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References from
Ellerbrock Talk On Reading with Central Scotomas
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Outline of Talk
READING WITH CENTRAL SCOTOMAS, TRAINING AND IMPLICATIONS OF CURRENT
RESEARCH
William F. O’Connell O.D., F.A.A.O.
Lighthouse International
SUNY, College of Optometry
Michael Fischer O.D., F.A.A.O.
Lighthouse International
Near Visual Acuity Charts
Lighthouse ETDRS
GAME
Number
Letter
Continuous Text - Adult / Child
MNRead
Prismatic Displacement Historical Perspective
Romayananda et. al.
Onufryk
Lighthouse
Bailey
Verezen et. al.
Where is Scotoma Moved
Research by Ron Schuchard using SLO
31.7% move scotoma to left
49% move scotoma to Right
45.6% move scotoma up
21% move scotoma down
Eccentricity Vs. V.A.
Weymouth 1958
1 Degree = approx 20/30
5 Degrees = approx. 20/100
10 degrees = approx 20/200
Which Eyes do not develop PRL?
Ron Schuchard
Worse eye often does not develop PRL
Only 4.4% of patients on initial examination with SLO did not have
PRL.
Some patient have 2 PRL’s - Bright vs. Dim illumination.
Prevalence of Scotomas
82.5% of LV Patients have Central Scotoma
90% Macular Scotoma
R.S.V.P.
Does it currently have practical applications?
Do readers enjoy using R.S.V.P.?
Computer needed.
What are patient’s objectons to using it.
What can be done to make it more enjoyable?
R.S.V.P. Software
V.I.P.
Vortex
V.I.P.
J. Bliss
System Price $2800
Software only $900
E-Z VIP $695
V.I.P.
Easy to use interface.
Numeric Keypad Control
Speech backup.
Difficult to Customize
Difficult to set exact WPM
Not a Good Research Tool.
VORTEX
Makes any Wordprocessor file R.S.V.P.
Can Set WPM to any exact Level
Good Research Tool
End Users should have good computer knowledge.
No Speech Backup.
ECCENTRIC VIEWING
CANDIDATE SELECTION
DISTANCE ACUITY
CONSISTENT MISSES ON DISTANCE CHART
NEAR ACUITY - LETTER VS. WORD VS. TEXT
CONTRAST SENSITIVITY
AMSLER GRID
AGE OF ONSET
Proportion of patients requiring training appears to be related to
increasing age.
Nursing home patients - clinical observations.
DIAGNOSIS
MACULAR DEGENERATION
DIABETIC RETINOPATHY
TOXOPLASMOSIS
STARGARDT'S DISEASE
AMSLER GRID
AMSLER GRID INTERPRETATION
OFF CENTER SCOTOMA
CENTRAL SCOTOMA
NO SCOTOMA SEEN
DISTORTION
WHAT DOES A SCOTOMA LOOK LIKE?
USING YOUR HEAD (FACE)
LITERATURE REVIEW
TRAINING - KEEP IT SIMPLE
STEP ONE - DISTANCE - AWARENESS
STEP TWO -CONTROL START BY PURPOSELY
PLACING THE SCOTOMA
STEP THREE - FINDING THE BEST ECCENTRIC VIEWING POINT
STEP FOUR - MAINTAINING THE ECCENTRIC VIEWING POINT
STEP FIVE -SACCADIC EYE MOVEMENTS
CAVEAT
FOR TRAVEL AND MOBILITY PURPOSES -
ONLY A VERTICAL ECCENTRIC VIEWING POINT IS RECOMMENDED - REGARDLESS
OF WHICH DIRECTION WORKS BEST
NEAR TRAINING
GOAL - READING CONTINUOUS TEXT
VERTICAL ECCENTRIC VIEWING
USE OF FIXATION AIDES - TYPOSCOPE
THE MITCH MILLER TECHNIQUE
PRACTICE WITH SINGLE LETTERS
WORD GAMES - THE ART AND PRACTICE OF LOW VISION
PRACTICE WITH SINGLE WORDS - PROGRESSIVE DIFFICULTY
SACCADIC EYE Movement Training
LOSING YOUR PLACE
LET YOUR FINGERS
DO THE WALKING
LARGE PRINT CONTINUOUS TEXT
READERS DIGEST
THE WORLD AT LARGE
N.Y. TIMES
YOUNG & ALIVE
IN OFFICE TRAINING VS. AT HOME TRAINING
COST
EFFECTIVENESS
PREPARING THE PATIENTS
ECCENTRIC VIEWING
"WHO NEEDS IT?"
