Figure 1.
Diagram of the fixation target system.
A 1.2 m long optical rail was installed upon a lift table, and placed beside the slit lamp, fixed by a Philips 17-inch LCD monitor on a slider for displaying the target. This LCD monitor was able to move along the optical rail to adjust the distance between the visual target and the human eye, to induce a different stimulus of accommodation. In order to allow the subjects to fix on the target, without being affected by the moving probe, a plane mirror was installed on the slit lamp column, so that the target was projected into the eye after specular reflection.
Figure 2.
OCT images of ocular anterior segment on horizontal (A) and vertical (B) meridians.
The values of dimensional parameters were obtained from the images using custom software. Anterior chamber depth (ACD) and lens thickness (LT) were measured along the perpendicular line. Pupil diameter (PD) was measured along the horizontal line from both ends of the iris. The radii of anterior and posterior surface curvatures of the crystalline lens (ASC/PSC) were measured from the two surfaces of the lens.
Figure 3.
The comparison of OCT images obtained before (left) and after (right) accommodation on horizontal and vertical meridians.
Table 1.
Anterior Segment Dimensions at the Horizontal and Vertical Meridians during accommodation.
Table 2.
Repeated Measurements of the Anterior Segment Dimensions.