creative practice, as 'history', and as a means to insights into the micro-practices of arts production and identity that contribute to questions of 'voice', authenticity, and authorship. Through a wide range of case studies from international scholars and practitioners across a variety of fields, the volume maps how oral history interviews contribute to a relational practice that is creative, rigorous and ethically grounded.

Leveraging visual features and hierarchical dependencies for conference information extraction

Traditional information extraction methods mainly rely on visual feature assisted techniques; but without considering the hierarchical dependencies within the paragraph structure, some important information is missing. This paper proposes an integrated approach for extracting academic information from conference Web pages. Firstly, Web pages are segmented into text blocks by applying a new hybrid page segmentation algorithm which combines visual feature and DOM structure together. Then, these text blocks are labeled by a Tree-structured Random Fields model, and the block functions are differentiated using various features such as visual features, semantic features and hierarchical dependencies. Finally, an additional post-processing is introduced to tune the initial annotation results. Our experimental results on real-world data sets demonstrated that the proposed method is able to effectively and accurately extract the needed academic information from conference Web pages. © 2013 Springer-Verlag.

A cavalcade of erasures: an educational audio-visual presentation

Dirk de Bruyn has been creating film works for over 35 years; mostly in the hand-made, 'direct animation' mode. He also performs live with multiple projections of his films in a highly embodied mode of expanded cinema performance. His work is renowned for its intricate, suggestive layering of sound and image, and use of sumptuous, blooming fields of colour.An active participant in our PyR16, Dirk will be discussing his conceptual work, his meticulous creative process, and his particular relationship with the materials, light, space and time both on film and stage, illustrating with some examples.We'll conclude with a Q&A session with the attendants.