AGE OF ONSET
Not just chronological age
Mental ability
USING YOUR HEAD (FACE)
PATIENTS MAY BE AWARE OF
MISSING FEATURES LOW CONTRAST
TRAINING KEEP IT SIMPLE
PREPARING THE PATIENTS
READING TESTS
GRAY ORAL READING TEST
REAL TEXT PASSAGES
FOUR FORMS
LEVELS FOR GRADES 1 THROUGH ADULT
PRINT SIZE IS 12 POINT
PEPPER TEST - FOR LOW VISION
VARIABLE POINT SIZES - 8, 12 , 14 , 18, 24 POINT
NOT LIKE “REAL” READING
WIDTH OF PAGE MUCH WIDER THAN NORMAL
HOW DO YOU MEASURE SUCCESS ?
PATIENT SATISFACTION
ACTUAL READING ABILITY
TACHISTOSCOPIC TESTING
STANDARDIZED READING TESTS
ARMD
Accounts for roughly 13% of patients registered as legally blind.
ECCENTRIC VIEWING
THE PATIENT REALIZES THAT THEY ARE LOOKING AWAY IN ORDER TO SEE THE
TARGET.
ECCENTRIC FIXATION
THE PATIENT HAS THE SENSATION OF LOOKING DIRECTLY AT THE FIXATION TARGET.
SCOTOMAS
are associated with 64% of reading speed variations
Legge and Ross
Preferred Retinal Locus (PRL)
Is locating it automatic or not?
Research - seems to indicate that it is.
Clinical experience - with many patients would indicate that it is
not.
CLINICAL ASSESSMENT
Does the patient look at you during the history?
Relative difficulty of Continuous Text VS. Single Letters / Numbers
/ Words
Visual Acuity - Is Chart Jumping Necessary?
Does Patient regularly miss certain letters - left right, center?
Amsler Grid
VISUAL ACUITY MEASUREMENT
VISUAL ACUITY MEASUREMENT
IMPORTANT CLINICAL TEST
DESIGNS FOR VISION CHART
moving the chart may elicit the desired response.
which directions work best. shift strategies, instead
of moving the chart, have the patient look in the
direction indicated by the chart jumping.
ETDRS CHART
An ETDRS type chart , such as the Lighthouse acuity chart
is preferred FOR BETTER ACUITIES because
of the consistency in figure spacing as the letters or numbers get smaller.
VISUAL ACUITY MEASUREMENT
take time during testing to discuss the way the patient reads the chart
This is the first opportunity to discuss eccentric viewing.
AMSLER GRID - reliable?
> 65% of Patients place their PRL at the center of the grid - appears
as a paracentral scotoma when central.
Unless the exact location of the PRL is known, it is impossible to
judge the size and shape of the scotoma.
Larger Scotomas - more likely to be detected.
AMSLER GRID
Has SIGNIFICANT shortcomings.
Perceptual Filling
sensitivity of both standard and threshold Amsler Grid testing
- very low, fail to detect almost half of scotomas.
when scotomas are detected, the full extent of the scotoma is frequently
understated.
AMSLER GRID
Several means exist to try to elicit more accurate responses to this
test.
binocular presentation first,
threshold illumination techniques,
Amsler grids of different colors, particularly red,
lower contrast grid.
Schuchard, Fletcher.
Scotomas that appear to be to the right of fixation (PRL) are logically
going to be more problematic.
Scotoma - PRL - locations versus reading difficulties.
CONTRAST SENSITIVITY
For Normal subjects - tenfold drops of contrast reduced reading speed
by a factor of less than two.
For visually impaired readers, the effect of contrast is far greater,
with many fast readers unable to read at all if the contrast fell below
30%. Rubin
Contrast Polarity
With CLOUDY MEDIA - reversed contrast was generally preferred.
Other low vision problems show a slight preference for reversed contrast.
Normally sighted subjects appear to read about 10% faster with normal
black on white lettering
Single Symbol vs. Single word vs. Continuous text
If the patients goals include reading - Continuous text acuity should
be performed.
Optimum test is to have the patient read the types of materials they
desire to read on a daily basis.
PASTPOINTING
quick test
have patient point to a penlight held at 40 cm. Patient
can self correct so have this done quickly as in hitting the light or to
avoid compensating movements...
Tangent Screen
More Accurate than Amsler Grid
Still not accurate based upon SLO studies.
SLO - Scanning Laser Ophthalmoscope
SLO studies - scotomas range from 3 to 30 degrees larger than
those measured on a tangent screen,
positional errors > 5 degrees. Shapes of scotomas agree
well.
