DEMOS Project - Visually Impaired Students and E-Learning: Frequently Asked Questions

Resources : Visually Impairment & E-Learning FAQ

Eye Conditions

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What are the main types of eye conditions?
Blind or Partially Sighted?
What sort of functional problems will a person with a visual impairment have?

What are the main types of eye conditions?

There are many and varied diseases which affect the eye and the likelihood of occurrence of an eye condition relates to a number of factors including age of the person, inheritance of genetic diseases or as a result of systemic disease.

The most common diseases of the elderly are macular degeneration and glaucoma, whilst diabetes, optic atrophy, macular degeneration and Retinitis Pigmentosa affect people from late teens to their 60's more. Younger children tend to suffer more from congenital and hereditary diseases such as retinopathy of prematurity, optic atrophy and congenital cataracts.

Blind or Partially Sighted?

These are terms used to indicate whether a person after an ophthalmic examination is recommended on a BD8 form as eligible for Blind or Partially Sighted Registration by Social Services. It is important to note that a person may be registered blind and still have very good functional vision.

What sort of functional problems will a person with a visual impairment have?

For the lay person functional problems are of most concern i.e. what effects will this condition have for the person with a visual impairment and how will they access written materials. These effects will differ from person to person and from condition to condition. Below is a list of some common difficulties and suggestions for adapting materials to provide accessibility:

Some people will have central vision loss which will lead to a dependence on large print or speech output.
Some people may have peripheral field loss, which only allows them to see a small 'tunnel', making it necessary to scan in order to see the whole screen. For these people good layout is essential e.g. left justification and still images.
Some people may have hemianopia which means they are unable to see one half of their visual field. They may have difficulty locating line beginnings, and may miss information on one side of the screen, especially if there is an empty space.
Glare is a common problem for many people with eye disease, so most will elect to work with a dark background and light print.
Good contrast is essential.
Constant print size is important, people who have eye problems are often slow to adapt to different print sizes.
People who rely on high correction in their spectacle lens will have a very definite and often very short focal length, so may work very close to the monitor.
Many people are unable to focus on moving images.

The best recommendation is KISS - Keep It Simple Sam!

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