Paper Session III-C - The Low Vision Enhancement System: A Decade Long Technology Transfer Project

There are approximately 2 million people in the United States who cannot function normally in society due to vision impairment. Yet, most of these people retain some sight. Until recently available treatments were essentially unchanged from those available 50 years ago. Options included various hand magnifiers, colored lenses, and telescopes mounted to glasses. The one recent innovation was the development of a stand-mounted, closed-circuit television. Collectively, these aids were often of limited utility. For example a hand lens is of little value when walking, watching television or shopping. As the result of a conscience decision the Wilmer Eye Institute, a part of The Johns Hopkins University, contacted NASA. They wished to learn if NASA had new technology that could help low vision patients. As a result in 1985 the two parties began working together, developing an aid for the vision handicapped. Their efforts, along with that of many other organizations that subsequently joined, have created a system of technology that will have impact far beyond the original target population

Functional Outcomes of the Low Vision Depression Prevention Trial in Age-Related Macular Degeneration.

Purpose: To compare the efficacy of behavioral activation (BA) plus low vision rehabilitation with an occupational therapist (OT-LVR) with supportive therapy (ST) on visual function in patients with age-related macular degeneration (AMD). Methods: Single-masked, attention-controlled, randomized clinical trial with AMD patients with subsyndromal depressive symptoms (n = 188). All subjects had two outpatient low vision rehabilitation optometry visits, then were randomized to in-home BA + OT-LVR or ST. Behavioral activation is a structured behavioral treatment aiming to increase adaptive behaviors and achieve valued goals. Supportive therapy is a nondirective, psychological treatment that provides emotional support and controls for attention. Functional vision was assessed with the activity inventory (AI) in which participants rate the difficulty level of goals and corresponding tasks. Participants were assessed at baseline and 4 months. Results: Improvements in functional vision measures were seen in both the BA + OT-LVR and ST groups at the goal level (d = 0.71; d = 0.56 respectively). At the task level, BA + OT-LVR patients showed more improvement in reading, inside-the-home tasks and outside-the-home tasks, when compared to ST patients. The greatest effects were seen in the BA + OT-LVR group in subjects with a visual acuity ≥20/70 (d = 0.360 reading; d = 0.500 inside the home; d = 0.468 outside the home). Conclusions: Based on the trends of the AI data, we suggest that BA + OT-LVR services, provided by an OT in the patient\u27s home following conventional low vision optometry services, are more effective than conventional optometric low vision services alone for those with mild visual impairment. (ClinicalTrials.gov number, NCT00769015.)

Evaluation of the NEI visual functioning questionnaire as an interval measure of visual ability in low vision

AbstractThe National Eye Institute developed a visual functioning questionnaire (NEI-VFQ) designed to assess health-related quality of life of patients with visual impairments. The developers of the NEI-VFQ distributed the original 52 items into 13 different domains. The recommended method for scoring the NEI-VFQ is to linearly transform the sum of the ordinal ratings to each item within each domain to produce 13 scores. The major shortcoming of this scoring method is that sums of ordinal numbers do not necessarily generate valid measurement scales. However, Rasch models can be used to estimate interval measurement scales from ordinal responses to items. We administered 27 items from the 52-item NEI-VFQ to 341 patients with low vision. Rasch analysis was used to estimate the ‘visual ability’ required by each item for a particular response (item measures) and to estimate the ‘visual ability’ of each patient (person measures). The validity of the model was evaluated by examining the distributions of residuals for item and person measures. We observed that the 17 items we tested from the NEI-VFQ that require difficulty ratings produce a valid interval scale for low-vision patients. The estimated person measures of visual ability are linear with log MAR acuity. The ten items that require frequency or level of agreement ratings do not work together to produce a valid interval scale. Rather, these items appear to be confounded by other variables distributed in the patient sample (e.g. psychological state). The visual ability scale estimated from the 17 NEI-VFQ items is proportional to the visual ability scales estimated from two earlier studies that also elicited difficulty ratings from low-vision patients

Auditory assistive devices for the blind

Proceedings of the 9th International Conference on Auditory Display (ICAD), Boston, MA, July 7-9, 2003.Most auditory assistive devices for the Blind employ synthetic speech. These include talking computer interfaces, reading machines, talking signs, and a plethora of talking appliances and gadgets. Some devices use warning tones to signal events or localize objects. Sonification in assistive devices is limited to wayfinding systems that encode range into frequency. There are now some prototype systems that offer more complex sonifications for wayfinding and interpreting images. There still are no assistive devices that use both 3D sound and sonification to augment the auditory environment

Visual and health outcomes, measured with the activity inventory and the EQ‐5D, in visual impairment

