Skin Autografts Research Articles

Human acellular amniotic membrane is adopted to treat venous ulcers.

Venous lower limb ulcers are very common and affect ~1% of the general population. The human acellular amniotic membrane (HAAM), which is isolated from the amniotic membrane (AM) via excluding the majority of cellular components, has lower antigenicity than the AM. The aim of the present study was to evaluate the effectiveness and safety of the HAAM, adopted to treat venous ulcers (VUs) of the lower extremities. The HAMM was isolated from the AM by the Stem Cells and Tissue Engineering laboratory at the West China Hospital of Sichuan University (Chengdu, China). HAMMs were grafted onto VUs in 4 patients, with follow-up evaluations performed on the 3rd day and at the end of the 1st, 2nd and 3rd week, and 2nd, 3rd and 6th month after the HAAMs were applied. The size and depth of the VU (determined based on whether the depth of VU reaches the tibial plane), the proportion of granulation tissue (whether >50%) and the degree of secretion (measured by asessing the degree of satuation in the outer gauze) and infection (assessed qualitatively via the appearance of purulence or peripheral swelling) were assessed. Pain score was monitored at the same intervals using a visual analog scale. Complete epithelialization (healed tissue) occurred in 2 cases: The first at the end of the 3rd week and the second, at the 2nd month following HAAM induction. In one of the remaining cases, ulcer size was reduced by >60%; however the ulcer size of the remaining case only reduced by <20%. Overall, the size of ulcer in cases 1, 2, 3 and 4 decreased to 1.2×1.1 and 1.4×0.4 cm, 1.3×1.8 and 2.3×1.4, respectively, with evident decreases in ulcer depth. The proportion of granulation tissue in each case was >50%. Furthermore, purulence and secretion completely disappeared in all 4 cases. Additionally, the medical cost of HAAM treatment is substantially lower than that of AM treatment, skin autografts and biomaterial transplantation, thus alleviating the patients' financial burden. These findings suggest that HAMM was highly effective in treating VUs in patients.

Histological and mechanical evaluation of antifreeze peptide (Afp1m) cryopreserved skin grafts post transplantation in a rat model

The objective of this study was to evaluate the use of Afp1m as a cryopreservative agent for skin by examining the transplanted skin histological architecture and mechanical properties following subzero cryopreservation. Thirty four (34) rats with an average weight of 208 ± 31 g (mean ± SD), were used. Twenty four (n = 24) rats were equally divided into four groups: (i) immediate non-cryopreserved skin autografts (onto same site), (ii) immediate non-cryopreserved skin autografts (onto different sites), (iii) skin autografts cryopreserved with glycerol for 72 h and (iv) skin autografts cryopreserved with Afp1m for 72 h at −4 °C. Rounded shaped full-thickness 1.5–2.5 cm in diameter skin was excised from backs of rats for the autograft transplantation. Non-cryopreserved or cryopreserved auto skin graft were positioned onto the wound defects and stitched. Non-transplanted cryopreserved and non-cryopreserved skin strips from other ten rats (n = 10) were allowed for comparative biomechanical test. All skin grafts were subjected to histological and mechanical examinations at the end of day 21. Histological results revealed that tissue architecture especially the epidermal integrity and dermal-epidermal junction of the Afp1m cryopreserved skin grafts exhibited better histological appearance, good preservation of tissue architecture and structural integrity than glycerolized skin. However, there was no significant difference among these groups in other histological criteria. There were no significant differences among the 4 groups in skin graft mechanical properties namely maximum load. In conclusion, Afp1m were found to be able to preserve the microstructure as well as the viability and function of the skin destined for skin transplantation when was kept at −4 °C for 72 h.

