Figure 1

Facial landmarks for measurement. We calculated (the distance between p1 and p2)/(the distance between p1 and p3) for the vertical forehead-to-face ratio, (the distance between p6 and p7)/(the distance between p1 and p3) for the vertical eye-to-face ratio, and (the distance between p6 and p7)/(the distance between p4 and p5) for the roundness of the eye. Eye size was calculated separately for the right and the left eye.