Table 3 Mean arithmetic values and power vectors for total corneal refractive power within 2.0–5.0 mm zones

Centered on pupil

Mean keratometry (diopter)

44.43 ± 1.53

44.52 ± 1.38

44.66 ± 1.25

44.76 ± 1.15

0.06

49.81 ± 4.87

49.31 ± 4.25

48.75 ± 3.58

48.12 ± 2.97

< 0.001

Mean

arithmetic

astigmatism (diopter)

2.33 ± 1.04

2.72 ± 0.95

2.84 ± 1.07

2.86 ± 1.23

0.001

4.44 ± 2.62

5.07 ± 2.23

5.15 ± 2.05

4.92 ± 2.10

0.037

KP(0) (diopter)

−1.03 ± 1.79

− 1.49 ± 1.90

−1.82 ± 1.91

−2.08 ± 1.82

< 0.001

− 2.44 ± 3.20

− 3.05 ± 3.53

− 3.32 ± 3.58

− 3.34 ± 3.51

< 0.001

KP(45) (diopter)

0.89 ± 1.27

1.02 ± 1.27

0.99 ± 1.20

0.97 ± 1.11

0.012

1.48 ± 2.92

1.33 ± 2.75

1.04 ± 2.49

0.77 ± 2.21

0.002

Centered on apex

Mean keratometry (diopter)

45.07 ± 1.55

45.08 ± 1.40

45.12 ± 1.28

45.14 ± 1.21

0.92

51.41 ± 5.56

50.66 ± 4.81

49.83 ± 3.99

48.94 ± 3.21

< 0.001

Mean

arithmetic

astigmatism (diopter)

3.09 ± 1.55

3.07 ± 1.25

3.02 ± 1.10

2.90 ± 1.12

0.93

6.13 ± 2.88

5.69 ± 2.52

5.12 ± 2.24

4.54 ± 2.05

< 0.001

KP(0) (diopter)

−1.37 ± 2.52

−1.57 ± 2.33

−1.81 ± 2.16

−1.94 ± 1.99

0.23

− 3.52 ± 4.35

−3.37 ± 3.97

−3.14 ± 3.59

−2.85 ± 3.24

0.68

KP(45) (diopter)

1.22 ± 1.57

1.16 ± 1.40

1.04 ± 1.24

0.92 ± 1.10

0.18

1.91 ± 3.39

1.64 ± 3.06

1.37 ± 2.64

1.11 ± 2.29

0.021

0.041

< 0.001

< 0.001

< 0.001

0.002

< 0.001

< 0.001

< 0.001

< 0.001

0.004

0.054

0.76

< 0.001

0.001

0.98

0.076

0.091

0.72

0.95

0.046

0.011

0.094

0.13

0.003

0.022

0.44

0.80

0.55

0.023

0.016

0.006

0.006