ª Springer Science+Business Media New York 2015

Abdominal Imaging

Abdom Imaging (2015) DOI: 10.1007/s00261-015-0375-2

The drooping lily sign Amie M. McPherson, Raymond B. Dyer Department of Radiology, Wake Forest Baptist Medical Center, Wake Forest University School of Medicine, Medical Center Blvd., Winston-Salem, NC 27157, USA

The ‘‘drooping lily’’ (Fig. 1) has been used as a metaphor for the urographic appearance of the opacified, functioning lower pole moiety in a completely duplicated collecting system. The mass effect of the dilated and often non-opacified upper collecting system elements displaces the lower pole collecting system inferolaterally (Fig. 2), producing the appearance of the fading flower [1, 2]. In addition, the dilated upper moiety ureter may impress upon and displace the lower moiety ureter along its course. Due to the inferior and medial insertion predicted by the Weigert–Meyer rule [1], a ureterocele is often associated with the ectopic insertion of the upper moiety ureter, which may be seen as a filling defect in the bladder.

Fig. 2. Excretory urogram showing a classic ‘‘drooping lily’’ appearance in the opacified lower collecting system (curved white arrow) on the left and a filling defect in the bladder consistent with a ureterocele due to the obstructed upper pole ureter (solid white arrow). Note the incomplete ureteral duplication on the right.

Fig. 1.

A drooping lily.

Correspondence to: Amie M. McPherson; email: amcphers@wakehealth. edu

A good rule of thumb is to consider the presence of an obstructed, upper pole duplicated system any time a cystic structure is seen in the upper pole of the kidney. The obstructed upper moiety and its draining ureter may also be recognized on ultrasound (Fig. 3), CT (Fig. 4) [3], or MR imaging.

A. M. McPherson, R. B. Dyer: The drooping lily sign

Fig. 3. A Longitudinal ultrasound image of the left kidney in the patient pictured in Fig. 1 shows the dilated upper pole moiety with associated parenchymal thinning. B Hydroureter of the nonfunctional obstructed upper pole moiety is also evident.

Fig. 4. A Coronal CT urogram with MIP reformatted image shows the dilated, unopacified upper moiety of the duplicated left collecting system. The lower pole moiety is opacified with contrast material. B CT urogram 3D reformatted image shows

the asymmetric collecting system appearance. C This coronal MIP image shows the ureterocele in the bladder due to the ectopic insertion of the upper pole ureter (solid black arrow).

References

3. Cronan JJ, Amis ES, Zeman RK, Dorfman GS (1986) Obstruction of the upper-pole moiety in renal duplication in adults: CT evaluation. Radiology 161:17–21

1. Callahan MJ (2001) The drooping lily sign. Radiology 219:226–228 2. Fernbach SK, Feinstein KA, Spencer K, Lindstrom CA (1997) Ureteral duplication and its complications. RadioGraphics 17:109–127