Ultrasonographic Diagnosis of Ectopic Ureter Draining into the Vagina or Vestibule

To evaluate the ultrasound diagnostic performance in female pediatric patients with ectopic-ureter insertion into the vagina/vestibule or urethra/bladder neck and to compare patient characteristics.

Of 34 patients (35 vesicoureteral junctions), ultrasonically evaluated ectopic-ureter presence and location (vagina/vestibule or urethra/bladder neck). Patients were classified into 2 groups based on surgical findings: with vagina/vestibule or urethra/bladder-neck insertion. Correct/incorrect location of ectopic-ureter insertion using ultrasound, presence/absence of nonfunctional kidneys, a duplex collecting system, and duplex vagina were compared between both groups using Fisher's exact test.

Of 35 vesicoureteral junctions, 5 could not be evaluated at the junction, 30 (85.7%) had a suspected ectopic ureter, and 26 (74.3%) had a correct location diagnosis. Of 14 with vagina/vestibule insertion, 7 (50.0%) had correctly diagnosed locations. Of 21 with urethra/bladder-neck insertion, 19 (90.5%) were correctly diagnosed using ultrasound. Of the 13 of 15 patients with nonfunctional kidneys/duplex urinary system, 9 of 1 had findings involving the vagina/vestibule, and 4 of 14 had findings involving the urethra/bladder neck. Statistically significant differences were observed in correct/incorrect ultrasound diagnosis for the location of ectopic-ureter insertions (vagina/vestibule, 7/7; urethra/bladder-neck insertions, 19/2; p = .015), nonfunctional/functional kidneys (vagina/vestibule, 9/5; urethra/bladder-neck insertions, 4/17; p = .012), and presence/absence of duplex collecting system on the ipsilateral side of the ectopic ureter (vagina/vestibule 1/13; urethra/bladder-neck insertions, 14/7; p < .001). There were no significant differences in presence/absence of duplex vagina (p = .090).

Ultrasound was useful in detecting ectopic-ureter presence. However, the diagnostic performance for determining the location of vagina/vestibule insertions was approximately 50%. Sonographers should carefully evaluate the vesicoureteral-insertion location, particularly in cases with nonfunctional kidneys.