"the basics of vision impairments and functional applications”
DESCRIPTION
Terminology Tracking- the eye’s ability to move smoothly while following a moving object. *NOT reading* Fixation- the eye’s ability to select an object in the environment and focus it’s gaze on it; and, inspecting a series of stationary objects (reading). Acuity- clearly seeing, inspecting, and identifying objects. Accommodation- the eye’s ability to automatically change focus from seeing at one distance to seeing at another. Ptosis- drooping eyelid. Convergence –the eye’s ability to turn inward. People with convergence insufficiency have trouble with near tasks such as reading and frequently report eye strain and blurred vision.TRANSCRIPT
+"The Basics of Vision Impairments and Functional Applications”
Tina Mastrangelo, MCD, CCC-SLP, Senior SLP Janine E. Pacheco, PT, DPT, C/NDT,
Melissa Lorenzo, B.SBrianna Morris, SPT
HealthSouth Rehab Hospital of Largo
+Terminology Tracking- the eye’s ability to move smoothly while
following a moving object. *NOT reading* Fixation- the eye’s ability to select an object in the
environment and focus it’s gaze on it; and, inspecting a series of stationary objects (reading).
Acuity- clearly seeing, inspecting, and identifying objects. Accommodation- the eye’s ability to automatically
change focus from seeing at one distance to seeing at another.
Ptosis- drooping eyelid. Convergence –the eye’s ability to turn inward. People
with convergence insufficiency have trouble with near tasks such as reading and frequently report eye strain and blurred vision.
+ Divergence- the ability to use both eyes as a team and be able to turn the eyes out toward a far object.
Diplopia- when two images of the same object are perceived by one or both eyes.(double vision)
Fusion- the union of images from each eye into a single image.
Strabismus- a misalignment of the eyes. The eyes don’t point at the same object together.
Tropia-always present Esotropia- when one or both eyes point inward. Exotropia- When one or both eyes point outward.
Phoria- you have to break fusion Esophoria- when one or both eyes point inward Exophoria- when one or both eyes point outward
+ Nystagmus- rhythmic oscillations or tremors of the eyes which occur independently of the normal eye movement
Occlusion- to block out light. An eye can be completely or partially blocked. Occlusion is often used to promote the use of one eye or both eyes. (ex: patching, squinting)
Suppression- Stimulated by dissimilar stimuli or when non-corresponding retinal areas are stimulated by similar stimuli or the other is temporarily inhibited or suppressed to prevent confusion.
Binocular Vision- Ability of both eyes to work together to achieve proper focus, depth perception and range of vision.
Monocular Vision- Ability of one eye to focus. No depth perception (when changing surfaces).
Saccades - Rapid shifts , or little jumps, of the eyes from object to object allowing quick localization of movements in the periphery. The ability of the eye to change fixation from point to point.
+Extra Ocular Muscles
+Visual Pathway
+Visual Pathway
+Scope of practice: ST According to ASHA’s Practice Policy on Scope of
Practice in Speech-Language Pathology, it is in an SLP’s scope of practice to asses and treat:
Cognition attention memory sequencing problem solving executive functioning
Language literacy (reading, writing, spelling)
+Scope of practice: OT
AOTA resource manual: Practice Guidelines for Adults With Low Vision Use remaining vision to participate in desired occupations Support independent lives Modify home environment to facilitate safe participation in ADLs Recommend adaptive devices and assistive technology (optical and non-optical
devices)
(www.aota.org)
The AOTA recognizes that occupational therapists help address visual impairment difficulties
Activities of Daily Living Evaluate specific daily task Evaluate environment, and recommend modifications Recommend adaptive devices and assistive technology (optical and non-optical
devices)
+Scope of practice: PT
Examining individuals with impairment, functional limitation, and disability or other health-related conditions.
Tests and measures may include the following: environmental, home, and work (job/school/play) barriers gait, locomotion, and balance neuromotor development and sensory integration sensory integrity work (job/school/play), community, leisure integration or
reintegration (including instrumental activities of daily living)
Design, implement, and modify therapeutic interventions
+Fixation The eye’s ability to select an object in the environment
and focus it’s gaze on it; and inspecting a series of stationary objects (reading).
