Scintigraphic evaluation of obstructing primary megaureter with Tc-99m MAG3.

Two children with the antenatal diagnosis of hydronephrosis secondary to a primary obstructed megaureter are presented. Both children were treated nonoperatively. They were observed with serial diuretic scintigrams using Tc-99m MAG3 and renal sonography. Throughout, the children have been asymptomatic. During a 3-year follow-up period, the diuretic renogram documented resolution of obstruction in one child and stable renal function with improved drainage in the other.