Background

Our occupations are almost entirely tied to vision. Occupational therapy practitioners play a vital role in understanding how vision impacts occupational performance. Mary Warren’s Visual Perception Hierarchy organizes visual function by building on visual components such as acuity, contrast, ocular motor control, visual fields, saccades, accommodation, convergence to visual processing, to finally, visual cognition and occupation.  

Warren’s Hierarchy (https://o.quizlet.com/NUZC5O5WmfihnhH7R4wJkA.png) from OTD 670 Vision and Visual Perceptual Skills

It is vital for an occupational therapist (OT) or an occupational therapist’s assistant (OTA) to know and understand these visual components as well as to conduct client screenings and assessments for each of them. If a client has an issue with vision, it will affect their daily function and how they complete their occupations. Conducting screenings and assessments will help the occupational therapist to understand their client’s visual needs and to know how to help them achieve their long-term goals and whatever they need to improve their quality of life.

Vision Screening and Assessment

This video explains ways to screen your client’s vision and visual processing.

Video is licensed under CC BY 4.0.

Vision Screening and Assessment Video Transcript

Vision Assessment and Intervention Tips

Acuity

• The ability to visually perceive things and make them sharp.
• Assess if an individual can see an object at arms-length or at a distance. The therapist can place out their name badge, hold up fingers, ask clients to describe objects in the room, read semi-distant objects, and/or use a Snellen chart.

Contrast

• The ability to look at the environment and see things that are subtly different colors.
• Assess if an individual can see similar colors. The OT can place two white objects on top of one another and ask the client to differentiate between the two or use a low contrast flip chart.

Ocular Motor Control

• The ability to visually track something resulting in normal ocular range of motion.
• Assess if an individual can follow an object with their eyes. The OT can use a stick and move it around in random patterns.

Visual Fields

• The ability to see both the peripheral and central space around you.
• Assess if an individual can see objects to the side of them. The OT can move a stick to the sides, top, and bottom of a client’s head to see when they can first see it.

Saccades

• The ability to play tennis with your eyes.
• Assess if an individual can shift their eyes. The OT can use two pens and ask the client to shift eyes between both, or move two pens in random places requiring the client to shift their eyes.

Accommodation

• The ability to refocus far away and to refocus close up.
• Assess if an individual can quickly adjust their gaze from near and far vision. The OT can ask the client to read your name badge and then ask the client to see a game-score on the TV.

Convergence

• The ability to converge eyes onto one point to perform binocular vision.
• Assess if an individual can focus both eyes on one point. The OT can ask a client if they have double vision. If yes, ask the client to follow your finger to their nose and see when double vision occurs. If the space is six inches or above, it is a problem.

Resources

• Vision Assessment and Treatment by Renee Leuschke, OTR/L
• Vision Rehab OT by Robert Constantine, OTR