The “maiden waist” sign of the ureters

Excerpt

The fibrotic plaque associated with retroperitoneal fibrosis (RPF) is usually centered at the lumbosacral junction, often surrounding the abdominal aorta, inferior vena cava, and iliac vessels at this level [1]. The fibrotic process can also involve the ureters, where they may be drawn medially, resulting in an alteration of the normal ureteral course. When both ureters are involved, the more medial position of the opacified mid to lower ureters as seen on excretory urography (EXU), as well as CT or MR urography (Fig. 1), is said to ascribe the “figure” of a narrow-waisted maiden (Fig. 2) [2]. In addition to medial deviation, the fibrotic plaque may produce tapered narrowing of the lumen of one or both ureters in the lower lumbar or upper sacral region. The ureteral narrowing is associated with a variable degree of unilateral or bilateral hydroureteronephrosis, often with delayed excretion of contrast material (Fig. 3a, b) [3].

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