Vision Rehabilitation Techniques for TBI

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Vision Rehabilitation Techniques for TBI

• Carl Garbus, O.D., FAAO
• Neuro Vision Rehabilitation Institute
• Valencia, CA

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Learning Objectives

• Describe 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

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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

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Definitions

• Traumatic 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.

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• Causes of TBI
• Motor vehicle accidents - whiplash
• Falls
• Gunshot wounds
• Work place injuries
• Shaken baby syndrome
• Child abuse
• Sports injuries
• Military actions

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• Different ways brain can be damaged

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Neck 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.

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Basic brain structures and functions

• Lobes

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• " The eyes see only what the
• mind is ready to comprehend"
• Henri Bergson

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Brain and vision the 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.

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The Visual Brain
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Vision is a Bimodal System

• 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

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Focal 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

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Five Pillars of Function

• Visual
• Physical / Vestibular
• Somatosensory
• Cognition
• Psychosocial

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Why is vision rehabilitation so 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.

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Visual Consequences of TBI Post Trauma Vision
Syndrome (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

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Visual consequences of TBI Post Trauma Vision
Syndrome (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

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• Sense of balance
• Bump into things
• Difficulty with eating
• Slow reading

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What are the functional implications? Binocular
Dysfunction
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• Difficulty judging distance or depth
• Tendency to knock things over
• Bump or trip over obstacles
• Difficulty playing sports

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What are the functional implications? Visual
information processing
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• Avoidance of crowded or busy places
• Short memory
• Forget familiar route
• Slow to process

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Visual Midline Shift

• Mismatch between the perceived egocentric
• visual midline and the actual physical midline
• Causes an expansion on one side
• Causes a contraction on the opposite side

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Visual Midline Shift Syndrome

• 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

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Cranial Nerve VIII Auditory and Vestibular
Nerve

• Nerve that transmits information for hearing and
  balance

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Vestibular Function

• 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

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Vestibulo-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

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Interventions

• 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

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Interventions

• 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

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Interventions

• Limit 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

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Interventions

• Therapy
• Safety first! OM 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.

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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 patch
• Sector patch
• Binasals
• Active therapy prescribed by the eye care
  practitioner can improve binocular function- Eye
  Stretches, Tactile Control, Spatial Localization,
  Brock String

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Interventions

• Prisms 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

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Strategies for Light Sensitivity

• Turn off or avoid fluorescent lighting
• Increase exposure to natural lighting
• Wear prescription sunglasses with Polaroid lenses
• Consider side shields
• Wrap around frames

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Strategies for Light Sensitivity

• Blue-tec lens filter (indoor)
• Green-blue filter for use in areas where
  fluorescent lighting is unavoidable
• Binasal occlusion
• Light therapy program

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Strategies for Disorientation and Dizziness

• Grounding techniques
• Thumb and forefinger stimulation
• Proprioceptive input
• Breathing technique

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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 prescription
• Binasals can provide grounding and reduce visual
  confusion
• Referral source is NORA

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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

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Yoked Prism Glasses

• Demonstration
• The Effect of Prisms for Mobility and Navigation

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Strategies for Improving Mobility

• During mobility training observe posture, arm
  swing, body alignment, balance, head position and
  turns
• Observe visual balance
• When balance is a problem use the technique of
  eyes leading the way before making turns
• Obstacle Course procedures

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Obstacle Course

• Place 3 chairs approximately 3 feet apart
• The patient is shown how to navigate around the
  chairs
• Changing visual conditions for navigation
• Adding visual stimulus to the sides
• Adding auditory stimulus
• Demonstration

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Strategies for Visual Field Loss

• Identify where the losses are located with visual
  field
• Does it affect ambulation?
• Does it affect reading?
• --------------------------------------------------
  -------------
• Trial Peli Prisms for hemianopsia
• Trial yoked prisms
• Improve scanning skills
• Need single vision Rx glasses (distance and near)
• Progressives limit peripheral visual field
  function

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Strategies to Enhance Visual and Vestibular
IntegrationSpecific Procedures

• Head Rotations With Central Fixation
• Chair Rotations
• Body Rotations
• Four Corner HART Charts
• Side To Side HART Chart Rotations
• GOALS better coordination of these systems can
  be accomplished by using vision to support
  vestibular

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Summary

• Consult 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

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Summary

• Good referral source is the Neuro Optometric
  Rehabilitation Association
• Avoid crowded environments
• Inquire about yoked prisms and binasal occlusion
• Use the grounding techniques described in this
  course
• Dont give up there are many solutions to improve
  the quality of life after a traumatic brain injury

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Neuro Optometric Rehabilitation Conference

• 24th Annual Multi-disciplinary Conference
• Renaissance Hotel
• May 14-17, 2015
• Denver, CO
• Website www.nora.cc
• Email noraoptometric_at_yahoo.com