Trajectories of retinal arteries.

<p>The fundus photograph was rotated 90 degrees clockwise for the right eye and 90 degrees counterclockwise for the left eye (A and B). The retinal arteries were marked by at least 20 points. The coordinates of the marked spots were determined automatically using ImageJ software and converted to a new set of data with the center of the optic disc as the origin. The converted coordinate data were fit to a user-defined second degree polynomial equation (ax²/100 + bx + c) (C and D).