Segmental ureteric replacement: an animal study using a free non-pedicled graft.

An animal study has been carried out on 3 baboons to assess the feasibility of replacing a damaged segment of ureter with a free, non-pedicled, full thickness graft. A 3 cm segment was excised from the middle third of one ureter from each baboon and the free graft (buccal mucosa) fashioned into a tube and interposed between the cut ends in order to replace the excised segment. The grafts were left in situ for up to 10 weeks and their subsequent fate studied radiologically, histologically and by gross specimen examination. The results showed that in all cases perfect viability of the graft was maintained and there was no evidence of graft shrinkage or of loss of patency. In one instance a stricture developed at the mid point of the graft, but this was entirely explicable on technical grounds. Urine drainage was not impaired on account of the insertion of a muscle-free (and therefore aperistaltic) segment into the ureter.