Long-segment ureteral replacement with expanded polytetrafluoroethylene grafts

Traumatic loss of significant lengths of ureter all too often results in nephrectomy when vascularized pedicles of bowel or bladder fail or are not available for substitution. Historically, alloplastic replacement of ureters has failed due to obstruction, bioincompatibility, or graft migration. This study was undertaken to test the performance of ringed expanded polytetrafluoroethylene (PTFE) tube grafts as ureteral replacements in a canine model.

Eight female dogs underwent partial ureteral replacement with ringed PTFE tube grafts. An involuting anastomosis was used to anchor the graft to the bladder. The dogs were followed with intravenous urograms and Whitaker infusion pressure tests for up to 12 months.

Six of 8 animals (75%) had preservation of excellent renal function with normal intravenous urograms and low Whitaker infusion pressures. One animal had mild hydronephrosis with an elevated infusion pressure. One animal died of spontaneous renal rupture secondary to obstruction at the ureteral-graft anastomosis. All other grafts were patent by histologic examination without encrustation or infection.

Although not suggested as first-line therapy after ureteral loss, expanded PTFE may have a use as a prosthetic ureteral replacement in situations where conventional surgical therapies are unsuccessful. This material appears to be biocompatible, and the technique of bladder anastomosis described here prevented migration of the prosthesis.