Edward H. Davidson

Fat grafting accelerates revascularisation and decreases fibrosis following thermal injury

BACKGROUND Fat grafting has been shown clinically to improve the quality of burn scars. To date, no study has explored the mechanism of this effect. We aimed to do so by combining our murine model of fat grafting with a previously described murine model of thermal injury. METHODS Wild-type FVB mice (n=20) were anaesthetised, shaved and depilitated. Brass rods were heated to 100°C in a hot water bath before being applied to the dorsum of the mice for 10s, yielding a full-thickness injury. Following a 2-week recovery period, the mice underwent Doppler scanning before being fat/sham grafted with 1.5cc of human fat/saline. Half were sacrificed 4 weeks following grafting, and half were sacrificed 8 weeks following grafting. Both groups underwent repeat Doppler scanning immediately prior to sacrifice. Burn scar samples were taken following sacrifice at both time points for protein quantification, CD31 staining and Picrosirius red staining. RESULTS Doppler scanning demonstrated significantly greater flux in fat-grafted animals than saline-grafted animals at 4 weeks (fat=305±15.77mV, saline=242±15.83mV; p=0.026). Enzyme-linked immunosorbent assay (ELISA) analysis in fat-grafted animals demonstrated significant increase in vasculogenic proteins at 4 weeks (vascular endothelial growth factor (VEGF): fat=74.3±4.39ngml(-1), saline=34.3±5.23ngml(-1); p=0.004) (stromal cell-derived factor-1 (SDF-1): fat=51.8±1.23ngml(-1), saline grafted=10.2±3.22ngml(-1); p<0.001) and significant decreases in fibrotic markers at 8 weeks (transforming growth factor-ß1(TGF-ß): saline=9.30±0.93, fat=4.63±0.38ngml(-1); p=0.002) (matrix metallopeptidase 9 (MMP9): saline=13.05±1.21ngml(-1), fat=6.83±1.39ngml(-1); p=0.010). CD31 staining demonstrated significantly up-regulated vascularity at 4 weeks in fat-grafted animals (fat=30.8±3.39 vessels per high power field (hpf), saline=20.0±0.91 vessels per high power field (hpf); p=0.029). Sirius red staining demonstrated significantly reduced scar index in fat-grafted animals at 8 weeks (fat=0.69±0.10, saline=2.03±0.53; p=0.046). CONCLUSIONS Fat grafting resulted in more rapid revascularisation at the burn site as measured by laser Doppler flow, CD31 staining and chemical markers of angiogenesis. In turn, this resulted in decreased fibrosis as measured by Sirius red staining and chemical markers.

Obesity impairs wound closure through a vasculogenic mechanism

Since obesity impairs wound healing and bone marrow (BM)‐derived vasculogenic progenitor cells (PCs) are important for tissue repair, we hypothesize that obesity‐impaired wound healing is due, in part, to impaired PC mobilization, trafficking, and function. Peripheral blood was obtained from nondiabetic, obese (BMI > 30, n = 25), and nonobese (BMI < 30, n = 17) subjects. Peripheral blood human (h)PCs were isolated, quantified, and functionally assessed. To corroborate the human experiments, 6‐mm stented wounds were created on nondiabetic obese mice (TALLYHO/JngJ, n = 15) and nonobese mice (SWR/J, n = 15). Peripheral blood mouse (m)PCs were quantified and wounds were analyzed. There was no difference in the number of baseline circulating hPCs in nondiabetic, obese (hPC‐ob), and nonobese (hPC‐nl) subjects, but hPC‐ob had impaired adhesion (p < 0.05), migration (p < 0.01), and proliferation (p < 0.001). Nondiabetic obese mice had a significant decrease in the number of circulating PCs (mPC‐ob) at 7 (p = 0.008) and 14 days (p = 0.003) after wounding. The impaired circulating mPC‐ob response correlated with significantly impaired wound closure at days 14 (p < 0.001) and 21 (p < 0.001) as well as significantly fewer new blood vessels in the wounds (p < 0.001). Our results suggest that obesity impairs the BM‐derived vasculogenic PC response to peripheral injury and this, in turn, impairs wound closure.

