vision rehabilitation techniques for tbi carl garbus, o.d., faao neuro vision rehabilitation...
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Vision Rehabilitation Techniques for Vision Rehabilitation Techniques for TBI TBI
Carl Garbus, O.D., FAAONeuro Vision Rehabilitation Institute
Valencia, CA
Learning ObjectivesLearning ObjectivesDescribe the incidence and prevalence of brain injury
Distinguish between acquired brain injury and traumatic brain injury
Identify basic brain structures and functions
Describe 2 main visual processes in the brain
Describe visual consequences of brain injury
Discuss assessments and interventions
Goals for the Presentation Goals for the Presentation Goals for the Presentation Goals for the Presentation Create awareness of what to look for in patients
who have had traumatic brain injury Stress the importance of having a neuro vision
evaluation for patients with traumatic brain injury and stroke
Know that neuro vision rehabilitation exists for patients with these conditions
Create awareness of what to look for in patients who have had traumatic brain injury
Stress the importance of having a neuro vision evaluation for patients with traumatic brain injury and stroke
Know that neuro vision rehabilitation exists for patients with these conditions
DefinitionsDefinitionsTraumatic brain injury (TBI)
• An insult to the brain, not of a degenerative or congenital nature but caused by an external physical force,
That may produce a diminished or altered state of consciousness.
Causes of TBI:
Motor vehicle accidents - whiplash
Falls
Gunshot wounds
Work place injuries
Shaken baby syndrome
Child abuse
Sports injuries
Military actions
Different ways brain can be damaged
Neck TraumaNeck TraumaNeck TraumaNeck Trauma
Whiplash: A simple whiplash can cause shearing of nerve
fibers in the brain stem This can occur from being rear ended by a car
driving moving at 15 miles an hour Disruption of fibers in the brainstem affects
oculomotor and binocular functions.
Whiplash: A simple whiplash can cause shearing of nerve
fibers in the brain stem This can occur from being rear ended by a car
driving moving at 15 miles an hour Disruption of fibers in the brainstem affects
oculomotor and binocular functions.
Basic brain structures Basic brain structures and functionsand functions
Lobes
" The eyes see only what the mind is ready to comprehend"
Henri Bergson
Brain and Brain and vision: vision: the connectionthe connection
Every lobe of the brain is involved in processing visual information.
To date, researchers have identified over 300 intracortical pathways linking 32 different cortical areas involved in vision function.
More than half of our gray matter and multiple subcortical areas are involved in processing vision.
There is more area of the brain dedicated to vision than to all the other senses combined.
The Visual BrainThe Visual Brain
Vision is a Bimodal Vision is a Bimodal SystemSystem
There are 2 main pathways that carry visual information from the eye to the brain.
Focal - the "what" system
Ambient - the "where system"
Designed to simultaneously process different types of visual information
Neither works in isolation of the other; both reinforce one another
Focal and Ambient SystemsFocal and Ambient SystemsFocal and Ambient SystemsFocal and Ambient Systems
Need to work in harmony
They are not isolated systems
A disconnect in the ambient system will cause problems with spatial orientation
Symptoms include: balance problems, bumping into things, difficulty navigating
Need to work in harmony
They are not isolated systems
A disconnect in the ambient system will cause problems with spatial orientation
Symptoms include: balance problems, bumping into things, difficulty navigating
Five Pillars of Five Pillars of FunctionFunction
Visual
Physical / Vestibular
Somatosensory
Cognition
Psychosocial
Why is vision rehabilitation so Why is vision rehabilitation so important following brain injury?important following brain injury?
Vision is our dominant sense; we are visual beings.
Vision is pervasive throughout our brain.
Vision is represented all over our body.
Vision influences and influenced by anything and everything - the way we think, say, or do.
Visual problems are among the most common consequences of TBI and or CVA but frequently not dealt within rehab model.
