Optimization of uretero-intestinal anastomosis in urinary diversion: an experimental study in dogs. II. Influence of exposure to urine on the healing of the ureter and ileum.

The influence of exposure to urine on the ureteric adventitia and the ileal mucous membrane was studied in 10 mongrel dogs. When the ureter was implanted freely into the lumen of the bladder its adventitia became the seat of granulation tissue formation. This is later covered by creeping of transitional epithelium lining the ureter, forming what is in effect a ureteral nipple. Final healing is associated with an unpredictable amount of scarring. Furthermore, it was noted that healing and creeping of the ileal mucous membrane are impeded in the presence of urine. The sum of these effects is that ureters implanted in an open sulcus of the small intestine are not covered by intestinal epithelium, they tend to form spontaneous nipples and their healing is associated with either stenosis or reflux in some 30% of cases.