Screening for Research Participants

This study will allow National Eye Institute (NEI) doctors the opportunity to examine people with eye disease, whether the diagnosis is known or not, to determine if they are eligible for other NEI research studies. No treatment is offered in this study. People of all ages with various eye conditions, including genetic conditions, eye movement disorders, inflammatory eye diseases, retinal diseases and external eye diseases, may be eligible for this study. Participants undergo various tests and procedures to diagnose or evaluate their eye disease. The procedures may include the following: * Personal and family medical history * Physical examination and blood tests, including genetic testing. * Eye examination with dilation to measure visual acuity and eye pressure and to examine the front and back parts of the eye. * Questionnaire about vision and daily activities. * Conjunctival swab or lacrimal bland biopsy, or both: A sample of cells from the eyes is collected by swabbing the surface of the eye or by surgically removing a small sample of the surface of the eye or tear gland. * Electroretinogram to examine retinal function: The subject sits in the dark with his or her eyes patched for 30 minutes. The patches are removed, the surface of the eyes is numbed, and contact lenses that can sense signals from the retina are placed on the eyes. The subject then watches flashing lights. * Fluorescein angiography to examine the blood vessels in the eye: A dye is injected into a vein in the arm. The dye travels through the veins to the blood vessels in the eyes. A camera takes pictures of the dye as it flows through the blood vessels. * Optical coherence tomography to measure retinal thickness: A machine used to examine the eyes produces cross-sectional pictures of the retina. * Microperimetry to test how sensitive different parts of the retina are to changing levels of light. The subject sits in front of a computer and presses a button when he or she sees a light on the sc