A method is described to determine the total retinal blood flow. Intravenous fluorescence angiography is the clinical procedure used, together with digital image processing methods. Our system consists of a standard fundus camera, a highly sensitive sensor with a low-light-level intensifier (micro-channal plate) and a CCD, a computer system including a real-time memory, an image display subsystem, and other standard peripherals (disk, magtape, terminal, etc.). The recording speed is 100 frames (noninterlaced), the image size 256 X 256 pixels, and the depth 8 bit. In order to properly track the images against the patients eye movements, it is necessary to have absolutely sharp pictures. The fundus camera is therefore equipped with a stroboscopic bulb, which gives light pulses of 0.01 ms. The stroboscope is synchronized by the electronics of the camera. After recording the images, further evaluation is done.
Blood Flow Velocity Fluorescein Angiography