The treatment of sphincter incontinence with periurethral silicone implants (macroplastique)

Patients with genuine stress urinary incontinence (GSI) refractory to conservative measures often undergo a colposuspension when the reason for urine leakage is hypermobility of the bladder neck. Patients who suffer from an insufficiency of the intramural sphincter are instead often suitable for pubovaginal sling procedures, implantation of an artificial sphincter or peri/intraurethral injection of some expansion substance. Here, we present our experience of periurethral injection of silicone microimplants (Macroplastique).

We studied 8 men and 22 women with urodynamically stable detrusor, and validated GSI on a standardized quantification test. Under direct endoscopic control Macroplastique was injected. Follow-up was performed by a questionnaire and a new standardized quantification test.

Nineteen of the 22 patients with follow-up in excess of 2 years reported a considerable amelioration and their subjective impressions were also validated by the postoperative standardized quantification test (preoperative 147 g, postoperative 9 g; p < 0.001). No side effects were reported except for mild dysuria for practically all the patients, in all cases transient. A few patients also reported a short initial sensation of incomplete bladder emptying.

Considering the difficulty in treating sphincter insufficiency, particularly iatrogenic, the results in this study appear to justify the attempt of injection therapy. It may very well be performed as an outpatient procedure and, moreover, side effects are rare. If silicone microimplants are used there is no obstacle to proceed with artificial sphincter implantation, should the patient's symptoms remain unaffected by the injection procedure.