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Ency. home > Test > H > Home vision tests

Home vision tests   

Overview | Risks | Results

Alternative names:

Visual acuity test; Amsler grid test

Definition:

Measurement of the ability to see fine detail.

How the Test is Performed

There are 3 vision tests that can be done at home:  distance vision, near vision,  and amsler grid testing.

DISTANCE VISION:
This is the standard eye chart used by doctors adapted for use at home.  The chart is attached to a wall at eye level. Stand 10 feet away from the chart.  If you wear glasses or contact lenses for distance vision, wear them for the test. Each eye is checked separately, first the right and then the left. Keep both eyes open and cover one eye with the palm of the hand. Read the chart beginning with the top line and moving down the lines until it is too difficult read the letters. Record the number of the smallest line that was read correctly. Repeat with the other eye. Record the number of the smallest line that you were able to read accurately.

NEAR VISION:
This is similar to the distance vision test above, but for use at 14 inches. If glasses are worn for reading, wear them for the test. Hold the near vision test card about 14 inches from the eyes. Do not bring the card any closer. Read the chart using each eye separately as described above. Record the size of the smallest line which you were able to read accurately. 

AMSLER GRID TEST:
This test helps detect macular degeneration, a disease that may cause blurred vision, distortion, or blank spots.  If you normally wear glasses for reading, wear them for this test. If you wear bifocals, look through the bottom reading portion. Do the test with each eye separately, first the right and then the left. Hold the test grid directly in frontof you, 14 inches away from your eye, and look at the dot in the center of the grid. You should look only at the dot in the cnter, and not look around the grid pattern. While looking at the dot, you will see the rest of the grid in your periperal vision. All the lines, both vertical and hrizontal, should appear straight and unbroken, and meet at all the crossing points with no missing areas. If any lines appear distorted or broken you should note the location of these on the grid.

How to Prepare for the Test

A well-lit area at least 10 feet long is needed for the distance vision test. Measuring tape or yardstick, eye charts, tape or tack to hang the eye charts on the wall, pencil to record results, and if possible another person to help are needed. The vision chart needs to be tacked to the wall at eye level. Exactly 10 feet from the chart should be marked on the floor with a piece of tape.

Children:
The physical and psychological preparation you can provide for this or any test or procedure depends on your child's age, interests, previous experienceS, and level of trust. For specific information regarding how you can prepare your child, see the following topics as they correspond to your child's age:

How the Test will Feel

The test cause no discomfort.

Why the Test is Performed

Vision may change gradually, and you adjust to the change without being aware of it. Home vision tests are useful in early detection of eye and vision problems. Perform home vision tests every year.  Many people at risk for macular degeneration may be told by their ophthalmologist to perform the Amsler grid test more frequently.

Ency. home > Test > H > Home vision tests

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