Table 1 Visual, refractive and tomographic parameters of patients who were implanted with single ICRS (Group 1) and double ICRS (Group 2)

UDVA (Snellen lines)

0.11 ± 0.10

0.09 ± 0.09

0.67

0.41 ± 0.24

0.35 ± 0.23

0.34

0.31 ± 0.22

0.26 ± 0.25

0.45

CDVA (Snellen lines)

0.35 ± 0.20

0.29 ± 0.12

0.13

0.64 ± 0.25

0.56 ± 0.20

0.14

0.29 ± 0.21

0.27 ± 0.20

0.69

Spherical refraction (D)

−2.48 ± 3.73

−4.19 ± 4.49

0.16

−1.76 ± 3.41

−2.69 ± 2.97

0.28

0.49 ± 2.70

1.39 ± 4.25

0.38

Cylindrical refraction (D)

−4.98 ± 2.13

−5.68 ± 2.67

0.32

−2.12 ± 1.54

−2.39 ± 1.67

0.56

2.50 ± 2.17

3.52 ± 2.97

0.17

SE of refractive error (D)

− 4.73 ± 4.31

−7.03 ± 4.06

0.05

−2.77 ± 3.64

−3.70 ± 3.18

0.32

1.74 ± 2.71

3.15 ± 4.31

0.18

SimK_avg (D)

49.10 ± 3.67

51.37 ± 3.68

0.03*

47.13 ± 3.90

48.29 ± 3.08

0.21

−1.98 ± 1.90

−3.11 ± 2.05

0.04*

SimK_f (D)

47.17 ± 3.93

48.78 ± 3.95

0.14

45.76 ± 3.72

47.19 ± 3.12

0.12

−1.40 ± 1.56

−1.51 ± 2.39

0.85

SimK_s (D)

51.67 ± 4.41

54.30 ± 3.61

0.02*

48.61 ± 4.15

49.47 ± 3.19

0.38

−3.06 ± − 1.56

−4.83 ± 2.19

< 0.01*

Central pachymetry (μm)

461.73 ± 41.65

444.92 ± 47.91

0.18

479.0 ± 48.39

457.11 ± 50.09

0.11

17.27 ± 13.86

12.18 ± 18.75

0.28

Thinnest pachymetry (μm)

440.68 ± 44.27

432.82 ± 49.69

0.55

463.59 ± 46.53

434.82 ± 55.01

0.05

22.91 ± 17.39

2.00 ± 35.23

0.01*

Q_ant

−0.91 ± 0.47

−1.12 ± 0.39

0.07

−0.61 ± 0.51

−0.57 ± 0.52

0.79

0.30 ± 0.22

0.56 ± 0.44

0.01*

Q_post

−0.92 ± 0.46

−1.11 ± 0.56

0.19

−0.86 ± 0.43

−1.13 ± 0.56

0.07

0.06 ± 0.15

0.00 ± 0.50

0.64

ISV

95.41 ± 35.20

91.39 ± 28.93

0.64

75.18 ± 30.19

82.19 ± 29.87

0.40

−20.23 ± 13.67

−11.37 ± 21.53

0.09

IVA

0.99 ± 0.43

0.70 ± 0.39

0.01*

0.73 ± 0.41

0.72 ± 0.40

0.88

−0.25 ± 0.20

−0.01 ± 0.26

< 0.01*

KI

1.26 ± 0.12

1.20 ± 0.12

0.09

1.18 ± 0.12

1.13 ± 0.13

0.16

−0.08 ± 0.05

−0.10 ± 0.20

0.59

CKI

1.07 ± 0.05

1.09 ± 0.05

0.18

1.06 ± 0.05

1.10 ± 0.06

0.01*

−0.01 ± 0.03

0.02 ± 0.19

0.93

IHA

19.06 ± 23.40

26.76 ± 20.96

0.20

22.22 ± 15.37

27.14 ± 19.50

0.32

3.16 ± 23.87

0.33 ± 23.84

0.59

IHD

0.14 ± 0.07

0.10 ± 0.07

0.05

0.10 ± 0.06

0.09 ± 0.05

0.78

−0.04 ± 0.03

−0.01 ± 0.04

0.01*

Rmin (mm)

5.98 ± 0.71

5.74 ± 0.61

0.18

6.22 ± 0.76

5.96 ± 0.56

0.14

0.24 ± 0.29

0.06 ± 0.89

0.36

TKC

2.68 ± 0.83

2.64 ± 0.58

0.85

2.44 ± 0.54

2.26 ± 0.55

0.28

−0.55 ± 0.50

−0.45 ± 0.79

0.61

ACD (mm)

3.61 ± 0.42

3.43 ± 0.39

0.10

3.46 ± 0.50

3.30 ± 0.39

0.18

−0.15 ± 0.25

−0.22 ± 0.57

0.60

ACV (mm³⁾

190.30 ± 47.84

177.05 ± 26.24

0.18

178.0 ± 31.30

174.86 ± 24.62

0.71

−52.76 ± 86.87

−43.61 ± 75.52

0.68