A BIORESORBABLE URETHRAL STENT - AN EXPERIMENTAL-STUDY

The aim of the present study was to examine the suitability of biodegr adable polymers as materials for a urethral stent. A new urethral sten t made of biodegradable self-reinforced poly-L-lactide (SR-PLLA) was i mplanted in 16 male rabbits after urethrotomy. Seven stents of stainle ss steel served as controls. The dimensions of the two types of stents were identical: length 15 mm, diameter 8.2 mm. The mechanical constru ction was a helical spiral. The SR-PLLA spiral was sustained with thre e microspirals, and the whole device was coated with DL-lactide to ach ieve an active initial tissue reaction and better tissue penetration. The SR-PLLA stent showed more favourable implantation properties than the steel one. Within 6 months all PLLA stents had implanted, and the tissue reaction around the stent material was minimal. The helical spi ral of stainless steel induced a remarkable inflammatory reaction due to poor implantation properties. We suggest that biodegradable SR-PLLA is a promising material for a urethral stent to prevent re-stenosis o f urethral strictures.