Sonographic depiction of fetal ureters

Abstract

Aims: Classic literature states that the fetal ureter should not be visible unless dilated. Our main objective was to produce an effective, reproducible method for fetal ureter depiction during an anatomic survey. Our secondary objectives were to record the frequency of visible ureters among normal fetuses and among fetuses with mild pyelectasis and also to determine the diameter of the sonographically demonstrated ureter.

Subjects and methods: One hundred twenty consecutive fetuses undergoing a second trimester scan were enrolled in the study. Ninety-nine anatomically normal fetuses and 21 fetuses with isolated mild pyelectasis (antero-posterior renal pelvis diameter of ≥4 mm and <7 mm) were subjected to a detailed anatomical survey. One hundred twenty fetuses were analyzed bilaterally.

Results: A total of 154 (64.2%) ureters were depicted. In the first group 123 (62.1%) ureters, in the second group 31 (73.8%) ureters were depicted (p = 0.06). The diameters of the ureters ranged from 0.4  to 2.7 mm. The majority (n = 80) (52%) were visualized at both proximal and distal segments.

Conclusions: Our study demonstrates that the ureter can be demonstrated in normal fetuses and in fetuses with mild pyelectasis. Ureteral depiction is likely to be composed of normal transient passage of urine associated with peristalsis and is not always a pathological finding.

Keywords:

• Fetal pyelectasis
• fetal ultrasonography
• ureter
• urinary system dilatation
• visible ureter

Acknowledgements

The original research was presented at September 2012 ISUOG congress at Copenhagen as an electronic poster. None of the authors have any financial or personal relationships that could interfere with the original research or the writing of the manuscript.

The authors would like to thank Orhan Ziylan, Ibrahim Halil Kalelioglu and Bunyamin Karasu for their contributions.

Declaration of interest

The authors declare no conflicts of interest.