Sonographic Differentiation From Pseudoureterocele of Ectopic Ureter and Ureterocele in Pediatric Patients

Ectopic ureter and ureterocele need an adequate treatment plan and different surgical interventions. However, some cases appear as intravesical cystic lesions on ultrasound, with ectopic ureter sometimes reported as pseudoureterocele. This study aimed to describe the sonographic imaging findings of intravesical cystic lesions to differentiate between pseudoureterocele and ureterocele.

Nineteen patients with duplex collecting system and intravesical cystic lesions that were classified into pseudoureterocele and ureterocele based on the surgical findings were included. The ultrasound findings compared between the 2 groups were as follows: intravesical lesion with/without a covered muscular layer, presence/absence of notch sign within the lesion, and dynamic change in the appearance of intravesical cystic lesions using Fisher's exact test.

The lesions in 3 patients were classified as pseudoureterocele due to ectopic ureter and the remaining 16 as ureterocele. Significant differences were observed in intravesical lesions with/without a muscular layer (pseudoureterocele versus ureterocele = 3/0 versus 3/13, P = .021) and the presence or absence of a notch sign within the vesical cystic lesion (pseudoureterocele versus ureterocele = 3/0 versus 3/13, P = .021) between the groups. Although there was a tendency for the dynamic change in the appearance of intravesical cystic lesions to be more detectable in cases with ureterocele than in pseudoureterocele, the difference was not significant (0/3 versus 11/5, P = .058).

Sonographic findings, including bladder muscular layer location and the presence of a notch sign within the cystic lesion, were useful in differentiating pseudoureterocele and ureterocele in intravesical cystic lesions in pediatric patients with a duplex collecting system.