Effect of skin graft thickness on scar development in a porcine burn model

Animal models provide a way to investigate scar therapies in a controlled environment. It is necessary to produce uniform, reproducible scars with high anatomic and biologic similarity to human scars to better evaluate the efficacy of treatment strategies and to develop new treatments. In this study, scar development and maturation were assessed in a porcine full-thickness burn model with immediate excision and split-thickness autograft coverage. Red Duroc pigs were treated with split-thickness autografts of varying thickness: 0.026in. (“thin”) or 0.058in. (“thick”). Additionally, the thin skin grafts were meshed and expanded at 1:1.5 or 1:4 to evaluate the role of skin expansion in scar formation. Overall, the burn-excise-autograft model resulted in thick, raised scars. Treatment with thick split-thickness skin grafts resulted in less contraction and reduced scarring as well as improved biomechanics. Thin skin autograft expansion at a 1:4 ratio tended to result in scars that contracted more with increased scar height compared to the 1:1.5 expansion ratio. All treatment groups showed Matrix Metalloproteinase 2 (MMP2) and Transforming Growth Factor β1 (TGF-β1) expression that increased over time and peaked 4 weeks after grafting. Burns treated with thick split-thickness grafts showed decreased expression of pro-inflammatory genes 1 week after grafting, including insulin-like growth factor 1 (IGF-1) and TGF-β1, compared to wounds treated with thin split-thickness grafts. Overall, the burn-excise-autograft model using split-thickness autograft meshed and expanded to 1:1.5 or 1:4, resulted in thick, raised scars similar in appearance and structure to human hypertrophic scars. This model can be used in future studies to study burn treatment outcomes and new therapies.

301 Autograft Storage Practices of ABA Verified Burn Centers

The procedures used to store and maintain autograft skin can have a critical impact on the outcome of an autograft transplant. Inadequate handling and storage can result in tissue contamination, loss of graft, and/or decreased viability of the tissue. To gain insight into the storage practices for autograft skin at burn centers, a literature review was performed but it revealed little information. The data that was available showed a lack of uniformity in storage procedures. Since there are no established guidelines for these procedures, a survey was conducted to assess current ABA verified burn centers’ methods for the storage and handling of autograft tissue. An online survey was sent to each of the 71 ABA verified burn centers. The survey consisted of 10 questions pertaining to the storage and handling of autograft skin. Of the 71 surveys, 34 surveys were completed for a response rate of 48%. Half of the burn centers who responded (17 of 34) stored autograft skin. The following are the questions with results of the survey: 1. Does your burn center store autograft skin? 17 Yes / 17 No 2. What type of medium do you store autograft skin in? 7 Cell Culture Medium / 6 Normal Saline / 4 Other 3. How long do you keep autograft skin before discarding? 2 - Five Days / 8 - Fourteen Days / 7 - Other 4. How often do you change the storage medium used to store autograft skin? 1 - Every twenty-four hours / 3 - Every seventy-two hours / 10 - Do not change the storage medium / 3 - Other 5. At what temperature do you store the autograft skin? 16 above 0 to 10 degrees Celsius / 1 other 6. Do you disinfect the autograft skin? 9 Yes / 8 No 7. Do you add antibiotics to the storage medium? 10 Yes / 7 No 8. Do you culture the autograft skin/or medium for micro-organisms? 3 Yes - with a sensitivity panel / 1 Yes - without a sensitivity panel / 13 No 9. What do you culture for? 4 Bacteria / 4 Fungi / 3 Anaerobes 10. Do you have a procedure in place for when to discard autograft skin with positive culture results? 1 Yes / 8 No / 5 Physician’s Preference. Half of the surveyed burn centers do not store autograft skin. The remaining burn centers that do store autograft skin have differing storage methods. Some of the methods for storing and handling of the tissue could affect patient safety through tissue contamination, loss of graft, and/or decreased viability of the tissue. The creation of guidelines for a more uniformed practice of storing autograft skin could be created for ABA verified burn centers. This should result in better handling and storage of autograft skin that in turn could improve patient care by reducing the likelihood of tissue contamination or loss of graft.

Fabrication and In Vitro Characterization of Electrochemically Compacted Collagen/Sulfated Xylorhamnoglycuronan Matrix for Wound Healing Applications.

