Some vision assessment tests are likely to help health professionals distinguish between cortical and optical or ocular causes of visual impairment, according to a study in BMJ Open. 

The research, by the College and UCL, investigated the experiences of the tests in people living with posterior cortical atrophy (PCA) to examine whether some tests are more effective at discriminating between cortical and optical or ocular causes.

A visual acuity test which contrasted full and fragmented images or letters was agreed to provide the clearest evidence of PCA, or symptoms of other cortical vision problems. 

The project supports evidence that there are vision assessments that people with dementia can engage with and complete, and importantly, that these tests can help to discriminate between cortical and ocular causes of visual impairment.