Here is a simple test that can be performed anytime to check whether you sight is deteriorating. It involves rapidly blinking one eye, while covering the other eye, and looking at some neutral object such as a white wall. I have rendered the two following graphics to show you what I see when I try this test.
The picture to the right is a simulated representation of the post retinal image as interpreted by the brain. After I blink, I notice that there is a latent image of a blotchy disc. The dark areas represent leaked blood that the fovea must look through and the lighter areas represent looking through a mass of scar tissue. The colors range from black-brown to yellow with fuzzy areas at the edges. No discernible shapes are recognized through this blob.
This one represents a lower source of brightness such as a darker wall. If you see these post retinal images when you blink, then its time to see an ophthalmologist and have your eyes thoroughly examined to see if you are starting to get some form of age-related macula degeneration. If you leave it too long then there is little that can be done to halt the process. Most people never really notice its happening until its too late.
Another test often performed while at the ophthalmologists office is called the AMSLER grid test. You cover one eye at a time and look at the dot in the center of the page. If you see a fuzzy or missing area or any wavy distortion or bending of the lines then you have some sort of aberration in your macula. Tell the doctor who will note on the graph the area in question for future reference. This small sample of an AMSLER grid chart can be downloaded in 8.5x11 full size suitable for printing out on your printer. Depending upon your screen size you may want to turn it into the default wallpaper for your monitor. Then you can test yourself every time you turn your computer on. It's amazing how many people inquire about your picture and learn about AMD.
Find out more information about Amsler Test, as well as instructions and printable PDF.
Click on the chart to display it them print it out. (6Kb)
The common eye chart that you see at the eye doctors clinic gives an indication of a persons visual acuity in terms of two numbers, such as 20/100. This means you can see at 20 feet the same thing that a normal sighted person can see at 100 feet. The higher the second number, the worse your sight is. Normal sight is rated at 20/20. I have found a web site that offers an interactive acuity test you can run on line. It was conceived by Scott Olitsky, MD and designed and implemented by Henry Lee and Edward Young. Click on the eye chart to go there.