VISION & VISION THERAPY TANYA POLONENKO, OD, FAAO

Transcription

1 VISION & VISION THERAPY TANYA POLONENKO, OD, FAAO October 25, 2014 Down Syndrome Association of Ontario Conference RESIDENCY TRAINED OPTOMETRIST IN BINOCULAR VISION, VISION THERAPY, REHABILITATION

2 What is Vision? Development Important Visual Skills How does vision difficulties affect life? Symptoms to look for Vision and Down Syndrome Treatment Glasses Correction Critical Period of Vision Development Vision Therapy VISION & VISION THERAPY Lecture Outline Case Studies

3 WHY IS VISION SO IMPORTANT? 90% of school activities are visual in nature More information is processed through the eye than all of the rest of the body at a given moment. Vision is the fastest method of processing information Over 70% of the brain has visual connections

4 STATISTICS Vision disorders are the 4 th most common disability among children in North America (American Academy Pediatrics) 2-8% of neuro-typical preschool children have impaired vision (American Academy Pediatrics) Children with developmental delays have a much higher incident of vision problems Most common vision problems are not associated with visual acuity ( 20/20 ) (College of Optometrists in Vision Development)

5 When vision is working well, it guides and leads in all that we do; when not, it interferes. - John Streff, O.D. 5

6 VISION DEVELOPMENT Vision is learned and develops through life We are born with our vision not fully developed We learn and develop visual skills from interactions with our environment, and these experiences mold their visual perception and motor

7 PERCEPTUAL DEVELOPMENT To perceive, a child must first be able to discern differences Fixation on an object: first discrimination task (peripheral vision, fovea not yet fully developed) Motor coordination and vision develop together (Asymmetric TNR matches vision and proprioception)

8 VISION LEADS MOTOR DEVELOPMENT Random movements accidently provide the beginnings of voluntary motor control. All voluntary motor movements then stem from self-awareness. This awareness of their bodies and the world around them provides the basis for a personal mental map Mental maps are imperative for the development of bilateral coordination (both sides of the body doing the same action) and the lateralization (each side doing opposite actions)

9 VISION AND MOTOR Motor actions give the child feedback to interpret and accurately judge space visually

10 Q: WHAT IS VISION? A: Vision is the ability to make a meaningful interpretation of what is seen.

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12 Even if a person passes the 20/20 test, it does not mean they do not need glasses or that they have good vision We need to gather and interpret visual information Goal: clear, single, comfortable vision VISION: MORE THAN 20/20

13 VISUAL FUNCTIONAL SKILLS: HOW INFO GETS INTO THE BRAIN These skills determine the speed, accuracy, endurance and comfort of gathering visual information Eye Focusing (Accommodation) Eye Teaming (Binocularity) Eye Tracking (Ocular Motility) Visual-Vestibular Interaction Visual Field Aiming/Aligning (Fixation)

14 Squinting & Rubbing Eyes Closes an eye Eye turn VISION PROBLEMS Signs to look for Clumsy Reduced hand-eye coordination Avoids near tasks Family History NOTE: kids think ever yone sees they way they do! NOTE: no signs in kids with anisometropic amblyopia

15 EYE FOCUSING: ACCOMMODATION Types of Accommodative Dysfunctions: Accommodative Insufficiency Accommodative Infacility Accommodative Excess Symptoms Frontal Headache/Brow Ache Intermittent or Constant blur (distance, near, or both), worse when tired Pain around the eyes during visual activities Limited ability to read or use computer for long periods

16 VERGENCE: ASSOCIATED SYMPTOMS Diplopia Constant or Intermittent Near or Far More evident in one position of gaze Eyestrain/Fatigue after 10 minutes of performing a task driving, TV, reading, computers, studying Reduced depth perception

17 Patients will close or cover an eye Squinting Falling asleep while reading Avoidance of prolonged visually demanding tasks Dizziness/nausea

18 OCULAR MOTILITY (TRACKING) There are many areas of brain needed for reading: Pursuits/Saccades: Brainstem (Pons, Midbrain) Fixation: FEF, Parietal lobe & \Prefrontal cortex (for attention)

19 WHAT IS READING? Complex task involving precise linkage between eye movements and concurrent text processing. Precise, rhythmical, automatic saccades interspersed with fixation During fixation: processing and comprehension of text, then planning next saccade Other subsystems: vestibular (head rotated), pursuits (if material is smoothly shifted)

20 ASSOCIATED SYMPTOMS Reading difficulties: Slower reading speed Loss of place/skipping lines Missing words Poor comprehension Print seems to move/swim/jumble Difficulty tracking objects Dizziness/nausea/motion sickness

21 VISUAL PERCEPTUAL SKILLS: WHAT THE BRAIN DOES WITH VISUAL INFO Visual Discrimination Visual Memory Spatial Relations Form Constancy Figure Ground Visual Closure Visual-Motor Integration Directionality/ Laterality

22 VISUAL DISCRIMINATION Ability to distinguish different types of forms (shape, colour, orientation, edge, motion cues) People often have an inability to attend to subtle variations in form affects the patient s ability to recognize common objects (ex. mistakes button for nickel) Differentiating similar words: was vs saw

23 VISUAL MEMORY & SEQUENTIAL MEMORY Visual Memory: The ability to recall a given form or object. Important for comprehension Remembering what a word looks like or recognizing the same word on another page Copying tasks Visual Sequential Memory: ability to recall sequences of words, numbers, objects etc. Spelling accuracy No letter omissions or transpositions within words No sub-vocalization during reading

