Long-segment ureteral replacement with expanded polytetrafluoroethylene grafts

Area of Science:

• Urology
• Biomaterials Science
• Surgical Innovation

Background:

• Traumatic ureteral loss often necessitates nephrectomy due to limitations in conventional reconstructive techniques.
• Previous attempts at alloplastic ureteral replacement have been hindered by issues like obstruction, poor biocompatibility, and graft migration.

Purpose of the Study:

• To evaluate the efficacy and safety of ringed expanded polytetrafluoroethylene (PTFE) tube grafts for ureteral replacement in a canine model.
• To assess the long-term performance and biocompatibility of PTFE grafts in ureteral substitution.

Main Methods:

• Eight female dogs underwent partial ureteral replacement using ringed PTFE tube grafts.
• An innovative involuting anastomosis technique was employed for graft-bladder securement.
• Intravenous urograms and Whitaker infusion pressure tests were utilized for functional assessment over 12 months.

Main Results:

• Excellent renal function was preserved in 75% of animals, evidenced by normal urograms and low pressures.
• One animal experienced mild hydronephrosis and elevated pressure, while another succumbed to renal rupture from anastomotic obstruction.
• Histological examination confirmed graft patency without infection or encrustation in surviving animals.

Conclusions:

• Expanded PTFE demonstrates biocompatibility and potential as a prosthetic ureteral replacement, particularly when standard surgical options are not feasible.
• The described bladder anastomosis technique effectively prevented graft migration.
• While not a primary treatment, PTFE grafts offer a salvage option for ureteral defects.