An Amsler chart can help you monitor your eyesight
How To Test Yourself with the Amsler Grid
Place this the Amsler Grid chart at eye level where light is consistent and without glare.
Put on your reading glasses and cover one eye.
Fix your gaze on the central black dot.
Keeping your gaze fixed, try to see if any lines are distorted or missing.
Marked the defect on the chart.
Test each eye separately.
If the distortion is new or has worsened, arrange to see your ophthalmologist urgently
Always keep the Amsler chart the same distance from your eyes each time that you test.
Note: If you need reading glasses, please wear them while you use the Amsler grid. The grid should be at about the same distance from your eyes that any other reading material would be.