Figure 6. Ureteral kink mimicking a filling defect. (a) An axial image demonstrates an apparent tiny filling defect (arrow) in the proximal left ureter. This filling defect is caused by tortuosity of the ureter associated with a ureteral kink. (b) Although the presence of the kink can be suspected by reviewing the axial images sequentially, it is more easily identified on a coronal three-dimensionally reconstructed image.