Objective: To establish the safety and efficacy of the periurethral injection of silicone microimplants (Macroplastique) for the treatment of genuine stress incontinence in women.
Patients and methods: Forty women (median age 50 years, range 27-74) with genuine stress incontinence confirmed on medium-fill video-cystometry were recruited to the study. Macroplastique (3-7 mL) was injected periurethrally 1 cm distal to the bladder neck at three or four points 'around the clock' under cystoscopic control. Where possible, the urodynamic study was repeated after 3 months. Results were graded as excellent (dry, no protection), good (better, but not totally dry) or poor (no improvement).
Results: Three months after a single injection, 16 (40%) were completely dry, 13 (33%) were improved and 11 (27%) were no better. Four patients who were improved were rendered dry by a second injection. After 3 years, 16 (40%) remained completely dry, seven (18%) were improved and 17 (42%) required alternative treatment with a Stamey bladder neck suspension. Dysuria for 48 h occurred in almost all patients; two were catheterized overnight and one required a catheter for 6 weeks. A comparison of maximum voiding pressures and flow rates before and 3 months after a single injection of Macroplastique revealed no urodynamic evidence of obstructed voiding (n = 25).
Conclusion: Injectable silicone microimplants produced a good to excellent result in 73% of patients in the short-term and 58% of women maintained this response after 3 years. The injection is a day-case procedure which provides a satisfactory medium-term outcome in over half of patients with genuine stress incontinence. There are few side-effects and those patients with no improvement may go on to be treated by open surgery without complication.