A case of allograft ureteral stone successfully treated with antegrade ureteroscopic lithotripsy: use of a 3D-printed model to determine the ideal approach.

We present the case of a 46-year-old man who underwent successful antegrade ureteroscopy for lithiasis in his allograft ureter. At a scheduled follow-up 15 years after transplantation, computed tomography (CT) detected a 12-mm renal stone in the renal pelvis of the transplanted kidney. During his follow-up, gross hematuria was seen; the stone moved to the ureter, causing hydronephrosis. Ultrasound and non-contrast CT revealed hydronephrosis and a 15-mm stone in the transplanted ureter. Considering the stone size, location, and the difficulty of the access to the anastomosed ureteral orifice, percutaneous ureteroscopic approach was planned. Due to the anatomical difficulty regarding his allograft kidney, we planned to prepare a 3D image and model for selecting the best percutaneous approach. The procedure was performed and a stone-free status was acquired without complication. Under precise simulation, we performed successful antegrade ureteroscopy for lithiasis in the allograft ureter supported by 3D imaging. Use of a 3D printed model may aid in a safe and effective procedure for lithiasis in the allograft kidney and ureter.