A preliminary three-dimensional analysis of nasal aesthetics following le fort i advancement in patients with cleft lip and palate

AbstractNasal aesthetic changes after cleft orthognathic surgery remain understudied. Previous scarring associated with prior cleft surgery may affect the predictability of outcomes after jaw surgery. This study evaluates changes in nasal aesthetics using three-dimensional photography after Le Fort I advancement in patients with nonsyndromic cleft-related maxillary hypoplasia.Cephalometric parameters were recorded pre- and postoperatively. Three-dimensional photogrammetric imaging analyzed changes in interalar width (IAW), internostril width (INW), nasal tip projection (NTP), collumelar length (CL), nasal labial angle (NLA), and nasal length (NL). Statistical significance between pre- and postoperative data was determined using T-tests for each parameter.Eleven patients underwent either single piece Le Fort I osteotomy and advancement, (3 bilateral, 4 unilateral cleft lip, and palate), or 2-piece advancement (2 bilateral, 2 unilateral). Average nasal soft tissue changes were IAW 1.9 mm (0.4–4.2), INW −0.2 mm (−2.8 to 1.6), NTP −1.0 mm (−4.0 to 2.0), CL −0.7 mm (−2.9 to 1.5), NLA −0.2° (−13.9 to 15.1), and NL −0.7 mm (−4.3 to 1.5), (P = 0.001, 0.6, 0.08, 0.01, 0.9, 0.2). For single-piece osteotomy alone changes were IAW 2.1 mm (0.6–4.1), INW −0.6 mm (−2.8 to 1.7), NTP −1.9 mm (−4.0 to 0.3), CL −1.2 mm (−2.9 to 0.03), NLA −1.3° (−13.9 to 15.0), and NL −1.1 mm (−4.3 to 0.7), (P = 0.007, 0.3, 0.009, 0.0002, 0.7, 0.2). For 2-piece osteotomy alone changes were IAW 1.6 mm (−0.4 to 3.3), INW 0.5 mm (0.4–1.6), NTP 0.5 mm (−1.1–2.0), CL 0.2 mm (−1.4 to 1.5), NLA 2.8° (−7.6 to 10.1), and NL −0.1 mm (−1.4 to 1.5), (P = 0.2, 0.4, 0.5, 0.6, 0.5, 0.9).Cleft-related scarring and malposition affect changes in nasal aesthetics following maxillary advancement that are different to the noncleft population. Two-piece Le Fort I increases variability of changes in nasal aesthetics compared with single-piece advancement.

A National Curriculum of Fundamental Skills for Plastic Surgery Residency: Report of the Inaugural ACAPS Boot Camp.

Background The Inaugural American Council of Academic Plastic Surgeons Plastic Surgery Boot Camp program was developed in response to ongoing changes in graduate medical education. The Boot Camp is a hands-on, practicum-based, 3-day course to introduce core concepts in plastic surgery for new plastic surgery residents (in both integrated and independent tracks). Methods The course was held in Pittsburgh in July to August 2015. There were 43 attendees (35 integrated/8 independent) representing 22 residency programs across 15 states. Faculty was composed of 8 local personnel and 5 visiting. Lecture topics and practical sessions covered the full spectrum of plastic surgery. All trainees completed an online survey evaluation both during the course and at 6 months. Results Participant responses were overwhelmingly positive. A total of 72% of respondents rated the Boot Camp ≥ 8 on a 1 to 10 scale (10 is excellent) for the overall course rating; 79% of respondents agreed or strongly agreed with the statement that the simulation scenarios were realistic; and 75% of participants agreed or strongly agreed with the statement that they found simulation-based training to be a valuable way to teach this material. Respondents reported an increase in comfort and confidence across topics after attending the Boot Camp at both 0- and 6-month time points. Instructors received positive evaluations across all topics. Conclusions This successful inaugural course serves as a benchmark for development of a logistical blueprint, business plan, and curriculum for a proposed expansion to regional centers, to potentially encompass all incoming residents in plastic surgery.

