About Visual Field Loss

What is visual field loss?

The visual field is the entire space that a person can see around them without moving their eyes. If areas of the brain that are involved in processing vision become impaired due to injury or some other factor it can result in a partial or whole loss of the visual field. This visual field loss is not experienced as darkness but is simply not seen in the same way that we cannot see behind us without moving our head and eyes.

What is hemianopia?

Hemianopia is defined as a loss of half the usual visual field. It can occur if one side of the brain has been affected by an injury or other medical condition, due to the way visual information is represented and transmitted in the brain. Hemianopia is not always complete and some of the affected half of the visual field may have functional vision.

What is cerebral vision impairment?

The definition of cerebral vision impairment has changed over the last few decades but it can simply mean a vision impairment caused by the brain being unable to effectively process visual information. It is the commonest cause of visual impairment for children and young people in developed countries. There are some common features of cerebral vision impairment but typically people with this condition experience vision very differently. Approximately 1 in 6 children with cerebral vision impairment have hemianopia, and as many as 1 in 2 may have other forms of visual field loss such as constricted visual fields.

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