Femtosecond Laser Implantation of a 355-Degree Intrastromal Corneal Ring Segment in Keratoconus: A Three-Year Follow-Up
Table 4
Comparison between preoperative and postoperative K max, K min, and K mean measures.
Preoperative
3 months postoperative
6 months postoperative
12 months postoperative
24 months postoperative
36 months postoperative
value
P1
P2
K max
Mean ± SD
53.82 ± 4.1
47.48 ± 2.16
47.44 ± 2.11
48.04 ± 2.39
49.51 ± 3.73
50.47 ± 4.08
<0.001
<0.001
0.001
Median (range)
54.6 (47.6–61.2)
48 (43–52)
47.3 (44–51.3)
47.75 (44.2–56.1)
48.95 (44.1–61.5)
49.5 (44.5–62)
K min
Mean ± SD
48.83 ± 2.84
45.23 ± 1.99
45.41 ± 1.82
45.8 ± 2.13
46.53 ± 2.46
47.01 ± 2.4
<0.001
<0.001
0.001
Median (range)
49.5 (45–53.2)
45.05 (42–48)
45.75 (41.9–48)
45.6 (42–50)
46 (42.7–55)
46 (43–55)
K mean
Mean ± SD
51.29 ± 3.49
46.29 ± 1.48
46.17 ± 1.67
46.57 ± 1.62
47.12 ± 1.62
47.51 ± 1.95
<0.001
0.001
0.055
Median (range)
52.95 (46–56)
46.6 (43.8–48.4)
46.6 (43–48)
46.55 (43.8–49)
47.35 (44–50)
47.6 (44–52)
value compared the six repeated measures and was calculated by Friedman’s two−way ANOVA test.P1 compared 12 months postoperative and 24 months postoperative measures and was calculated by the Wilcoxon signed-rank test.P1 compared 24 months postoperative and 36 months postoperative measures.
