title: The uretero-vesical jet as a functional diagnostic tool in childhood hydronephrosis.
abstract: Childhood hydronephrosis (HN) is accurately detected by ultrasound (US), but its functional work-up remains a domain of scintigraphy, the Whitaker-test, and clinical follow-up. We utilized color doppler US (CD-Jet) of uretero-vesical jets (UVJ) to visualize the post-obstructive ureteral flow in childhood HN. A total of 177 standardized CD-Jet were performed in 132 children aged 1 day to 14.9 years. Sixty-nine investigations in 43 patients with unilateral HN were compared with a standardized technetium 99m-mercaptotriacetylglycine nephrogram; in 10 infants both procedures were performed consecutively on the same day. UVJ were visible in 96% of all investigations. Ureteral obstruction resulted in absence of UVJ in 85% of examinations; in the remaining 15% the jet frequency was less than 10% observed in the contralateral control. Results are highly significant in both uretero-pelvic (P < 0.00007) and uretero-vesical lesions (P < 0.00005, Wilcoxon test) and are reproducible in sequential investigations. In nonobstructive distal HN the jet frequency averaged 70% of the unaffected side (P < 0.05). In proximal lesions it is equal. Jet evaluation in reflux nephropathy did not differ from controls. Compared with scintigraphy, CD-US identifies obstruction with a specificity of 94.2% and sensitivity of 94.8%. CD-US of UVJ therefore may serve as a reliable screening parameter in unilateral childhood HN.
authors.affiliation: Children's Hospital, Universitäts-Krankenhaus Hamburg-Eppendorf, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Strehlau
authors.forename: P
authors.initials: P
authors.lastname: Winkler
authors.forename: J
authors.initials: J
authors.lastname: de la Roche
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D006869:Hydronephrosis / Q000000981:diagnostic imaging*; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D011877:Radionuclide Imaging; D018615:Ultrasonography, Doppler, Color; D014718:Vesico-Ureteral Reflux / Q000000981:diagnostic imaging