Hemianopia

Hemianopia is loss of half of the visual field in one or both eyes, usually caused by damage to the visual pathways in the brain rather than to the eyes themselves.

Common symptoms

Missing half of the field of view on the same side in each eye, bumping into objects, difficulty reading, and missing things on the affected side.

Description

Hemianopia is most often caused by a stroke, but it can also follow brain injury, tumours, or surgery. Because the visual pathways cross over in the brain, damage on one side usually affects the same half of the visual field in both eyes.

The most common pattern is homonymous hemianopia, where the right or left half of the field is lost in both eyes. People may not always realise the field is missing and may turn or bump into things on the affected side, or miss part of what they read.

There is no way to regrow the damaged pathways, but vision rehabilitation, scanning training, prism glasses, and computer-based therapies can help many people cope with everyday tasks. Working with orthoptists, eye clinics, and stroke or neuro-rehabilitation teams is key.