Relationship of Retinal Vessel Caliber with Age-Related Macular Degeneration

Figure 1

Automated segmentation of retinal vessel diameters from AREDS fundus photographs. The IVAN measurement grid consists of 3 concentric rings with the area of vessel measurement located 0.5 to 1.0-disc diameters away from the optic disc margin. Masked graders correct the automated measurements by adjusting grid centration, manually adding, or deleting vessels, and assigning the appropriate vessel type. Arterioles are displayed in red and venules in blue. Vessels are only measured up until the first branching point within the zone of measurement.