Purpose: Generic instruments to assess health utilities can be used to express the burden of health problems in widely used indexes. That is in contrast with what can be obtained with condition-specific instruments, outcomes are very specific and difficult to compare across conditions. The purpose of this study was to assess health and visual outcomes and its determinants in patients with visual impairment (VI) using the EQ-5D-3L and the Activity Inventory (AI). Methods: Participants were recruited in different hospitals during the PCVIPstudy. A total of 134 patients with acuity 0.30 logMAR or less in the better eye were interviewed. The AI includes 46 goals split between three objectives: social functioning, recreation and daily living, and was used to measure visual ability. The EQ-5D consists of five questions covering one domain each and was used to provide a measure of health states. Responses to each domain were combined to produce a single individual index. Results: The AI and the EQ-5D-3L showed enough discriminatory power between VI levels (p < 0.001), and their results were strongly correlated r(134) = 0.825, (p < 0.001). Explanatory factors for visual ability were level of VI in better eye, age and gender, R2 = 0.43, (p < 0.001). Explanatory factors for the EQ-5D-3L were level of VI in the better eye, comorbidities and gender, R2 = 0.36, (p < 0.001). Conclusion: Our results showed that the EQ-5D-3L is useful when characterizing the burden of VI and to compute, when necessary, quality-adjusted-lifeyears (QALY) changes due to VI. However, it is important to consider that the EQ-5D-3L uses a coarse response scale, assesses a limited spectrum of domains and is influenced by comorbidities. This might limit its responsiveness to small changes in visual ability.In this study, we investigated factors affecting visual and health outcomes measured by EQ-5D and the Activity Inventory in patients with visual impairment. This study was supported by FCT (COM-PETE/QREN) grant reference PTDC/DPT-EPI/0412/2012 in the context of the Prevalence and Costs of Visual Impairment in Portugal: PCVIP-study. Authors report on behalf of the Portuguese visual impairment study group (PORVIS-group): Amandio Rocha-Sousa, MD, PhD, Ophthalmologist; Marta Silva, MD, ophthalmology resident; Sara Perestrelo, MD, ophthalmology resident; Joao Tavares-Ferreira, MD, Ophthalmologist; Ana Marta Oliveira, research coordinator; Department of Organs of Senses, Faculty of Medicine University of Porto and/or Department of Ophthalmology, Centro Hospitalar de Sao Joao and/or Unidade de Investigacao do CHSJ - Centro de Epidemiologia Hospitalar. Cristina Freitas, MD Ophthalmologist; Keissy Sousa, MD Ophthalmologist; Ricardo Leite, MD, ophthalmology resident; Jose Ferreira Mendes, MD, ophthalmology resident; Andreia Braga Soares, MD, ophthalmology resident; Rui Carneiro Freitas, MD, ophthalmology resident; Department of Ophthalmology, Hospital de Braga. Pedro Reimao, MD, Ophthalmologist; Marco Vieira, MD, Ophthalmologist; Joel Monteiro, MD, cardiology resident; Department of Ophthalmology, Centro Hospitalar de Alto Ave, Guimaraes. Natacha Moreno, MD, Ophthalmologist; Department of Ophthalmology, Hospital Sta Maria Maior, Barcelos. Gary Rubin, PhD (project adviser); UCL-Institute of Ophthalmology, London, UK. We would like to acknowledge Hospital de Braga/Ophthalmology Department and Clinical and Academic Centre and Centro Hospitalar do Alto Ave for their help at selecting and recruiting participants for this study and an anonymous reviewer for providing advice about the manuscript. Part of this work has been presented in ARVO2015 annual meeting, Denver, Colorado, and also accepted for presentation in the Public Health Conference, Milan, October 2015.info:eu-repo/semantics/publishedVersio

Psychological and cognitive determinants of vision function in age-related macular degeneration.

OBJECTIVE: To investigate the effect of coping strategies, depression, physical health, and cognition on National Eye Institute Visual Function Questionnaire scores obtained at baseline in a sample of older patients with age-related macular degeneration (AMD) enrolled in the Improving Function in AMD Trial, a randomized controlled clinical trial that compares the efficacy of problem-solving therapy with that of supportive therapy to improve vision function in patients with AMD. METHODS: Baseline evaluation of 241 older outpatients with advanced AMD who were enrolled in a clinical trial testing the efficacy of a behavioral intervention to improve vision function. Vision function was characterized as an interval-scaled, latent variable of visual ability based on the near-vision subscale of the National Eye Institute Vision Function Questionnaire-25 plus Supplement. RESULTS: Visual ability was highly correlated with visual acuity. However, a multivariate model revealed that patient coping strategies and cognitive function contributed to their ability to perform near-vision activities independent of visual acuity. CONCLUSIONS: Patients with AMD vary in their coping strategies and cognitive function and in their visual acuity, and that variability determines patients\u27 self-report of vision function. Understanding patient coping mechanisms and cognition may help increase the precision of vision rating scales and suggest new interventions to improve vision function and quality of life in patients with AMD. Trial Registration clinicaltrials.gov Identifier: NCT00572039

Review of Machine Vision-Based Electronic Travel Aids

Visual impaired people have navigation and mobility problems on the road. Up to now, many approaches have been conducted to help them navigate around using different sensing techniques. This paper reviews several machine vision- based Electronic Travel Aids (ETAs) and compares them with those using other sensing techniques. The functionalities of machine vision-based ETAs are classified from low-level image processing such as detecting the road regions and obstacles to high-level functionalities such as recognizing the digital tags and texts. In addition, the characteristics of the ETA systems for blind people are particularly discussed