Importance of the renal resistive index in children suffering from vesicoureteral reflux

Objective: in our study, we wanted to assess changes and values of the rena l resistive index (RI) in children with vesicoureteral reflux (VUR) using c olor Doppler ultrasound (CDUS) techniques. Methods: We investigated 92 kidn ey units in 46 children (mean age 6 +/- 4 years) with VUR by means of CDUS. The RI was measured at the level of the interlobar and/or arcuate arteries using a color Doppler unit Acuson 128 XP/10. The CDUS findings were correl ated with those obtained using standard renal scintigraphy. Results: Childr en with VUR grades I-III showed a RI of 0.6 +/- 0.07, whereas patients suff ering from VUR grades IV and V demonstrated a significantly increased RI of 0.77 +/- 0.07 (p < 0.0001). The correlation of the CDUS measurements with the scintigraphic findings revealed a positive correlation coefficient of r (2) = 0.61. Conclusions: CDUS seems to be a helpful, radiation-free, noninv asive, and inexpensive tool in children with VUR, demonstrating a significa nt change in the RI especially in high-grade reflux. Moreover, the RI findi ngs represent a good correlation with standard renal scintigraphy. Therefor e, CDUS with assessment of the RI allows a perfect follow-up study of affec ted children.