All field tests are limited at best in giving field information
reliable enough to base eccentric viewing training upon.
TRAINING ECCENTRIC VIEWING - Patient selection
motivation
awareness of scotoma
ability to remember
ability to follow complex instructions
ability to understand the concept
TRAINING ECCENTRIC VIEWING
Prismatic Displacement
CAN WE FORCE ECCENTRIC VIEWING WITH PRISMATIC DISPLACEMENT?
HOW LONG DOES THE EFFECT LAST?
CAN IT BE USED AS A TRAINING ADJUNCT?
TRAINING ECCENTRIC VIEWING
Blind Spot Awareness
Blind Spot Control
Direction
Degree
BLIND SPOT AWARENESS
Face observation - sometimes the human face will be helpful as details
of the face are often missing. It also provides a target of very
low contrast.
BLIND SPOT CONTROL
- Once a patient is aware of the scotoma, it is important to begin
to reinforce it’s use and position by having the patient make things disappear.
conscious control of the scotoma will be strengthened, although
the visual improvement desired will not be evident.
ECCENTRIC VIEWING DIRECTION AND DEGREE
General Technique - patient sits a comfortable
distance from an uncluttered wall with a single suprathreshold size
number taped on it.
They look slowly in 8 directions
Find the best image - how far from target?
Record results and use in practice.
VERTICAL VS. HORIZONTAL ECCENTRIC Viewing
Some clinicians feel that vertical viewing points should be used routinely
unless there is a dramatic difference between horizontal and vertical results.
This is based on the practical safety problems encountered when patients
cross streets.
TRAINING TECHNIQUES FOR ECCENTRIC VIEWING
BLIND SPOT AWARENESS
BLIND SPOT CONTROL
E. V. DIRECTION AND DEGREE
OCULOMOTOR SKILLS
PASTPOINTING
SACCADES AND PURSUITS
PLEIOPTICS
TRAINING ECCENTRIC VIEWING
EYE HAND COORDINATION
Postpointing
pouring, filling in circles, Michigan tracking series, Marsden ball.
eye hand re-coordination training helps define the new PRL in
relation to the patient's body.
TRAINING ECCENTRIC VIEWING
SACCADE AND PURSUIT MOVEMENTS
Fixation
Localization
Scanning
TRAINING E. V. Guided Practice Techniques
Saccade Training
Clock Directions
Rotator - tracking, fixation and pursuits
Pegboard Rotator - eye hand coord.
Slide Projector
Marsden Ball
Wayne Saccadic Fixator
DIRECTION OF ECCENTRICITY
Peli's work confirms clinical experience that their are fewer
training problems when the PRL is not along the axis of image motion.
This means vertical eccentric viewing is preferable...
Goodrich
has indicated that, for English at least, the top half of letters hold
more information for identification than do the bottoms.
Is it easier to read this particular line?
Is it easier to read this particular line?
READING AS TRAINING
LARGE PRINT
MAGNIFICATION
CCTV
TRAINING TECHNIQUES FOR READING
READING - IS IT THE BEST TRAINING TECHNIQUE?
DIRECTION OF ECCENTRICITY
THE ENGLISH ALPHABET
CCTV
LARGE PRINT
SPECIALIZED TRAINING SHEETS
SINGLE LETTERS/NUMBERS
SMALL WORDS
NONSENSE - RANDOM WORDS
USE OF FINGERS / FIXATION AIDS
Vertical Eccentric Viewing
lines above and below letters, words, and continuous text
readily available in Freeman and Jose's text,
may be produced easily on the computer.
USE OF FINGERS, FIXATION AIDS
difficulty with pastpointing, localization, and saccades,
ruler, typoscope or fingers
to prevent losing place,
locating the beginning of the next line.
WHICH DEVICES TO USE FOR MAGNIFICATION DURING TRAINING
WEAKER AND LARGE PRINT
FULL STRENGTH WITH SMALL PRINT
CCTV
SUCCESS ORIENTED
Give the patient achievable goals.
Reduce frustration
PROBLEMS AND SOLUTIONS
LOSING PLACE - use fingers
SKIPPING LINES - use marker finger at beginning of line
LOCKING ON SCOTOMA - spell - skip
COMMON AND UNAVOIDABLE PROBLEMS
CONSISTENT ERRORS
TRYING TO READ TOO FAST
LACK OF COMPREHENSION
HEADACHE - EYESTRAIN - DIZZINESS
FATIGUE
FRUSTRATION
LACK OF MOTIVATION
DEALING WITH PATIENT PROBLEMS
LOCKING ON THE BLIND SPOT
CONSISTENT ERRORS
TRYING TO READ TOO FAST
LACK OF COMPREHENSION
HEADACHE / EYEACHE / DIZZINESS
FATIGUE
FRUSTRATION
GETTING STUCK - LOCKING ON THE BLIND SPOT -
Pt. should not get stuck and frustrated on a single difficult
word.
