Retrocaval ureter successfully treated with laparoscopic ureteroplasty and functionally evaluated using Tc-99 m MAG-3...

Retrocaval ureter (RCU) is a rare congenital anomaly in which the ureter passes posterior to the inferior vena cava (IVC), causing urinary obstruction. The treatment generally involves surgical ureteral reconstruction. We report a case of RCU successfully treated with laparoscopic ureteroplasty, with favorable postoperative outcomes confirmed using technetium-99 m mercaptoacetyltriglycine (Tc-99 m MAG-3) renal scintigraphy.

A 22-year-old Japanese man presented with a 3-year history of dull right flank pain. Physical examinations and basic laboratory investigations returned normal results. Abdominal ultrasound identified hydronephrosis on the right side, and computed tomography urography revealed a characteristic "S"-shaped or "fishhook"-shaped right ureter, resulting in a diagnosis of RCU Type I. The patient was treated with laparoscopic ureteroplasty. Postoperatively, the hydronephrosis has been resolved and his symptoms have improved. Tc-99 m MAG-3 renal scintigraphy after 3 years postoperatively revealed demonstrating improvement in the delayed excretion from the right ureter observed before surgery.

Surgical treatment for symptomatic RCU is effective in relieving symptoms and preventing renal function deterioration. Laparoscopic ureteroplasty offers a minimally invasive approach with favorable outcomes. Tc-99 m MAG-3 renal scintigraphy serves as a valuable tool for the functional assessment of laparoscopic ureteroplasty in the management of RCU.