Retrocaval ureter.

A 45-year-old man presented to our clinic for a routine examination. On questioning he reported mild right-flank discomfort. There was no evidence of urinary tract infection, and his renal function was normal. A maximum-intensity-projection image of F-18 fluorodeoxyglucose positron emission tomography/computed tomography showed an inverted J-type deformity ('fishhook') with dilatation above the mid-ureter and medial swing of the middle ureteral segment (Figure 1a, arrow). A furosemide-augmented Tc-99m mercaptoacetyltriglycine (MAG3) renal scan revealed urinary stasis in the right kidney (Figure 1b). Multidetector computed tomography demonstrated an inverted J-shaped ureter (arrow) with the medial deviation posterior to the inferior vena cava (arrowhead) at the level of L3–L4 vertebrae with varying degrees of dilatation (Figure 2a). After excision of the stenosed segment, an end-to-end ureteral anastomosis (arrow) anterior to the inferior vena cava (arrowhead) was performed (Figure 2b). Postoperative multidetector computed tomography revealed a straightened course of the ureter (Figure 2b).