Assessment Hold stick with a round bead 16-20 inches away from face Ask them to look at the bead for five seconds Observe their ability to focus If they are unable to complete task:
Have them hold out their own thumb & stare at it for 5 seconds. Input from their own hand may increase the ability to focus
Scoring WFL: Able to stare at bead for 5 seconds with no apparent eye
movement. Impaired: Unable to stare at bead for 5 seconds and/or has
abnormal eye movement
+Fixation Treatment Activities to encourage holding gaze on a single object Start with short duration and increase accordingly Goal:
for eyes to fixate and not dart in any other direction Achieving attention to a single object
Notes: “Fixation” requires “attention” Make it fun – Staring contest … 1.2.3 GO! Use bright colors and familiar objects Reduce stimulation in environment Provide postural stability
+Saccades Definition: Rapid shifts, or little jumps, of the eyes from
object to object allowing quick localization of movements in the periphery. The ability of the eye to change fixation from point to point.
Implications: Reading
Losing their place often skipping lines rereading lines words appearing to jump around the page letter order confusion.
Poor hand-eye coordination, i.e. ball throwing and catching, self-feeding, writing
Impaired safety
+Saccades Assessment
Hold two sticks, with different colored beads on top (i.e red and green), about shoulder width apart.
Ask them to hold their head still and look at one of the colored beads (red).
While they fixate on the red bead, move the other bead (green) up or down. Then ask them to look at the other bead.
Repeat this process until you have assessed their visual pattern.
Look for accuracy, under or over shooting, nystagmus (shaky movements), extended search time, ability or inability to isolate eyes from head movements, and ability or inability to shift into all fields of gaze
+Saccades Treatment
Have them call out letters from two columns on opposite sides of the page Change the distance between the letters by increasing blank space
or adding more columns.
Trail making Yardstick Activity Focus on both small and large saccadic training Vestibular based movement activities with demands for
saccadic skills
Always watch for speed and accuracy of fixations on targets
+Column Activity37264593
58917167
Try anything alternating• i.e. words, colors, names, objects
+Trail Making Activity
25 circles distributed over a sheet of paper Explain and demonstrate task on a separate sheet of
paper Give a worksheet (Part A, then B)
Part A : circles are numbered 1-25 Direction: Draw a line to connect circles in ascending order
Part B : Circles are labeled with both 1-13 and A-L. Pt. draws lines to connect 1 to A, A to 2, 2 to B, etc.
Record time it takes them to finish worksheet. (Baseline – Treatment – Reassessment)
+Small Precise Saccadic Movements Puzzles Word puzzles Newspaper cancellation tasks Last letter cancellation
For right hemiparesis
Wall fixation
+Large Saccadic Training
Dynavision and similar training devices http://dynavisioninternational.com/
Head and eye shifts Descriptive walking Search Strategies Large Table Cards Wii Tennis
+Visual FieldsThe part of space where objects can be seen in the peripheral even though the person is fixating their gaze on one single object ahead of them.
Broken in nasal (medial) and temporal (lateral) hemi fields Temporal (lateral) hemi field is much larger
+Central Field Also called peripheral field Highly detailed area of
the retina 5° around fixation point Responsible for
Detailed vision Reading Recognizing faces Detecting colors Highly sensitive to light Low sensitivity to motion
+Peripheral Field
The total area around central vision Becomes a secondary visual process to central vision. This process is then used as general spatial orientation
system and is integrated into the sensory-motor feedback loop
Characterized by: High sensitivity to movement Low sensitivity to light and detail
+Visual Field WNL:
50°-60° upward 70°-75° downward 60° nasally/medial 90°-110° temporally/laterally
+Field Loss vs. Visual Neglect
Physical loss of visual field to one side
Decreased Perceptual field Also Called:
Homonymous hemianopsia
Attention impairment where pt. is unable to attend to one side of their bodyAlso Called
Hemi-spatial neglect Hemiagnosia Hemi-neglect Unilateral neglect Hemi-inattention Unilateral visual
inattention Neglect syndrome
Visual Field Loss Visual Neglect
Pt. with both have a worse prognosis for recovery, due
to difficulty learning to compensate
+How Lesions Effect the Visual Field
Level 1 lesion- Can lose sight fully in one eyeLevel 2-4 lesions – Cortical blindness
Treatment: Compensate- NOT regain function
+Visual Field Loss Treatment Determine available range Use of target localization tasks to train them to make
large eye movements and systematic scanning strategies
Incorporate efficient ROM/head turning training with PT and OT treatment
Use of visual/auditory anchors Colored electric tape on table edges, doorways (red for left,
green for right) Placing objects that provide auditory feedback on the
affected side (alarm clock, phone) Appropriate challenge only (Safety first)
Compensate first to reduce stress Grade activities up as skill increases
+Visual Field Loss or Cut Assessment
Have pt. cover one eye and fixate on an object in front of them Stand behind them with a long wand Ask them to tell you when they see something in their field of
view and slowly bring the wand into their view from behind them at various angles, including: top, bottom, horizontal, diagonal approach to test each quadrant.
