A bioabsorbable self-expandable, self-reinforced poly-L-lactic acid urethral stent for recurrent urethral strictures: long-term results

Abstract

Background and purpose: Biodegradable urethral stents have been used clinically for some years mainly in order to prevent postoperative urinary retention after minimally invasive thermotreatment of benign prostatic hyperplasia. We previously reported a 15-month-follow-up pilot study of a bioabsorbable self-expandable, self-reinforced poly-L-lactic acid (SR-PLLA) urethral stent in combination with optical urethrotomy in the treatment of recurrent urethral strictures. The present aim was to evaluate the long-term results of this new treatment modality.

Patients and methods: A series of 22 patients with severe urethral strictures (mean number of earlier urethrotomies 2.5) were involved. An SR-PLLA spiral stent with a bioabsorption time of 10 to 12 months was inserted into the urethra at the stricture site immediately after optical urethrotomy. Uroflowmetry, measurement of postvoiding residual urine, urine culture, and urethroscopy were performed preoperatively and at 1 and 3 months and then every 3 months up to 12 months, with subsequent follow-up visits every 6 months. The mean follow-up was 46 months.

Results: The treatment was successful in 8 of the 22 patients (36%). Six recurrences were found within the stented area and 15 outside. Patients with failure have since been treated with several urethrotomies and repeat self-dilatations or free skin urethroplasties.

Conclusions: The results of the use of a bioabsorbable SR-PLLA urethral stent for the treatment of recurrent strictures were encouraging. Without this additional therapy, the recurrence rate of strictures might have been much higher. The main problem was sudden collapse of the stent, possibly induced by outer compression. A new generation of bioabsorbable stents is already under development.