The Topographical Effect of Optical Zone Diameter in Orthokeratology Contact Lenses in High Myopes
Table 3
Mean corneal radius differences along the horizontal axis between baseline (before orthokeratology wear) and day 15 for 5 mm and 6 mm OZ lens designs (baseline − 15 d).
Lens design
Parameter (mean ± SD)
Corneal radius (baseline − PRE)
OZ 5 mm lens
Distance to apex (mm)
−4.00
−3.00
−2.00
−1.00
0.00
1.00
2.00
3.00
4.00
1 day
−0.04 ± 0.20
0.101 ± 0.19
0.24 ± 0.12
−0.16 ± 0.10
−0.38 ± 0.13
0.07 ± 0.08
0.28 ± 0.09
−0.13 ± 0.27
−0.11 ± 0.40
7 days
0.02 ± 0.38
0.69 ± 0.29
0.30 ± 0.16
−0.66 ± 0.20
−0.84 ± 0.07
0.11 ± 0.15
0.69 ± 0.19
−0.09 ± 0.39
−0.73 ± 0.82
15 days
0.15 ± 0.44
0.86 ± 0.36
0.19 ± 0.22
−0.70 ± 0.18
−0.81 ± 0.10
0.00 ± 0.20
0.76 ± 0.27
0.15 ± 0.41
−1.11 ± 1.11
OZ 6 mm lens
Distance to apex (mm)
−4.00
−3.00
−2.00
−1.00
0.00
1.00
2.00
3.00
4.00
1 day
−0.22 ± 0.36
0.30 ± 0.22
0.13 ± 0.12
−0.18 ± 0.10
−0.28 ± 0.15
−0.04 ± 0.17
0.30 ± 0.12
0.01 ± 0.31
−0.22 ± 0.37
7 days
−0.17 ± 0.29
0.65 ± 0.43
0.16 ± 0.21
−0.48 ± 0.17
−0.57 ± 0.19
−0.07 ± 0.29
0.53 ± 0.22
0.08 ± 0.59
−0.81 ± 1.14
15 days
−0.31 ± 1.51
0.77 ± 0.48
0.09 ± 0.26
−0.57 ± 0.31
−0.56 ± 0.12
−0.12 ± 0.28
0.56 ± 0.28
0.18 ± 0.67
−0.95 ± 1.10
Negative values mean flattening and positive values mean steepening. OZ: optical zone; SD: standard deviation.
