Table 1 Comparison of morphometric parameters for the ICA bifurcation among the patient groups

α angle (^o)

116.4 ± 18.7

114.8 ± 15.4

119.4 ± 18.4

120.7 ± 26.4

120.2 ± 14.8

119.1 ± 14.7

NS

Φ₁ angle (^o)

44.9 ± 31.3

39.9 ± 30.3

35.6 ± 16.8

45.6 ± 19.2

41.7 ± 20.4

40.4 ± 20.6

NS

Φ₂ angle (^o)

88.2 ± 28.2

86.8 ± 27.4

96.0 ± 13.8

93.2 ± 15.6

95.0 ± 17.4

92.5 ± 19.1

NS

r₀, mm

1.86 ± 0.24

1.85 ± 0.20

1.92 ± 0.23

1.91 ± 0.23

1.85 ± 0.23

1.82 ± 0.22

NS

r₁, mm

1.48 ± 0.21

1.48 ± 0.18

1.53 ± 0.19

1.48 ± 0.23

1.49 ± 0.22

1.46 ± 0.23

NS

r₂, mm

1.12 ± 0.22

1.13 ± 0.17

1.16 ± 0.21

1.17 ± 0.24

1.15 ± 0.25

1.13 ± 0.26

NS

asymmetry ratio, r₂²r₁^− 2

0.59 ± 0.18

0.60 ± 0.17

0.59 ± 0.16

0.64 ± 0.20

0.62 ± 0.19

0.62 ± 0.20

NS

area ratio, (r₁²+r₂²)r₀^− 2

1.02 ± 0.21

1.03 ± 0.19

1.03 ± 0.23

1.00 ± 0.23

1.05 ± 0.21

1.04 ± 0.21

NS

n, junction exponent

2.28 ± 0.91

2.25 ± 0.78

2.38 ± 1.15

2.20 ± 0.78

2.40 ± 0.99

2.28 ± 0.76

NS

(ϕ₁ + ϕ₂) - α angle (^o)

−57.2 ± 29.8

−59.5 ± 26.7

−60.3 ± 26.9

−65.4 ± 25.8

− 59.9 ± 29.2

−57.1 ± 28.5

NS

ϕ₁ - Φ1 angle (^o)

−23.4 ± 28.9

−25.7 ± 32.5

−13.0 ± 18.1

−18.8 ± 18.6

−19.0 ± 20.5

−19.4 ± 21.4

NS

ϕ₂ - Φ2 angle (^o)

−50.1 ± 32.3

−47.2 ± 34.4

−61.6 ± 20.0

−63.7 ± 21.3

−57.8 ± 23.1

−54.1 ± 24.5

NS