Correction of vesico-ureteric reflux by subureteric fibrin injection in dogs.

Abstract

To study the histological and radiological potential of the biomaterial fibrin in the treatment of vesico-ureteric reflux by a subureteric injection. For histological studies the bladders of 22 non-refluxing adult female dogs were exposed and in 20 of these two-component fibrin glue was injected into the right subureteric intramuscular portion of the bladder and teflon was injected into the lamina propria of the left ureter; two of them acted as controls. Two dogs were killed on alternate days over the course of 21 post-operative days and the bladders and distal portions of the ureters were examined histologically. For radiological studies micturating cystograms were obtained from 15 female puppies. In only eight puppies was vesico-ureteric reflux naturally present. In six of these two-component fibrin was injected into the right and teflon into the left subureteric areas, and in two puppies fibrin was injected into the subureteric areas, while the left sides acted as controls. Micturating cystograms and intravenous urograms were obtained from all puppies 3 weeks post-operatively. Histopathological studies showed persistence of increased amounts of endogenous collagen at the fibrin-injected sites; at the Teflon-injected sites a mass surrounded by dense granulation tissue was seen. Radiological studies revealed complete disappearance of reflux in the study group of six fibrin and Teflon-injected puppies; in two control puppies fibrin was injected into the right subureteric area only; the left sides were left untouched to show that maturation did not play a role in abolishing the spontaneously occurring reflux. Follow-up intravenous urography showed no evidence of vesico-ureteric obstruction in the treated ureters. Fibrin has the properties of a substance inducing a controlled increase in the number of endogenous collagen fibres.