Skin autografts are in great demand due to injuries and disease, but there are challenges using live tissue sources, and synthetic tissue is still in its infancy. In this study, an electrocompaction method was applied to fabricate the densely packed and highly ordered collagen/sulfated xylorhamnoglycuronan (SXRGlu) scaffold which closely mimicked the major structure and components in natural skin tissue. The fabricated electrocompacted collagen/SXRGlu matrices (ECLCU) were characterized in terms of micromorphology, mechanical property, water uptake ability and degradability. The viability, proliferation and morphology of human dermal fibroblasts (HDFs) cells on the fabricated matrices were also evaluated. The results indicated that the electrocompaction process could promote HDFs proliferation and SXRGlu could improve the water uptake ability and matrices’ stability against collagenase degradation, and support fibroblast spreading on the ECLCU matrices. Therefore, all these results suggest that the electrocompacted collagen/SXRGlu scaffold is a potential candidate as a dermal substitute with enhanced biostability and biocompatibility.

Use of bilaminar grafts as life-saving interventions for severe burns: A single-center experience

BackgroundSkin coverage remains a significant hurdle in large-sized burns. Recent advances have allowed to grow Bilaminar Cultured Skin Autografts (BCSGs) from patients’ own donor sites. The aim of this study was to report long-term outcomes in patients with large-sized burns having received BCSGs. MethodsNine patients received BCSGs from January 2010 to May 2015. Except one patient who died during hospitalization, all patients were contacted. Four agreed to partake in the study. Patients were tested with the Vancouver Scar Scale (VSS), QuickDASH questionnaire and Burn Specific Health Scale (BSHS). Incisional biopsies of BCSGs were compared with patients’ autografts. ResultsFrom nine patients, mean age was 40 years and mean TBSA was 70.3%. For the four patients included, score averaged was 2.25 on the VSS, 29.5 on QuickDASH, 36/36 for psychosocial items and 63/84 for functional abilities on the BSHS. Compared with autografts, BCSGs demonstrated better pliability VSS and functionality. Biopsies showed no evidence of malignancy or atypical changes, but areas of hyperpigmentation. ConclusionThis is the first report investigating the long-term outcome of a newly developed BCSG. BCSGs demonstrated comparable results with patients’ autografts, functional outcomes on self-reported questionnaires and excellent psychological states. Precaution given the extensive unexpected hyperpigmentation must be taken and a randomized controlled study is underway.

From skin allograft coverage to allograft–micrograft sandwich method: A retrospective review of severe burn patients who received conjunctive application of cultured epithelial autografts

A 12-year retrospective review of severe burn patients who received cultured epithelial autografts (CEA) at the Singapore General Hospital Burns Centre from January 2005 to December 2016 was carried out. During this period, two different surgical modalities were employed to manage these burn injuries. In the earlier period, following early excision of the burn wounds, exposed surfaces were covered with a combination of split thickness skin autografts (STSG) and allografts. Surfaces covered with skin allografts were subsequently debrided of the allo-epidermis in about 3 weeks later, exposing the allodermis with granulating tissues for grafting of CEA; a technique known as the Cuono’s method. In the later period, allograft–autologous micrograft sandwich technique was used to graft on the early excised burns with subsequent CEA grafting. The former and latter groups represented by STSG/C (n=10) and M/CEA (n=14) respectively, were compared in terms of clinical profiles, outcomes, allograft/CEA usage and total graft cost. No significant differences were found based on mean age and presence of inhalation burns between the two treatment methods However, percentage total body surface area (TBSA) and Revised Baux Score were significantly higher (p<0.05) in the M/CEA group compared to the STSG/C group. Differences in clinical outcomes of mortality and length of hospital stay between the 2 groups were statistically insignificant. The average area amount of skin allografts used per patient in the M/CEA group was significantly lower compared to the STSG/C method group which contributed to lower total average cost of grafts used per % TBSA in the M/CEA method group. This might be attributed to the presence of micrografts which seemed to improve stabilization of the wound bed resulting in less operating procedures and improving CEA take. To conclude, the M/CEA method introduced was able to treat more severe burn patients at lower graft costs without compromising critical clinical outcomes significantly.

