[A case of retrocaval ureter in childhood].

We report a case of retrocaval ureter in a 14-year-old boy with the complaint of right flank pain. Intravenous pyelography and drip infusion pyelography showed right hydronephrosis and "inverted J" shaped ureter. A retrograde pyelography with venocavography revealed a typical retrocaval ureter, but abdominal CT scan did not show the "retrocaval segment". Ureterouretero-reanastomosis was performed and hydronephrosis was markedly improved. We analyzed 20 cases of retrocaval ureter in childhood.