Farsightedness (hyperopia) is a common vision condition in which one can see distant objects clearly, but objects nearby may be blurry.
The degree of farsightedness influences the focusing ability. People with severe farsightedness may see clearly only objects that are at a great distance, while people with mild farsightedness may be able to clearly see objects that are closer.
Farsightedness is usually present at birth and tends to run in families. The condition can be managed with eyeglasses or contact lenses. The other treatment option is surgery.
Symptoms
Signs of farsightedness include:
- Nearby objects that appear blurry
- The need to squint to see clearly
- Eyestrain including burning eyes and aching in or around the eyes
- General eye discomfort or headaches after prolonged performance of close tasks (reading, writing, drawing, computer work)
Causes
The eye has two parts that focus images:
- The cornea (clear front surface of the eye)
- The lens (clear structure inside the eye that changes shape to help focus on objects)
In a normally shaped eye, each of the focusing elements has a perfectly smooth curvature. A cornea and lens with a perfectly smooth curvature bend (refract) the incoming light to create a sharply focused image.
A refractive error
If the cornea or lens is not evenly and smoothly curved, the light rays are not bent (refracted) properly meaning there is a refractive error. Farsightedness is one type of refractive error. Farsightedness is a result of the cornea being curved too little or if the eye is shorter than normal. Consequently, light is focused behind the retina, resulting in a blurry appearance for close-up objects.
Other refractive errors
- Nearsightedness (myopia): cornea is curved too much or the eye is longer than normal making distant objects blurry.
- Astigmatism: cornea or lens is curved more steeply and causes blurry vision.
Complications
Complications associated with farsightedness include:
- Crossed eyes
- Reduced quality of life
- Eyestrain and headaches
- Impaired safety in terms of driving or operating mechanical equipment
Prevention
Farsightedness cannot be prevented; however the following steps may help protect the eyes and vision:
- Regular eye checkups
- Control of chronic health conditions (diabetes and high blood pressure can affect vision)
- Recognizing symptoms (sudden loss of vision in one eye, sudden hazy or blurred vision, flashes of light, black spots, halos or rainbows around lights)
- Protecting the eyes from the sun (ultraviolent radiation)
- A healthy diet
- Avoid smoking
- Wearing appropriate glasses to optimize the vision
- Using good lightning