There are many eye diseases and disorders, some mild to very severe. One example of a disease would be Macular Degeneration. Macular Degeneration is the deterioration of the central portion of the retina, known as the macula. This disease is the leading cause of blindness in people of the age of 55. There are two types of Macular Degeneration, dry and wet. Dry (atrophic), when small yellow deposits form under the macula, causing it the thin and dry out, leading to central vision loss. Wet is when abnormal new blood vessels grow under retina and macula. This may cause bleeding and a leak of fluid causing the macula to bulge or lift up, damaging or destroying the central vision. Vision loss may be rapid and severe.
Another disorder is Glaucoma.
Another disorder is Glaucoma.