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Vision Impairment in Stroke: Intervention Or Not Coordinated by the Clinical Trials Research Centre, University of Liverpool

Glossary

The VISION trial uses a number of clinical terms to describe vision and visual field loss. This glossary explains them in plain language.

Blind sight
The ability to respond to certain visual stimuli within a perceptually blind area of visual field.
Homonymous hemianopia
Loss of half of the field of vision to one side in each eye. This is the condition studied in the VISION trial.
Monocular vision
Vision in one eye only.
Peripheral vision
The field of vision out to both sides.
Prism
An optical plastic membrane which displaces the images that are viewed through the prism.
Quadrantanopia
Loss of a quarter of the field of vision.
Scotoma
An isolated area of visual field loss.
Visual field
The whole of vision from straight ahead to the periphery, outwards.
Visual impairment
Vision loss resulting in a limitation of visual capability.
Visual scanning
Training that encourages an individual to systematically look to the right and to the left sides.

Related information

See how these terms apply in practice on the trial summary page, which shows what left and right homonymous hemianopia look like.