Eye Care
Science indicates that we do not “see” with our eyes or our brain; rather, vision is the reception and processing of visual information by the total person. Since 65% – 80% of all information we receive is visual, it becomes clear that efficient visual skills are a critical part of learning, working and even recreation.
HOW TO TAKE BETTER CARE OF YOUR VISION
Here are some basic guidelines for reducing visual stress:
– Look up occasionally: Children and adults need to look up and away from near tasks to distant objects regularly (20:20 rule).
– Reading Angle: All reading and writing besides being done at the proper distance (see Best distance), also, for best functioning, should be sloped in front of you at a 22º angle. A tilt top for the desk can be made by screwing two door stops to the back of a piece of 13mm plywood or a drawing board.
– Lighting: Illumination on what you are doing should be three times brighter than the rest of the room. Don’t read under a single lamp in a dark room. Eliminating glare is especially important for close-up work. Mixing fluorescent and incandescent light is good.
– Best distance: Reading, writing or close-up work is best done at an eye-to-activity distance equal to the length between the middle knuckle of your hand and elbow (35 to 40cm for adults).
– Sit straight: Have chest up, shoulders back and weight over the seat so both eyes are at the eye-task and at an equal distance from what is being seen.
– Reclining posture: Sit upright while reading or watching television in bed. Avoid lying on back, side or stomach.
– Writing: Hold your pencil or pen 2.5 cm or so from the tip so you can see and guide it without tilting your head or body to the side.
– Writing position: The hand you write with determines the angle at which the paper should be held.
– Television: Do not sit any closer to the TV than 180 to 240 cm and sit upright. Have indirect lamps on in the room, but placed to eliminate glare on the screen. Watching television involves and develops very few visual skills and should be limited to a few hours or less daily, especially for children.
– Participate: Do outdoor activities that require seeing at distances. Become aware of what and where things are on all sides. When walking, keep your head up, eyes wide open and look toward, not staring at objects.
– Visual discomfort while doing close-up tasks: Appropriately prescribed nearpoint lenses can reduce discomfort while making learning, seeing and earning easier and more efficient.
Nutrition
Adding certain nutrients such as lutein and zeaxanthin, vitamin C, vitamin E, zinc and Taurine to your daily diet (either through foods or supplements) can help preserve your vision and reduce the risk of certain eye diseases.
– Lutein & Zeaxanthin
Lutein and zeaxanthin reduce the risk of chronic eye diseases, including age-related macular degeneration and cataracts and is found in green leafy vegetables, as well as other foods, such as eggs.
– Vitamin C
Vitamin C is an antioxidant that could lower the risk of developing cataracts. When taken in combination with other essential nutrients, it can slow the progression of age-related macular degeneration and visual acuity loss.
– Vitamin E
Vitamin E protects cells in the eyes from unstable molecules called free radicals, which break down healthy tissue and is found in nuts, fortified cereals and sweet potatoes.
– Essential Fatty Acids
Omega-3 fatty acids are important for proper visual development and retinal function. They maintain the integrity of the nervous system, fuel cells and boost the immune system.
– Zinc
Zinc is highly concentrated in the eye, mostly in the retina and choroid (the vascular tissue layer lying under the retina). It plays a vital role in bringing vitamin A from the liver to the retina in order to produce melanin, a protective pigment in the eyes.
– Taurine
Taurine is the most abundant amino acid in the retina, vitreous, lens, cornea, iris, and ciliary body. It plays an important role as a basic factor for maintaining cellular integrity in the retina, and throughout the CNS. Taurine is found in seafood and meat.
Exercise
According to the American Academy of Ophthalmology exercising 3 times a week can greatly reduce the risk of developing glaucoma and macular degeneration. The good news about exercise is that you don’t have to be a marathon runner to reap the benefits. Taking a brisk walk, climbing the stairs and dancing are all great ways to get a good work out that will help you and your eyes stay healthy.
Protect your eyes against the harmful blue light from digital devices
Sunlight contains 25-30% blue light, so some blue light is natural. Artificial light sources emitting blue light include compact fluorescent lamps (CFL) and LEDs. These are the bulbs which are replacing traditional light bulbs. Traditional incandescent light bulbs emit very little blue light.
LEDs are found in almost every digital device including computer monitors, tablets, readers and smartphones. Additionally, studies show we hold digital devices closer to eyes than printed materials, typically 30cm for digital devices as compared to 40cm for traditional print. This also increases blue light exposure. For younger people the blue light exposure is even higher. Young people typically have larger pupils which allow even more blue light to enter the eye. Not only that, but kids age 8-18 spend an average of 7+ hours day viewing LED screens.
Research indicates that excessive blue light exposure could cause macular degeneration and disrupt sleeping patterns.
Factors that recommend blue light filters within a patient’s eyewear:
- A patient that has a strong family history of macular degeneration (AMD)
- Anyone who spends most of their day on a computer or digital device
- Patients who have had cataract surgery, as the natural blue light blocking crystalline lens has been removed.
Regular eye examinations
Regular eye examinations are essential to detect any early signs of eye diseases such as glaucoma or visual strain that could lead to myopia development. We recommend annual visits to your behavioural optometrist.
UNDERSTANDING OPTOMETRIC LANGUAGE
- Myopia
Also known as short-sightedness. This is when you struggle to see things far away. The eye is not able to compensate for it and glasses is needed to correct for the short-sightedness.
- Hyperopia
Also known as far-sightedness. This is when you struggle to see things close by. This can sometimes be confusing because if you have a high level of far-sightedness, seeing things far away can also be difficult. This is due to the lens in the eye that needs to work very hard to see things clearly. The effort to always try and make things clear can cause a lot of strain on your vision.
- Astigmatism
Often talked about as the “rugby ball shape” eye. This is when two focus points forms at the back of the eye and it causes a “ghost-image” around an image. Often a “c” can be mistaken as an “o” or a “6/8/9/0” can look very much the same.
- Presbyopia
This is when you get the feeling that your arms are getting to short. The lens in the eye starts to lose its elasticity as we get older. This causes problems with near sight and you may need reading glasses of multifocal to assist you with near focus,
- Cataracts
The lens in the eye starts to lose its clarity. It becomes milkier and your sight will look like it is “misty or cloudy”. Tests done by your optometrist will establish whether it is time to have the lenses replaced or removed.
- Macular degeneration
The part of the eye that allows us to see detail is called the macula. Macular degeneration is often age related and can run in the family. Macular degeneration causes reduced detail vision that cannot be corrected with glasses. Often magnifiers will be prescribed to help with reading.
- Glaucoma
When the pressure in the eye is too high it causes damage to the optic nerve. The effect is that the peripheral vision shrinks and can lead to tunnel vision. Drops can be used to reduce the pressure and preserve the vision. It is often a silent disease and thus yearly eye examination is necessary to screen for early detection of glaucoma.
- Strabismus
Also known as a squint or cross-eye. It is when one eye either turns in, up, down or out. Thus the two eyes do not look together and it can lead to double vision.
- Esotropia
It is when the one eye turns in to the nose. It is often associated with hyperopia.
- Exotropia
It is when one eye turns out. This is often due to weak muscles and constant visual therapy is needed to keep the eye from turning out.
- Amblyopia
Also referred to as a “lazy eye”. It is a binocular condition that cause the one eye to take over. It then causes reduced visual acuity in the “weak” eye. The causes could be due to pathology, squint or refractive error (there is a big difference in prescription between the two eyes).