Randomization and blinding
SCAR
The simple randomization method was used for randomization. In this way, two scar areas were randomly named A and B in each patient, and patients were given four sealed envelopes with the letters AS, AL, BS, and BL. The first letter represents the desired area, and the second letter indicates that the procedure can be performed. If the letter S is present, the SVF injection is performed along with the fractional CO