Amsler Grid Eye Test

What is the Amsler grid eye test?

The Amsler grid is a visual testing tool that makes it easier for you to see distortions in your vision from conditions that affect your retinas. It’s also sometimes known as the Amsler eye chart. This chart is a 10-centimeter by 10-centimeter square grid. Each side of the grid has 20 cells, and there’s a circular dot marking the grid’s center.

The Amsler grid eye test helps you see vision distortions (metamorphopsia) that can happen if you have certain conditions affecting your macula. The Amsler grid also helps you show an eye care specialist where the distortions are in your visual field. That lets them know where the problem is on your macula.

Eye specialists commonly recommend that people with certain retinal conditions use an Amsler grid daily. Doing so can help you see changes in your vision that may quickly turn into permanent vision loss.

When is the Amsler grid eye test used?

The Amsler eye grid test can help with diagnosing and monitoring any condition that could distort the surface of the macula. That includes:

• Macular degeneration (both the dry and wet types).
• Central serous retinopathy.
• Conditions that make new blood vessels form (neovascularization) in certain areas of your eye.
• Blind spots (scotomas).
• Macular pucker (epiretinal membrane).
• Cystoid macular edema.
• Diabetes-related macular edema.
• Pituitary gland tumors (these cause bilateral hemianopia, which is vision loss in the left half of your left eye and the right half of your right eye).
• Injury-related damage to the macula.
• Other retinal diseases or retina-related causes of sudden vision loss.

Experts can also use the Amsler grid as a screening tool to check for issues with your macula before you undergo cataract surgery.

How does the Amsler grid eye test work?

To use an Amsler grid, you first hold it at a normal reading distance, about 12 to 15 inches (30 to 38 centimeters) in front of you. If you wear glasses or contacts, be sure you’re wearing them before you proceed.

You test each eye individually, covering the unused eye. When you test an eye, focus on the dot at the very center of the grid. Make sure you hold the grid at the same distance each time you test an eye. While you’re focusing on the dot at the center of the grid — but without moving your eye — make sure the following are all true:

• You can see all four corners of the grid.
• You can see all the grid lines, and they all appear perfectly straight.
• The grid is free of any darker or blank areas.
• All the grid lines are clear and solid (not blurred or faded).

During in-office visits, your eye care specialist may use an Amsler grid to test your vision. If you’re at risk for retinal diseases or changes, they may also give you a printed Amsler grid to use at home.

If your eye specialist gives you a printed Amsler grid to take home, use it exactly as recommended (usually daily). If you notice any of the above four criteria aren’t true while using an Amsler grid to self-test your vision, call your eye care specialist right away.

What are the other Amsler eye grid types?

Marc Amsler, the Swiss ophthalmologist who created the Amsler grid eye test, made seven different versions (or charts) of this grid test. Most of the time, people mean chart 1 when they refer to this test.

The seven versions are:

• Chart 1: This is the main and most commonly used version, with black lines on a white background. There are 20 cells on each side of the grid, so each cell is 0.5 centimeters wide. In the center of the grid is a small circle for you to focus on.
• Chart 2: This is similar to chart 1, but it also has a diagonal line from each corner to the center dot. It helps people with blind spots in the center of their vision who are still using the grid test to monitor for vision changes.
• Chart 3: This version has the same structure as chart 1, but it uses red lines on a black background. It helps with seeing subtle, color-related vision distortions and changes.
• Chart 4: Instead of grid lines, the 10 cm x 10 cm square has random white dots dispersed inside, with a black background. Using dots instead of grid lines helps the viewer tell the difference between vision distortions and blind spots.
• Chart 5: This test has horizontal grid lines only, and the lines are white on a black background. The only vertical lines are the outer left and right walls of the square.
• Chart 6: Similar to chart 5, but with black lines on a white background. Also, the center horizontal line and the next two lines above and below are closer together than the rest of the lines in the grid. Lines that are closer together let you see smaller distortions and changes.
• Chart 7: This uses white grid lines on a black background. It’s similar to chart 1, but the center 5 cm x 5 cm grid switches to cells that are half as big as those in the outer sections of the grid. The smaller cells work similarly to the lines in chart 5 that are closer together, allowing you to see even smaller changes or distortions.

What does the Amsler grid look like if you have macular degeneration?

If you have macular degeneration, the Amsler grid may have areas that appear differently. They might look like any of the following:

• Grid lines that are wavy or blurry.
• Areas of the grid that are faded or darker.
• Areas of the grid that appear blank.

Are there smartphone or tablet Amsler grid apps?

There are Amsler grid apps available for smartphones and tablets. If you want to use one, talk to your eye care specialist. They can tell you if these apps will work for your needs. But always remember that a smartphone app isn’t a substitute for medical care. When in doubt, you should always see a trained, qualified eye specialist.

A note from Cleveland Clinic

The Amsler grid is a simple, quick and noninvasive way to check for distortions or changes in your vision. Your eye specialist may advise you to use a printed Amsler grid daily to watch for any changes in your central field of vision.

Using an Amsler grid as recommended can help with early detection of retinal changes from conditions like macular degeneration. Catching these changes early can help preserve your vision and prevent further damage, helping you continue relying on your eyes daily.