Ultrasound-guided autologous myoblast injections into the extrinsic urethral sphincter: tissue engineering for the treatment of stress urinary incontinence.

INTRODUCTION AND HYPOTHESIS: Limitations of the existing treatment methods for stress urinary incontinence (SUI) have encouraged investigation of new therapeutic approaches in the field of regenerative medicine. Enabled by tissue engineering technology safety, feasibility and efficacy of ultrasound-guided intrasphincteric autologous myoblast implantation to treat SUI presented in the accompanying video were assessed in a pilot study of 38 women.
METHODS: Following upper arm muscle biopsy, autologous myoblast suspension was injected into the extrinsic urethral sphincter under transurethral ultrasound visualization. Functional electrical stimulation (FES) was used postoperatively to possibly enhance cell integration. Objective and subjective parameters were compared at 6 weeks, 3 months, and 6 months postoperatively.
RESULTS: The tissue harvest, laboratory tissue processing, and myoblast implantation were successful in all 38 patients. No serious adverse events were reported through the course of the study. Objective and subjective measurements collected at baseline were significantly improved at 6 weeks postoperatively. Additional improvement or a plateau was observed at 3 and 6 months postoperatively, not being negatively influenced by discontinuation of FES. Of the patients, 23.7 % considered their SUI cured, and 52.6 % reported improvement at 6 months; 95 % would recommend this treatment to others.
CONCLUSIONS: Intrasphincteric ultrasound-guided autologous myoblast injection for SUI is feasible. This simple to perform and well-tolerated minimally invasive procedure safely produced promising initial results.