Visual Perceptual Deficits It’s More than an acuity issue

1. Visual Perceptual DeficitsIt’s More than an acuity issue Presented By: Dalita Meyer, OTR/L Avera St. Luke’s

2. The Brain: A Complex Machine • Its performance tends to degrade gracefully under partial damage • In contrast, most programs and engineered systems are brittle: if you remove some arbitrary parts, very likely the whole will cease to function • It can learn (reorganize itself) from experience • This means that partial recovery from damage is possible if healthy units can learn to take over the functions previously carried out by the damaged areas

3. The Brain: A Complex Machine • It performs massively parallel computations extremely efficiently • For example, complex visual perception occurs within less than 100 ms, that is, 10 processing steps • It supports our intelligence and self-awareness • Nobody knows yet how this occurs

12. What is TIA? • A transient ischemic attack (also called TIA or “mini stroke”) is one of the most important warning signs of future stroke • A TIA occurs when a blood clot blocks an artery that supplies blood to the brain • The symptoms of a TIA, which are temporary and may last a few minutes or a few hours, can occur alone or in combination • A TIA is a medical emergency, since it is impossible to predict if it will progress into a major stroke • If you or someone you know experiences these symptoms, get emergency help • Immediate treatment can save your life or increase your chance of a full recovery

13. Age: Over 55 years of age High levels of cholesterol in blood test Smoking High blood pressure (hypertension) Diabetes Obesity Sedentary lifestyle 

14. What is TBI? • Injury caused by trauma to the skull or brain • Caused by accidents, falls, assaults, traffic accidents • Adults obtain TBI’s more frequently than any other age group • Children experience TBI’s due to accidental falls and intentional abuse • More likely to develop Alzheimer’s and Parkinson’s later in life

16. Foundation Functions • Visual attention • Oculomotor contol - Provides perceptual stability • Visual Acuity - Provides clarity – ability to see details • Visual Field - Provides awareness of objects

17. Vision Deficits Post-Stroke • Acuity • Ocular Motor Control • Visual Field Deficit • Unilateral Spatial Neglect

18. Acuity • Ability to see detail and color

19. Assessments • Acuity Tests • Contrast Tests • Reading Acuity Tests • Task Analysis

21. Treatment for Visual Acuity • Corrective lenses • Increase contrast – bright tape, paint bright labels, ligh walls w/dark furniture, contrast light switches and electrical outlets • Solid colors for rugs, bedspreads, dishes, countertops • Decrease clutter • Bold tip pens, bold line paper • Magnifiers • Motion lights • Teach compensatory skills with other senses

22. Oculomotor Assessment • Subjective complaints – Interview • Observe head and eyes • Eye dominance • Eye movements • Task Analysis

23. Oculomotor Impairment • Controlled and stabilized eye movement

24. Convergence • Essential for near vision • Complaint fatigue with reading, writing or close work

25. Types of Eye Movements • Saccadic - Change the line of sight - Activated by attention

26. Saccadic Eye Movements • Rapid eye movements that change the line of sight

27. Saccadic Eye Movements – Remedial Approach • Patient calling out or point to letters from two columns printed on opposite sides of page • Provide vestibular movements in conjunction with demands of saccadic skills

28. Saccadic Eye Movements – Adaptive Approach • Provide anchoring during reading tasks • Control the density of the visual information being presented

29. Body Scheme Disorders and Unilateral Body Neglect • Body parts • Right/left discrimination

31. Body Scheme Disorders – Remedial Approach • Provide tactile input – patient rub arm with rough cloth while name the body part • Practice particular tasks that reinforce body parts • Bilateral activities

32. Body Scheme Disorders Adaptive Approach • Educate patient and family and train family how to assist with affected side

33. Visual Attention Deficits • Changes in visual search caused by visual inattention

34. Treatment for Visual Inattention Remedial Approach • Prisms have improved this however there needs to be more studies if there is a carry over for ADL’s • Patching • Flashing lights versus static stimuli • Verbal, auditory and tactile cueing

35. Treatment for Visual Inattention Adaptive Approach • Education for patient and family • Compensatory strategies • Educate on scanning with head and eye movements by progression - Movements leading the eye from attended to unattended space - Eye movements into the unattended space - Eye movements without the use of head movements • Place all items for functional independence within the patient’s field of vision

36. The Visual Field • Area of visual world that can be seen when looking straight ahead

39. Treatment of Visual Field Deficits – Remedial Approach • Place objects commonly used on the side of the patient effected side • Provide verbal auditory and tactile cues to encourage patient to look to the affected • Practice worksheets as a treatment for scanning

40. Treatment of Visual Field Deficits – Adaptive Approach • Place items for functional independence within the patient’s field of vision • Educate patient and family about field loss – especially related to safety • Work on compensation techniques – i.e. tape, finger

41. Four Behavioral Changes - Hemianopia • Adopt a narrow search pattern confined to midline and sound side • Person scans very slowly towards deficit side • Missing and/or “misidentifying” visual detail on the “blind” side • Reduced visual monitoring of the hand

43. Reading • The dog ran quickly to his master. • Viewer-based: ckly to his master. • Object-based: he og an ickly o is ster.

44. USN and Pattern Recognition Delicious Eight licious Fight

45. Evaluation- To Inform Treatment • Reading Task • Scan Course • Telephone Number copy

46. Best Strategy - Education • Compensation requires conscious cognitive strategy • Must believe vision cannot be trusted on deficit side • Awareness allows client to develop “intellectual over-ride”

47. Organized Scanning • Left to right, clockwise counterclockwise

48. Organized Scanning – Remedial Approach • Develop strategies with the patient on how to take in visual information in an organized manner • Complete treatment activities such as crossing out target letters, mazes, puzzles, solitare card game • Locate items in a store found on a list • Locate names, items and prices in the newspaper • Locate names, number in a phone book

49. Organized Scanning – Adaptive Approach • Anchoring or cueing the patients to where to begin the visual search – tape marker • Pacing or cueing the patient about the speed of response – for impulsive or erratic scanning • Control the density or spacing of objects • Stack clothing in a consistent order

50. Ideomotor apraxia • These patients have deficits in their ability to plan or complete motor actions that rely on semantic memory. They are able to explain how to perform an action, but unable to "imagine" or act out a movement such as "pretend to brush your teeth" or "pucker as though you bit into a sour lemon." The ability to perform an action automatically when cued, however, remains intact. This is known as automatic-voluntary dissociation. For example, they may not be able to pick up a phone when asked to do so, but can perform the action without thinking when the phone rings.