Physical Eyestrain – Misusing Our Eyes

Our vision is controlled by three set of muscles, the iris, ciliary, and extraocular muscles. All these muscles work together to allow us to see clearly. We know that muscles need to contract and release in order to function properly. When a muscle contract and hold for too long, it causes fatigue and cramping. This prevents the muscles from accommodating and converging properly resulting in a blurry and distorted image. This is physical eyestrain.

At rest, our eyes are naturally set for bright sunlight and for distant vision. Since they are at rest in bright sunlight and for distant vision, we can understand what happens when we read in low light. Our iris contract to let in more light, our extraocular muscles contract to converge and hold the eyes steady on the words, and our ciliary muscles contract to focus. Our muscles can handle this work for a short time, but if we read for many hours, our eye muscles get sore and possibly cramp. Our muscles need to contract and release to work properly over a long period. Keeping them contracted leads to vision problems.

Prolong near work causes symptoms like dry and red eyes, headaches, and double vision. Our body in its quest to maintain balance and harmony, tries to find ways to relieve any pain or strain. We experience this all the time for example, if we play a lot of tennis, our hands and feet develop callouses at places where the skin get a lot of rubbing. The rubbing causes blisters to form at the area and then callouses. The callous protects the hands and feet so that we no longer feel pain from the rubbing. The skin changes to protect itself from pain. Similarly, the eyes also tries to protect itself from strains. Since we spend most of our time in low light and doing near work, the body’s solution is to adapt the eyes for these conditions. The ciliary muscles lock the inner eye lens, bulging it and making it easier to focus on near objects. The extraocular muscles lock to converge the eyeballs making it easier to look at near object. (Beresford 1996) Locking the muscles allow us to use our eyes in these conditions longer and with less irritation or pain. This adapting however, results in long term visual problem like myopia, presbyopia, or astigmatism.

	Myopia (Nearsightedness) is a disorder where we cannot see a distant object clearly. We can focus on near objects clearly but, when we look at a distant object, the eye focus the light in front of the retina making the image appear blurry. This problem is treated with minus lens. The prescription would have a minus in front of it: -1.75 or -2.75.
	Presbyopia (Aging Eyes Farsightedness) is a disorder where we cannot focus on a near object clearly. We can focus on distant objects clearly but, when we look at a near object, the eye focus the light pass the retina making the image appear blurry. This problem is treated with plus lens. The prescription would have a plus in front of it: +1.25 or +2.5.
	Hyperopia (Farsightedness) is a disorder where we can see far objects better than we can see near objects. It is similar to presbyopia, except that in hyperopia the eyeball is a bit shorter from the front to the back. This makes it harder to see near objects. This problem is also treated with plus lens. The prescription would have a plus in front of it: +1.25 or +2.5.
	Astigmatism is a disorder where the image we see is a bit distorted. The eyeball and cornea may be warped which causes the light to bend unevenly onto the retina and make the image appear blurry or distorted. This problem is treated by adding to the minus or plus lens, for example your prescription would have another set of numbers after it: -1.25 -.75 x 180 or -2.75 +.75 x 60.

Long term vision problems is the result of our eyes adapting to help reduce pain and irritation while doing many hours of near work. Although it has adapted, the eye muscles are not meant to stay in this locked position. We know that keeping muscles contracted will cause fatigue and cramps even if we may not be able to feel it in our eyes. These cramped muscles will cause poor blood and fluid circulation in the eyes and eventually eye diseases. It is important to stop this physical eyestrain to improve our eyesight and blood circulation.

To solve the physical eyestrain, we must relieve eye muscles that are locked. The Wynning Vision Program will use sunlight and distant vision to relieve the strain. It will take time for the muscles to adapt but it will change when use in the right condition.