The Effect of Stromal Vascular Fraction Transplantation on the Regeneration of Expanded Skin

Subcutaneous fat was harvested from either the abdomen or the posterior inner thigh region and then digested with 600 U of collagenase (Shanghai Qiaoyuan Biological Pharmaceutical Co., Ltd, Shanghai, China) at 37°C and 150rpm for three hours. After enzymatic digestion, the lower aqueous phase liquid was aspirated to acquire the stromal vascular fraction (SVF). The SVF cell-pellet was washed and adjusted to 2×10\^6 cells/mL. Lidocaine cream will be applied to the expanded skin to achieve surface anesthesia. The skin was marked with methylene blue and a total of 0.5ml (around 1×10\^6 cells) were transplanted intradermally at the center of each 2cm×2cm squares. The expander was inflated two times a week using constant pressure inflation method, where the intracapsular pressure was monitored using a pressure meter and the inflation was halted when the pressure reached 100 mmHg.

Lidocaine cream will be applied to the expanded skin to achieve surface anesthesia. The skin was marked with methylene blue and a total of 0.5ml 0.9% normal saline were transplanted intradermally at the center of each 2cm×2cm squares. The expander was inflated two times a week using constant pressure inflation method, where the intracapsular pressure was monitored using a pressure meter and the inflation was halted when the pressure reached 100 mmHg.