Measurement of Iris Thickness at Different Regions in Healthy Chinese Adults

Figure 1

Measurements of iris thickness at 199 points. (a) Scleral spurs (SS) at both sides were identified; vertical lines through the SS that were perpendicular to the lines connecting the two SS, together with the anterior and posterior iris surface, defined the border of the iris. (b) After the background bitmap was removed, the iris was rotated so that the line connecting the end of the lateral anterior iris surface and pupillary margin (^∗) became horizontal. (c) The image was recalibrated, and two horizontal lines parallel to the line connecting the anterior iris root and pupillary margin were drawn above and below the iris as references. (d) The iris was then divided into 200 sections by 199 equally spaced vertical lines across the iris with a specially edited path in the Grasshopper plug-in. The iris thickness was defined as the length of the vertical line between the anterior and posterior borders of the iris, point 1 referred to the first location from the lateral side, point 2 was the second, and the rest was deduced by analogy.

(a)

(b)

(c)

(d)