Assessing Risk and Avoiding Complications in Breast Reduction

Assessing risk and avoiding complications in breast reduction requires a meticulous history, systematic physical examination, management of expectations, and careful consideration and execution of operative technique. Attention should be paid to comorbidities. Shape, symmetry, contours, scar location, skin quality, nipple-areolar complex (NAC) shape, NAC position relative to inframammary fold, and NAC position relative to the volume of the breast should be evaluated. Because complications cannot always be anticipated, informed consent is a vital part of managing expectations. Intraoperative considerations include blood pressure control, limiting tension, delayed healing and tissue loss, and using applied anatomy to avoid malposition and asymmetry.

Severe pediatric midface trauma: a prospective study of growth and development

AbstractSevere pediatric facial trauma is characterized by multiple, comminuted, and unstable fractures, frequently necessitating operative intervention. Disruption of facial growth is a primary concern in the long-term sequelae of such conditions. Children suffering from midface fractures were followed over time in a long-term growth and development study. Lateral cephalograms at longest-term follow-up were traced, digitized, and averaged. Seven landmarks of the midface (A point, ANS, orbitale, bridge of nose, distal U6, upper lip, stomion superius) were identified for comparative measurements with age and sex-matched superimposed Bolton norms as controls. Differences in x and y axes between test and control metrics were measured. Clinical significance was defined as a 2-mm discrepancy from the norm. Statistical significance for each patient was determined using t tests of the x and y arrays of patient values versus normal controls. Seven patients met the inclusion criteria with mean age of 8.9 years at the time of injury. Mean cephalometric follow-up was 4.6 years (range 2–10 years). Six out of 7 patients (86%) showed clinically significant impairment in growth in horizontal (29%), vertical (29%), or both planes (29%). T Tests confirmed statistical significance (P ⩽ 0.05) for all clinically significant differences. Mean deficiency in growth for all landmarks was 3.7 mm (range −4.0 to 13.7 mm) in the x axis and 2.9 mm (range −1.1 to 8.8 mm) in the y axis. Severe pediatric midface trauma often results in compromised bone growth and permanent facial deformity. New methodologies of management that better allow for growth are needed.

Mapping the Mandibular Lingula in Pierre Robin Sequence: A Guide to the Inverted-L Osteotomy.

Background and purpose: The inverted-L osteotomy for mandibular distraction in Pierre Robin sequence (PRS) is a useful technique for avoiding injury to the tooth root and inferior alveolar nerve. Identification of the lingula is understudied and may decrease iatrogenic complications. This study aims to map the position of the lingula in the micrognathic mandible and compare the location of the lingula in relative normal mandible. Methods: This is a retrospective cohort study of symptomatic PRS patients. Three-dimensional CT scans were reviewed and the relative lingula position described. Results: The study includes 11 PRS patients and 4 controls. The average measurements were overjet 9.99 (PRS) versus 4.28 mm (control) (P = 0.001), vertical ramus height 16.05 versus 23.04 mm (P = 0.003), and width 15.16 versus 20.67 mm (P = 003); horizontal ramus length 26.58 versus 40.62 mm (P = 0.001), gonial angle 132.64° versus 123.5° (P = 0.018); horizontal lingula position 7.25 versus 10.75 mm (P = 0.001), vertical position 9.02 versus 11.34 mm (P = 0.026). The ratio along the x-axis in PRS was 0.44 versus 0.52 in controls (P = 0.138); along the y-axis, the ratio was 0.57 versus 0.49 (P = 0.078). Conclusions: Compared to normal controls, overjet is greater, vertical ramus height and widths are lesser, horizontal ramus length is lesser, and the gonial angle is greater in PRS patients. When analyzed as proportions along the height and width of the vertical ramus, there is no statistical difference (P > 0.05) in the position of the lingula between PRS patients and normal controls.