24 SPATIAL RELATIONS The ability to distinguish what is dif ferent among several objects that are the same, and be able to analyze, visualize, and maneuver visual objects in space. Understanding relationships and underlying concepts. Required for processing: Problem solving in math, science location of one's seat in the classroom space between people in a line layout of a publication or letter order of letters in a word and of words in a sentence pauses in a stream of language marked by punctuation length of an hour

25 FORM CONSTANCY The ability to manipulate forms and predict the result. recognize that a shape remains the same despite changes in size, direction, orientation and distance No letter or number reversals

26 FIGURE GROUND & VISUAL CLOSURE Figure Ground: The ability to locate a form within a crowded background. Looking for a specific piece of information when reading Knowing what to write down from the board Visual Closure: The ability to visualize in the mind s eye an incomplete picture or information. Spelling Reading comprehension & fluency

27 VISUAL MOTOR INTEGRATION The ability to integrate visual information and motor proficiency by copying forms/pictures/words Hand-eye coordination

28 DIRECTIONALITY & LATERALITY Ability to know one s own left from right, and be able to identify where objects are related to each other in space Important for correct orientation of letters Knowing how to move in space How objects relate to each other

29 SIGNS AND SYMPTOMS OF VISUAL PERCEPTUAL SKILLS DIFFICULTIES Signs: Avoids near work Frequent loss of place when reading Omits, inserts, or re-reads letters/words Failure to recognize the same word in the next sentence Poor reading comprehension Letter or word reversals after 1 st grade Difficulty copying from chalkboard Poor handwriting; misaligns numbers Book held too close to eyes Symptoms: Smart in everything but school Low self-esteem Poor self image Temper flare-ups, aggressiveness Short attention span Fatigue Frustration, stress irritability

30 VISION IN INDIVIDUALS WITH DOWN SYNDROME Down syndrome has effects on the developing eye which can impact the proper development of vision. Eye disease is reported in over half of patients with Down Syndrome Ranging from less severe to vision-threatening Particular attention should be given to vision and functional skills

31 DOWN SYNDROME AND VISION: LESS SEVERE Eyelid structure Upward slanting eyelids Prominent skin folds between eye and nose Blocked tear duct, Dry eye Discharge, tearing, irritation from eye Firm massage and eye drops Small white spots on iris Harmless Called Brushfield spots

32 DOWN SYNDROME AND VISION: MODERATE High Refractive Errors Very farsighted or nearsighted, astigmatism Often needs glasses Inward Eye Turn (esotropia) Usually becomes larger and more frequent with near tasks Bifocal glasses Amblyopia Vision is poorer than 20/20 in the absence of any obvious structural anomalies or ocular disease Glasses and Vision Therapy

33 DOWN SYNDROME AND VISION: SEVERE Nystagmus Eyes quickly move back and forth Reduced vision potential Keratoconus Thinning of cornea causing reduced vision Cataract Usually congenital Must be removed to promote vision development

34 WHAT IS OPTOMETRY S ROLE? Diagnose and treat visual disturbances to enhance visual function for use in their: Overall rehab regimen Activities of daily living: impacting overall quality of life and independence Developmental Optometrists can treat patients optically (compensating or therapeutic glasses) and/or with vision rehabilitation

35 Diagnose Establish Vision Goal VISION PROBLEMS Remove Amblyopia Cause Prescribe Glasses/Contact Lens SYSTEMATIC APPROACH TO TREATMENT Vision Therapy

36 IS IT EVER TO LATE TO TREAT AMBLYOPIA? Critical Period (birth 6m) Susceptible Period (8 18 yrs) Sensitive Period (6m 8 yrs) Residual Plasticity Period (adult) Significant effect Good effect Some effect

37 Diagnose Establish Vision Goal VISION PROBLEMS Remove Amblyopia Cause Prescribe Glasses/Contact Lens SYSTEMATIC APPROACH TO TREATMENT Vision Therapy

38 VISION THERAPY is an individualized progressive program of vision exercises prescribed to help develop or improve: Fundamental visual skills and abilities Visual comfort, ease and efficiency VISION THERAPY How a child processes or interprets visual information

39 VISION DEVELOPMENT THERAPY Patching Therapy Patching 6 hrs same as full time Vision improved 4.8 lines over 4 months AMBLYOPIA INET 12 treatment games (5 min each), child chooses 6 to do each time, 5 days a week Helps with patching compliance

40 ANTI-SUPPRESSION/AWARENESS

41 OCULAR MOTILITY: REHABILITATION Basic scanning and searching exercises Concentrate on accuracy Gradually building up speed * text size is often not an issue, it s the spacing between the lines that is critical.

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43 ACCOMMODATION: TREATMENT Vision Rehabilitation Develop flexibility between eye teaming and eye focusing systems Develop equal accommodative amplitudes Develop the ability to rapidly change focus from near to far/far to near, and sustain focus for extended periods Near vision spectacle prescription (with or without Vision Rehab)

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45 VERGENCE: REHABILITATION

46 COMPENSATORY TREATMENT OPTIONS Larger font size Larger separation between lines Reduce visual clutter Typoscope, line rule guide Use of ebooks/kindle/ipad Spatial planning games Sorting games [in developing squence] Math Isolate each problem in separate box Graph paper with larger boxes Paper with raised lines

47 QUESTIONS? Tanya Polonenko, OD, FAAO Residency trained optometrist in binocular vision, vision therapy, rehabilitation Important Website: