Robert L. Lebowitz, M.D. Children' s Hospital, Harvard Medical School Boston, Massachusetts

Five-year-old boy with prenatal diagnosis of hydronephrosis in 1995. Evaluation after delivery showed left hydroureteronephrosis but only mild obstruction (Fig 1). No surgery was done. Follow-up IVP five years later showed almost complete spontaneous resolution of the hydroureteronephrosis (Fig 2)

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