Color Vision as a Measure for Inherited Retinal Diseases

Background: \- The purpose of this study is to find out whether color vision measured with the Cambridge Color Test is a good way to examine the severity of inherited retinal diseases (IRDs). IRDs are a major cause of vision loss worldwide, but very little is known about how the diseases affect color vision over time. This study will tell us if color vision may be used to track changes in inherited retinal diseases over time. Objectives: \- To improve understanding of color vision as a way to measure changes in inherited retinal diseases. Eligibility: * People 5 years of age or older who have an IRD. * Healthy volunteers at least 5 years of age. Design: * Participants will make at least one visit to the National Eye Institute clinic. If they sign up for more tests, they may have up to three visits to the NEI clinic. * Participants will be asked questions about their medical and eye history. * Participants will be given an eye exam, including eye drops to dilate their pupils. They will take the Cambridge Color Test, which includes looking at a monitor and pressing a button, and arranging colored circles. Several other tests may be offered, but participants can decline to take them. * Treatment will not be provided as part of this study.