1) try to spell the word ,
2) skip the word and move on.
ERRORS OF A CONSISTENT NATURE
consistently miss the beginning, end , or center of words,
Often, simple discussion of the problem is sufficient to begin the
process of learning how to relocate the scotoma and avoid this problem.
PATIENT TRYING TO READ TOO FAST
numerous mistakes.
remind the patient - of need to begin more slowly
will build speed slowly.
training option - lists of random words
LACK OF COMPREHENSION
frequent patient complaint
reassurance
learning process
comprehension will improve.
HEADACHE / EYEACHE / DIZZINESS / FATIGUE
common and unavoidable.
warn patients - will occur
reassure - will not harm them
take breaks
FRUSTRATION or LACK of apparent MOTIVATION -
goal reassessment, lowering the goals, at least temporarily.
read for necessity - bills, mail etc.
IN OFFICE VS HOME TRAINING
COST
SUCCESS RATES
NEED FOR RESEARCH
THE FUTURE OF ECCENTRIC VIEWING
IMAGE REMAPPING - RELOCATION
WILL PERFORMANCE EXCEED ECCENTRIC VIEWING?
LASER SCANNING OPHTHALMOSCOPE
IN ASSESSMENT, TRAINING AND SELECTING
EV POINTS
HANDOUTS
ART AND PRACTICE
USING YOUR COMPUTER
REFERENCES
The Art and Practice of Low Vision
Remediation and Management of Low Vision
Adapting Dynamic Text Presentation (RSVP)
variable rate control
elicited sequential presentation
Computer Based Reading - Making the Interface Transparent
many older patients resist the concept of using a computer
need a reading machine that is easy to use
Kurzweil currently has simplest interface - but no RSVP
one button operation with toggle for speed / elicited presentation
The technology is here - we just have to make it appealing
Scrolled Vs. R.S.V.P. Reading Rates
CCTV Research
Goodrich - reading rates nearly double
reading duration nearly doubled
reading efficiency - rate X duration = 1.6X Higher
Suprathreshold magnifications
2.5 to 8x Threshold yielded maximum reading rates
requires CCTV or Computer for most patients
rates effected by scrolled presentation at these magnifications
Accuracy of Optical Character Recognition
best is Kurzweil
Xerox Textbridge and Caere Omnipage lag somewhat
accuracy for speech somewhat less important than for visual reading
Number of Letters Masked Is More Important
Reading with central field loss: number of letters masked is more important
than the size of the mask in degrees.
until mask size is quite large (> or = -7.5 degrees) and number of
letters masked from view is more than seven. Fine EM, Rubin GS Vision Res
1999 Feb;39(4):747-56
Use of Several Preferred Retinal Loci
Combined use of several preferred retinal loci in patients with macular
disorders when reading single words.- Duret F, Issenhuth M, Safran AB
Eventually, they could localize their PRL, describe their specific
functions, and switch at will between them. Vision Res 1999 Feb;39(4):873-9
Attending to the Right Is Better
Reading with simulated scotomas: attending to the right is better than
attending to the left. - Fine EM, Rubin GS
data imply that patients would be better off with PRL to the right
of their scotoma than to the left for the purposes of reading. Vision Res
1999 Mar;39(5):1039-48
Can we train an eccentric retinal locus?
Location and stability of a new eccentric retinal locus suitable for
reading through training. -Nilsson UL, Frennesson C, Nilsson SE
indicate that an eccentric PRL favorable for effective reading can
be established through training
fairly low number of training sessions is required. Optom Vis Sci 1998
Dec;75(12):873-8
Minute Scotomas Can Be Detected With the SLO.
Minute scotomas (diameter = 0.3 degree) can be detected with the SLO.
All patients showed objective improvement of their field defect up to 6
months, even when this was not noted by the patient or thought to be due
to habituation. Ophthalmologe 1999 May;96(5):325-31
Small scotomas can dramatically reduce reading performance. Ehrt O,
Tavcar I, Eckl-Titz G
CFL Increases Saccades
Loss of the central visual field increases number of saccades because
the number of digits perceived during each fixation decreases.
