Bullet and bodkin sign is the appearance of the ureter when there is an abrupt transition in the ureteral caliber. Bullet in the name is represented by the dilated proximal ureteric segment which appears to be perched on the constricted / non-dilated encased ureter which gives an appearance of a bodkin.
This appearance can be seen in:
- metastatic disease
- extension from adjacent tumor
- lymphoma
- benign inflammatory conditions like retroperitoneal fibrosis