Table 2.

Comparison of ARFI velocities (m/sec) for normal kidneys and hydronephrotic kidneys

ARFI velocities (m/sec)					P-value
Normal kidneys (n=61) 1.75 (0.96-2.59)	Kidneys with hydronephrosis (n=37) 1.94 (0.69-2.72)				0.079a)
	Low grade (n=15) 1.92 (0.69-2.51)		High grade (n=22) 2.02 (1.22-2.72)		0.086b)
	Grade 1 (n=13) 1.94 (0.69-2.51)	Grade 2 (n=2) 1.64 (1.48-1.80)	Grade 3 (n=4) 1.76 (1.64-2.03)	Grade 4 (n=18) 2.09 (1.22-2.72)	0.157b)

Values are presented as median (range).

ARFI, acoustic radiation force impulse.

^a)From Mann-Whitney U test.

^b)From Kruskal-Wallis test.