Visual Consequences of TBI: Visual Consequences of TBI: Post Trauma Vision Syndrome Post Trauma Vision Syndrome
(PTVS)(PTVS)A constellation of symptoms that evolves as secondary injury in TBI.
This syndrome is caused by a dysfunction of the ambient visual system and has the characteristics listed below:
Binocular coordination dysfunctions - double vision
Inability to perceive spatial relationships between objects
Difficulty fixating on object and following when it moves
Abnormal posture
Dizziness and balance problems
Poor visual memory
Visual consequences of TBI: Visual consequences of TBI: Post Trauma Vision Syndrome Post Trauma Vision Syndrome
(PTVS)(PTVS)
Poor concentration and visual attention
Difficulty with visually guided movements (bumping/tripping, knocking things over)
Light sensitivity / photophobia
Visual midline shift syndrome
Visual spatial difficulties
Sense of balance
Bump into things
Difficulty with eating
Slow reading
What are the functional implications?
Binocular Dysfunction
Difficulty judging distance or depth
Tendency to knock things over
Bump or trip over obstacles
Difficulty playing sports
What are the functional implications?
Visual information processing
Avoidance of crowded or busy places
Short memory
Forget familiar route
Slow to process
Visual Midline ShiftVisual Midline Shift
Visual Midline ShiftVisual Midline Shift
Mismatch between the perceived egocentric visual midline and the actual physical midlineCauses an expansion on one sideCauses a contraction on the opposite side
Mismatch between the perceived egocentric visual midline and the actual physical midlineCauses an expansion on one sideCauses a contraction on the opposite side
Visual Midline Shift SyndromeVisual Midline Shift SyndromeVisual Midline Shift SyndromeVisual Midline Shift SyndromeSigns and Symptoms
Floor may appear tilted
Walls and/or floor may appear to shift and move
Veering during mobility
Person leans away from the affected side
Feelings of imbalance or disorientation similar to vertigo
Signs and Symptoms
Floor may appear tilted
Walls and/or floor may appear to shift and move
Veering during mobility
Person leans away from the affected side
Feelings of imbalance or disorientation similar to vertigo
Cranial Nerve VIII – Cranial Nerve VIII – Auditory and Vestibular NerveAuditory and Vestibular Nerve
Cranial Nerve VIII – Cranial Nerve VIII – Auditory and Vestibular NerveAuditory and Vestibular Nerve
Nerve that transmits information for hearing and balance
Nerve that transmits information for hearing and balance
Vestibular FunctionVestibular FunctionVestibular FunctionVestibular FunctionThe visual system links up very closely with the vestibular system in the brainstem and midbrain
Vestibular –Ocular Reflex (VOR) is activated when there is a head movement, body movements or if the individual leans to one side
The visual system links up very closely with the vestibular system in the brainstem and midbrain
Vestibular –Ocular Reflex (VOR) is activated when there is a head movement, body movements or if the individual leans to one side
Vestibulo-Ocular ReflexVestibulo-Ocular ReflexVestibulo-Ocular ReflexVestibulo-Ocular Reflex Maintenance of fixation of the eyes with
head movements It is activated with horizontal and vertical
head movements This intricate system links the vestibular
system to the oculomotor system
Maintenance of fixation of the eyes with head movements
It is activated with horizontal and vertical head movements
This intricate system links the vestibular system to the oculomotor system
InterventionsInterventions
Patient education
Explain brain and vision relationship
Review individual's specific diagnosed eye condition in plain language
Why and how vision may be interfering or limiting daily functions.
Always include family members whenever possible
InterventionsInterventions
Strategies
Relieve visual discomfort from eye strain and fatigue often leading to headaches.
Take care of those dry eyes!
Reduce glare and light sensitivity - very important!
