Effectiveness and Safety of Endoscopically-Assisted Submucosal Administration of Autologous Adipose-Derived Regenerative Cells for the Treatment of Urethral Strictures

Fat tissue obtainment. Subjects will undergo liposuction under local anesthesia. In this procedure, Ringer's solution with the anesthetic lidocaine and vasoconstrictor adrenaline infused into the adipose compartment to minimize blood loss and contamination of the tissue by peripheral blood cells. 15 minutes later a hollow blunt-tipped 3 mm cannula introduced into the subcutaneous space through small (0.5 cm) incision. The cannula attached to syringe and under gentle suction moved through the adipose compartment, mechanically disrupting the fat tissue. Aspirate volume - approximately 150-200 cc. Procedure time - 30 minutes.

ADRC isolation. Aspirated fat tissue placed into sterile vessel which inserted into Celution 800/CRS System (Cytori Therapeutics Inc) - closed system for automated and standardized extraction and concentration of ADRC. Celution 800/CRS System drains excess of fluid from fat tissue and estimate it's volume After that lipoaspirate washed extensively with equal volumes of Ringer's solution to remove blood. At the end of this process System indicates required volume of enzyme reagent (Celase®) which should be added immediately by operator. After enzyme treatment Celution 800/CRS System automatically transfers isolated ADRC into washing compartment where ADRC washed and concentrated in 5 mL suspension. Tissue processing time - approximately 60 minutes. ADRC suspension match all requirements listed in technical documentation for Celution 800/CRS System. Obtained ADRC divided into 2 portions. First portion (0.2-0.5 mL) used for counting, viability and sterility assessment. Second portion placed into sterile syringe for injection.

Urethral stricture dilation. Under direct vision HiWire® hydrophilic nitinol wire positioned through the urethra and exchanged for a stiff-bodied wire. After that S-Curve urethral dilators (Cook Medical Inc.) passed over the wire guide progressing from the smallest to the largest 24(Fr) appropriate size while maintaining the wire guide's position.

Periurethral injection of ADRC. After dilation needle for injection introduced into urethra using endoscope. Urethra punctured several times circle-wise at the region of stricture at depth of 5 mm under endoscopic vision and 0.3-0.5 mL of ADRC suspension injected submucosally each time. Total volume of solution injected depends on stricture length and technical possibilities. Minimal injected volume - 3 mL, maximal - 4.5 ml. After fat micrograft injected, urethral balloon catheter placed and removed the following day.