Commentary on: An Innovative Procedure for the Treatment of Primary and Recurrent Capsular Contracture (CC) Following Breast Augmentation

The mechanism and management of periprosthetic capsular contracture (CC) following breast augmentation have been the subject of debate for more than half a century, and Costagliola et al,1 authors of “An Innovative Procedure for the Treatment of Primary and Recurrent Capsular Contracture (CC) Following Breast Augmentation,” have continued the discussion. The surgical implantation of a prosthesis in every patient incites an inflammatory response that results in a well-ordered process of cellular events culminating in the deposition of collagen around the prosthesis. This can be viewed as the bodys attempt to exclude the prosthesis from the immune system. It consists of the laminar deposition of a collagen envelope around the prosthesis. The cellular makeup of this envelope influences the degree of “constriction” around the prosthesis and, in the case of a breast implant, the softness or firmness of the overlying tissue. Inflammation is the initial stimulus for this process. Ongoing inflammation has been posited as the primary mechanism for continued cellular activity within the periprosthetic capsule. The 2 main hypotheses for the factors involved in the production of CC are a “hypertrophic scar induction” and continued inflammation based on a “subclinical infection.” There has been much focus during the past decade on addressing the latter for its potential as an inciting stimulus. Specific attention has been given to identifying bacterial organisms cultured from periprosthetic capsular fluid and formulating antibiotic irrigation solutions2 effective in suppressing or eliminating these bacteria in the periprosthetic capsular space. Data on the efficacy of this approach remain forthcoming. Most recently, the science of biofilms and their role in the process of bacteria-induced inflammation has been highlighted as an area for study.3 The hypertrophic scar hypothesis has many proponents, and authors have tried approaches for modulating the inflammatory stimulus thought to be an important inducing …

2564: Total human eye allotransplantation (THEA): Protocol optimization of imaging modalities in a non-human primate model

2564: Total human eye allotransplantation (THEA): Protocol optimization of imaging modalities in a non-human primate model Edward H. Davidson, MA, (Cantab), MBBS, Jonathan Carney, Brian Lopresti, Maxine Reedy Miller, MD, and Kia M. Washington University of Pittsburgh, Pittsburgh, PA, USA Background To pioneer vascularized composite allotransplantation (VCA) of the human eye as a clinical reality, our group has developed the first orthotopic model for eye transplantation in the rat for testing of immunomodulation and neuroregeneration therapies. We have also performed human cadaveric studies to design surgical protocols for donor and recipient procedures ahead of advancing to a non-human primate surgical model of eye transplantation Non-invasive methodologies of graft monitoring are paramount to development of this model as well as for clinical practice in future transplantation programs.

Commentary on: Nipple-Sparing Mastectomy Through an Inframammary Fold Incision with Implant-Based Reconstruction in Patients with Prior Cosmetic Breast Surgery.

Nipple-sparing mastectomy (NSM), as the latest evolution of mastectomy technique, has proven to result in improved reconstructive and aesthetic outcomes in breast cancer care.1 Moreover, the oncologic safety of this approach in selected patients is now well-established.2 The procedure may be performed through a radial, transverse areolar, lateral, inferolateral, double concentric periareolar, vertical infraareolar, or inframammary incision . This procedure affords the possibility for immediate autologous reconstruction, reconstruction with a tissue expander and subsequent expander implant exchange, or the direct-to-implant method. Patient and technical risk factors that increase risk of complications, namely skin and nipple-areola complex ischemia and necrosis, have been described. Smoking, body mass index, breast size, and preoperative radiation are predictors of complications.1,3-8 An increased rate of nipple necrosis is associated with the periareolar/circumareolar and trans-areolar incision patterns compared with radial or inframammary approaches.1,3,9,10 A higher incidence of nipple necrosis is seen when the selected implant with its larger volume is placed at the time of mastectomy as opposed to the more conservative two-stage tissue expander-based reconstruction strategies.1,3,4 Reconstruction with autologous tissue rather than implant-based strategies may also confer protection from ischemic complications in terms of reconstruction failure.11 Prior breast surgery, with resultant scaring and disruption of native blood supply, has a clear potential to affect the complication profile of nipple-sparing mastectomy procedures and increase the risk of skin and nipple area complex ischemia and necrosis. Nipple-sparing results in a nipple-areola complex and skin envelope that is largely dependent on the sub-dermal plexus for vascularity, given that intercostal and internal mammary perforators are often likely to be disrupted.12 Augmentation …