A, The commonly used autologous fat grafting procedure is achieved through subcutaneous injection, but the cannula is not thin enough to inject fat grafts into a scar to elevate the surface of the scar. B, For the nanofat technique in linear scars, the condensed nanofat is injected into the scar with 29-gauge insulin syringes to elevate the surface. C, For the nanofat combination technique in irregular and patchy scars, the fat graft is injected into the tissue under the scar, and the condensed nanofat is injected into the scar to elevate both the surface and the bottom of scar.