High number of regressions may be caused by shift of center of
fixation following paracentral scotoma.
Saccades directed to scotoma must be corrected due to failure of exact
positioning. Rohrschneider K, Bethke-Jaenicke C, Becker M, Kruse FE, Blankenagel
A, Volcker HE Ger J Ophthalmol 1996 Sep;5(5):300-7
Fixation With the Scotoma to the Right
20/80 to 20/200 visual acuity. / 41 eyes of 35 patients with GA - 10
eyes of 5 patients with Stargardt’s
preference for fixation with scotoma to the right in eyes with GA.
Stargardt disease - different strategies for fixation, perhaps due
to subclinical pathology adjacent.
The size of the atrophic area in GA plays the predominant role in reading
rate. Sunness JS, Applegate CA, Haselwood D, Rubin Ophthalmology 1996 Sep;103(9):1458-66
Predictors of Magnifier-aided Reading Speed
best predictor of magnifier-aided reading speed was score on
standardized reading test - 79.7% of variance.
43.7% of the variance by age / 42.3% by magnifier
type.
Snellen acuity, central visual field status, ocular media not significantly
correlated with magnifier reading speed.
conclude that a standardized clinical reading test can give a
valid prediction of the reading speed a low-vision patient is likely to
achieve with a magnifier. Psychophysics of reading--XIII. in low vision.
- Ahn SJ, Legge GE Vision Res 1995 Jul;35(13):1931-8
Spatial Remapping Study - Small Scotomas
letter size for optimal reading rate increases systematically with
scotoma size.
optimal reading rate decreased more or less linearly as the scotoma
size increased.
duration of text presentation irrelevant scotoma size.
spatial remapping produced small but significant increases in reading
rate in 4 and 8 degree scotomas.
average reading rates were faster for the young Wensveen JM, Bedell
HE, Loshin DS Optom Vis Sci 1995 Feb;72(2):100-14
Training Success
establish the most suitable area for eccentric viewing
train patients to use eccentric viewing Using a computer and video
display based system, software
30 min of testing, 2.6 + or - 0.69 one-hour training sessions,
reading texts with high plus at close distance
reading speed of 58.9 + or - 19.7 words/min, significantly higher than
initial speed 11.5 + or - 4.5 words/min. Frennesson C, Jakobsson P, Nilsson
UL Doc Ophthalmol 1995;91(1):9-16
Low vision reading with sequential word presentation.
results indicate that inefficient eye movements account for only part
of the reduction in reading speed caused by CFL.
An additional and potentially more important factor is the limited
rate at which peripheral retina can perform the pattern decoding tasks
required for reading. Rubin GS, Turano K Vision Res 1994 Jul;34(13):1723-33
Systematic Location for the Pseudo-fovea
most cases fixation was located on the left or inferior part of the
visual field relative to the scotoma.
inferior visual field is used is coherent with the notion that the
lower visual field is important for locomotion.
preferential use of the left field appears contradictory with data
showing superiority of visual faculties in the right visual field. Vision
Res 1993 Jun;33(9):1271-9 Guez JE, Le Gargasson JF, Rigaudiere F, O'Regan
JK
Four Different Visual Factors That Significantly Affect Reading Rate:
(1) acuity reserve print size relative to acuity threshold
(2) contrast reserve contrast relative to contrast thresh.
(3) field of view number of letters visible, and
(4) in cases of maculopathy, central scotoma size.
Optom Vis Sci 1993 Jan;70(1):54-65 Whittaker SG, Lovie-Kitchin J
Reading without saccadic eye movements.
minimum word duration required for accurate oral reading averaged 69.4
msec and was not reduced by increasing ISI.
We interpret these results as an indication that the programming and
execution of saccadic eye movements impose an upper limit on conventional
reading speed. Rubin GS, Turano K Vision Res 1992 May;32(5):895-902
Visual span in normal
and low vision.
visual span in reading is the number of characters that can be recognized
at a glance.
hypothesis attributes reading deficits in low vision to a reduction
in the visual span.
RSVP -strong dependence of reading time on word length, as expected
from reduced visual spans. Vision Res 1997 Jul;37(14):1999-2010 Legge GE,
Ahn SJ, Klitz TS, Luebker A Psychophysics of reading--XVI
Low-vision performance with four types of electronically magnified
text.
central-field loss = CFL, central fields intact= CFI
CFI group read significantly faster with DRIFT (43%) and RSVP (38%).
