Parameters affecting different acoustic radiation force impulse applications in the diagnosis of fibrotic liver changes

Table 3 Shear wave velocities of different age, body-mass index, and fasting groups and of women with and without oral contraceptives

		mean ± STD or median (range) (m/s)
		6C1-50 mmR	9L4-15 mmR	9L4-25 mmR	9L4-15 mmL
Age group (yr)	18-23 (n = 69)	1.28 ± 0.22	1.29 ± 0.24	1.19 ± 0.20	1.51 ± 0.27
		1.23 (0.95-1.91)	1.27 (0.81-1.82)	1.18 (0.64-1.68)	1.50 (0.79-2.31)
	24-29 (n = 57)	1.28 ± 0.20	1.25 ± 0.25	1.22 ± 0.19	1.53 ± 0.27
		1.26 (0.97-1.97)	1.22 (0.88-1.79)	1.23 (0.77-1.59)	1.52 (0.83-2.12)
	30-50 (n = 39)	1.25 ± 0.18	1.38 ± 0.32	1.22 ± 0.23	1.48 ± 0.35
		1.21 (0.98-1.75)	1.29 (0.88-2.30)	1.18 (0.82-1.83)	1.46 (0.90-2.67)
	> 50 (n = 21)	1.19 ± 0.20	1.57 ± 0.44	1.16 ± 0.25	1.64 ± 0.33
		1.12 (1.00-1.85)	1.55 (1.03-2.57)	1.17 (0.72-1.73)	1.65 (0.99-2.31)
BMI group (kg/m2)	< 20.00 (n = 30)	1.35 ± 0.25	1.35 ± 0.24	1.30 ± 0.19	1.57 ± 0.24
		1.29 (0.98-1.97)	1.39 (0.94-1.82)	1.29 (0.85-1.68)	1.59 (1.00-2.12)
	20.00-20.99 (n = 30)	1.20 ± 0.15	1.34 ± 0.28	1.28 ± 0.23	1.60 ± 0.29
		1.21 (0.97-1.60)	1.34 (0.88-2.01)	1.20 (0.95-1.83)	1.51 (1.00-2.24)
	21.00-21.99 (n = 36)	1.21 ± 0.18	1.23 ± 0.22	1.21 ± 0.20	1.50 ± 0.31
		1.16 (0.97-1.65)	1.19 (0.89-1.72)	1.15 (0.98-1.67)	1.47 (0.83-2.67)
	22.00-22.99 (n = 28)	1.29 ± 0.22	1.25 ± 0.23	1.18 ± 0.20	1.59 ± 0.32
		1.23 (1.06-1.84)	1.25 (0.81-1.71)	1.20 (0.80-1.47)	1.59 (1.14-2.31)
	23.00-23.99 (n = 24)	1.25 ± 0.15	1.30 ± 0.36	1.15 ± 0.19	1.34 ± 0.27
		1.25 (0.95-1.67)	1.16 (0.88-2.30)	1.18 (0.64-1.54)	1.36 (0.79-1.77)
	24.00-25.00 (n = 20)	1.29 ± 0.19	1.34 ± 0.25	1.10 ± 0.16	1.47 ± 0.28
		1.24 (1.03-1.88)	1.31 (0.97-1.94)	1.09 (0.77-1.43)	1.52 (0.90-1.89)
	> 25.00 (n = 18)	1.26 ± 0.25	1.63 ± 0.46	1.12 ± 0.23	1.59 ± 0.29
		1.16 (1.00-1.85)	1.56 (1.05-2.57)	1.16 (0.72-1.50)	1.61 (0.99-2.07)
Fasting time (h)	3.0 (n = 54)	1.28 ± 0.23	1.30 ± 0.33	1.21 ± 0.25	1.50 ± 0.33
		1.22 (0.98-1.97)	1.22 (0.81-2.56)	1.17 (0.64-1.83)	1.54 (0.83-2.31)
	3.5-7.0 (n = 66)	1.22 ± 0.19	1.37 ± 0.28	1.19 ± 0.20	1.59 ± 0.28
		1.20 (0.97-1.91)	1.34 (0.88-2.30)	1.18 (0.77-1.65)	1.51 (1.06-2.67)
	≥ 8.0 (n = 66)	1.28 ± 0.19	1.32 ± 0.30	1.22 ± 0.20	1.48 ± 0.27
		1.29 (0.95-1.85)	1.27 (0.89-2.57)	1.21 (0.78-1.73)	1.50 (0.79-2.07)
Oral contraceptives	No (n = 63)	1.24 ± 0.21	1.38 ± 0.30	1.23 ± 0.21	1.57 ± 0.32
		1.18 (0.95-1.81)	1.40 (0.97-2.57)	1.20 (0.80-1.73)	1.54 (0.79-2.67)
	Yes (n = 41)	1.20 ± 0.19	1.28 ± 0.30	1.24 ± 0.20	1.45 ± 0.25
		1.17 (0.97-1.84)	1.26 (0.81-2.13)	1.22 (0.64-1.64)	1.47 (0.83-1.98)

6C1: Convex probe; 9L4: Linear Probe; STD: Standard deviation; R: Right liver lobe; L: Left liver lobe; 50 mm/25 mm/15 mm: Depth of measurement in millimeters; BMI: Body-mass index.