VALUE OF DOPPLER ULTRASOUND FOR THE DIAGNOSIS OF RENAL-ARTERY STENOSIS IN CHILDREN

To evaluate the reliability of Doppler ultrasonography (US) in identif ying children with renal artery stenosis (RAS) among those with hypert ension, we compared Doppler US results in 22 hypertensive children (me an age 8.9 +/- 4.3 years), with (13 cases) and without RAS at angiogra phy, and in 33 normotensive children (mean age 8.8 +/- 4.7 years). We observed 2 false-negatives and 2 false-positives with Doppler US. Of t he 2 false-negative diagnoses, 1 had RAS on an accessory renal artery located behind a normal upper polar artery and the other was observed in a patient with bilateral multiple stenosis of the very distal segme nts of renal arteries. The 2 false-positive diagnoses were due to sinu ous left renal artery and to technical reasons, respectively. In anoth er patient, Doppler US showed a tight RAS, while arteriography was nor mal. RAS was subsequently confirmed by a second arteriography. Peak sy stolic velocity values of Doppler US were significantly higher in pati ents with proven angiographic RAS (3.44 +/- 0.66 m/s) than in hyperten sive patients with normal renal arteries at angiography (0.99 +/- 0.35 m/s, P < 0.0001) and normotensive healthy children (1.04 +/- 0.23 m/s , P < 0.0001). With the use of multiple views, and the experience acqu ired with practice, false-negatives or false-positives due to the geom etry of the renal artery can be avoided. Nevertheless, very distal ste nosis can be missed by Doppler US.