Visual Perceptual Hierarchy
What are the three visual foundational skills?
Oculomotor control, visual acuity, and visual field
Even though diagnosis is not the OT scope of practice, why might it be advantageous to conduct a vision screening (other than to refer to a specialist)?
To understand which visual deficits hinder participation in areas of occupation
Your client is having difficulty drinking milk from a beige cup and coffee from a dark mug. What recommendation would you make for your client to enhance their visual performance?
Increase contrast of key components of the task and environment (For example, using a black cup for milk and white cup for coffee)
What field cut is lost for someone with binasal hemianopsia?
Vision at midline/nose, only can see from far left and right
Your client Mike has right homonymous hemianopsia. After setting up his clothing during a dressing task, you notice he only searches for and grabs clothing on the right side of the table. What causes this behavioral change?
Perceptual completion
Your client enjoys participating in painting activities. During a treatment session in the rehab gym, she decides to try to recreate the photo that is hung in her room. What visual skill is your client using?
Visual memory
When checking visual acuity and providing visual interventions, what is important to do?
Always have patient use glasses/testing with corrected vision
When performing a home evaluation, you notice that your client's living room is filled with different patterns and is very cluttered. What recommendation would you make to promote safety and enhance their visual performance in the home environment?
Reduce or eliminate background patterns and simplify the environment (for example, using solid colors on background surfaces to increase the visibility of objects)
Mirabel is unable to see using her peripheral vision, but does have vision near midline. What visual field cut does she have?
Bitemporal hemianopsia
Your client reports experiencing difficulty with reading and you notice she is unable to identify small details on a worksheet. Which behavior change is this?
Person misses and/or mis-identifies visual detail on the affected visual field
Your client, Isaac, walks around the hospital to get a “lay of the land”. What visual skill is he using?
Global visual attention
You are working on vision with your client Hernando following a TBI. What common impairment do you expect him to have?
Focus/Visual Acuity
Your client has stated that they have not been taking their medications regularly. They reported that they are having difficulty reading the labels on the medication bottle. What recommendations would you make to promote medication adherence and visual performance?
Enlarge critical features of objects and environments (for example, request the pharmacy enlarge the print on the medication labels)
During a session, you ask your client to circle every ‘A’ in a newspaper clipping. You notice that rather than scan left to right, she starts in the lower right corner and often revisits the area while searching. What diagnosis does she likely have?
Left neglect/inattention
Sally has an awareness of her visual field cut and always scans very slowly toward the deficit side during ADL re-training. You have also noticed that she sometimes has difficulty navigating the busy rehab gym. What causes this behavioral change?
Perceptual completion prevents her from seeing a distinct boundary between sighted and blind field.
Visual scanning is completed in an organized, efficient, and predictable manner. When reading we use a ___ pattern and when viewing a landscape we use a ___ pattern.
Linear, circular
Your client with Low Contrast Acuity (LCA) challenges has difficulty walking down outside steps on a cloudy day. Why is this?
LCA is the ability to see an image as it degrades in contrast from its background. This can make architecture, water, cloudy days, and faces difficult to differentiate.
Teresa is experiencing eye strain while using her iphone and mac. She stated that the background on the devices is too bright for her. What principle for enhancing visual performance would you recommend to Teresa?
Use optimal lighting principles/ provide adequate & good-quality illumination (for example, change the background from white to a darker color)
Even though perceptual completion speeds up visual processing, it also impairs what ability?
Charley has left homonymous hemianopsia and you notice he is very hesitant, stiff, and uncertain during functional mobility activities. You notice he tends to touch everything while walking to compensate. What change in mobility is he exhibiting?
Trailing
You are an OT providing a visual perceptual screening for a client after they have suffered a CVA. You ask your client to identify the differences between two letters, E & F. What visual perceptual skill are you screening for?
Pattern recognition
Why might a formal acuity screening not be appropriate for a client post-CVA/TBI?
Vision changes may continue in the months following
What are the benefits of simplifying tasks?
Addresses cognitive & visual impairments; eliminates/ modifies steps that are vision dependent
When conducting an evaluation of a visual field cut, which screening has the most consistent findings?
Kinetic 2 person with formal perimetry testing conducted by ophthalmologist/optometrist
A left-hand dominant client was recently diagnosed with left homonymous hemianopsia. Which behavioral change do you expect to occur?
Reduced visual monitoring of the hand