What is Eye strain? Definition
Eye strain or eye fatigue also referred to as asthenopia in medical terms, is defined as a condition in which your eyes get tired due to the intense and constant use of them over prolonged periods of one particular activity. It can also come about over short periods if your eyes have a refractory error and you have not corrected this error with glasses.
Eye strain is often accompanied by eye pain and headache and/or dizziness, which mostly subside after resting your eyes. The headache can be severe in cases of severe strain. The most common cause of eye strain, today, is working at the computer for prolonged periods without taking any breaks. Staring at the monitor screen continuously does take its toll on the eyes and tire them.
Eye strain causes and risk factors
There are various reasons that cause eyestrain. They include activities, which require the intense use of eyes over long periods and which can tire them unless you take proper preventive measures.
- Driving your car over long distances
- Reading a book without breaks and more so at an improper angle or distance and in poor light
- Watching television
- Computer visual syndrome: Computer Vision Syndrome (CVS) affects up to 90% of office workers in the United States. Use of computer or laptops regularly and over long periods where you stare at the monitor screen continuously can cause your eyes to tire. Old CRTs make you more prone as the images on the old monitor screens go out of focus making you strain your eyes more.
- Similarly, watching videos on your iPhone or smartphones over extended periods increase risk of eye strain.
- Video games
- Refractory error, which you have not corrected
- Exposure to extreme brightness, such as fluorescent lights
We have a lens inside each eye, which contracts and expands depending on where we are focusing our eyes, whether at a close object or at an object far away. This is done in such a manner so that the light rays coming from the object converge exactly on the retina and you view the object clearly.
This contraction and expansion are brought about by certain eye muscles attached to the eye lens. They tighten or loosen and give the eye lens the required width so that the light rays from the object are directed to converge exactly on the retina to view the object clearly.
When we stay focus, for example, on the computer monitor for a long period, these eye muscles stay locked in that position of contraction or expansion for that prolonged period and hence get strained.
When this goes on repeatedly and for long periods, these eye muscles get weakened and they are unable to operate the lens as required. Looking at the computer for prolonged periods also exposes the eye to the continuous glare from the monitor and further contributes to the strain. This can also cause eye pain and headache.
Ignoring eye strain can cause you to require glasses so that the refractory error is corrected and you view objects clearly.
Symptoms and signs
Eye strain symptoms and the accompanying headache can be annoying as they interfere with your daily activities. These symptoms do not allow you to read nor write nor work on the computer.
- A headache and eye pain are the common symptoms. The headache is often mild and located at both the temples. This type of a headache is caused by strained eye muscles. You get relief after you rest your eyes.
- Eye strain causes dizziness, which goes away after resting your eyes.
Other symptoms include
- Sore eyes with burning and/or itching
- Dry or watery eyes
- Blurred vision
- Photophobia (increased sensitivity to light)
- Twitching of the eyes.
- There may be neck and/or shoulder pain if the corresponding muscles are strained due to bad posture habits
- In the case of severe strain, symptoms become more severe.
- You rarely see eye strain in children below the age of 12 years. If your child complains of it, you should take him to an ophthalmologist and get his eyes examined to rule out any other condition.
- Eye pain accompanied by a tension headache may cause the pain in the jaw, ear or the entire head.
Eye strain symptoms can get worse
- If you have eye muscle imbalance or an uncorrected vision
- Poor posture
- Improper room lightening such as too bright or low light
- Too much or too little glare from your comp[uter monitor screen
How long does eye strain last?
Eye strain without any particular cause and just due to fatigue of the eye muscles usually last for a few minutes to a few hours after you have rested your eyes.
But, strain due to a refractory error, which requires the use of glasses will not go away till your eye vision is properly corrected.
In spite of everything, if the strain still persists, you must consult an ophthalmologist.
Eye strain does not cause any serious complications or any long term effects. It does cause eye irritation and difficulty in concentration.
The tired eyes do recover and the time taken depends on the severity of the condition. At times, it may take days. However, if there is an underlying cause such as uncorrected vision, you must get it treated. Eye strain does not damage your eyes or cause any structural changes.
However, If you work at the computer, you are at an increased risk of some long-term effects. The blue-violet and ultraviolet wavelengths that electronic devices emit can cause cataracts, macular degeneration, and retinal disease.
Treatment and home remedies
There is no medical treatment for a simple eye fatigue. Home remedies work well and give quick relief.
Eye strain symptoms without any other underlying cause go away after you have relaxed and rested your eyes. If you have strained your eyes, you must avoid tiring them any further. Do not expose your eyes further to any aggravating factors such as computer monitors, reading, or writing.
Keep away from the television. Eye strain without any other underlying cause does not require any aggressive treatment. Simple to follow measures help relieve the strained eyes
The following is a good exercise for eye strain and even otherwise. During the day, [maybe 3 or 4 times] rub your palms together till they are warm and hold them against both the eyes in such a way, that the eyes rest between the two mounds of the palm just above the wrist and warmth is felt by the eyes.
Gently move your eyes clockwise a few times and then anti-clockwise. This will also exercise the eye muscles and strengthen them. You do not have to be aggressive about it – just do it gently.
Another good home remedy to cure eye strain is to do the following at night. In the morning, collect half a cup of milk and keep it aside for the night. Do not boil the milk so that it stays raw. At night, just before lying to sleep, dip two cotton balls in this milk and soak them properly.
Squeeze them so that the milk does not drip from them, but they stay moist. Make them into flat circles and place them on each eye. Let them stay in that position for the whole night.
This will help quicken eye strain relief. Do not worry if the cotton pads fall off during the night. They will fall anyway when they dry up. Repeat this procedure until your eye strain is fully recovered.
As explained above, if you work at the computer, you are at an increased risk of cataract and retinal conditions. To protect your eye health, you should use an LCD monitor over 19 inches corner-to-corner, with Full HD resolution (1920 x 1080 pixels).
If the eye strain persists, visit an ophthalmologist, who will check your eyes for any refractory error and prescribe eye drops and/or glasses if necessary.
Tips to prevent eye strain
You should adopt certain simple measures to prevent eye strain caused by computer work, or reading or video games. When reading or writing, make sure your eyes are about one and a half feet away from the book. This is the ideal and optimal distance recommended. The light should come from behind you so that the print on the book is properly lit.
Similarly, when working on the computer, see that the monitor is below eye level, and keep your eyes about one and a half to two feet away from the monitor screen. Enlarge the text whenever possible. Keep the monitor screen resolution high and adjust the brightness to your comfort level. Clean the computer screen regularly. Keep the computer room dimly lit.
Take frequent breaks while reading or working on the computer. Follow the 20:20:20 rule. Take a 20-second break every 20 minutes and look at an object, preferably a green tree at a distance of 20 feet.
Gently massage your eyes. Place your eyes into your palms and move your palms around the eyes. This will help relax the eye muscles and give relief.