This document discusses various filling defects that can occur in the ureter as seen on clinical imaging. It includes examples of nonopaque ureteral calculi, blood clots, renal vein thrombosis, transitional cell carcinoma, ureteritis cystica, ureteral tuberculosis, and malacoplakia - each presenting with different characteristic imaging patterns within the ureter. Accompanying images and descriptions help distinguish these conditions based on features like stippling, papillary contours, strictures, dilatations, beading, or thickening of the ureter.

1. 18Filling Defects in the Ureter

2. CLINICAL IMAGAGING
AN ATLAS OF DIFFERENTIAL DAIGNOSIS
EISENBERG
DR. Muhammad Bin Zulfiqar
PGR-FCPS III SIMS/SHL

3. • Fig GU 18-1 Nonopaque ureteral calculus
(arrows).

4. • Fig GU 18-2 Blood clot in a proximal ureter
(arrows).

5. • Fig GU 18-3 Renal vein thrombosis. (A) Excretory
urogram shows characteristic notching (arrow) of
the upper ureter. There is enlargement of the left
kidney with poor calyceal function due to
compression from parenchymal engorgement. (B)
In another patient with renal vein thrombosis and
ureteral notching, a venogram demonstrates
exuberant periureteral collaterals (arrows).16

6. • Fig GU 18-4 Transitional cell carcinoma of the ureter. The
presence of stippling throughout this proximal ureteral
filling defect (arrows) and the suggestive papillary contour
of its proximal and distal margins allow the correct
diagnosis to be made preoperatively.14

7. Fig GU 18-5 Transitional cell carcinoma of the midureter. Irregular
stricture with proximal ureteral and pelvocalyceal dilatation.

8. • Fig GU 18-6 Ureteritis cystica. Multiple, small,
smooth lucent filling defects in the contrast-
filled ureter and pelvis in a patient with
chronic urinary tract infection.

9. • Fig GU 18-7 Ureteral tuberculosis. (A) Segmental
areas of dilatation and constriction produce a
corkscrew, or beaded, pattern.7 (B) Thickening
and fixation of the ureter (pipe stem ureter).17

10. Fig GU 18-8 Malacoplakia of the ureter. Magnified view of the
distal right ureter shows multiple filling defects simulating
ureteritis cystica.18