Stem cells, niches and scaffolds: Applications to burns and wound care.

The importance of skin to survival, and the devastating physical and psychological consequences of scarring following reparative healing of extensive or difficult to heal human wounds, cannot be disputed. We discuss the significant challenges faced by patients and healthcare providers alike in treating these wounds. New state of the art technologies have provided remarkable insights into the role of skin stem and progenitor cells and their niches in maintaining skin homeostasis and in reparative wound healing. Based on this knowledge, we examine different approaches to repair extensive burn injury and chronic wounds, including full and split thickness skin grafts, temporising matrices and scaffolds, and composite cultured skin products. Notable developments include next generation skin substitutes to replace split thickness skin autografts and next generation gene editing coupled with cell therapies to treat genodermatoses. Further refinements are predicted with the advent of bioprinting technologies, and newly defined biomaterials and autologous cell sources that can be engineered to more accurately replicate human skin architecture, function and cosmesis. These advances will undoubtedly improve quality of life for patients with extensive burns and difficult to heal wounds.

Inhibition of TGF-β signaling promotes expansion of human epidermal keratinocytes in feeder cell co-culture.

Cultured epidermal autografts have been used worldwide since 1981 for patients with extensive third-degree burn wounds and limited skin donor sites. Despite significant progress in techniques toward improving clinical outcome of skin grafts, the long in vitro preparation time of cultured autografts has remained a major factor limiting its widespread use. Here, we show that pharmacological inhibition of TGF-β signaling promotes the expansion of human epidermal keratinocytes (HEKs) with high proliferative potential in co-cultures with both murine 3T3-J2 cells and human feeder cells, including dermal fibroblasts and preadipocytes. In contrast, TGF-β signaling inhibition does not enhance the growth of HEKs in a serum- and feeder-free condition, an alternative approach to propagate HEKs for subsequent autograft production. Our results have important implications for the use of TGF-β signaling inhibition as a viable therapeutic strategy for improving Green's methodology and for more efficient production of customized skin autografts with human feeder cells.

LB53 - One year follow-up results of phase I/II clinical trial for combined treatment of chronic wounds with dermal equivalent-assisted skin autograft

LB53 - One year follow-up results of phase I/II clinical trial for combined treatment of chronic wounds with dermal equivalent-assisted skin autograft

Free skin grafting in reconstructive surgery of burns in children

When performing reconstructive surgery in children suffering from extensive post-burn hypertrophic scars, the main problem is deficiency of donor intact skin.&#x0D; Aim. This study aimed to determine the possibility of using the expander skin balloon expansion method for obtaining free, large area split-thickness skin autografts.&#x0D; Materials and methods. A comparative analysis of treatment for 39 children with extensive post-burn hypertrophic scars was performed. In 16 children (experimental group), balloon skin expansion of a donor site for obtaining large area split-thickness skin grafts (more than 100 cm²) was performed. In 23 children (control group), the large area grafts were cut off without prior balloon skin expansion of the donor site.&#x0D; Results. In cases where it is necessary to close a wound defect over 100 cm², it is advisable to perform prior balloon skin expansion of the donor site. This technique enables attainment of an injury-resistant free implant full grafting material and also provides multiple uses of a donor site without disturbing the esthetics.

