Sonographic depiction of fetal ureters.
OBJECTIVE
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.


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.
a Department of Obstetrics and Gynecology , Bezmialem Vakif University, Faculty of Medicine , Istanbul , Turkey .
Ayse Filiz
AF
Gokmen Karasu
b Department of Perinatology , Dr. Istanbul University, Faculty of Medicine , Istanbul , Turkey .
Atil
A
Yuksel
c Department of Obstetrics and Gynecology, Faculty of Medicine , Erciyes University , Kayseri , Turkey , and.
Mehmet Serdar
MS
Kutuk
d Department of Obstetrics and Gynecology , Suleymaniye Maternity Training and Research Hospital , Istanbul , Turkey.
Gulsah
G
Keskin Ilhan
D005260:Female; D006801:Humans; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D058536:Pyelectasis / Q000000981:diagnostic imaging; D016216:Ultrasonography, Prenatal; D014513:Ureter / Q000000981:diagnostic imaging*
Fetal pyelectasis; fetal ultrasonography; ureter; urinary system dilatation; visible ureter