Fluorescent dye for ophthalmological diagnosis is injected in

The technique of FFA comprises rapidly injecting 5 ml of 10 percent solution of sterile sodium fluorescein dye in the antecubital vein and taking serial photographs (with fundus camera) of the fundus of the patient who is seated with pupils fully dilated. The fundus camera has a mechanism to use blue light (420-490 nm wavelength) for exciting the fluorescein present in blood vessels and to use the yellow-green filter for receiving the fluorescent light (510-530 nm wavelength) back for photography. Reference : A K KHURANA Comprehensive Ophthalmology; edition 4; page-487