FLUORESCEIN ANGIOGRAPHY Fluorescein Angiography is a diagnostic test that provides visualization of the retinal blood circulation. This test provides the ophthalmologist with information that can be obtained with no other testing modality. Sodium fluorescein dye is injected into a vein in the arm or hand of the patient. As the dye travels through the circulatory system of the body, a retina camera with special filters in place is used to photograph the transit of the dye through the retinal circulation. The particular characteristics of the circulation in the various diseases of the retina provide diagnostic and treatment information. The technique of retinal fluorescein angiography was developed by Drs. Harold Novotny and David Alvis in 1961. The basic technique has remained unchanged, but improvements in photographic instrumentation have improved the quality of the imaging. Sodium fluorescein was invented by Adolf Baeyer (the Bayer aspirin fellow) in 1871, and was first used as a textile dye. It is commonly thought to be a vegetable dye, but is actually a mineral based synthetic dye distilled from coal tar. When injected into the bloodstream, the yellowish fluorescein solution binds with serum protein. The fluorescein/serum solution is able to absorb blue light and the electrons are elevated by the blue light to a higher energy state. As the excited molecules return to the previous state, the yellowgreen light known as fluorescence is given off. It is this fluorescent light that we capture on film.