Wound management and outcome of 595 electrical burns in a major burn center

BackgroundElectrical burns are important causes of trauma worldwide. This study aims to analyze the clinical characteristics, wound management, and outcome of electric burns. MethodsThis retrospective study was performed at the Institute of Burn Research of the Third Military Medical University during 2013-2015. Data including the demographics, injury patterns, wound treatment, and outcomes were collected and analyzed. ResultsA total of 595 electrical burn patients (93.8% males) were included. The average age was 37.3 ± 14.6 y, and most patients (73.5%) were aged 19∼50 years. Most patients (67.2%) were injured in work-related circumstances. The mean total body surface area was 8.8 ± 11.8% and most wounds (63.5%) were full-thickness burns. Operation times of high-voltage burns and current burns were higher than those of low-voltage burns and arc burns, respectively. Of the 375 operated patients, 83.2% (n = 312) underwent skin autografting and 49.3% (n = 185) required skin flap coverage. Common types of skin flaps were adjacent (50.3%), random (42.2%), and pedicle (35.7%). Amputation was performed in 107 cases (18.0%) and concentrated on the hands (43.9%) and upper limbs (39.3%). The mean length of stay was 42.9 ± 46.3 d and only one death occurred (0.2%). Current burns and higher numbers of operations were major risk factors for amputation and length of stay, respectively. ConclusionsElectrical burns mainly affected adult males with occupational exposures in China. Skin autografts and various skin flaps were commonly used for electric burn wound management. More standardized and effective strategies of treatment and prevention are still needed to decrease amputation rates.

Cultured Human Epidermis Combined With Meshed Skin Autografts Accelerates Epithelialization and Granulation Tissue Formation in a Rat Model.

IntroductionAs the take rate of cultured epidermal autografts in burn wound treatment is variable, widely expanded meshed auto skin grafts are often used in combination with cultured epidermal autograft to increase the take rate and achieve definitive wound coverage. However, a long time (3–4 weeks) required to prepare a cultured epidermis sheet is a disadvantage. Allogeneic cultured epidermis can be prepared in advance and cryopreserved to be used in combination with auto meshed skin grafts for treating third-degree burns. Nevertheless, the human cultured epidermis (hCE) has not been proved to accelerate wound healing after meshed skin grafting. Here, we investigated the effect of hCE on wound healing in a rat model of meshed skin grafting.Materials and MethodsHuman cultured epidermis was prepared from human neonatal foreskin and assessed by the release of growth factors into the culture medium using enzyme-linked immunosorbent assay. Skin wounds were inflicted on male F344 rats and treated by the application of widely meshed (6:1 ratio) autogenous skin grafts with or without hCE (n = 8 rats per group). Wound area, neoepithelium length, granulation tissue formation, and neovascularization were evaluated on day 7 postgrafting.ResultsHuman cultured epidermis secreted IL-1α, Basic fibroblast growth factor, platelet-derived growth factor-AA, TGF-α, TGF-β1, and vascular endothelial growth factor in vitro. In rats, hCE accelerated wound closure (P = 0.003), neoepithelium growth (P = 0.019), and granulation tissue formation (P = 0.043), and increased the number of capillaries (P = 0.0003) and gross neovascularization area (P = 0.008) compared with the control group.ConclusionsThe application of hCE with meshed grafts promoted wound closure, possibly via secretion of growth factors critical for cell proliferation and migration, suggesting that hCE can enhance the healing effect of widely expanded skin autografts.

A Role of Bovine Cardiac Myosin-Hydrogel Polymere to Accelerate Wound Healing of Autograft Skin in Rabbits

A Role of Bovine Cardiac Myosin-Hydrogel Polymere to Accelerate Wound Healing of Autograft Skin in Rabbits

Local Burn Injury Promotes Defects in the Epidermal Lipid and Antimicrobial Peptide Barriers in Human Autograft Skin and Burn Margin

Burn injury increases the risk of morbidity and mortality by promoting severe hemodynamic shock and risk for local or systemic infection. Graft failure due to poor wound healing or infection remains a significant problem for burn subjects. The mechanisms by which local burn injury compromises the epithelial antimicrobial barrier function in the burn margin, containing the elements necessary for healing of the burn site, and in distal unburned skin, which serves as potential donor tissue, are largely unknown. The objective of this study was to establish defects in epidermal barrier function in human donor skin and burn margin, to identify potential mechanisms that may lead to graft failure and/or impaired burn wound healing. In this study, we established that epidermal lipids and respective lipid synthesis enzymes were significantly reduced in both donor skin and burn margin. We further identified diverse changes in the gene expression and protein production of several candidate skin antimicrobial peptides (AMPs) in both donor skin and burn margin. These results also parallel changes in cutaneous AMP activity against common burn wound pathogens, aberrant production of epidermal proteases known to regulate barrier permeability and AMP activity, and greater production of proinflammatory cytokines known to be induced by AMPs. These findings suggest that impaired epidermal lipid and AMP regulation could contribute to graft failure and infectious complications in subjects with burn or other traumatic injury.