Present target multiple times to confirm deficit. Be cautious not to let them see your arm move because they
may guestimate when they will see the wand based on your body movement
Repeat with other eye and both eyes together
Scoring WFL: They see wand within appropriate degree measures Impairment: They don’t see the wand in their peripheral field
within the specified degrees.
+Importance of assessing patients with neurological involvement for visual neglectVisual-spatial neglect has been
reported in: up to 82% in right hemisphere strokes and 65% of left hemisphere strokes.
Yet, by using the cross-out task only as an assessment tool, neglect was found in:
only 25% of right hemisphere strokes and 2% of left hemisphere strokes.
+Neglect
Most severe •Personal – their own body
awareness
Moderately severe •Peri-personal – Their world
within arms reach
Least severe •Extra-personal – The world
beyond arms reach
+Visual Field Loss Treatment SLP’s Targets:
Communication targeting – identification of object/picture/word/paragraphs – midline, right, left
Impacts swallowing treatment ex: ability to recognize labial loss, pocketing, etc; Neck posturing
Cognition - Attention, focus, safety judgement – Fixation and Saccadic Eye Movement Training
Social interaction- pragmatics – eye contact, turn-taking
More – think in and out of the box
+Visual Field Loss TreatmentPT Examples:
Mobility trainingSafety awarenessCentral and Peripheral trainingHead and eye turns with gait retraining
Postural/Trunk midline positioningBalanceCar scanningMore – think in and out of the box
+Visual Field Loss TreatmentOT Examples:
Activities of daily living – Dressing, self-feeding, toileting
Safety awareness Body awareness in transfers, dressing Reach/Extension Independent living skills Store scanning/shopping Money Management Driving More – think in and out of the box
+Technologies:Interactive MetronomeDynaVisionVisual Restoration TreatmentPrism glasses – specialized opthomologist neuroophthomologists
+Visual Neglect TreatmentIncrease awareness of deficits
Self grading Have client grade how they think they will
perform How long will it take? What percentage will you get correct? Do you understand the activity? Will you need to ask more questions? What might effect your performance
Have client re-grade themselves after they’ve completed the task
+Visual Neglect Treatment Ideas Red Velcro Strip Red guides on side of page Tracking printed words from book on tape Vibrating pager - Set to vibrate on effected side every
12 seconds Place items on effected side and have patient look
for them and retrieve them. Marking each box of a grid with a X Money counting Checker Board
Have patients manipulate tokens vertically and horizontally across board
+Visual Neglect Treatment Use of stimuli known to activate the affected
side of the brain Left brain: use letters and numbers Right brain: use shapes and blocks
Environmental modifications at home
Incorporate motor movements of the affected side PT: clenching and unclenching affected hand during
gait retraining OT: Use the affected arm as a perceptual anchor for
full visual field scanning during performance of ADLs
+Vergence Eye teaming – or using both eyes together efficiently
Eye teaming is a reflex related to accommodation Accommodation- eye’s ability to automatically change focus from
seeing at one distance to seeing at another. Convergence – with accommodation Divergence – relaxation of accommodation
This reflex allows object fuse into single and clear, both at a distance and near.
Impairment of vergence leads to: Dioplia, or double vision Confusion Phorias- misalignment of eyes Strabismus – noticeable eye turns in or out Suppression- the brain ignores all or part of an image in order to
avoid dioplia Amblyopia – brain disregards most information coming from one or
both eyes
+Convergence The eye’s ability to turn inward. People with convergence
insufficiency have trouble with near tasks such as reading and frequently report eye strain and blurred vision.
