Macular degeneration is a deterioration or breakdown of the eye's macula. The macula is a small area in the retina — the light-sensitive tissue lining the back of the eye. The macula is the part of the retina that is responsible for your central vision, allowing you to see fine details clearly. The macula makes up only a small part of the retina, yet it is much more sensitive to detail than the rest of the retina (called the peripheral retina). The macula is what allows you to thread a needle, read small print, and read street signs. The peripheral retina gives you side (or peripheral) vision. If someone is standing off to one side of your vision, your peripheral retina helps you know that person is there by allowing you to see their general shape.
The most common form of juvenile macular degeneration is Stargardt disease. Other types of juvenile macular degeneration include Best’s disease (also called Best’s vitelliform retinal dystrophy), and juvenile retinoschisis. All of these diseases are rare and cause central vision loss. Unfortunately, there is no treatment available to prevent vision loss.