Urethral bulking with polymethylmethacrylate microspheres for stress urinary XXXX : tissue persistence and safety studies in miniswine.

@entity4625 @entity1707 @entity32 @entity322 @entity4530 @entity204
OBJECTIVES: To evaluate the safety and persistence of injectable @entity4625 ( @entity4625 ) microspheres as a long-lasting urethral bulking agent in @entity1707 . @entity4625 microspheres of 2 different diameters (40 and 125  m) were tested to investigate the potential for migration and dislocation after injection. A similar product containing 40- m @entity4625 microspheres has been used as an injectable wrinkle filler for >25 years and received Food and Drug Administration approval in 2006 (ArteFill). METHODS: A total of 22 female @entity1707 received 4 submucosal implantations of @entity4625 microspheres, using either a cystoscope or a newly developed urethral injection device (UroScope). At @entity204 and necropsy at 8 days and 1, 3, and 6 months, the urethral injection site, liver, lung, spleen, and pelvic and iliac lymph nodes were processed for histologic examination and microsphere count using organ dissolution and microscopy. RESULTS: All injected @entity4530 were still present at 6 months and showed no signs of @entity32 . Tissue dissolution of the local lymph nodes and major organs demonstrated the transport of some of the 40- m microspheres to the local lymph nodes and lung but not to the liver or spleen. In contrast, no 125- m microspheres were detected in any distant organ. CONCLUSIONS: The submucosal implantation of 125- m @entity4625 microspheres into the urethra provided a safe and persistent bulking effect in @entity1707 . The positive results of the present study encourage additional investigation of 125- m @entity4625 microspheres as a long-lasting bulking agent for the treatment of female stress urinary @entity322 . Furthermore, a newly developed urethral injection device (UroScope) proved beneficial and cost-effective to facilitate the transurethral injections of 125- m @entity4625 microspheres.
