Structural fat grafting / fat transfer is a procedure in which small amounts (less than 0.1 cc at a time) of fat are carefully introduced in a series of discrete layers to gradually 'build' new soft tissue structure. As there is space between each micrograft, new blood vessels are able to grow into the grafted fat, allowing it to persist indefinitely. If this process of blood vessel ingrowth (neovascularization) does not occur, then the transferred fat cannot truly be considered a 'graft' and is instead just another temporary 'soft tissue filler' that is broken down and reabsorbed over several weeks. Fat grafting requires specialized training and specialized surgical instruments, as well as patience and meticulous attention to detail on the part of the surgeon. When performed properly, permanent and natural-appearing aesthetic enhancements can be achieved.
For transferred fat to truly qualify as a 'graft' the following must happen: living tissue must be transferred to a new location, and that tissue must gain a blood supply at the new location which provides oxygen and nutrients which allow it to persist indefinitely as living tissue. We know that with appropriate instrumentation and technique this is achievable, so one of the opinions expressed in this thread that "most of the cells from fat injection are dead " is simply untrue (and structural fat grafting, to be clear, does not involve 'injection' of fat). MRI studies have shown that with appropriate technique grafted fat persists long-term as living, vascularized tissue in the recipient site.
It is also well-established that adult human fatty tissue contains stem cells that have the capacity to repair damaged or injured tissues, and stem cells can be concentrated during the fat harvesting process. This effect has applications in both cosmetic and reconstructive surgery. Fat grafting is now being used, for example, as a means to stimulate the repair of chronic, non-healing wounds. Several centers have reported on fat grafting immediately below non-healing chronic wounds resulting from radiation therapy for cancer, with rapid improvement and eventual healing of wounds for which no other wound treatment was successful. The development of stem cell therapies involving the harvesting and processing of viable human fatty tissue is one of the hottest topics in both clinical and experimental medicine today.
When performed correctly fat grafting actually has the capacity to heal, revitalize and rejuvenate the local tissues at the recipient site. I have treated a number of patients with facial fat atrophy following overly aggressive 'non-invasive' rejuvenation treatments including Thermage, Fraxel and IPL. Most of these patients report not only an aesthetically pleasing and permanent improvement in facial soft tissue volume, but also an improvement in the quality and vitality of their facial skin.
