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Home vision tests
Visual acuity test - home; Amsler grid test
Home vision tests measure the ability to see fine detail.
How the Test is Performed
There are three 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.
Macular degeneration
Macular degeneration is an eye disorder that slowly destroys sharp, central vision. This makes it difficult to see fine details and read. The diseas...
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 (36 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.
DISTANCE VISION
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 read correctly. Repeat with the other eye.
NEAR VISION
This is similar to the distance vision test above, but it is held only 14 inches (36 centimeters) away. If you wear glasses for reading, wear them for the test.
Hold the near vision test card about 14 inches (36 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:
- Measuring tape or a yardstick
- Eye charts
- Tape or tacks to hang the eye charts on the wall
- A pencil to record results
- Another person to help (if possible)
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.
Vision problems
There are many types of eye problems and vision disturbances, such as: HalosBlurred vision (the loss of sharpness of vision and the inability to see ...
People who are at risk of macular degeneration may be told by their ophthalmologist to perform the Amsler grid test more often. It is best to do this test once a week. Macular degeneration changes are gradual, and you can miss them if you test daily.
Normal Results
- Amsler grid test: All lines appear straight and unbroken with no distorted or missing areas
- Distance vision test: All letters on the 20/20 line read correctly
- Near vision test: You are able to read the line labeled 20/20 or J-1
What Abnormal Results Mean
Abnormal results may mean you have a vision problem or eye disease and you should have a professional eye examination.
-
Amsler grid test: If the grid appears distorted or broken, there may be a problem with the
retina
.
Retina
The retina is the light-sensitive layer of tissue at the back of the eyeball. Images that come through the eye's lens are focused on the retina. Th...
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Distance vision test: If you do not read the 20/20 line correctly, it may be a sign of
nearsightedness
(myopia),
farsightedness
(hyperopia),
astigmatism
, or another eye abnormality.
Nearsightedness
Nearsightedness is when light entering the eye is focused incorrectly. This makes distant objects appear blurred. Nearsightedness is a type of refr...
ImageRead Article Now Book Mark ArticleFarsightedness
Farsightedness is having a harder time seeing object that are close than things that are far away.
ImageRead Article Now Book Mark ArticleAstigmatism
Astigmatism is a type of refractive error of the eye. Refractive errors cause blurred vision. They are the most common reason why a person goes to ...
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Near vision test: Not being able to read the small type may be a sign of aging vision (
presbyopia
).
Presbyopia
Presbyopia is a condition in which the lens of the eye loses its ability to focus. This makes it hard to see objects up close.
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Risks
The tests have no risks.
Considerations
If you have any of the following symptoms, get a professional eye examination:
- Difficulty focusing on near objects
- Double vision
-
Eye pain
Eye pain
Pain in the eye may be described as a burning, throbbing, aching, or stabbing sensation in or around the eye. It may also feel like you have a forei...
Read Article Now Book Mark Article - Feeling like there is a "skin" or "film" over the eye or eyes
- Frequent changing of glasses
- Light flashes, dark spots, or ghost-like images
- Objects or faces looking blurred or foggy
- Rainbow-colored rings around lights
- Straight lines look wavy
- Trouble seeing at night, trouble adjusting to darkened rooms
If children have any of the following symptoms, they should also have a professional eye examination:
-
Crossed eyes
Crossed eyes
Strabismus is a disorder in which both eyes do not line up in the same direction. Therefore, they do not look at the same object at the same time. ...
ImageRead Article Now Book Mark Article - Difficulty in school
- Excessive blinking
- Getting very close to an object (for example, the television) in order to see it
- Head tilting
- Squinting
- Watery eyes
References
American Academy of Ophthalmology Preferred Practice Patterns Committee. Preferred Practice Pattern Guidelines. Comprehensive Adult Medical Eye Evaluation -- 2010. http://one.aao.org/preferred-practice-pattern/comprehensive-adult-medical-eye-evaluation--octobe. Accessed February 26, 2015.
Colenbrander A. Measuring vision and vision loss. In: Tasman W, Jaeger EA, eds. Duane's Ophthalmology . 2013 ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2013:vol 5, chap 51.
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Visual acuity test - illustration
Visual acuity tests may be performed in many different ways. It is a quick way to detect vision problems and is frequently used in schools or for mass screening. Driver license bureaus often use a small device that can test the eyes both together and individually.
Visual acuity test
illustration
-
Visual acuity test - illustration
Visual acuity tests may be performed in many different ways. It is a quick way to detect vision problems and is frequently used in schools or for mass screening. Driver license bureaus often use a small device that can test the eyes both together and individually.
Visual acuity test
illustration
Review Date: 2/23/2015
Reviewed By: Franklin W. Lusby, MD, ophthalmologist, Lusby Vision Institute, La Jolla, CA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.