Take frequent breaks from visually demanding tasks - 20/20/20 rule
InterventionsInterventionsLimit use of computer and mobile devices
Recognize and avoid non visually- friendly reading materials
Use color filter overlays to reduce strobbing effect of black on white paper
Utilize adaptive tools to assist with visual stamina (magnifiers, Kindle, long cane)
Glasses need to be up to date
Lens is designed for the task
InterventionsInterventionsTherapy
Safety first! O&M training to improve viewing posture, balance, and stability, spatial awareness and relationships for interaction with environment with better accuracy. Long white cane training if field loss.
Strategies for Double Vision Techniques
Consult with an optometrist or ophthalmologist who has experience with brain injury
Provide a translucent patch (not dark opaque patch)Spot patchSector patchBinasalsActive therapy prescribed by the eye care
practitioner can improve binocular function- Eye Stretches, Tactile Control, Spatial Localization, Brock String
InterventionsPrisms: bends light towards the base, which causes
the image to move in the opposite direction---- has implications to change spatial orientation and eye alignment
Lenses: optical correction of refractive conditions helps to locate objects in space and helps with visual comfort
Filters: blocks specific light frequencies that cause visual discomfort which can improve visual performance
Strategies for Light SensitivityTurn off or avoid fluorescent lightingIncrease exposure to natural lightingWear prescription sunglasses with Polaroid lensesConsider side shieldsWrap around frames
Strategies for Light SensitivityBlue-tec lens filter (indoor)Green-blue filter for use in areas where fluorescent
lighting is unavoidableBinasal occlusionLight therapy program
Strategies for Disorientation and Dizziness
Grounding techniquesThumb and forefinger stimulationProprioceptive inputBreathing technique
Strategies for Improving Mobility
Special prescription glasses specially designed to enhance mobility
Consult with an optometrist/ophthalmologist who has experience with brain injury and vision rehabilitation Yoked prism lenses maybe useful in therapy or as a
full time prescriptionBinasals can provide grounding and reduce visual
confusion
Referral source is NORA
Yoked Prism Glasses
Special prism lenses prescribed by a rehabilitation eye doctor
Prisms bend light in a specific direction towards the base of the prism
Prisms can alter the patients visual spatial orientation and posture
Navigation can be improved over uneven or challenging surfaces
Yoked Prism Glasses
Demonstration
The Effect of Prisms for Mobility and Navigation
Strategies for Improving MobilityDuring mobility training observe posture, arm swing,
body alignment, balance, head position and turnsObserve visual balance When balance is a problem use the technique of
eyes leading the way before making turns Obstacle Course procedures
Obstacle CoursePlace 3 chairs approximately 3 feet apartThe patient is shown how to navigate around the
chairsChanging visual conditions for navigationAdding visual stimulus to the sidesAdding auditory stimulus
Demonstration
Strategies for Visual Field LossIdentify where the losses are located with visual fieldDoes it affect ambulation?Does it affect reading?---------------------------------------------------------------Trial Peli Prisms for hemianopsiaTrial yoked prismsImprove scanning skillsNeed single vision Rx glasses (distance and near)Progressives limit peripheral visual field function
Strategies to Enhance Visual and Vestibular Integration
Specific ProceduresHead Rotations With Central FixationChair RotationsBody RotationsFour Corner HART ChartsSide To Side HART Chart RotationsGOALS: better coordination of these systems can
be accomplished by using vision to support vestibular
SummaryConsult with an vision rehabilitation
doctor to collaborate about functional treatments
Consider visual conditions that can be treated such as light sensitivity, visual balance, visual midline shift and post trauma vision syndrome
Brainstem damage will have visual and vestibular consequences
Double vision is common problem that needs to be dealt with early
SummaryGood referral source is the Neuro
Optometric Rehabilitation Association
Avoid crowded environmentsInquire about yoked prisms and
binasal occlusion Use the grounding techniques
described in this courseDon’t give up there are many
solutions to improve the quality of life after a traumatic brain injury
Neuro Optometric Rehabilitation Conference
24th Annual Multi-disciplinary ConferenceRenaissance HotelMay 14-17, 2015Denver, COWebsite www.nora.cc
Email: [email protected]