Rigi10™ Malleable Penile Prosthesis
Also Known As
Polydimethylsiloxane injection, PDMS urethral bulking agent, silicone microimplants, MPQ
Definition
Macroplastique is a permanently implanted, non-pyrogenic, injectable urethral bulking agent composed of polydimethylsiloxane (silicone elastomer) particles suspended in a polyvinylpyrrolidone (PVP) carrier gel1. This minimally invasive treatment is primarily used for stress urinary incontinence (SUI) due to intrinsic sphincter deficiency (ISD)2. The PVP carrier is water-soluble and is absorbed and removed from the body in urine, while the cross-linked polydimethylsiloxane particles remain permanently in place3. When injected into the urethral submucosa, Macroplastique creates increased tissue bulk around the urethra, resulting in greater urethral closure pressure and reduced urinary leakage during physical activities4. The large, heavily textured elastomer implants promote tissue in-growth, creating a bolus surrounded and infiltrated by host collagen that anchors it within the space between the lamina propria and the urethral muscularis5.
Clinical Context
Macroplastique is clinically indicated for transurethral injection in the treatment of adult women diagnosed with stress urinary incontinence (SUI) primarily due to intrinsic sphincter deficiency (ISD)1. Patient selection criteria typically include women with SUI who have failed conservative treatments or prefer a minimally invasive option over more extensive surgical procedures2. It is particularly suitable for elderly patients and those at higher risk for anesthetic complications3.
The procedure is performed under local anesthesia in an outpatient setting4. Prior to the procedure, patients receive antibiotics to reduce infection risk. The injection is performed under cystoscopic visualization, with Macroplastique injected into the urethral submucosa approximately 1.5 to 2 cm distal to the bladder neck until urethral coaptation is achieved5. The procedure typically takes less than 30 minutes, with most patients able to return home the same day.
Clinical studies have demonstrated improvement rates of 75% in the short-term (<6 months), 73% in the mid-term (6-18 months), and 64% in the long-term (>18 months)1. Complete cure or dryness rates were reported as 43%, 37%, and 36% over the same respective follow-up periods1. Some patients require reinjection for optimal results, with higher reinjection rates associated with improved long-term outcomes1. Macroplastique has been used safely and effectively in over 70,000 patients since 1991, with a low rate of side effects4.
Contraindications include acute urogenital tract inflammation or infection and fragile urethral mucosal lining (e.g., post-radiation therapy, post-surgery to the bladder neck)5.