People who have sickle cell disease can sometimes have vision problems. Blood cells that change shape or "sickle" can get trapped in blood vessels, blocking the blood flow. When this blockage occurs in the small blood vessels in the inner lining (retina) of the eyes it can cause vision problems. This most often occurs in people who have hemoglobin SC disease, a type of sickle cell disease.
In the worst cases, the retina may come loose, leading to permanent blindness. This may happen suddenly, without any warning.
Children older than age 10 who have sickle cell disease should have an eye exam every year. This exam needs to be done by an ophthalmologist, a medical doctor who specializes in eye problems.
WebMD Medical Reference from Healthwise