Vision Rehabilitation Techniques for TBI Carl Garbus, O.D., FAAO Neuro Vision Rehabilitation Institute Valencia, CA

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

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

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.

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 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.

Basic brain structures and functions Lobes

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

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.

The Visual Brain

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

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

Five Pillars of Function Visual Physical / Vestibular Somatosensory Cognition Psychosocial

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.

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

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

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 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

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

Cranial Nerve VIII – Auditory and Vestibular Nerve Nerve that transmits information for hearing and balance

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

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

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

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

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

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

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

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

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

Strategies for Disorientation and Dizziness Grounding techniques Thumb and forefinger stimulation Proprioceptive input Breathing 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 prescription Binasals 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 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

Obstacle Course Demonstration 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

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

Strategies to Enhance Visual and Vestibular Integration Specific 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

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

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 Don’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 Conference Renaissance Hotel May 14-17, 2015 Denver, CO Website www.nora.cc Email: noraoptometric@yahoo.com