WHAT IS LOW VISION?

COMMONLY ASKED QUESTIONS

WHAT IS LOW VISION?

There are several terms used in connection with the visually challenged:

• Blind - Generally refers to those who have no functional vision. These individuals may see light, shadows, indistinct colors but use Braille to read and travel using a white cane or guide dog.

• Legally blind - Defined as one whose best eye has an acuity of 20/200 or worse and/or whose peripheral vision is less than 20 degrees. This criteria is used to determine eligibility for driver's licenses, disability requirements, and services for the visually challenged.

• Low vision - Refers to those who, even with corrective eyeglasses or contact lenses, do not have clear vision. They have what is called functional vision, but have difficulty performing certain tasks such as reading regular print, performing daily tasks under normal lighting, or navigating with ease. This term has come into use in order to differentiate from the term "blind".

• Visually impaired - Probably has the most ambiguous definition of vision loss, and can cover all of the above categories.

• Visually challenged - Preferred by OUTA Sight to refer to a person with all degrees of vision loss. This term is used in place of "visually impaired".

There are many different factors that may cause low vision, including environment, diet, genes, heredity, diseases such as diabetes, physical injury, age, and ethnic background. Eye diseases that cause vision loss include cataracts, glaucoma, macular degeneration, diabetic retinopathy, retinitis pigmentosa, and many variations of these.

IS LOW VISION PREVENTABLE?

Early detection of an eye condition that can cause vision loss is probably the most critical factor in minimizing the deteriorating effects of these diseases. Some examples:

• Glaucoma is easily treatable and will cause virtually no vision loss if diagnosed very early. Testing for glaucoma is simple and quick and easily available through your optometrist or ophthalmologist.

• Macular degeneration deterioration can often be affected by early diagnosis. Immediate visits to the eye care professional upon noticing any changes in vision can have an impact on effective treatment. If you have been diagnosed with macular degeneration, it is often recommended that you take the "grid" test every day. The grid is on the menu for your convenience.

• Diabetic Retinopathy is greatly affected by early diagnosis. If you have been diagnosed with diabetes, you should begin frequent visits to your eye care professional who will monitor your retina for any hemorrhaging. Early detection brings early treatment which will help preserve vision.

• Cataracts do not necessarily require early detection, but is treatable through surgery. Cataracts do need to be monitored to determine the optimum time for surgery, which is a simple outpatient procedure. Removal of cataracts often restores vision to normal, provided there are no other eye conditions present. The patient and eye care professional mutually decide when it is time to have the cataract removed.

These are the most common eye conditions that cause vision loss. In order to maintain normal vision as long as possible, immediate visits to your eye care professional as soon as any changes in vision occur, is essential to early, effective treatment that could greatly slow down or even eliminate vision loss.

ARE THERE DIFFERENT KINDS OF LOW VISION?

Different eye conditions have different effects on vision loss. Basically, there are three types of vision loss:

• Central Vision Loss - This is the usual functional impact of macular degeneration. This type of vision loss creates difficulty in reading and seeing people's faces because it affects the central portion of their vision (or straight ahead). But the side (or peripheral) vision is intact, which is why navigating from one place to another is not too difficult. People with central vision loss often look sideways-they have to "place" the object in their line of vision, which is their side vision.

• Peripheral Vision Loss - Usually the functional impact of retinitis pigmentosa and glaucoma. This is also known as "tunnel vision". People with peripheral vision loss can see through a very small "hole" in their central vision field, thus they can read and see people's faces. But, because of their minimized side vision, they can have difficulty following moving objects and viewing large objects in its totality. They also have more difficulty in navigating due to not being able to see movements of people around them, or to see objects above, below or to their sides.

• Over-all Blurred Vision - Cataracts would be an example of an eye condition that would cause this. These people have their central and peripheral vision but there is a haze or blurriness that cannot be corrected. These people often need large print and low-glare, high-intensity lighting.

• Floaters
• Difficulty in adjusting to light change
• Color contrast becoming less distinct

WHAT ARE LOW VISION AIDS AND DEVICES?

Low vision aids and devices fall into two major categories: Optical and non-optical.

Optical devices include:

• Magnifiers
• Telescopic glasses
• Monocular and binoculars
• Head mounted magnifiers

• Talking clocks
• Writing guides
• Bold pens
• Large print items
• Bump dots (for marking dials)
• Screen magnifiers (CCTV's)
• Scanners (reads printed materials)
• Computer software that magnifies the computer screen and/or "speaks" what's on the screen
• Magnifying cameras

There is quite an assortment of low vision devices. The trick is to find the one that works best for the visually challenged individual. There are two problems: 1. To find a single place that has every possible assistive device, and 2. To be able to test these devices (preferably at home or work) to be sure it meets the unique visual requirements.

This requires determination and persistence. If there is a task or activity that a visually challenged person really wants to do, there is probably a way to do it. You may have to visit a number of places and use several devices on trial, but the benefits will definitely pay off.

There is another factor that can discourage people with low vision. The cost of some of these "high-tech" devices can be rather steep. It may be useful to compare this to the fact that if your vision allowed you to drive a car, you would be spending $15,000 to $30,000 for a car at some point. The money spent on a low vision device that will enhance your life in a way you thought no longer possible, will be well worth it! Just be sure it does what you want it to do. Check "RESOURCES" on the menu!