Summary of needs and disabilities
VI - Vision Impairments
Vision impairment can range from no vision (blindness) or very low vision to an inability to see particular colours.
Vision impairment can happen at any age. Some conditions might result in vision problems for only a short time, but most vision conditions in children stay the same throughout life. Other conditions get worse over time, resulting in poorer vision or blindness as children get older.
What is low vision?
Low vision is when a child or young person can’t see all the things they should be able to see for their age. The child/young person might have low-to-no vision, blurred vision or loss of peripheral vision. Or they might not be able to see some colours – this is called colour blindness.
What is blindness?
This is when a child is considered legally blind:
- They can’t see at 6 meters what a child with typical vision can see at 60 meters
- Their field of vision is less than 20° in diameter (a person with typical vision can see 180°)
Causes of vision impairment
Babies might have vision impairment at birth. It can also happen later as a result of disease, injury or a medical condition. The vision impairment may be due to ocular difficulties (problems with the structures of the eyes) or because the visual pathways within the brain have been damaged (neurological vision impairments).
The most common causes of vision impairment are:
- neurological conditions that affect the parts of the brain that control sight (cortical vision impairment)
- genetic conditions like albinism and retinitis pigmentosa
- illnesses that happen to some very premature babies or to babies that have particular problems during birth
- conditions like paediatric glaucoma or cataracts and cancers like retinoblastoma
- infections with particular viruses during pregnancy – for example, rubella, cytomegalovirus, sexually transmitted infection, toxoplasmosis and so on
- structural problems with the eyes that limit vision – for example, microphthalmia or anophthalmia
- damage or injury to the eye, to the pathways connecting the eye to the brain, or to the visual centre of the brain
For more information on vision impairments visit the Royal National Institute of Blind People (RNIB)