Rigi10™ Malleable Penile Prosthesis
Also Known As
Durasphere™, Durasphere® Injectable Bulking Agent, Pyrolytic Carbon-Coated Beads Bulking Agent, Carbon-Coated Zirconium Oxide Beads
Definition
Durasphere is a sterile, nonpyrogenic injectable urethral bulking agent composed of pyrolytic carbon-coated zirconium oxide beads suspended in a water-based carrier gel containing beta-glucan.1 The pyrolytic carbon-coated beads are designed to have a minimum dimension of 212 microns and a maximum dimension of 500 microns.1 The water-based carrier gel is approximately 97 percent water by volume and 3 percent beta-glucan.1 Durasphere is injected sub-mucosally at the bladder neck in females, creating increased tissue bulk and subsequent coaptation of the bladder neck.1 Over time, collagen is deposited around the pyrolytic carbon-coated beads, and the final bulking result derives from the combination of the pyrolytic carbon-coated beads and the body’s own collagen.1 The composition was designed to provide a durable, non-migratory agent of low immunogenic potential.2
Clinical Context
Durasphere is indicated for use in the treatment of adult women with stress urinary incontinence (SUI) due to intrinsic sphincter deficiency (ISD).1 It offers surgeons a long-term, less invasive support for the urethra in several clinical scenarios: when conventional surgery has not been fully effective, where the patient is not fit enough for surgery or anesthesia, where the patient would prefer not to undergo invasive surgery, or when the patient has not yet fully completed her family.3
The injection procedure involves sub-mucosal administration at the bladder neck in females.1 Clinical trials have demonstrated that Durasphere is equally effective as bovine collagen for treating SUI due to ISD, with 80.3% of women showing improvement of at least one continence grade one year after treatment.3 Long-term durability has been observed, with 73% of patients maintaining their one-year post-procedure continence grade at 4.3 years post-procedure.3
The pyrolytic carbon-coated graphite beads are not degraded by the body, so the bulking effect is maintained, and the procedure does not need to be repeated annually, unlike other bulking agents.3 However, potential complications include an increased short-term risk of urgency and urinary retention,3 and rare cases of pseudoabscess formation have been reported.2 NICE Guidelines in Urinary Incontinence suggest considering intramural bulking agents, including those of carbon-coated zirconium beads, for the management of SUI when conservative management has failed.3