Use of Concentrated Endogenous Autologous Adipose Stromal Cells in Fat Grafts for Craniofacial Trauma

Overview

Traumatic facial injuries, especially those sustained in military combat, are characterized by destruction of bone and soft tissue. While the bony structures of the face can be reconstructed, it is difficult to return the soft tissue back to its original form. Many times, fat grafting, a common cosmetic and reconstructive procedure, is used in hopes of improving the soft tissue deformity. Fat grafting is a procedure in which a person's own fat is taken from areas throughout the body, usually the thighs or abdomen, with a small liposuction tube. The fat is then transferred into the area that has lost volume or fullness. The fullness of the soft tissue area may decrease over time because the transferred fat can be reabsorbed by the body. Altering the current fat grafting procedure, slightly, could lead to less reabsorption and a lasting fullness of the soft tissue area outcome of the fat graft procedure. The investigators are conducting this research study to help us improve the surgical treatment of people who have suffered facial soft tissue loss as a result of trauma. The goal of this research study is to see how each person's fat grafts will maintain the fat over time and to measure the quality of life during a 9 month post-surgical follow-up period. The total duration of participation is approximately 11-12 months. In this study, the investigators will concentrate the fat in the fat grafting procedure to determine whether this process will maintain the fat over time. The areas treated with enhanced fat grafts will be compared with areas treated with standard of care fat grafts. At least two areas of your face will be treated with fat grafts, (standard of care fat grafts and concentrated fat grafts). This study is the second of two clinical studies at the University of Pittsburgh using each person's fat graft with concentration of fat cells in the graft to observe if there is less fat resorption compared to using fat grafts alone. Each study is using a different concentration of fat in the fat graft compared to the first clinical study.

Craniofacial injuries have serious psychosocial sequele and affect quality of life. Many individuals who suffer significant facial disfigurement from injury experience psychological distress and impairment in functioning not limited to the acute phase of injury, but over a longer term period of treatment, recovery, and adjustment. Until recently, treatment of disfiguring craniofacial injuries has been mostly limited to surgical flap procedures, microsurgical tissue transfer, and implantable prostheses. However, these methods can leave conspicuous scars on the face and the donor site, and in the case of implants can lead to complications associated with foreign materials. Autologous fat grafting with minimally invasive cannulas is a procedure that has been used for decades in common plastic surgery practice for facial aesthetic procedures. This technique is also a promising treatment for soft tissue reconstruction after craniofacial trauma because the graft harvest and injection are minimally invasive. The treatment is performed by using a small liposuction cannula to aspirate fat tissue from the donor site, and then re-injecting the fat into the recipient site with specialized injection cannulas. After harvest, and prior to injection, the fat graft is subjected to a mechanical processing step to separate the aqueous layer and concentrate the adipocytes. This often takes the form of centrifugation or filtering. The main problem with autologous fat grafting is a variable resorption of the graft volume over time. As much as 30-60% of the graft volume can diminish over time. Many variables may influence the behavior of clinical fat grafts, including harvest site, harvest technique, graft preparation, and injection technique. Concentrating the already present autologous adipose stromal cells within the fat grafts is not expected to increase subject risk levels beyond the risk levels of the application of fat grafts. We are currently approved for the application of fat grafts with concentrated autologous adipose stromal cells \[IRB#10100293\]. This proposal uses an increased concentration of adipose stromal cells compared to the above referenced study; no increase of risk to the subject is anticipated. We hypothesize that fat grafting for facial trauma, facilitated by enhancing graft quality with a higher concentration of endogenous autologous vascular adipose stromal cells in the grafted tissue, will enhance the successful restoration of tissue volume and craniofacial form. The use of a higher concentration of autologous adipose stromal cells may lead to lower fat resorption rates that may be observed in the approved IRB study \[PRO10100293\]. Additionally, we hypothesize that the clinical results using the concentrated autologous stromal vascular cells will be durable and the subject's quality of life scores will be improved compared to subjects who have had fat grafting alone using historical controls.