VFD Lecture Part 3

1. VFD Lecture Part 3

2. Damato Campimeter More precise, accurate and reliable test with better examiner control Portable Only measures central visual field

4. Test Procedure Test materials Damato Campimeter Test form Book stand (optional) Eye patch or clip on occluder (optional) Environment Well lighted room; light behind the patient and evenly illuminating the board Room must be free from distractions

5. Test Instructions Patient seated comfortably at a table with eyeglasses on if needed to see board Instruct patient to hold the board upright on the table top unless a book stand is being used EX is positioned in front of the patient so that the patient’s eyes can be observed Instruct the patient to cover the eye using the eye cover folded inward (an eye patch can be used instead) Make sure there are no shadows on the board and that the patient’s head is centered (not tilted sideways)

9. Modifications for Non Compliant Patients The number can be highlighted to help maintain the patient’s attention/fixation The number of test items can be reduced from 30 to 15 for patients with limited attention and endurance The patient can raise a finger or point to the target instead of giving a verbal response The test can be broken down into short segments and given over several days

10. Scoring

11. Additional Assessments

12. Oculomotor Changes Can be used to help confirm other observations Patient is asked to gaze shift between targets Patient often demonstrates searching saccade towards a target on the blind side Makes several saccades toward the target instead of one smooth saccade But makes a normal long smooth saccade towards the intact side

13. Insight into Visual Field Loss Patient must have good insight in order to apply compensatory strategies Patient often misunderstands diagnosis Believes the deficit is in one eye only Believes the deficit only affects peripheral field Believes the deficit is in the eye not the brain Patient is unable to describe strategies used to compensate for loss

14. Insight Can be Measured With a Simple Scale 5 Demonstrates thorough understanding of VFD; understands that deficit is in both eyes and knows which side has been affected; can describe how deficit has affected functional performance and safety; able to verbalize strategy needed to compensate and consistently employs strategy 4 Demonstrates understanding of VFD, understands that deficit is in both eyes and knows which side has been affected by deficit; can describe how deficit affects function and safety; able to verbalize strategy needed to compensate but does not consistently employ strategy

15. Insight rating … 3 demonstrates understanding of cause of VFD and which side has been affected by deficit; minimizes affect of deficit on functional performance and safety and/or does not fully understand how deficit affects function and safety; able to verbalize strategy needed to compensate but does not employ strategy 2 realizes deficit is present; knows which side is affected; may not realize deficit is in both eyes; not able to verbalize a compensatory strategy and/or cannot describe how deficit affects function and safety 1 may be aware that vision has changed but is unaware of the visual field deficit

16. Assessment of Influence of VFD on Visual Search Observational assessment Questions to be answered Does the VFD disrupt visual search? How is the search pattern disrupted? Does the patient initiate a compensatory strategy? Assess two areas Search in central visual field Search in peripheral visual field

17. Visual Search Capability in the Central Visual Field Observe performance on cancellation tasks Visual search subtests of Brain Injury Visual Assessment Battery for Adults (biVABA)

18. Normal Visual Search Persons without visual impairment demonstrate specific characteristics of search patterns that make them effective in locating and identifying targets Linear strategy Left to right and top to bottom Symmetrical search pattern Predictable search pattern Thorough and comprehensive Resilient Consistent accuracy

19. Four Normal Search Patterns

20. Characteristics of Ineffective Search Patterns Abbreviated and incomplete Asymmetrical Initiated and confined to right side Random-no predictable pattern Inconsistent accuracy in target identification Breaks down when challenged

21. Evaluating Search Effectiveness Best evaluated by observing patient complete a search task Identify strengths and weaknesses of the search pattern Note accuracy Note time needed to complete search

22. Observation of the Pattern __Symmetrical horizontal left to right __Symmetrical horizontal rectilinear __Symmetrical vertical left to right __Symmetrical vertical rectilinear __Checks work for accuracy __Abbreviated __ right side __ left side __Asymmetrical, right to left pattern __Random, no predictable pattern

23. Cuing Should be part of the evaluation Physical Verbal Helps determine strengths and weaknesses A necessary component of treatment planning Example of documentation __ verbal cue given___benefits___no benefit __ physical cue give ___benefits___no benefit

24. Ineffective Search Strategies Used by Persons with VFD Abbreviated Search Abbreviates search towards blind side due to oculomotor disruption Results in omissions on the blind side Search pattern is organized Person checks work for errors Search is often time consuming Person maintains attention throughout test

26. Visual Search Capability in the Peripheral Visual Field Search of extrapersonal environment is often affected the most To compensate for VFD, the patient must initiate a quick, efficient search of the blind side Assessment determines whether patient demonstrates the essential components of a successful compensatory search strategy

27. Dynavision 2000

30. Dynavision Performance

31. If you don’t have a Dynavision… Get one At $7,000 falls into the expensive range making it difficult to get one through standard budget procedures Look instead for a donor Hospital auxiliary Foundation supporting the hospital Sorority or service club Not that difficult as it represents a one time purchase of a unique piece of equipment that is “plaque-able” ( you can put a nice bronze donation plaque on it) Cheap man’s dynavision Laser pointer-aim it at a white wall and have patient locate the red dot

32. Scan Course Assesses integration of visual search with ambulation Observe whether patient is willing to scan the environment during ambulation or uses the maladaptive strategy of fixating on the floor or staring straight ahead Can be set up anywhere Home or clinic

34. Scan Course Performance If the patient is unable to combine visual search with ambulation, h/she will miss letter targets on the blind side The patient should always be given feedback on performance and then asked to repeat the test going the opposite direction If performance improves on second attempt it indicates that the patient is able to benefit from feedback to improve compensation

35. Supplement Evaluation with Observation of Behavior in Dynamic Environments Hesitant, uncomfortable and anxious Uses trailing or attempts to follow you Comes very close to obstacles on blind side Uncertain in responding to subtle features (curbs, support surface changes) Stopping to search-unable to combine visual search with ambulation Appears or complains of disorientation