<unk>  <unk> ,<unk> t<unk>  <unk> , or fundus<unk>  (FFA) is a technique for examining the circulation of the retina and choroid (parts of the fundus) using a<unk> t dye and a specialized camera. Sodium<unk>  is added into the systemic circulation, the retina is illuminated with blue light at a wavelength of 490 nanometers, and an angiogram is obtained by photographing the<unk> t green light that is emitted by the dye. The<unk>  is administered intravenously in intravenous<unk>  (IVFA) and orally in oral<unk>  (OFA). The test is a dye tracing method. The<unk>  dye also reappears in the patient urine, causing the urine to appear darker, and sometimes orange. It can also cause discolouration of the saliva.<unk>  is one of several health care applications of this dye, all of which have a risk of severe adverse effects. See<unk>  safety in health care applications.<unk>  does not involve the use of ionizing radiation.<unk>  was pioneered by German ophthalmologist Achim Wessing, who published his findings in 1969.
Fluorescein angiography
Laser speckle contrast imaging
Doppler optical coherence tomography
Optical coherence tomography angiography
OCT Biomicroscopy
Speckle variance optical coherence tomography
Retinal birefringence scanning
Laser Doppler imaging