Visual Perception Screen
This project is led by Dr Kathleen Vancleef.
Many patients suffer from changes in how and what they see after stroke. This prevents them from driving and can make it difficult for them to safely cross the road or participate in social situations. Although it is straightforward for a health professional to diagnose reduced visual acuity by reading a letter chart, it’s much more challenging for them to detect visual perception deficits such as recognising objects or faces, or a patient seeing motion.
The available screening tools for visual perception problems are time-consuming. Therefore, clinicians most often have to rely on what patients report and on their own observations. Unfortunately, many problems are missed that way. With this research project, we want to improve diagnosis of visual perception difficulties after stroke.
As a first step, we have interviewed occupational therapists and orthoptists (or eye movement specialists) about how they screen for visual perceptual difficulties and what their clinical needs are. They told us that they want a screening test that is quick and does not require much training. In a national survey, we asked their colleagues from all over the UK if they agreed with those clinical needs. We also asked stroke survivors and healthy older volunteers to have a look at a prototype visual perception screening test and tell us how it could be improved. They told us how to make the instructions more clear and how to make the test more user-friendly.
With this input, we have developed a novel screening tool for visual perception problems. It has tasks such as naming pictures, recognising faces, and reading text. Once the test was ready, we asked healthy volunteers to complete the screening test to determine what the normal range of scores are for people who did not have a brain injury. We have also compared scores of stroke survivors on our test with scores on an existing visual perception test to see if we reach the same conclusion with our quick test as with the longer existing test.
- Vancleef, K., Colwell, M. J., Hewitt, O., & Demeyere, N.. (2020). Current practice and challenges in screening for visual perception deficits after stroke: a qualitative study. Disability and rehabilitation, 1–10.=
- Colwell, M. J., Demeyere, N., Vancleef, K. (under review). Visual Perceptual Deficit Screening in Stroke Survivors: Evaluation of Current Practice in the United Kingdom and Republic of Ireland. Preprint available on PsyArXiv. doi:31234/osf.io/y6rjf.