Test 1: Legal Blindness & Common Eye Diseases Flashcards
legal blindness in USA
20/200 or worse - better eye, best corrected
or constricted VF 20 degrees or less in the better eye
legal blindness in the USA with the new rules
VA must be worse than 20/100 on all charts
on snellen it must be 20/200
on log chart must be worse than 20/100
legal blindness in the USA visual fields new rules
to count a point as seen it must be over 10 dB
must use humphrey 30-2, 24-2, threshold with 10 dB stimulus
kinetic perimetry such as humphrey SSA test kinetic
goldmann with III4e target
vector plotting for VF extend - see federal register website
determining the extend of the VF using the pseudoisopter
draw line b/w pts 10 dB or higher to make pseudoisopter
6 b/w each #
subtract scotomas
find line of longest extent of seen area vert, horizontal, or drag
must 20 degrees or less to qualify based on VF
other determinations of legal blindness
can use visual efficiency score which combines VA and VF into complex formula
see federal register website for more info
ramifications of legal blindness pros
easier to get social security and disability
qualifies patient for services through bureau of services for blind persons and other agencies
patient may self limit attempting dangerous activities
ramifications of legal blindness cons
cannot get a legal driver's license in many states harder to get a job if desire to work negative social implications may lose hope or struggle emotionally may become crutch to limit independence
AMD
dry (geographic), wet (exudative)
associated with aging
deteriorates center of vision - detail
accumulation of retinal waste products - dry
small, leaky blood vessels (wet) - swelling
AMD effect on daily life
problems with detail trouble seeing faces distortion or waviness of vision trouble reading and writing need for increased lighting light sensitivity loss of color vision loss of contrast vision hallucinations - charles benet syndrome misjudging depth
AMD rehab strategies
eccentric viewing use dark bold pens to write writing guides - typoscopes directional lighting - natural daylight vs standard incandescent contrast enhancing filters home adaptations - stairs, dial markings
AMD magnification strategies
distance or near illuminated or not hands free or handheld stronger the mag the less FOV using devices while eccentrically viewing - is it possible, is it best
AMD rehab referrals
vision rehab
support groups
counseling or social work
other considerations of AMD
UV protection
not smoking
healthy diet
driving - cognitive factors, reaction time, recent studies
stargardt’s
affects young and remains youth version of ARMD central, detailed vision problems same symptoms as ARMD school and workplace demands driving considerations - bioptic
diabetic retinopathy
weak, leaky blood vessels that nourish the retina
retinal swelling
center of vision may be affected
scattered vision loss all over field of vision - islands
DR effect on daily life
vision fluctuations overall blur light sensitivity may need more light to read poor contrast loss of color vision reduced peripheral vision
DR rehab strategies
need to understand VF eccentric viewing if helpful use dark bold pens to write writing guides directional lighting - natural daylight vs standard incandescent contrast enhancing filters home adaptations - stairs, dial markings
DR mag strategies
distance or near illuminated or not hands free or handheld the stronger the mag, less FOV problems with mag - enlarging scotoma, missing or distorted pieces of vision
rehab referrals for DR
vision rehab
occupational rehab
support groups
counseling or social work
other considerations of DR
control of diabetes
overall health
driving - cognitive factors, reaction time, control
RP
hereditary disease
affects retinal layer that captures light
peripheral vision affected first, then moves inward - tunnel vision
RP effect on daily life
poor side vision - bumping into things, safety, travel and mobility driving unsafe needs more light to see poor night vision contrast problems
rehab strategies for RP
utilize central vision
scanning techniques
prisms to expand side vision
reverse telescopes - make smaller (decreases VA), expand FOV
mobility training - white cane, guide dogs
bright light at night, contrast filters in daytime, mag vs mini
magnification strategies in RP
may need mag because poor VA in later stages but it decreases FOV
using minification increases FOV for mobility but further decreases VA
rule of thumb - minification may work for patients with 20/40 or better at distance, this is a patient preference
RP rehab referrals
O & M
support groups
counseling and social work
other considerations for RP
large chance of worsening - preventative care
driving is a big problem
safety is number 1 concern
can be legally blind based on VF
glaucoma
eye pressure high or too high for individual damage to ON VF loss loss of color vision loss of contrast light sensitivity glare problems
glaucoma effects on daily life
poor side vision bumping into things trouble telling colors - matching clothes need for extra light trouble with detail vision - late stages driving problems
glaucoma rehab strategies
utilize central vision
scanning techniques
prisms to expand side vision
reverse telescopes - makes smaller, expand FOV
mobility training - white cane, guide dogs
bright, directional light
contrast filters in daytime
magnification vs magnification - mag usually needed in late stages where central VA is decreased
rehab referrals for glaucoma
O & M
driving rehab
support groups
counseling and social work
other considerations for glaucoma
too much mag may be mad in combo with other ocular disease using drops regularly smoking peripheral vs central vision loss - which has occurred, which is worst
optic nerve disease
many diseases that can damage optic nerve some from birth, others later in life connection cord between eye and brain hypoplasia = small optic nerve atrophy = permanent damage to nerves
optic nerve disease effect on daily life
poor contrast - trouble seeing objects from background
blurry vision overall
loss of side vision - bumping into things, safety concerns
light sensitivity
glare problems
optic nerve disease rehab strategies
contrast is #1 strategy
