Fig. 3
From: A novel method of quantifying retinal vascular tortuosity in retinopathy of prematurity
Comparison of average retinal vessel tortuosity between the Normal and Abnormal groups. The horizontal axis represents the diameter of the circular region of interest defined as a multiplier of the optic disc diameter. A multiplier of 8 approximately corresponds to a circular region with its radius as the disc-to-fovea distance, while a multiplier 14 corresponds approximately to the boundary of Zone I in retinopathy of prematurity (ROP). The vertical axis shows the average tortuosity measured in degrees. Statistically significant differences in the average tortuosity between the two groups were observed at multipliers and above (* p < 0.05). Data at multiplier 20 were insufficient for analysis due to insufficient peripheral vessel image resolution.
