RP stands for retinitis pigmentosa, which is a hereditary disease that attacks the rods and cones of the retina, resulting in loss of night vision and peripheral vision, and eventually leading to blindness.

It is similar to macular degeneration, which affects 1 in 4 of our aging population, but macular degeneration takes vision from the inside out, and RP takes it from the outside in. A person with RP has difficulty maneuvering in the dark and advanced RP causes severe tunnel vision, with the central vision eventually becoming blurry and going as well. To imagine what it is like for a person with RP, hold a paper towel cardboard to your eye. What you see is clear, but you only see what is directly in front of you. It is as if nothing else is there. This is why Sharyn can read a book, but cannot safely drive a car. Also, you note that you see a great deal more when looking at something a distance away, but if looking at something close to you, you will see very little at all. With time, this circle of vision grows smaller as the disease progresses. While RP is a relatively rare disease, there are many forms of it, with varying rates of vision loss. There is currently no cure for RP and the only available treatment is large doses of vitamin A to slow the progress of the disease. However, recent research is very promising and holds great hope for future treatments and cures.