CFL group showed no significant differences in reading speed for the
four methods. Harland S, Legge GE, Luebker Optom Vis Sci 1998 Mar;75(3):183-90
Psychophysics of reading. XVII. -
Reading unspaced text: implications for theories of reading eye movements
We conclude that the current tendency to emphasize spaces as guides
to reading eye movements must be reconsidered.
Words, not spaces, may serve as the perceptual units that guide the
line of sight through the text. Epelboim J, Booth JR, Steinman Vision Res
1994 Jul;34(13):1735-66
Page Navigation Problem in Using Magnifiers
magnifier's field of view - often few letters at a time.
Page navigation - moving the magnifier from word to word, and
from line end to beginning of the next line.
Page navigation takes time and reduces reading speed.
the window width requirements for reading are 10 characters for CCTV
vs 5.2 characters for drifting-text for 85% of maximum reading speed
Beckmann PJ, Legge GE Vision Res 1996 Nov;36(22):3723-33 Psychophysics
of reading--XIV.
The.
Eye movements during reading and scanning are different
our results show that eye movements are not guided by a global strategy
and local tactics, but by immediate processing demands. Rayner K, Fischer
MH Percept Psychophys 1996 Jul;58(5):734-47
A comparison of word recognition and reading performance in foveal
and peripheral vision.
The results suggest that word recognition is the same across the visual
field apart from change in scale,
periphery is inferior to the fovea at interpreting sentences with meaning.
Latham K, Whitaker D Vision Res 1996 Sep;36(17):2665-74
Sloan M Acuity Was a Better Predictor of Optimal Character Size
...than Snellen acuity, accounting for 72% of the variance. Legge GE,
Rubin GS, Pelli DG, Schleske MM Vision Res 1985;25(2):253-65 Psychophysics
of reading--II.
Low vision.
Reading Rates Increase As the Field of View Increases
The necessary field of view to read with an optimal stand magnifier.
- Fine EM, Kirschen MP, Peli E. J Am Optom Assoc 1996 Jul;67(7):382-9
This study confirms reports that reading rates increase as the
field of view increases when reading from a page of text.
The Role of Context in Reading With Central Field Loss.
reduced reliance on context cannot explain the slower reading rates
of people with CFL. - Fine EM, Peli E Optom Vis Sci 1996 Aug;73(8):533-9
Eccentric Fixation With Macular Scotoma
Fixation variability increased with scotoma size
abrupt rise when diameters exceeded 20 degrees .
39% of subjects two or more distinct PRL
Multiple PRL were more likely if scotoma >20 d.
Reasonably steady fixation when central scotoma sizes
are <20 degrees. Whittaker SG, Budd J, Cummings Invest Ophthalmol
Vis Sci 1988 Feb;29(2):268-78
The Role of Contrast
in Normal Vision.
Reading rates highest (350 wpm) letters 0.25 d to 2 d.
reading very tolerant to contrast reduction--1 degree letters, rate
decreased by less than factor of two for tenfold contrast reduction. Similar
for white-on-black.
Rate declined more rapidly - very small (< 0.25 degree) and very
large (>2 degrees) letters.
LV require large characters, so high contrast is particularly important
for them. Legge GE, Rubin GS, Luebker A
Designing an interface to optimize reading with small display windows.
(a) Though RSVP is disliked by readers, the present methods of
allowing self-pacing and regressions in RSVP are efficient and feasible,
unlike earlier tested methods;
(b) slower reading in RSVP should be achieved by increasing pauses
between sentences or by repeating sentences, not by decreasing the presentation
rate within a sentence; Rahman T, Muter P Hum Factors 1999 Mar;41(1):106-17
The effect of print size on reading speed in normal peripheral vision.
print size is not the only factor limiting maximum reading speed in
normal peripheral vision. Chung ST, Mansfield JS, Legge GE Vision Res 1998
Oct;38(19):2949-62 Psychophysics of reading. XVIII. -
Benefits of RSVP over scrolled text vary with letter size
subjects with normal vision read faster with RSVP for all text sizes.
Low vision subjects showed no benefit of RSVP until the text was at
least 8x acuity threshold.
great deal of variability within the low vision group,
for a small number of subjects (25%), reading was faster from the scrolled
than from the RSVP display.
Fine EM, Peli E Optom Vis Sci 1998 Mar;75(3):191-6
Simulated cataract does not reduce the benefit of RSVP.
benefits of RSVP are not reduced with reduced acuity and contrast sensitivity,
there are age-related changes in reading rates from dynamic text displays
not related to acuity. Fine EM, Peli E, Reeves A Vision Res 1997 Sep;37(18):2639-47
Sustained focal attention and peripheral letter recognition
choice of a PRL for eccentric viewing can be limited by an attentional
factor that is unrelated to the eye disease. Mackeben M Spat Vis 1999;12(1):51-72
Reflections of PRL Research on future reading training techniques
No Study has shown to date the EV Training has developed new PRL’s
at different retinal locations
system strongly prefers use the PRL for all visual tasks.