Assessment Hold a colorful target approximately 16 inches away from the pt’s nose Instruct the pt to keep there eyes on the target as it moves closer to
them and to tell you when they see double. Slowly move the target towards the pt’s face. Observe the pt’s eyes to see when one of the deviates from the target,
signifying the point where the pt should see double.
Scoring WNL: deviation when target is 3-4 inches from pt’s nose WFL: deviation when target is 4-6 inches from pt’s nose Impaired: deviation when target is more than 6 inches from pt’s
nose.
+Convergence Treatment Brock String
A white string approx. 10-15 ft. long with three beads of various colors Tie one end of string to a stationary objects such as a door knob of
cabinet Have pt. hold the other end at the tip of their nose
Method 2 Bead positions
six inches, 18 inches and four feet from the loose end Push gaze to focus on first bead. Strings should cross Hold for 10 seconds Repeat on 2nd and 3rd beads Repeat entire process 5 times
Method 2 Place 1st bead at the place of double vision Place 2nd bead at the place of single vision
Have patient focus on each
Method 3 See treatment hand outs
+Convergence Tasks Jump Convergence
Give patient two different color pencils and position them approx. 5 feet in front of a blank wall.
Have pt. hold one pencil in left hand with their arm fully extended in front of the face. Hold the other pencil right hand and position midway between pt.’s nose and the other
pencil. Look at the pencil that is further away. Pt . should see the closer one in double. Look at the closer pencil. Pt. should see the further pencil in double Have patient bring both pencils closer to their face and look at each of them again. Repeat this exercise until patient is unable to avoid double vision when looking directly at
one of the pencils.
Dotted Card Draw a straight line in the across the middle a sheet of paper Draw 5 or more dots equally spaced along the line with different color inks Position the paper in front of pt’s face so that the line extends outward so they can see the
dots on the line. Have pt. look at the furthest dot for 10 seconds.
The rest of the dots should form a blurry letter A. Move to the next closest dot, while maintaining a single image of the furthest dot. Focus on
the second farthest dot for 10. Continue moving closer, looking at each dot for 10 seconds until the pt can no longer
maintain a single image of the dot they are focusing on. The blurry A shape should gradually transform into a blurry V-like shape as the pt. focus
on points that are closer to their nose.
+DivergenceAssessment
Position pt in front of your left side, where they can look over your shoulder.
Have pt. look at a pencil topper approx. 6 inches in front of them.
Next have pt look at an object behind you.Observe how the pts eyes turn in and out
between convergence and divergence. Repeat with pt positioned on right side.
+Divergence TreatmentDivergence
“Dynamic divergence”http://www.forbestvision.com/eye-exerc
ises-for-myopia-dynamic-divergence/
Divergence & convergence /fusionUse ipadhttp://www.forbestvision.com/dynamic-
fixation-trainer-fusion-in-divergenceconvergence/
+Ocular Alignment Alignment is crucial to coordination/function of both
eyes. If unaligned, pt. may experience double vision, vertigo, etc.
Assessment Sit directly in front of pt. at midline. Instruct pt. to look into
your eyes. Shine pen light between pt.’s eyes from 16-20 inches away Observe if the reflections in pt.’s eyes are in approximately
the same positions.
Scoring WFL: light reflects in the same position in each eye (typically
in the center of each pupil) Impaired: light reflects in different position in each eye
(strabismus of one or both eyes)
+Ocular Range of Motion Assessment
Hold a stick with a bead on top approximately 16-20 inches from pt’s face.
Instruct pt’s to keep their eyes on the bead everywhere it goes while keeping their head still
Move bead through the horizontal, vertical, and diagonal planes, holding 5 seconds between each movement. *slow and steady*
Observe the pt’s eye movements to see if they complete the full range or if their eyes drift instead
Repeat with each eye individually and together
Scoring WFL: Able to follow target through full range Impaired: if pt. is unable to follow bead
+Smooth Pursuits Movements that allow the image to stay in focus on the
retina while tracking a moving target. Quality of ROM
Assessed in conjunction with ROM During ROM assessment:
Observe the pt’s eye movements. Do they jerk, shake, or have erratic/ballistic movements.
Scoring WFL: Movements are smooth while tracking bead Impaired: Eyes jerk, have nystagmus (shaky movements) or
move erratically.
