Is renal ultrasound a reliable indicator of a nonobstructed duplication anomaly?

Twelve kidneys which had a non-obstructed duplication anomaly on excretory urography were studied sonographically. Ten of the twelve kidneys had a single central renal sinus echo complex; only two kidneys had a split sinus complex typical of duplication. Sonography is not a reliable technique to identify a nonobstructed duplication anomaly.