Diagnostic value of renal resistive index for the assessment of renal colic

Kavakli HS, Koktener A, Yilmaz A
Correspondence: Dr Havva Sahin Kavakli, havvasahin1973@yahoo.com

ABSTRACT
Introduction The aim of this study was to investigate the value of renal resistive index (RI) for the assessment of renal colic and to determine whether it is predictive of renal stone disease.
Methods A total of 70 participants were included in the research study. Group 1 comprised 43 patients with acute unilateral ureteral obstruction due to a stone disease (G1), while Group 2 consisted of seven patients with flank pain without stone disease (G2) and the control group comprised 20 healthy individuals with two normal kidneys (G3). Urinalysis, abdominal plain film radiography, conventional ultrasonography (US) and colour Doppler US were performed in all three groups. RI was calculated for all patients using Doppler US. The RI values in G1 were then compared with those in G2 and the control group.
Results There were statistically significant differences in the RI between the stone-positive group and stone-free groups (0.71 +/- 0.07 for G1; 0.69 +/- 0.06 for G2; 0.62 +/- 0.03 for G3, p-value < 0.05).
Conclusion RI measurement using Doppler US can be effectively used for the assessment of renal colic patients by non-invasive means.

Keywords: Doppler ultrasound, emergency department, renal colic, resistive index, stone disease
Singapore Med J 2011; 52(4): 271-273