+Treatment for Alignment, ROM and Smooth Pursuits Medication Surgical SLP treatments
Acquired alignment impairments are different from congenital deficits. If problem is due to muscle imbalance,
begin eye exercises, such as ROM exercises If problem is due to double vision
occlude the affected eye ** Begin fusion exercises
Place an object where the pt can see it without double vision, then slowly move the object into the pt’s double vision range.
Adaptation of lifestyle
+Treatment for Alignment, ROM and Smooth Pursuits Therapist’s Role:
Visual tracking exercises Move head with eyes stable Move eyes with head stable Complete exercises with eyes closed Turn head right and scan left, and vice versa Grid searches Follow lines on ceilings and walls Track
people walking pen light
+Visual Spatial Skills
Skills used to understand directional concepts in space
Signs and Symptoms Difficulty distinguishing left and right Lack of coordination and balance Reverses letters or numbers when writing or copying Does not cross midline when doing tasks Gets lost following directions
+Visual Orientation Laterality:
Awareness of the two body sides and knowing they are different.
Directionality Awareness of up, down, ahead, behind, and any combination
there after
Consists of two orientations: Internal Self Awareness
i.e. left and right hands Projection into the external visual space
i.e. Understanding the difference between the left and right side of the room.
** If a pt’s internal self awareness is impaired, their concept of external visual space will also be impaired. **
+Visual Orientation AssessmentAsses pt’s awareness of left, right, up,
down, ahead, behind with both auditory and visual tasks.
Reading of minimal pairs with graphemes that have similar orthographic representations. i.e. ben, den, pen, qen
If visual orientation is impaired letter decoding will be impaired.
+Visual Orientation Tx Incorporate:
sequencing, auditory comprehension reading comprehension upper extremity movement with laterality Encourage crossing of midline
Examples: Catch and throw a ball with the left and right hands Look left – look right Place all the red items on your left and yellow ones on the right Go down the hall and turn right and tell me what picture is on the
left
+Bilateral IntegrationAbility to use both sides of the body separately and/or simultaneouslyi.e. typing, walking
Must have a solid visual orientation foundation
Using both hands to put on a shirt
+Visual Analysis/ Visual Discrimination Ability to identify, sort,
organize, store, and recall information from visual stimuli.
S/S Literacy Impairment Easily distracted Attention Impairment Difficulty understanding
directions/ sequencing
Includes: Figure Ground Visual Form Recognition/
Discrimination and Constancy
Visual Closure Visual Spatial Memory Visual Sequential Memory Visualization
+Figure Ground Ability to attend and search for specific visual
information or ignoring irrelevant information. i.e searching for a specific word or sentence in a paragraph,
specific tool in the tool box, or railing in a bathroom.
Treatment examples: Hidden picture puzzle Where’s Waldo puzzle Word Search Cancellation exercises
App: http://tactustherapy.com/app/vat/
+Visual Form Recognition/ Discrimination and Constancy Ability to discriminate differences in form including
size, shape, color and orientation i.e CAT= Cat = cat; (Which one is lower case?) Which is more water? The water in the glass or the water
in the bowl? Of these 2, which is larger?
Treatment examples: Tetris Recognition of word similarities with variation of
orthographic forms i.e. Horse = HORSE = horse
+Visual Closure The ability to recognize visual stimuli which
cues the pt to determine what an object or word should look like. i.e. Being able to complete a word or picture that is
partially obstructed, such as words on a road sign or pictures on a warning sign.
Treatment examples: Trail making with dots, letter, numbers, or words Choose the missing piece given F:3
+Visual Spatial Memory
Ability to recall the spatial location of an object or stimuli. The ability to be able to recall, identify, or reproduce a design or dominant feature of an object.
Example: Being able to picture a lost object; seeing a printed word and developing a mental picture to the corresponding object.
Treatment examples: Memory Card Game, Reduplication of bicolored block designs without a visual
reference
+Visual Sequential Memory
Ability to view and recall a sequence of numbers, letters, objects in the order they were presented. i.e recalling a phone number, how to spell a medication
name, or dosage instructions.