mobility training
directional lighting
indoor/outdoor tints
minimize nystagmus (jerky eye movements) with contact lenses, prism
consider prism when helpful for VF defects
optic nerve disease magnification strategies
magnification usually quite helpful
the lighting conundrum - too much vs not enough, certain types are better than others, demonstrate illuminated magnifier options
magnify within confines of VF
optic nerve disease rehab referrals
vision rehab
orientation and mobility
driving rehab
occupational/school-related rehab
other considerations of optic nerve disease
good driving candidates
contrast #1
consider tinted contact lenses or glasses - photochromics
patients usually well adapted if condition is congenital
acquired ON disease requires more rehab/intervention
ABI/TBI/stroke
damage to brain causing vision loss blurry vision loss of side vision loss of eyes working together - double vision loss of focusing ability tired eyes
ABI/TBI/stroke effect on daily life
miss things to one side trouble reading double vision trouble keeping place visual confusion trouble moving around safely - bumping into things loss of depth
ABI/TBI/stroke rehab strategies
prisms/glasses to enhance side vision focusing therapies binocular vision therapies proper light spectrum filters to improve vision comfort
ABI/TBI/stroke magnification strategies
mag may be helpful but consider other issues VF (hemianopsia or other) visual neglect midline shift cognitive issues spatial/perceptual issues
ABI/TBI/stroke rehab referrals
vision rehab
orientation and mobility
support groups
counseling/social work
other considerations of ABI/TBI/stroke
additional physical problems comprehensive therapies needed visual neglect of one side recovery of side vision? spatial perception family and friends may not understand
ocular or oculocutaneous albinism
disease affecting pigmentation in eyes or eyes/skin/hair - cutaneous = skin
less or absent pigment in iris and retina - iris may appear pink, iris may appear normal in color, retina may look normal or lighter in color, causes photophobia
eye turns common
nystagmus common
ocular or oculocutaneous albinism effect on daily life
moderate to extreme light sensitivity
need for UV protection for eyes and skin
mild to severe vision loss - many patients legally blind, trouble seeing detail
visual field defects are possible but not common
ocular or oculocutaneous albinism rehab strategies
discuss importance of UV protection
limit amount of light entering eye - opaque or tinted contacts (may help nystagmus), tints and filters, glasses modifications - tint, photochromic, anti-reflective coating
prisms for moving eyes into gaze that minimizes nystagmus - null point
ocular or oculocutaneous albinism magnification strategies
magnification very helpful - lighted magnifiers - but not too much light need large FOV if have nystagmus handheld magnifiers stand magnifiers headbourne magnifiers electronic magnifiers
ocular or oculocutaneous albinism rehab referrals
driving rehab
occupational/school related rehab
other considerations of ocular or oculocutaneous albinism
otherwise healthy
often present as children or teens
may be great driving candidates
don’t underestimate the power of tints/filters and contact lenses
generally well adjusted to vision loss - congenital
cortical vision loss
damage to the visual cortex or other areas of the brain that involve the visual process
caused by - lack of oxygen to brain, infection, poor brain development, head injury, some syndromes
can exist with or without perfectly healthy eyes
cortical vision loss is often accompanied by
motor problems - disconnect between vision and motor, cerebral palsy spatial problems speech/auditory problems memory problems visual attention problems VF defects sensory overstimulation poor or absent reflex eye movements eye tracking problems visual neglect visual agnosia - inability to recognize common objects nystagmus eye turn
cortical vision loss effect on daily life
may have decreased mental capabilities, inability to sit up, stand control movements, write, inability to read (eye movement problems, spatial problems, visual memory, letter/word recognition, speech/language difficulties)
moderate to severe vision loss - often legally blind
blurry or blind spot in central vision making detail difficult to see
trouble with moving around safely or bumping into things
trouble focusing
trouble remembering
trouble with right/left concepts and spatial relationships
trouble naming or identifying common objects
cortical vision loss rehab strategies
cannot rehab without complete list of diagnoses
involve school, parents, nueropsychologist, OT, PT, vision rehab professionals, audiologist, speech/language pathologist, developmental optometrist, ophthalmologist/neuro-ophthalmologist
consider running vision info processing tests or referring for them
consider running or referring for mental assessments
test for midline shift and neglect
start simple and focus on your area of rehab team - consider eye movement therapies first
eye scanning/tracking
filters or tints to minimize visual noise
prism when indicated to help eye alignment, minimize nystagmus, compensate for VF loss or retrain neglect
motor rehab as it relates to vision - eye hand coordination, gross motor and visual planning, spatial estimation and body movement
cortical vision loss magnification strategies
magnification may or may not be helpful
depends on whether the problem is not being able to see the letter/word/object or not knowing what it is
may have physical or mental limitations to using magnification
stable magnifiers requiring less movement - stand vs handheld, consider headbourne if good head control
cortical vision loss rehab referrals
orientation and mobility
occupational/school related rehab
PT, OT, speech/language therapy, auditory processing therapy, vision therapy, neuro-developmental/behavioral therapy, sensory integration therapy, attention therapy
other considerations of cortical vision loss
you are part of a team that must work together
you may need to initiate referrals to others
therapies and insurance considerations
importance of close contact with school/TVI
never underestimate the potential for some recovery
never count these patients out
