Visual Impairment is defined as having a vision problem that cannot be corrected to bring it to a level that we would consider “normal.” The most extreme case of visual impairment, of course, is blindness. When one’s eyes aren’t that severe, but are still impaired, it is referred to as Low Vision. Approximately 1.3 billion people world-wide are living with some form of visual impairment. In Canada, approximately six percent of adults are visually impaired. But what do we know about visual impairment?
What does it mean to be Legally Blind?
Legally blind does not necessarily mean total sightlessness. It means that your level of visual impairment has reached the point where you cannot safely drive a car or operate machinery, even with the use of corrective lenses. In Canada, that means having a visual acuity, using the eye chart designed by Dr. Herman Snellen, of 20/200 in your better eye, even when using corrective lenses. A second way of recognizing legal blindness is to test your field of vision. If your field of vision is 20 degrees or less in your better eye, even using corrective lenses, it would give you ‘tunnel vision,” which would also make you legally blind.
What is the difference between Legal Blindness and Low Vision?
Low vision is recognized as having uncorrectable blurred vision, blind spots or tunnel vision that has not yet reached the point where it is considered legal blindness. Even though it is not yet considered legal blindness, it may feel that way to those who have it, and it may, eventually lead to legal blindness. Low vision is often brought on simply by the process of aging, but it can be caused by a side effect of eye surgery, or by Age Related Macular Degeneration (AMD). Quite simply, low vision is an uncorrectable visual impairment.
What can cause Visual Impairment?
As already mentioned, visual impairment can be caused by AMD, by eye surgery, or by the aging process. Other causes include excessive exposure to Ultra Violet (UV) Radiation, untreated Cataracts and Glaucoma, and Diabetic Retinopathy. In children, visual impairment can be caused by untreated Amblyopia (Lazy Eye), Strabismus (Crossed Eyes) or eye infections such as Pink Eye. The simple fact is, not all visual impairment can be prevented, but some can, and others can be delayed by proper care.
What Can I Do to Prevent Visual Impairment?
The best thing you can do for your vision is to take care of it. Wear sunglasses when out in the sunlight, especially in the winter, when glare from the snow can damage your eyes. Wear eye protection when working or playing sports. Most importantly, make regular appointments with your optometrist, and if you have any reason to suspect a problem with your vision, don’t hesitate to book an appointment immediately. Don’t take chances with your vision. You’ll miss it when it’s gone.