Home vision tests
Home vision tests measure the ability to see fine detail.
Visual acuity test - home; Amsler grid test
How the Test is Performed
There are 3 vision tests that can be done at home: Amsler grid, distance vision, and near vision testing.
AMSLER GRID TEST
This test helps detect macular degeneration. This is a disease that causes 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 right in front of you, 14 inches (35 centimeters) away from your eye. Look at the dot in the center of the grid, not at the grid pattern.
While looking at the dot, you will see the rest of the grid in your peripheral vision. All the lines, both vertical and horizontal, should appear straight and unbroken. They should meet at all the crossing points with no missing areas. If any lines appear distorted or broken, note their location on the grid using a pen or pencil.
This is the standard eye chart doctors use, which has been adapted for home use.
The chart is attached to a wall at eye level. Stand 10 feet (3 meters) away from the chart. If you wear glasses or contact lenses for distance vision, wear them for the test.
Check each eye 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 to read the letters. Record the number of the smallest line that you know you read correctly. Repeat with the other eye.
This is similar to the distance vision test above, but it is held only 14 inches (35 centimeters) away. If you wear glasses for reading, wear them for the test.
Hold the near vision test card about 14 inches (35 centimeters) from your 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 you were able to accurately read.
How to Prepare for the Test
You need a well-lit area at least 10 feet (3 meters) long for the distance vision test, and the following:
The vision chart needs to be tacked to the wall at eye level. Mark the floor with a piece of tape exactly 10 feet (3 meters) from the chart on the wall.
How the Test will Feel
The tests cause no discomfort.
Why the Test is Performed
Your vision may change gradually without you being aware of it.
Home vision tests can help detect eye and vision problems early. Home vision tests should be performed under the direction of your health care provider to detect changes that may occur between eye exams. They do not take the place of a professional eye exam.
People who are at risk of developing macular degeneration may be told by their ophthalmologist to perform the Amsler grid test more often. It is best to do this test not more often than once a week. Macular degeneration changes are gradual, and you can miss them if you test daily.
Normal results for each of the tests are as follows:
What Abnormal Results Mean
Abnormal results may mean you have a vision problem or eye disease and you should have a professional eye examination.
The tests have no risks.
If you have any of the following symptoms, get a professional eye examination:
If children have any of the following symptoms, they should also have a professional eye examination:
Feder RS, Olsen TW, Prum BE Jr, et al. Comprehensive adult medical eye evaluation preferred practice pattern guidelines. Ophthalmology. 2016;123(1):209-236. PMID: 26581558 www.ncbi.nlm.nih.gov/pubmed/26581558.
Prokopich CL, Hrynchak P, Elliott DB, Flanagan JG. Ocular health assessment. In: Elliott DB, ed. Clinical Procedures in Primary Eye Care. 4th ed. Philadelphia, PA: Elsevier Saunders; 2014:chap 7.
Review Date: 2/28/2019
Reviewed By: Franklin W. Lusby, MD, ophthalmologist, Lusby Vision Institute, La Jolla, CA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
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