IMPROVED VISUALIZATION OF CHOROIDAL BLOOD FLOW AND ABERRANT VASCULAR STRUCTURES IN THE EYE

摘要

A method of visualizing the choriocapillaries of the eye in a sequence of ICG angiographic images comprising subtracting each image in the angiographic sequence from a succeeding image. In practice, a modified fundus camera (10) is used to provide digitized images which are subtracted pixel by pixel. To better visualize aberrant vascular structures such as choroidal neovascularization (CNV), a fundus camera (22) is modified with a polarizing filter (24) in front of the light source (26) and an analizing polarizer (28) in front of the video camera (30). This results in the suppression of unwanted scattered fluorescence to the exent that the CNV can be better visualized. To assist the surgeon in treating aberrant vascular structures with laser photocoagulation therapy, a fundus camera (32) is provided with two light sources (42, 44) and two barrier filters (46) operating synchronously to produce and pass two different fluorescences thereby generating precisely superimposable angiographs to aid in aiming the laser.