Course # 116 Getting on Base with Learning Based Vision Problems
Clinical Practice Guideline Getting on Base with Learning Based Vision Problems Leonard J. Press, O.D., FCOVD, FAAO SECO 2012 www.aoa.org/documents/cpg 20.pdf CARE OF THE PATIENT WITH LEARNING RELATED VISION PROBLEMS Quick Reference Guide www.aoa.org/documents/qrg 20.pdf What does it mean to have what is this? Good vision? Key Optometric Websites www.covd.org College of Optometrists in Vision Development Directory of Board certified doctors Directory of Board certified therapists Research references and white papers www.oepf.org Optometric Extension Program Foundation Literature & Products (also www.bernell.com) www.aoa.org American Optometric Association Clinical Practice Guidelines A Model of Vision Visual Efficiency/Processing/Integration Visual efficiency as the app to run the hardware of the visual system Visual processing as the app to run the software of the visual system Visual integration as the app to direct effective action in our environment
Visual Efficiency Binocular control Ranges of fusion and integration with accommodation Accommodative control Amplitude, lag, facility and integration with binocular control Ocular Motor control Fixations, Pursuits and Saccades Visual Efficiency Refractive Profile Uncompensated hyperopia is associated with academic difficulties (Rosner & Rosner JAOA 1997) Is There A Lens Rx Indicated? Accommodative Disorders Insufficiency low amplitude for age level remote working distance Infacility poor transition between near far Excess (spasm) over accommodation close working distance Accommodative Tests Amplitude (20/30 letters) minus lens to blur point push up to blur point (2D> minus lens due to linear magnification) Facility (flexibility) +/ 2.00 flippers optimum at ages 8 30 @ 5 CPM (cycles per minute) Lag (resting point) MEM (near Ret) = +0.50 x cylinder (subj) = +0.50 Accommodation Fun with Hofstetter s Formula Accommodative Amplitude = 18.5 1/3 age e.g. Age 41 18.5 (40/3) = 5D Accommodative Demand = 100/viewing distance cm Normal Adult Reading Distance @ 40 cm 2.5D demand Comfort = one half of Accom Amp in reserve (</= age 41)
Binocular Vision (Motor) Direction Ortho = aligned Eso = inward drift Exo = outward drift Hyper/Hypo/Cyclo Phoria vs. Tropia Cover test Alternating vs. unilateral Tropia misaligned constantly Binocular Vision (Sensory) Gross Sensory Fusion Worth 4 Dot Test 4 dots fusion 2 or 3 dots suppression 5 dots diplopia Look for instability Binocular Measurements Phoria Measurement dissociated von Graefe (most common) two images to alignment under unfused conditions associated fixation disparity two images to alignment under fused conditions Vergence Ranges smooth Risley prism to break/recovery in phoroptor step Prism bar facility loose prism 12^BO/3^BI @ 15 cpm Nearpoint Learning Requires Convergence NPC Nearpoint of Convergence Normal Break/Recovery = 3 /6 Penlight Red/Green Normal = 4 http://www.aoa.org/documents/plrg CI Card.pdf www.childrensvision.com/reading.htm From the CI Symptom Survey of CITT Do you see the words move, jump, swim or appear to float on the page when reading or doing close work? Do you feel like you read slowly? Do you lose your place while reading or doing close work? Do you have to re read the same line of words when reading? Do you have trouble remembering what you have read?
