Extrinsic displacement of the ureter

Intravenous Urography: Technique and Interpretation

“…Aberrant papilla in a patient with a history of transitional cell carcinoma. Medial deviation of the ureter should be considered when the ureter overlies the ipsilateral lumbar pedicle (25,36,37). Oblique image helps confirm this urographic finding.…”

“…Persistence of a standing column of contrast material on several images may indicate obstruction (Fig 35) or ureteral ileus (nonobstructive Figure 31. At about the L3 level, the ureter passes ventral to the muscle, crossing from lateral to medial (36). Tomography performed with compression for collecting system distention showed a filling defect in the middle infundibulum, suggesting an aberrant papilla.…”

Ureteral Displacement due to Congenital Psoas Muscle Hypertrophy

“…Enlarged lymph nodes, pyelectasis, abdominal aortic aneurysm, retroperitoneal tumors or fluid collections arising medial to the ureter, and central pelvic tumors such as uterine fibroid may cause lateral displacement of the ureter [1,4], Lateral deviation may occur due to psoas muscle hypertrophy at the level of L3-L5. In this case it is at the L4-L5 level.…”

“…Normally, the ureters course downwards parallel to the midline on the anterior surface of the psoas muscle and pass on to the ventral aspect of this muscle at the level of approximately L3 [3,4], This intimate relation ship of the two structures will certainly explain course deviations of the ureter, and either medial or more fre quently lateral deviation of the ureter may occur if there is psoas muscle hypertrophy [1,4].…”

“…In this case it is at the L4-L5 level. Although this benign entity can be recognized on the excretory urogram alone, eval uation by computed tomography is usually necessary [2,4], …”