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FAQs on myopia
Computer and Health
Q. What is myopia?
A. Myopia is commonly known as "short-sightedness". A person with myopia is able to see close objects clearly but objects that are further away will appear blurred.
When the normal eye looks at an object, light rays from the object enter our eye. These light rays are bent at the cornea and the eye lens before forming an image on the inner layer of the eye called the retina. This image is then transmitted by nerve signals to the brain. The brain interprets these signals so that we see the object.
If the light rays are focused directly on the retina, we see a sharp image. Myopia occurs when the light rays from distant objects are focused in front of the retina instead of on it, resulting in blurred images on the retina. This is usually because the eyeball is too long or sometimes the cornea and lens do not bend the light rays properly.
Q. What are the complications of myopia?
A. Undetected myopia before the age of 6 years old can lead to amblyopia (lazy eye) and eventually blindness in the affected eye.
Severe myopia can lead to potentially blinding conditions such as _ retinal detachment (a condition when the retina separates from the eyeball)
- macular degeneration ( a condition when the most sensitive part of the retina degenerates and the central part of the vision is affected)
- glaucoma ( a condition where there is too much fluid pressure in the eyeball)
- cataract ( a condition where the eye lens become opaque)
The more severe the degree of myopia, the higher the risks of developing these complications.
Q. What are the causes for myopia?
A. The causal factors in the development of myopia are not clearly known. Research studies have shown that both genetic and environmental factors may contribute to myopia. Recent studies have shown that an important environmental factor is near work.
Q. Who are more likely to develop myopia?
A. A child is more likely to develop myopia if he/she has one or both parents who suffer from myopia themselves and is constantly involved in near work such as reading, writing and computer work, for long duration without a break.
Q. Can myopia be cured?
A. Currently there is no approved medication for myopia treatment. Spectacles or contact lenses are used by people who have myopia to help them see distant objects clearly. Surgical methods to correct myopia are not advisable for children as their eyeballs are still growing and the myopia has not stabilised yet.
Q. Can myopia be prevented?
A. Doctors and researchers have not discovered how to completely prevent myopia. However, near work appears to be an important environmental factor in the development of myopia. Doctors and researchers believe that it is important to limit the duration of continuous near work. When doing near work, children should be encouraged to take regular vision breaks.
Q. What is near work?
A. This term is used to describe visual activities performed at close distance, say within an arm's length, or when a person looks at or needs to focus on fine details of an object. Examples of near work are reading, writing, using the computer, drawing/painting, sewing, doing craft work with small objects and playing hand-held computer games.
Q. How does one take regular vision breaks?
A. After 30 to 40 minutes of continuous near work, one should take a vision break of 3 to 5 minutes by looking at distant objects or out of a window. In an enclosed room, one can look across the room.
Q. Does myopia affect grown-ups?
A. Myopia can affect any individual at any age. However, the severity is closely related to the age of onset. That is, if an individual who has myopia at a young age, there is a greater likelihood that the myopia will be more severe as he grows older.
Q. Is it necessary for me to wear glasses if I am slightly myopic?
A. One should still wear corrective lens as they can help prevent one from squinting and overstraining the eyes for a clearer vision. With the help of glasses, light rays can fall properly on the retina to form a clearer image.
Q. Will full time wearing of glasses worsen my myopic condition?
A. There is no evidence of the effects of spectacle wear on myopia (i.e. full-time wear, part-time wear such as only when looking at a distance, or no wear). However, children younger than 8 years old who have myopia should wear spectacles at all times to prevent a lazy eye.
Q. Can wearing of under-corrected or over-corrected spectacles reduce myopia progression?
A. Some eye-care practitioners prescribe under-corrected spectacles as they believe that this will help reduce myopia progression. However, there is no research evidence that wearing of under or over-corrected spectacles reduces myopia progression.
Q. Can wearing of contact lenses help in reducing myopia progression?
A. Contact lenses have the same function as a pair of spectacles. The pair of contact lenses helps to refract the light rays to form a clearer image on the retina. Although there have been studies on the use of contact lenses in controlling myopia progression, there is currently no conclusive evidence that wearing of contact lenses can reduce myopia progression.
Q. Does the colour green have a soothing effect on the eyes?
A. There is no evidence that the colour green produces a soothing effect on the eyes or helps prevent myopia. However, to relax the eyes, one should take vision breaks of 3 to 5 minutes after every 30 to 40 minutes of near work and also to look at some distant objects to relax the eyes.
Q. Does surgical treatment work for myopia?
A. Myopia cannot be cured but laser treatment can reduce the severity of myopia. However, such treatment is not suitable for children and young teenagers in whom myopia is still progressing and has not stabilised yet.
Q. If myopia is partly hereditary, does it still help to practise good eye care habits?
A. As the current research evidence shows that an important environmental factor is near work, it is important for the children to take vision breaks to limit the duration of continuous near work and to practise good eye care habits. This may help to delay the early onset of myopia in young children.
The severity of myopia is closely related to the age of onset. That is, if an individual who has myopia at a young age, there is a greater likelihood that the myopia will be more severe as he or she grows older.
