Research

Researchers listed alphabetically by surname

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Researchers listed by country index
Researchers listed by subject index

D

Prof. Gislin Dagnelie
The Wilmer Eye Institute, Johns Hopkins Hospital, 600 N. Wolfe St., Baltimore, MD 21287, United States of America.
Tel: +1 410 614 4822
Email: gdagnelie@jhmi.edu
Web: www.hopkinsmedicine.org/
P ublications

Current & recent projects

Clinical evaluation of the ASR device for the treatment of vision loss from retinitis pigmentosa
This study is an FDA-approved phase I/II clinical trial of the Optobionics ASR chip in retinitis pigmentosa patients. Eight patients were implanted in December 2004 and February 2005, and are being followed for any changes to their vision that may be attributed to the presence of the ASR implant in one eye. The hypothesis driving the study is that the small current emanating from the ASR will trigger the release of various nerve protective agents, which will in turn improve the health of the remaining photoreceptors, leading to better vision in the implanted eye.
Project start date: 11/2004
Project end date: 10/2006

Novel vision tests: data analysis from a RP lutein trial
This study uses analysis of the stability and consistency of PC based test results to assess the validity of the PC-based tests. In addition, the study examines data collected from RP patients taking lutein supplements and additional control subjects (some with RP and others normally-sighted) to determine the time course and potential effects of lutein on vision in RP patients. Comparisons of PC-based outcome measures with lab-based outcome measures are made to evaluate the reproducibility of the PC-based methods. The PC based tests are weekly, self-administered tests on each participant’s home PC. Findings of the study may be useful in the development of an inexpensive, effective method of monitoring vision between clinic visits in future clinical trials.
Project start date: 04/2003
Project end date: 03/2005

Enhanced retinal prosthetics through infrared imaging
The purpose of this study is to determine the advantages of using infrared and fused infrared/visible wavelength imaging, relative to the use of visible wavelength input only, while conducting a variety of human performance tasks. To estimate the benefits of the heat-mediated IR imagery to low vision patients and retinal implant recipients, this study compares the results from vision-based tasks completed by normally sighted subjects wearing a head mounted simulator with those normally sighted subjects using conventional video simulated images and the results of initial retinal prosthesis patients. Findings of the study will aid in the development of a fused Infrared/Visual front end to a retinal implant system.
Project start date: 05/2003
Project end date: 04/2005

Studies of simulated prosthetic vision
This study aims at supporting the development of prosthetic vision through simulations in normally sighted and visually impaired volunteer subjects. Testing involves the presentation of “prosthetic” phosphene images through a view of a small number (16-256) of dots 1-2 inches in diameter, with varying Gaussian intensity profiles. The images are presented to subjects using a head-mounted video display system, which provides built-in eye tracking. Three modes of presentation in the reading and face recognition testing are used. The first mode enables the subject to use the pixel raster as a movable window onto the stationary background by moving the computer mouse. In the second mode of testing, movement of the raster is controlled with the eye-tracking system. The raster is stabilized on the retina while allowing movement across the stationary image. The third mode allows raster movement through eye tracking while the underlying image can be moved with the computer mouse. The testing provides information regarding resolution and dot sizes required for pixelized vision and regarding the feedback of head and eye movement required for maximized visual information transfer. Indirectly the study also provides knowledge of spatiotemporal visual processing and visual perception under conditions of spatial sampling. Findings will be used to derive effective methods for intraoperative testing and to optimize further research with future visual prosthesis wearers.
Project start date: 08/2000
Project end date: 07/2005

Last updated: 26/11/2007

David Dewhurst
Email: info@stve.org
Web: www.STVE.org

Current & recent projects

The Vuphonics system
The "Vuphonics" system is an experimental sensory-substitution system for use by blind and deafblind people. The Vuphonics system highlights the features of visual images that are normally perceived categorically, by substituting with coded sound effects and their tactile equivalents. It simulates the "instant recognition" of properties and objects that occurs in visual perception, by using the near-instantaneous recognition of phoneme sounds that occurs in speech. By listening to coded phonetic sounds (and feeling corresponding tactile/braille effects), the user can instantly understand the colours, textures, distances and "entities" that are present in an image. The system also conveys shape, location, "fine texture" and "change".
Ongoing

Permanently-Embossed Band Tactile Displays
Many blind and deafblind people use the braille and Moon tactile codes for reading, and computer-controlled braille displays allow varying braille "dots" to be displayed, conveying text that would otherwise be displayed on a computer monitor for sighted people to read. Most existing braille displays require a controlled "actuator" (movement-causing device) for each braille dot. PEB (Permanently-Embossed Band) Tactile Displays would present varying tactile representations of text, and of simple pixel-based tactile graphics, using a reduced number of components. Several independently-moveable bands (or discs, or rods) would each be permanently embossed with several braille dots or other tactile characters or pixels. The bands would move relative to each other in order to either present the required tactile characters, or to form simple pixel-based tactile graphics.
Ongoing