Some L.V. patients have difficulty learning to use an eccentric point
even when PRL is inappropriate to task.
Most strong LV devices are monocular - careful not to use the supressed
eye - may be better VA eye
Eccentric viewing training improves performance - why? More research
is needed. Vision 99 Schuchard, R
If there is no print size limit do patients with CFL need training?
Studies showed that even when motor demands of standard optical devices
are removed (with RSVP) and magnification well above threshold can be supplied,
that low vision readers demonstrate increases in reading rate for RSVP
text presentation with practice. Vision 99 - Aquilante / Yager / Morris
Reading with Elicited Sequential Presentation, a varient of RSVP
No benefit if reading rates with RSVP are 133 wmp or greater.
slower readers benefit with ESP - yielding reading speeds equivalent
to CCTV reading for those subjects. Vision 99 - Arditi
Quantifying the Benefits of CCTV Versus Optical Aids
Speed, Duration, and Productivity (speed times duration)
CCTV Moderate Speed Increase, Greater Duration increase
Productivity significantly increased.
Vision 99 - Goodrich
Electronic Reading: Future Clinical Applications
Methods need to be developed for patients to acquire the materials
they want to read in the appropriate form, and to control the presentation
themselves.
MY NOTE - what about context sensitive RSVP that would present longer
words for longer periods based upon a researched algorithym Vision 99 -
Yager
Current Trends and Clinical Tools in the Instruction of Reading
Visual Eficiency scale - Barraga (APH)
Pepper Visual Skills for reading test
Morgan L.V. Reading Comprehension assessment
MnRead Charts - 19 sentences from 1.3 to -0.5 logMAR
LUVWriting Assessment
Warren Pre-Reading and Writing Excercises
McGill L.V. Manual - works w Visual Efficiency scale
SRA Reading Laboratory Kit - Vision 99 - Watson
Outline of Technology Talk
HIGH TECH / COMPUTER / VIDEO APPLICATIONS IN LOW VISION
William F. O'Connell O.D., F.A.A.O.
Director, Low Vision Services Lighthouse Int’l. , Hudson Valley Region
A brief history of technology in Low Vision and Blind
Rehabilitation
Technologies that Failed: WHY?
Mowat Sensor / Laser Cane / Sonicguide
LVES
Technology that advanced
Braille ‘n’ Speak, Braille printers
Kurzweil reading machine
CCTV’s / V-Max / Jordy
THE SHORT HISTORY OF THE PERSONAL COMPUTER
APPLE / INTEL / HEWLETT - PACKARD
BILL GATES / MICROSOFT
MOORE’S LAW
KURZWEIL
OUTPUT
MONITORS AND DISPLAYS
LARGE DISPLAYS
LIQUID CRYSTAL DISPLAYS
HEADBORNE
VIRTUAL
REALITY
DISPLAYS
CCTV Vs. COMPUTER
RSVP
Image Remapping and Relocation
Text Display modes and reading speed
Speech Backup
SOFTWARE PRINT MAGNIFICATION SYSTEMS
Zoom Text
VisAbility
LP Windows
Loupe
MaGic
Windows 98 Magnifier
SPEECH OUTPUT
FLEXTALK -
DECTalk - DEC
KURZWEIL
Large Print + Speech
Zoomtext Xtra
Speech Products for Windows
Screen Review Utilities
Jaws (Henter-Joyce)
Window-Eyes (G-W)
Braille Products
Braille ‘n’ Speak -
Portable Note Taker
Braille Printers
Braille Displays
Web Browsers
VIPinfoNet Browser
IBM - Home Page Reader for Windows
INTERFACES / INPUT
KEYBOARDS
OF MICE AND MEN
WHY SPEECH INPUT
IS THE HOLY GRAIL
Scanners
FLATBED / PAPERPORT / Hand Held
OPTICAL CHARACTER RECOGNITION SYSTEMS
Caere - Omni Page
Xerox - Textbridge
Both Now Scansoft
Text to Speech Systems
VIP
Zoom Text
Kurzweil / READING EDGE
Scanning Text to Speech
Jbliss Imaging System Products
ezVIP Plus Reading System V2.0
VIPInfoSoft V2.6
VIPinfoNet Browser V1.2
Kurzweil Omni
Zoomtext Level 3 - due ???