Q. Can watching television for long periods cause myopia?
A. It has not been proven yet that television watching has an effect on myopia. However, it is important to advise children to watch television from a distance of at least two to three metres.
Q. Is it important to ensure that there is adequate lighting in the room during near work activities?
A. Although the causal factors for myopia are not clearly known yet, parents and teachers should always ensure that there is adequate lighting in areas or rooms allocated for near work activities such as reading, writing and using a computer.
Avoid excessive glare from shining onto the children's books or face when reading. Ensure that they hold their books about 30 cm away from their eyes and sit upright on a comfortable chair.
When using the computer, adjust the screen to reduce glare. Glare can result from the reflections of other sources of light. The computer screen should be placed about 50cm from the eyes.
Q. Can eye exercises help to reduce myopia?
A. Presently, eye exercises have not been proven to prevent myopia. The eye exercise that was introduced in schools, originates from China and is based on acupressure points. It is believed to relieve eye strain and as an art of relaxation. There are no reported harmful effects of the eye exercises.
Q. Can myopia be prevented by participating in more outdoor activities?
A. It is not proven whether outdoor activities can prevent myopia or delay myopia progression. There is a trend of increasing prevalence of myopia among young children and researchers have noted that children spend less time on outdoor activities. Children are encouraged to participate in outdoor activities like sports as these activities usually do not involve near work.
Q. Does eating foods rich in Vitamin A help to prevent myopia?
A. Vitamin A deficiency will cause night blindness and not myopia. It is important, however, to encourage children to eat a balanced diet and lead a healthy lifestyle.
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Health & safety
Because there are so many children of varying ages and sizes in a before
and after school care program, it is essential to pay attention to health
and safety issues. Children need to be taught simple safety principles from
the time they begin using computers. Don't overlook the obvious when children
use computers. For children as well as adults, bad posture can cause sore wrists, eye fatigue, headaches, neck strain and even back pain. Since kids may be using computers both at home and at school, there is the potential for problems to develop over time.
To prevent eye problems, avoid flickering lights or glare on the screen, and look away from the monitor frequently. (This is true for video games also.) Get up and walk around (moving around rests both the eyes and the body), focus on a distant object, remember not to stare at the screen, and blink often.
Furniture that is used should be safe and adjustable so it fits each child. If you can't find sturdy, adjustable furniture, have some available that fits the different sizes of the children using it. Because many sizes and shapes of children will probably be using a computer area that has been set up for one "size" of students, careful monitoring of the physical set up should occur when each new student sits down. Make the appropriate adjustments for each child according to the guidelines listed below.
Your health - headaches and eye strain
What are headaches and eyestrain?
Headaches can be caused by many different factors and are one of the most common reasons people visit their GP. Most headaches are not serious and usually disappear on their own. They can be relieved by mild painkillers, or a positive change in lifestyle.
Eyestrain is also a common complaint among people doing 'close' work e.g. those who work using computer monitors. Eyestrain can be a trigger for headaches, but can usually be avoided by following simple guidelines.
What are the signs of headache or eyestrain?
A headache can range from a mild, throbbing feeling to a sharp, stabbing pain. Headaches can affect your whole head or just a part of it. The pain may move around, affect your vision or even cause nausea and vomiting. The two most common types of headache are tension headaches and migraine.
Tension headaches do not usually last for a long time. Common symptoms of a tension headache include
Eye discomfort in the office
What is the significance of "good" lighting? Office work is visually demanding and has always required good lighting for maximum comfort and productivity. "Good" lighting means providing enough illumination so that people can see printed, handwritten or displayed documents clearly but are not blinded by excessively high light levels (a cause of glare). The introduction of computers in the 1970's increased the visual demands of office work and made lighting design even more challenging. While typewriters were being exchanged for computers, the need for redesigning or rearranging office lighting was commonly overlooked.
What are signs of poor lighting? The most common complaints resulting from poor lighting are: eyestrain, eye irritation, blurred vision, dry burning eyes, and headaches. Poor lighting affects not only the ocular system but can also contribute to stiff necks and aches in shoulder area. These problems can occur when people adopt poor or awkward postures when trying to read something under poor lighting conditions.
Vision / eye strain
Visual problems, such as eyestrain and irritation, are among
the most frequently reported complaints by computer operators. These
visual symptoms can result from improper lighting, glare from the
screen, poor positioning of the screen itself, or copy material that is
difficult to read. These problems usually can be corrected by adjusting
the physical and environmental setting where the computer users work.
For example, work stations and lighting can and should be arranged to
avoid direct and reflected glare anywhere in the field of sight, from
the display screen, or surrounding surfaces.
You also can reduce eyestrain by taking vision breaks, which
may include exercises to relax eye muscles after each hour or so of
operating a computer. Changing focus is another way to give eye muscles
a chance to relax. You only need to glance across the room, or out the
window, from time to time and look at an object at least 20 feet away.
Other eye exercises may include rolling or blinking the eyes, or
closing them tightly for a few seconds.
