Description of the Ansler Grid:

The Amsler grid is a tool that eye doctors use to detect vision problems resulting from damage to the macula (the central part of the retina) or the optic nerve. The damage may be caused by macular degeneration, glaucoma, or other eye diseases, so the Amsler grid is useful in detecting these problems.
An early diagnosis means early treatment, so it may help to limit or at least slow the vision loss you experience.
If you are at risk for macular degeneration or other eye diseases, you can use this chart at home to monitor your vision. But using the chart doesn't mean you should skip regular visits to your eye doctor, because you can easily miss signs that only a trained eye care practitioner will find.
The chart to the right is an approximation of the printed chart used by eye doctors. For more accurate detection of macular damage, you will need a complete eye exam.

If you have never used the Amsler Grid before:
How to use the Amsler Grid