Speech Commands / RECOGNITION
Technical Difficulties
Why It Will Be Successful
Microsoft - Speech in its future?
New Speech Recognition Products
JawBone - Combination of Jaws for Windows and Dragon Naturally Speaking
Sherpa - Speech Recognition + Repetitive Tasks
Lernout & Hauspie - L&H - Purchased Kurzweil Educational Systems
Speech Input Products
L&H Voice Xpress™ Professional plus a digital voice recorder lets
you dictate on the go. (Kurzweil VoicePro) Legal / Medicine
Versions
Dragon Naturally Speaking (Now L&H)
FreeSpeech 98 (Phillips)
ViaVoice; Voice Type; Simp
ly Speaking Gold (IBM)
In Cube Voice Command (Command Corp )
Voice Pilot 3.5 (Voice Pilot Technologies)
Language Translators
Soon this will interface with speech input for instant vocal translation.
(Kurzweil)
Microsoft Web Site www.microsoft.com/enable
Technology in Orientation and Mobility
GUIDANCE SYSTEMS
HAZARD AVOIDANCE SYSTEMS
cane travel
dogs
Orientation
GLOBAL POSITIONING SYSTEMS - mapping, position, directions
NAVIGATION SYSTEMS
GPS gets Small-but does it Speak? Guide Dogs - Irreplaceable???
Video Magnification / Display Units
Zoom lenses
display units
weight and resolution
Where LVES went wrong
Ignoring reality / over - engineered
where V-Max / Jordy needs to go
Video magnification units of the future
Flat Screen Displays
Head Mounted Displays
Heads - up Displays
Portable Systems
Automatic Scanning /
Scrolling / RSVP
Current State of the Art
Jordy
NuVision
WHAT THE FUTURE HOLDS
MINIATURIZATION
Moore’s Law
ARTIFICIAL INTELLIGENCE
DESCRIPTIVE SYSTEMS
ARTIFICIAL VISION
Cortical Implants
Retinal Implants
Medical Rehabilitation Advances
SLO
Nanotubes - a 3rd Dimension For Moore’s Law
Tubes made of Carbon 60 will eventually enable chip manufacturers to
enter the third dimension. Other uses involve high resolution Flat
Screen Displays.
Currently up to 1mm long
Nanoprobes
No the Borg have not attacked us!
Currently, a marker system for
finding and marking particular
blood borne cells
Hyperlinking to Resources in Low Vision
The Internet holds vast potential as a reference source for both Low
Vision Clinicians and their patients..
Large Print Pages - No Frames/Pics
NFB Newsline
http://www.nfb.org/newsline.htm
Newspapers sent electronically to NFB sites where they can be accessed
by phone by voice.
HOW MUCH SHOULD TECHNOLOGY COST?
MASS MERCHANDISING
SPECIALTY BLIND PRODUCTS
WHY THE TWO WILL CONVERGE
Star Trek’s Contributions to Low Vision
VISOR (Visual Input Sensory Optical Reflector)
OUR INFORMATION PAGES
Main
Page
What
is Low Vision?
What
is a Low Vision Evaluation?
What
is a Low Vision Refraction?
Why
is a Low Vision Evaluation necessary after you have seen the "worlds best"
doctors?
About
Dr. O'Connell
Low
Vision Services at the S.U.N.Y. College of Optometry
S.U.N.Y.
Faculty
Low Vision Services at
Lighthouse
International
Lighthouse
Low Vision Clinicians(pending)
Spectacles
Why
not buy a magnifier from a store or catalog?
Hand
Magnifiers
Stand
Magnifiers
Telescopes
CCTV's
Computer
Technology
Lighting
Absorptive
Lenses
Vision
Training
Social
Services
Rehabilitation
Teaching
Orientation
and Mobilty
Finding
a Low Vision Doctor
What
is a Low Vision Diplomate?
Low
Vision Diplomate Directory
These pages were constructed
by :
Dr. William F. O'Connell
They are for educational
purposes only.
Dr. O'Connell is Director
of Low Vision Services for Lighthouse International in the Hudson Valley
Region, and is Chief of Low Vision services at the S.U.N.Y. State college
of Optometry. If you are looking for the name of a Low Vision Doctor
in your area, please consult the Links found in the
"Finding a Low Vision
Doctor" page.
For an appointment:
SUNY: 212-780-5040
Lighthouse / White Plains
: 914-683-7500
Contact US: e-mail oconnellod@aol.com
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