Long-sightedness (Hyperopia): Origin and correction

If you notice that the letters become blurred and fuzzy when reading a book or newspaper, then this is already a clear indication of long-sightedness:

• You perceive close objects as blurred, while objects further away are clear and distinct.
• You have difficulties reading.
• You often squint your eyes to see more clearly.

The strain of trying to see can cause other symptoms as well:

• rapid visual fatigue
• blurred vision
• burning eyes
• painful eyes
• headache
• conjunctivitis

People with long-sightedness see objects clearly in the distance, but blurred up close. The opposite is true for shortsightedness: Here, those affected can clearly see things that are close, but with increasing distance, seeing sharply becomes more difficult. Then, for example, street signs, posters or people are only seen as blurred.

Basically, long-sightedness can develop at any age. The refractive error may already be congenital or develop in adulthood. There are two types of long-sightedness:

• Axial hyperopia: This is the most common type of long-sightedness and is congenital in most cases. The cause is either an eyeball that is too short or a malformation of the eyeball.
• Refractive hyperopia: This is a rare form of long-sightedness and occurs from an insufficient refractive power of the cornea and/or lens.

In addition, there are also special types of long-sightedness:

• Aphakia: This belongs to the group of refractive hyperopia. Aphakia is a congenital or acquired absence of the lens. Refraction of the light then only takes place through the cornea. An aphakic eye can also no longer accommodate, i.e. focus at different distances, and therefore requires a visual aid for both distant and near vision.
• Presbyopia: This is a natural ageing process of the lens of the eye. Around the age of 40 to 50, the lens loses its elasticity and thus its ability to focus at different distances (accommodation). As a result, close objects become increasingly blurred in old age, and reading also becomes more and more difficult – the arms become "too short".

Children or young people often do not even notice mild long-sightedness, as they can compensate for this visual impairment with the still strong elasticity of the eye lens and thus high accommodation capacity. Their near vision is therefore still good. This process can be selectively trained in children. However, constantly compensating for the visual impairment when doing close work or reading is tiring and can quickly lead to headaches and burning, tired eyes.

However, long-sightedness can be well compensated by a visual aid:

• Glasses: In order to produce a sharp image again, the incoming light rays are deflected by glasses with convex, i.e. outwardly curved, so-called converging, lenses and focused on the retina.
• Contact lenses: Contact lenses have the same effect as glasses, correcting visual impairment and making it easier to see in everyday life. However, they should be fitted by an eye specialist or contact lens specialist and never left in the eye for too long. Otherwise, dry eyes or other eye diseases can be the result.

A surgical intervention (refractive surgery) may also be considered. Laser treatment is now a proven method. However, this can result in complications, such as corneal scarring or an over-correction or under-correction of the longsightedness.

The unit of measurement for the refractive power is called dioptre. With long-sightedness, the dioptre value is positive. The eye specialist or optician can measure the values during an eye test and will issue a prescription for glasses accordingly. Values of, for example, + 0.25 dpt indicate a mild form of long-sightedness. But the higher the measured value (e.g. +4.0 dpt), the more pronounced the refractive error.