Live Skin Allograft in the Management of Severe Burns

Introduction: Deep burn injuries lead to dermal damage that impairs the ability of the skin to heal and regenerate on its own. Skin autografting is considered the current gold standard of care, but lack of patient’s own donor skin may require the temporary use of skin substitutes to promote wound healing, reduce pain, and prevent infection and abnormal scarring. These alternatives include donor skin allograft, xenograft, cultured epithelial cells and biosynthetic skin substitutes. Skin allograft is the use of skin from a genetically non-identical member of the same species as the recipient. Human deceased or live donor skin allografts represent a suitable and much used temporizing option for skin cover following severe burn injury until autografting is possible or re-harvesting of donor sites becomes available. Disadvantages of its use include the limited abundance and availability of donors, possible transmission of disease, the eventual rejection by the host and its handling, storing, transporting and associated costs of provision. Methods: Between August 2010 and August 2014, five patients underwent live skin allografting without medical immunosuppresion. All patients had deep severe burns of more than 40% burn surface area. 3 skin donors were patients’ mothers while 2 were brothers. Results: Three patients had complete healing not requiring skin autografting. One patient had hyper acute rejection and another had normal rejection and underwent secondary auto grafting. Conclusion: Live skin allografting is a useful skin substitute for severely burnt patients in resource limited areasKeywords: Burns, Allograft, Immunosuppresion, Family Donor

EXPRESSION AND SIGNIFICANCE OF PEROXISOME PROLIFERATOR ACTIVATED RECEPTOR γ IN KELOID

To investigate the expression and significance of peroxisome proliferator activated receptor γ(PPAR-γ) in human keloid. Twenty-three keloid samples were harvested from the patients undergoing keloid and auto-skin grafting operation as the experimental group (keloid group), and the residual normal skin after auto-skin grafting operation was collected as the control group. The expression of PPAR-γ protein was examined by immunohistochemistry staining in both keloid and normal skin. Referring to Shimizu immunohistochemical standard, the result was graded; the positive rate of samples and the rate of positive cells were calculated. Immunohistochemistry staining showed that PPAR-γ protein was expressed in both keloid and normal skin. In keloid, it located in the pricle cell layer, and granular layer of epidermis, and the dermal vessel; the degree of dyeing was very light. However, in normal skin, it located in the base layer of epidermis, dermal vessel walls, sweat glands and sebaceous glands; the dyeing degree was deeper. Immunohistochemical staining score in the keloid group (2.65±0.78) was significantly lower than that in the control group (3.65±1.19) (t=5.030, P=0.000). The positive rate of samples in the keloid group (52.17%, 12/23) was significantly lower than that in the control group (82.61%, 19/23) (χ2=4.847, P=0.028). The rate of positive cells was 46.04%±8.61% in the keloid group, which was significantly lower than that in the control group (59.39%±11.26%) (t=5.974, P=0.000). Compared with normal skin, the expression of PPAR-γ protein in keloid is down-regulated in in human keloid, indicating that PPAR-γ may be related to the formation of keloid.

