Faculty Bibliography

BACKGROUND: Fat grafting is limited by unpredictable long-term graft retention. The authors postulate that injury to the donor-derived microvasculature during harvest and subsequent ischemia may account for this clinical variability. They examined the use of the U.S. Food and Drug Administration-approved phosphodiesterase-5 inhibitor sildenafil citrate to protect graft microvasculature and its role in revascularization and survival. METHODS: Inguinal fat of donor Tie2/LacZ mice was infiltrated with sildenafil or saline, harvested, and transplanted onto the dorsa of recipient FVB mice. Additional donor mice were perfused with intraarterial trypsin to inactivate the fat graft microvasculature before harvest and transplantation. Differences in graft revascularization, perfusion, volume of retention, and biochemical changes were assessed. RESULTS: Surviving fat grafts were characterized by exclusively donor-derived vasculature inosculating with the recipient circulation at the graft periphery. Inactivation of donor-derived microvasculature decreased early graft perfusion and led to nearly total graft loss by 8 weeks. Sildenafil attenuated vascular ischemic injury, consistent with reductions in VCAM-1 and SDF1alpha expression at 48 hours and 4-fold increases in microvasculature survival by 2 weeks over controls. Compared with controls, targeted sildenafil treatment improved early graft perfusion, doubled graft retention at 12 weeks (83 percent versus 39 percent; p < 0.05), ultimately retaining 64 percent of the original graft volume by 24 weeks (compared to 4 percent; p < 0.05) with superior histologic features. CONCLUSIONS: Fat graft vascularization is critically dependent on maintenance of the donor microvasculature. Sildenafil protects the donor microvasculature during transfer and revascularization, increasing long-term volume retention. These data demonstrate a rapidly translatable method of increasing predictability and durability of fat grafting in clinical practice.

Diabetic patients exhibit dysfunction of the normal wound healing process, leading to local ischemia by vascular occlusive disease as well as sustained increases in the proinflammatory cytokines and overproduction of reactive oxygen species (ROS). Of the many sources of ROS, the enzyme xanthine oxidase (XO) has been linked to overproduction of ROS in diabetic environment and studies have demonstrated that treatment with XO inhibitors decreases XO overactivity and XO-generated ROS. This study evaluates the role of XO in the diabetic wound and the impact of specifically inhibiting its activity on wound healing. Treatment of diabetic wounds with siXDH (xanthine dehydrogenase siRNA) decreased XDH mRNA expression by 51.6%, XO activity by 35.9%, ROS levels by 78.1%, and pathologic wound burden by 31.5%, and accelerated wound healing by 7 days (23.3%). PCR analysis demonstrated that increased XO activity in wild type wound may be due to XDH to XO conversion and/or XO phosphorylation, but not to gene transcription, whereas increased XO activity in diabetic wounds may also be from gene transcription. These results suggest that XO may be responsible for large proportion of elevated oxidative stress in the diabetic wound environment and that normalizing the metabolic activity of XO using targeted delivery of siXDH may decrease overproduction of ROS and accelerate wound healing in diabetic patients.

BACKGROUND: Practitioners who are not board-certified by the American Board of Plastic Surgery are practicing cosmetic surgery. The extent of this issue across the United States has yet to be examined in detail. METHODS: A systematic search using Google was performed to evaluate the qualifications of clinicians marketing themselves as plastic surgeons. For every U.S. state, the following searches were performed: [state] plastic surgery, [state] cosmetic surgery, and [state] aesthetic surgery. The first 50 Web sites returned for each search were visited and scrutinized using the American Society of Plastic Surgeons and American Board of Plastic Surgery Web sites. RESULTS: In total, 7500 Web sites were visited, yielding 2396 board-certified plastic surgeons (77.9 percent of all practitioners). There were 284 board-certified ear, nose, and throat surgeons, 61 (21.5 percent) of whom practice outside their scope; 106 board-certified general surgeons, 100 (94.3 percent) of whom practice outside their scope; 104 board-certified oral and maxillofacial surgery surgeons, 68 (65.4 percent) of whom practice outside their scope; 70 board-certified ophthalmologists/oculoplastic surgeons, 49 (70 percent) of whom practice outside their scope; and 74 board-certified dermatologists, 36 (48.6 percent) of whom practice outside their scope. There were also 16 internal medicine doctors, 13 obstetrics and gynecology physicians, six emergency medicine physicians, three pediatricians, two urologists, two anesthesiologists, and finally one phlebotomist; all of these practitioners practice outside their scope as defined by Accreditation Council for Graduate Medical Education core competencies. CONCLUSIONS: Many clinicians performing cosmetic surgery are not board-certified. This finding has important implications for patient safety.