Glossary

Short-sighted eye conditions

In the medical world short-sightedness is referred to as myopia. It occurs when the shape of your eye changes over time, often causing your eyeball to become longer. With short-sightedness distant objects appear blurred.

Short-sighted eyes may still see near objects clearly without any correction, depending on their distance in relation to the extent of the condition.

Long-sighted eye conditions

The medical term for long-sightedness is hyperopia.

With adults, long-sightedness will cause deterioration of your close vision due to the gradual loss of focusing ability of the eye.

Higher degrees of hyperopia may cause blurred vision and headaches, and sufferers may find that they begin to squint when trying to focus. These problems will be aggravated when trying to carry out close up tasks which require more focusing power.

Astigmatism

Astigmatism occurs when the front part of the eye, the cornea, is misshapen. It is elongated in one direction, as opposed to being a regular spherical shape. Because the cornea is an irregular shape, the eye can't focus the light passing through it sharply on to the back of the eye or retina. This causes blurred vision whatever the distance. The exact cause of astigmatism isn't proven - the eye is developed and formed in the womb before birth. There are many factors that are believed could cause astigmatism, including genetics and the physical conditions surrounding the foetus.

Presbyopia

Presbyopia is a condition in which the lens inside the eye loses some of its ability to focus. This happens to almost everybody and usually becomes noticeable in your mid forties. It affects close up vision, so tasks such as reading become difficult.

Whilst it does require a visit to an optometrist for an eye examination it doesn't mean that you have a serious problem with your eyes.

Visual Fatigue

Today, many people aged 20 to 45, with or without corrective lenses, suffer from visual fatigue. Causes of visual fatigue are stress, television, prolonged reading, computers. Today, our lifestyles and activities are evolving and we use our near vision at an increasing rate and for longer periods of time. Hence we suffer from both recurrent visual fatigue and discomfort.

In concrete terms, visual fatigue adversely affects our focusing while also hindering our eye accommodation, resulting in blurred vision and a feeling of discomfort.