Use of Skin Allograft in Upper Extremity Deep Burns

Introduction: Surgical treatment in patients with deep upper limbs diagnosis consists of elimination of nonvital tissue and coverage of resultant wound. Coverage may be definitive or temporal. One common option of temporal coverage is skin allograft, which represents a biological barrier that promotes reepithelialization and generates a matrix to skin autograft if it is necessary. Our Burn Center uses skin allograft from National Cells, Tissue and Organs Donation and Transplant Institute. This institute is in charge of the obtention from cadavers and the processing of this tissue. Objective: General objective is to describe the type of coverage used in patients with diagnosis of upper limb deep burn. Specific objective are to evaluate adhesion time of skin allograft, the percentage of dermis incorporation, and the number of surgical interventions required to reach total coverage of burn wound. Materials and Methods: We present a descriptive and retrospective study, including 50 patients with deep upper limbs burn who required hospitalization in National Burn Center in the period between December 1, 2014 and December 1, 2015. Results: In that sample, 38 where male (76%) and 12 female (24%), with a mean age of 40 years. Thirty patients (60%) required definitive coverage with skin autograft, while in 15 cases (36%) we used skin allograft. When skin allograft was used, 5 cases registered more than 80% adhesion 3 weeks postoperatory. One of those 5 cases had a 100% adhesion with dermis incorporation and reepitelialization. Four cases had an adhesion of skin allograft between 50% and 80% at 3 weeks postoperatory, and 6 patients registered less than 50% of adhesion at 3 weeks. Three of these 6 last cases had 0% of adhesion at 3 weeks. Conclusions: Skin allograft is a frequent option to burn-wound coverage in upper limb burned areas, acting as a biological and mechanic barrier during 3 weeks in 80% of total cases. That makes local treatment easier because it may be done less frequently representing less mobility for the patient and less sanitary costs. Besides, it reduces the risk of complications of burn wound and generates an appropriate matrix to skin autograft if it is required.

Surgical treatment of nasal non-melanoma skin cancer in elderly patients using dermal substitute

Conclusions: The nose is often involved by non-melanoma skin cancer (NMSC) and the increase in the incidence of such tumors, the morbidity and treatment-related costs represent a significant burden to healthcare systems. A bioresorbable dermal substitute (Hyalomatrix®) has been used for immediate dermal coverage and nose restoration after excision of infiltrating nasal NMSCs in elderly ASA III patients. Further studies on dermal substitutes are needed to improve benefit to patients.Objective: Surgical treatment of nasal non-melanoma skin cancer (NMSC) in elderly patients.Materials and methods: Ten elderly ASA III patients with nasal defects after resection of infiltrating NMSC were reconstructed in a two-stage strategy. The surgical protocol targeted an initial wide tumor excision and apposition of a dermal induction template (Hyalomatrix®) and successive full thickness skin autograft. Results were documented by photography, visual analog scale for patient satisfaction, and Vancouver scar scale for evaluation of final graft characteristics.Results: All patients were tumor-free during the 2 years follow-up. The procedure achieved acceptable nose reshaping and graft scarring evolution. Patient satisfaction was good-to-high.

Early versus Delayed Excision and Grafting of Full-Thickness Burns in a Porcine Model: A Randomized Study.

The standard of care for full-thickness burns is tangential excision followed by skin autografting; however, the timing of excision and grafting is subject to debate. The authors compared early (2 days) versus delayed (14 days) excision and grafting in a porcine full-thickness burn model. Full-thickness burns (n = 12) were created on the backs of two anesthetized pigs and assigned randomly to no excision, tangential excision followed by skin autografting 2 days after injury, or tangential excision followed by skin autografting 14 days after injury. Digital images and full-thickness biopsy specimens were taken at 16, 21, 28, and 42 days after injury to determine percentage reepithelialization and scar depth. At day 16, all burns that were excised early were completely reepithelialized, whereas only eight of 11 nonexcised burns (72.7 percent) were reepithelialized (p = 0.02). By day 21, all burns were completely reepithelialized. Scar thickness was greatest at 42 days in nonexcised burns (7.5 ± 2.1 mm); scars were thinner after early excision than after late excision (2.2 ± 1.8 mm versus 4.0 ± 1.1 mm; p < 0.001, analysis of variance). Wounds treated with early or late tangential excision followed by skin autografting were flat and minimally contracted, whereas all nonexcised burns were red, contracted, and slightly raised. Scar contraction at 28 and 42 days was greatest in nonexcised control wounds compared with early and late excised wounds. Both early and late excision followed by autografting reduce scarring in a full-thickness porcine burn model. However, early excision (2 days after injury) reduces scar thickness to a greater extent than later (after 14 days) excision.