The particular AF image quality used to calculate MPOD levels varied from relatively high quality to poor depending on the degree of the lens opacity, with the corresponding CF expected to increase accordingly. We subjectively classified preoperative AF images into three groups: relatively high quality (
Fig. 1a), moderate quality (
Fig. 1b), and poor quality (
Fig. 1c). Typically, the SDs of the MPOD levels (widths of plots) were smaller for the relatively high-quality images and larger for the degraded images. In the case of
Figure 1a, the relative SDs of the local MPOD levels at 0.23°, 0.98°, and 1.99° eccentricity are 0.12, 0.13, and 0.23, respectively, before surgery, and 0.08, 0.07, and 0.12 after surgery. Before surgery, the eye lens had a grade 1 NUC, grade 3 COR, grade 0 PSC, and a cortical opacity involving the CEN. The E-L classification was grade 1. The CFs for the local MPOD levels at these three eccentricities were 1.26, 1.15, and 1.14, respectively. In the case of
Figure 1b, the relative SDs were 0.33, 0.26, and 0.38 before surgery and 0.15, 0.13, and 0.16 after surgery. This eye lens had a grade 0 NUC, grade 3 COR, grade 2 PSC, and cortical opacity involving the CEN. The E-L classification was grade 1. The CFs for the local MPOD levels were 1.36, 1.24, and 1.31, respectively. In the case of
Figure 1c, the relative SDs were 0.44, 0.44, and 0.48 before surgery and 0.11, 0.13, and 0.13 after surgery. This eye had a grade 1 NUC, grade 3 COR, grade 0 PSC, and cortical opacity involving the CEN. The E-L classification was grade 1. The CFs for the local MPOD levels were 1.73, 1.82, and 1.41, respectively. Therefore, we utilized the SDs of the MPOD levels as a quantitative measure for image quality.