Academic Behaviors in Children with Convergence Insufficiency with and without Parent Reported ADHD (Rouse et al Optom Vis Sci 2009) www.ncbi.nlm.nih.gov/pmc/articles/pmc2888729/ The Academic Behavior Survey (ABS) Convergence Insufficiency & Learning CI occurs more frequently with AD(H)D Symptomatic CI results in relative inattention to near tasks Parents of children with CI express more concern about academics Symptomatic CI results in significant risk factors for reading and learning disabilities Improving CI positions a child for improved reading and learning Primary Binocular Disorders Duane White Classification Convergence insufficiency (most common) Exo greater at near/receded NPC/low AC/A Convergence excess Eso greater at near/low BI range/high AC/A Divergence insufficiency Eso greater at distance/low AC/A Divergence excess Exo greater at distance/high AC/A Supplemental Binocular Classifications Basic exophoria Exo similar dist/near; normal AC/A; low NRA Basic esophoria Eso similar dist/near; normal AC/A; low PRA Fusional vergence dysfunction Ortho or eso/exo of low amount Normal AC/A; low NRA/PRA; fails +/ flippers Stereopsis Depth Perception Local tests Stereo fly and Wirt Circles Permits monocular cues Visual discrimination Global tests Random dot stereopsis Must have bifoveal fixation Figure ground Ocular Motor Systems Fixation Ability to maintain eye on stationary target or static stimulus for 10 seconds E.g. look at near target in preparation for NPC Pursuit Ability to maintain eye on moving targets or dynamic stimuli E.g. tracking a moving ball across the midline Saccade Ability to move eye along or between stationary target or stimuli E.g. fixate one target to L of midline and other to R The Type of eye movments used when reading
Oculo Motor Testing Observational Informal or NSUCO Scoring Pursuits/Versions penlight L/R/U/D/Rotations Point system for # of rotations; min. head/body movement Oculo Motor Testing Saccades King Devick or DEM Tracking a series of numbers Scored for speed & accuracy Sideline Test for Concussion Saccades two wands on either side of midline Point System for min. over/undershoot & head/body movement [X] EYE [X] Oculo Motor Testing Visagraph or Readalyzer Infrared sensors to objectively track eye movements when reading Fixations Span of letters Regressions Visual Perception Disorders Dysfunction or lack of integration among the visual processing modules in the brain Visual perception motor free Visual spatial Visual analysis Visual motor Eye hand coordination or eye body
Visual Spatial/Visual Analysis Standardized Perceptual Testing: Test of Visual Perceptual Skills VPS 3 Key Test: Test of Visual Perceptual Skills (TVPS) Subtests Visual Discrimination Visual Memory Spatial Relations Form Constancy Sequential Memory Figure Ground Visual Closure Perceptual Test Scores Data Analysis Raw Score number of correct responses Standard Score raw score adjusted for age level Percentile Rank of Standard Score performance relative to age level >75 th = high average 50 th = average <25 th = below average Visual Motor Integration Skeffington Revisited Key Test: Beery Buktenica Developmental Test of Visual Motor Integration copying geometric forms
Anti Gravity Visual Motion Hypersensitivity Visual vestibular integrative dysfunction Linked to binocular difficulties Consider test of Standing Balance Eyes Open vs. Eyes Closed Implications for 3D and video learning Winkler and Ciuffreda, Optometry 2009 Speech Language The Dyslexia Screener (TDS) Dyseidesia (visual) Dysphonesia (phonetic) Principles of Vision Therapy Vision Therapy Considerations Efficiency before processing Monocular before binocular therapy Balance between static and dynamic activities Balance between in instrument and out ofinstrument procedures Balance between office and home therapy Periodic evaluations to monitor progress Hart Chart Saccades Saccades & Visual Crowding
www.visiontherapysolutions.net/cpt.php Computerized Perceptual Therapy http://www.eyecanlearn.com/ Primary Reference Source Press LJ. Applied Concepts in Vision Therapy http://oep.excerpo.com/index.php?action=show_details&product_id=3651 Additional References Scheiman MM, Rouse MW. Optometric Management of Learning Related Vision Problems. Lane KA. Developing Ocular Motor and Visual Perceptual Skills. Equipment Resources www.oepf.org www.bernell.com www.richmondproducts.com www.visiontherapysolutions.net www.wayneengineering.com Additional Resources www.pressvision.com www.visionhelp.com Facebook: The Vision & Learning Center NJ www.sovoto.com www.visionhelp.wordpress.com THANK YOU!