[An analyzing system for fluorescein angiography of retinal blood flow using a high speed, high sensitivity camera]

We constructed a speedy and sensitive fundus camera system, and developed a new method to analyze retinal blood flow in rabbits and monkeys. The system is composed of a fluorescein fundus camera (TRC-50X, Topcon), a relay lens, an image intensifier (Ektapro-intensified-imager, Kodak), a digital recorder (Ektapro-EM, Kodak), an S-VHS analogue recorder, a picture analyzer (IMAGEnet, Topcon), and a CRT (cathode-ray tube) monitor. The speed of retinal blood flow in rabbits is calculated by measuring the time and distance between two points of an advancing illumined fluorescein dye front in a vessel. The speed in monkeys is obtained by analysis using an autocorrelative function, instead of the method used with rabbits, because of background fluorescein noise and vessel tortuousity.