Distant Assistance System
There are many technological aids for blind people, for example electronic travel aids (ETAs) and speaking reading machines. However certain information is difficult for automatic devices to interpret: shape and object recognition is only practical for particular items that are presented in a controlled way, e.g. optical character recognition (OCR). Blind people may prefer the flexible help and non-robotic voice that a person can provide, but such assistance is not always available. The "Distant Assistance System" as envisaged would provide blind people (or other sense-impaired people e.g. deaf people) with assistance from other people on a planned or ad-hoc basis, by matching clients to volunteer assistants, who may be located far from the clients. The Internet allows images and sound to be sent near-instantaneously between people located around the world. The suggested system would use a dedicated Internet website and standard communication methods. Video and audio data would be "streamed" in "realtime" from the clients to the assistants, who would describe the audiovisuals, give mobility advice etc. The feedback would be returned to the clients near-instantaneously, and in a modality that they can comprehend.
Ongoing

Last updated: 28/11/2007

Prof. Chris Dickinson
University of Manchester, Faculty of Life Sciences, Moffat Building
PO Box 88, Sackille Street, Manchester, M60 1QD
Tel: +44 (0)161 306 3874
Fax: +44 (0)161 306 3887
Email: chris.dickinson@manchester.ac.uk
Web: www.ls.manchester.ac.uk/
Publications

Current & recent projects

The comparative effectiveness of conventional versus autofocus telescopic low vision aids
The successful use of magnifiers does not just depend on visual factors. In an investigation on naïve subjects it has been found that manual dexterity plays a major role in how fast an individual can read with such a device. Work with education colleagues in the Manchester Service for Visually Impaired Children is aiming to developing appropriate methods to assess the relative merits of using magnifiers compared to (for example) large print and additional classroom assistance.
Ongoing

Assessment of disability
A study is underway to compare the objective measurement of reading performance (speed, comprehension) with the patients' subjective evaluation of their ability in comparison to that before their visual impairment.
Ongoing

Last updated: 28/11/2007

Prof. Velma Dobson
The University of Arizona, Department of Ophthalmology and Vision Science, 655 N. Alvernon Way, Suite 108, Tucson, AZ 85711, United States of America
Tel: +1 520 324 3160
Fax: + 1 520 321 3665
Email: vdobson@eyes.arizona.edu
Web: www.eyes.arizona.edu/

Current & recent projects

Early Treatment of Retinopathy of Prematurity (ETROP) Follow-up: Visual Acuity Center (Phase II)
Co-worker(s): Robert Hardy (PI)
Recognition (letter) acuity will be measured by local testers when children reach 4 and 5 years of age. Traveling testers will measure visual acuity and visual field extent when children reach 6 years of age.
Project start date: 30/09/2004
Project end date: 29/09/2009

Amblyopia in Astigmatic Children – Development and Treatment
Co-worker(s): Erin Harvey (PI)
The goals of this study are to characterize vision deficits associated with astigmatism-related amblyopia, to identify factors influencing the development of astigmatism-related amblyopia, and to determine age-specific effects of glasses intervention on astigmatism-related amblyopia.
Project start date: 01/08/2002
Project end date: 31/07/05

Vision in Preschoolers Study: Scientific Advisor
Co-worker(s): Paulette Schmidt (PI)
The goal of this study is to identify effective and cost-efficient methods for identifying which preschool children require full eye examinations.
Project start date: 01/09/2000
Project end date: 31/08/2005

Last updated: 28/11/2007

Dr. Graeme Douglas
Visual Impairment Centre for Teaching and Research (VICTAR), School of Education, University of Birmingham, Edgbaston,
Birmingham, B15 2TT, United Kingdom.
Tel: +44 (0) 121 414 6736
Fax: +44 (0) 121 414 7444
Email: g.g.a.douglas@bham.ac.uk
Web: http://www.education.bham.ac.uk/
Publications

Current & recent projects

Network 1000: Surveying the changing needs and circumstances of visually impaired people - Phase 2
Second phase of the research programme originally commissioned by the Big Lottery Fund in 2004. Phase 2 has been funded by Thomas Pocklington Trust, RNIB and GDBA and aims to further analyse the data gathered in Phase 1 of the project, as well as maintain the Network 1000 sample so that participants can be re-contacted in the future.
Project start date: 04/2007
Project end date: 12/2008

Network 1000: Surveying the changing needs and circumstances of visually impaired people - Phase 1
Research project commissioned by the Big Lottery Fund, with 3 main aims:

To establish a consultation network of 1000 visually impaired people who can be regularly surveyed on a range of issues affecting them;
To provide a network for longitudinal studies enabling comparative data to be evaluated;
To provide statistically useful data on the changing views, experiences and needs of visually impaired people which can be used to influence service development and provision

Project start date: 03/2004
Project end date: 03/2007

Reporting protocols for evaluating eye clinic support services (ECSS)
Investigation of the role of Eye Clinic Support Services (services situated in eye clinics which offer general non-medical support and advice to people with visual impairment)
Project start date: 2006
Project end date: 2007

The needs of older adults with acquired hearing and sight loss
Co-worker(s): Liz Hodges
A scoping study to investigate the recent literature in the area of acquired hearing and sight loss in older people. More specifically, the study brief had two broad objectives:

To give an overview of the key recent published literature in the
UK and identify ongoing relevant work in the area of combined
hearing and sight loss.
To make recommendations for future work – which might
include development work and/or further research.

Project start date: 2005
Project end date: 2005

Last updated: 03/12/2007