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Current Research Projects
Gary S. Rubin, PhD
Helen Keller Professor of Ophthalmology
UCL Institute of Ophthalmology
Low Vision Patient Day
7 June 2014
Topics
• Basic Research Service Delivery
• New Devices Training
• Two projects undertaken with colleagues from other parts of the University (Dept of Transportation Engineering) and colleagues from other universities (School of Architecture, Kingston University
Is there Brain Remapping in Macular Disease? (Baseler, 2007)
• Specific areas of the brain process information from specific areas of the visual field
• AMD central scotoma silent areas of the brain
• Do these silent areas regain function?
• For vision – No
• For other senses – maybe Yes
Response of Area V1
Silent brain areas before and after
Clinical Predictors of Reading Speed in AMD (Rubin & Feely, 2009)
• Visual acuity does NOT predict reading speed in patients with AMD
Clinical Predictors of Reading Speed in AMD (Rubin & Feely, 2009)
• Visual acuity does NOT predict reading speed in patients with AMD
• Fixation stability and size of forward saccades account for 74% of variance.
Reading Speed (words/min)
Scanning Laser Ophthalmoscope
Scotoma Map
Replacing the SLO? Nidek MP-1
Compensation for Fixation Instability Improves Reading Speed (Macedo, 2013)
No Comp
Partial Comp
Full Comp
Over Comp0
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ad
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RSVP Reading
Once
RSVP Reading
upon
a
RSVP Reading
time
RSVP Reading
there
RSVP Reading
lived
RSVP Reading
upon a time there lived a
RSVP Reading
Once a time there a vain
RSVP Reading
Emperor.
RSVP Reading
RSVP Improves reading Speed
Normal Vision
Opaque Media
Peripheral Loss
Central Loss0
50
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Re
ad
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Training Possibilities
Eccentric Viewing Eye Movement Training
Perceptual Learning
Electronic Head-Mounted Devices
• Portable• Cosmetically
acceptable• Lightweight• Multipurpose• Affordable (good
value for money)• Commercial support
The ultimate HMD
Electronic Magnification Devices: 1990
Low Vision Enhancement System - LVES
Electronic Magnification Devices: 2001
Jordy®
Reading Performance with Devices
The Demise of Jordy and His Friends
Portable Electronic Low Vision Aids
PELVAs
• Pros– Less expensive (<£400)– Smartphone platform– Battery powered– Light and compact
• Cons– Limited field of view– Limited magnification
• Studies in progress
Implantable Miniature Telescope (IMT)
UK Clinical Trial of IMT (Dunbar, 2010)
• Prospective open label trial of 3x IMT at 4 UK centers
• IMT implanted in better eye of 17 patients• Followed by 12-week rehab course• Results
– 3 line improvement in VA– Contrast sensitivity reduced by 0.4 logCS– Maximum reading rate improved by 10 words/min– Self-reported visual disability (Massof AI) improved by
0.6 logit (equiv to 4 lines of VA)
Retinal Prostheses – ‘Bionic Eye’
• About 10 projects worldwide• Mostly epi-retinal; some sub-
retinal• Well tolerated and apparently
safe• Also optic nerve and cortical
prostheses• Initially, low resolution
– 20 electrodes max due to safety concerns
Winter, et al (2007)
Argus II – Second Sight (California)
Argus II – Second Sight (California)
• Epi-retinal 60 electrode array• Implanted in about two dozen patients worldwide (12 in
UK; 8 Moorfields)• Retinitis pigmentosa with light perception or worse• Outcome measures
– Grating acuity– Phosphene projection– Letter recognition– Mobility
Follow a white line on a black background
Find a white door on a black wall
A Sampler of Clinical Trials Underway
• Impact of LV rehab in patients with diabetic eye disease (Dunbar, 2008-2011)
• Eccentric Fixation From Enhanced Clinical Training, (EFFECT): A Randomised Controlled Trial for Patients with AMD (Rubin, 2011-2013)
• Depression in Visual Impairment Trial (DEPVIT; Margrain, 2011-2013)
• The impact of timely emotional support on the quality of life of blind and partially sighted people (Afsani, 2011-2013)
Summary and Conclusions
• Substantial growth in low vision research during the past 10 years
• Shifting emphasis from head-mounted low vision magnifier to portable hand-held electronic magnifier
• New initiatives in service delivery showing great promise
• Profusion of new outcome measures• Building momentum in establishing a sound
evidence base for the effectiveness of low vision rehabilitation
• Still plenty of additional work to be done!
Acknowledgements
• Collaborators– Louise Culham - Moorfields Eye Hospital– Alan Bird - Moorfields Eye Hospital– Liz Pearce – Moorfields Eye Hospital– Peter Bex – Fred Fitzke
• Postdocs and Students– Michael Crossland– Stamatina Kabanarou – Caren Bellmann– Angela Rees – Thomas Butt– Radhika Gulati– Hannah Dunbar– Anthony Chabra
• Research Assistants– Eugeniu Dinu– Mary Feely– Hannah Roche
• Funding– Wellcome Trust– National Institute of Health
Research– Guide Dogs for the Blind
Association– Macular Disease Society– European Commission– Fight for Sight– Special Trustees of Moorfields
Eye Hospital– Garfield Weston Foundation– Friends of Moorfields Eye
Hospital