Treatment example: Electronic Simon Says
+Visualization
Ability to mentally manipulate a previously viewed stimuli. i.e. deciding if a flattened box will fit an object you want to
ship, if a walker will fit through a doorway, or if there is enough room to safely stand up between the chair and a supportive surface (table, grab bar, therapist)
Treatment examples: Tangram puzzles Pegboard Functional mobility around hospital, office, home with
prompts to check visualization accuracy
+Visual Midline Shift Syndrome
“mismatch between spatial information received through ambient visual process and kinesthetic, proprioceptive, and vestibular system”
Ambient visual process From the peripheral portion of the retina to the midbrain
(sensory-motor loop) to occipital cortex (feed-forward) Responsible for body awareness in space
Results in a tilt in the horizontal space causing balance deficits
Visual Midline
+VMSS Assessment
Patient position: sitting or standing
Therapist: Move an object horizontally in front of patient’s facial plane Ask patient to tell you when it is directly in front of their nose Move an object vertically in front of patient’s facial plane Ask patient to tell you when it is directly at eye level
Result: Perception to the left means visual midline has shifted to that direction
resulting in right neglect Perception of eye level when target is above eye level means there
was a posterior shift resulting in backward lean * Shift is typically away from neurologically affected side
+VMSS Treatment Neuro-opthamologists
Prescription of yoked prisms Changes orientation, and concept of midline
OT Performance of ADLs in sitting and standing position with
yoked prism
PT Gait retraining with yoked prism Static and dynamic balance training in sitting and standing
with yoked prism
+VMSS Treatment
Allow patient success 70%-80% of the time OT:
Parquetry blocks Copy a pattern Increase challenge by progressively increasing number of
blocks Puzzles
Discourage trial and error Hidden picture puzzle
Highlight magazines to Where’s Waldo? Complete the picture Tracing
+VMSS Treatment
PT: Visualizing direction
Have pt give the therapist directions from point A to point B
Follow the directions (even if wrong) Have the pt perform the task, then report it to therapy
Real life hidden picture Teach scanning strategies during performance of task
+Visual-Motor Integration Aka. Hand-eye coordination Coordination of visual perceptual skills with gross and fine
motor movements i.e. Written word repetition
S/S Poor organization Poor awareness of mistakes Sloppy writing Close working distance
Treatment examples: Interactive Metronome
Utilize visual stimuli / guides Rotations
+Visual-Auditory Integration
Visual-auditory integration Visual-auditory integration involves correlating visual
information with information heard. i.e. such as seeing a word and saying it aloud, or hearing a word and writing it down.
Involves auditory and visual skills in: Attention, Discrimination, Memory, Figure ground, and Closure
Signs and symptoms: Slow reading speed Requires frequent repetition of directions Poor spelling ability Difficulty learning to read phonetically Difficulty relating phonemes to print symbol.
+
Missing things on one side Hemi neglect and/or field cutHead turn to one side Hemi neglect and/or field cutHead tilt Restriction of gaze (usually
superior oblique), nystagmus or Double Vision
Closing one eye intermittently Double VisionClosing one eye all the time Oculomotor nerve (CN III)
palsySquinting in the distance Distance acuity, double vision,
divergence insufficiencyHeadache when watching TV or words getting jumbled up when completing activity close to pt
Convergence insufficiently, near acuity, decreased saccadic movement
+
Eyes asymmetrical Double vision, restriction of gaze, erratic tracking
Excessive blinking Convergence insufficiency, distance/near acuity
Difficulty identifying faces Distance acuity ***Over/under shoots when reaching for an item
Double vision
Pushing toward weaker side Visual midline shiftDizziness with tracking Erratic Oculomotor skillsUnable to track laterally past midline
Abducens nerve (CN VI) palsy, double vision
Keeping eyes closed Decreased visual attention, double vision, eye strain, contrast sensitivity issues
+Documentation for vision treatments Discipline specific goals
OT: Complete ADLs PT: Balance, Stand, Walk ST: Communicate, Read, Think
Keep the goals you are doing, but add the modality and facilitation of the vision prior to and throughout the task.
+Resources Information on hemianopsia and visual neglect
www. Hemianopsia.net
Trail Making App https://www.apptweak.com/trail-making-test/ipad/australia/
en/app-marketing-app-store-optimization-aso/report/689951658
Visual Perceptual/Ocular Motor activities https://www.pinterest.com/kirstenot/ot-visual-perception-oc
ular-motor-activities/