Endoscopic Collagen Injection: Its Limits in Correcting Vesico-Ureteral Reflux in Duplicated Ureters

Abstract

The aim of this prospective study was to investigate whether it is possible, by endoscopic collagen injection, to treat vesicoureteral reflux in children with reflux into a totally duplicated ureter system. For more than 7 years a prospective study has been in progress on children with grade III or IV reflux (international grading). Injections were made through a pediatric cytoscope, submucosally beneath the refluxing ureteral orifice. 0.2-1.5 ml collagen was injected. Reflux was controlled with direct radionuclide cystography 1 month later. Injections were repeated once or twice (within 3 months from the first injection) if reflux persisted. Additional controls with direct radionuclide cystography were made 6 months and 2 and 4 years later. Up to now, 24 children (27 ureter units) with reflux to a totally duplicated ureter have been treated. After 1 month, 11 out of 24 children were free from reflux; after 6 months only 6 out of 24, after 2 years only 5 out of 23, and after 4 years only 3 out of 13 children were free from the disorder. There was no statistical difference between 1-month, 6-month, 2-year, and 4-year follow-up results. The differences among children with duplicated and single ureters at each control visit were statistically highly significant. There was no significant difference between results in grade III and IV reflux. We had to treat the reflux operatively (Cohen) in 20 of these 24 children (83%). Most of the children with reflux into a duplicated ureter system cannot be cured by endoscopic collagen injection.