Reflux and trapping.
Although functional ureteral obstruction results in a decrease in the rate of antegrade urine flow, urine may still traverse the obstructed segment in a retrograde direction. Decreased musculature is found in the obstructing area. The combination of these processes results in reflux with trapping. This process has been demonstrated radiographically at both the ureterovesical and the ureteropelvic junctions.
D002675:Child, Preschool; D005260:Female; D006801:Humans; D008297:Male; D011859:Radiography; D014517:Ureteral Obstruction / Q000150:complications / Q000000981:diagnostic imaging*; D014718:Vesico-Ureteral Reflux / Q000000981:diagnostic imaging* / Q000209:etiology