Negative-pressure wound therapy combined with artificial dermis (Terudermis) followed by split-thickness skin graft might be an effective treatment option for wounds exposing tendon and bone: A retrospective observation study.

ABSTRACT: Skin grafts are not suitable for closing tendon- or bone-exposing wounds, which require flap surgery. Dermal regeneration templates have value for closing such wounds, but the disadvantages of the technique include implantation failures because of infection, hematoma formation, or inappropriate immobilization. Negative-pressure wound therapy was reported to increase graft acceptance in difficult wounds.This retrospective case series of 65 patients evaluated negative-pressure therapy combined with artificial dermis for the treatment of acute or chronic tendon- or bone-exposing wounds. The artificial dermis was placed after adequate wound-bed preparation, with simultaneous application of a vacuum-assisted closure system. Split-thickness skin grafting was performed after the implanted artificial dermis had become established.The overall success rate was 88.1% (59/67): 88.6% (39/44) in the chronic wounds group and 87% (20/23) in the acute-trauma group separately. The overall mean survival time of artificial dermis in success cases was 13.24 ±â€Š7.14 days. In separately, the survival time of artificial dermis had no statistically difference in chronic wound group (13.64 ±â€Š7.53 vs 12.60 ±â€Š5.86. P = .943), but had significant statistical difference in acute trauma group (12.45 ±â€Š6.44 days vs 23.33 ±â€Š4.04 days, P = .018). Also, comorbidity of PAOD was found a strong risk factor of failure in chronic wound group (100% vs 23.1%, P < 0.001).We concluded that artificial dermis combined with negative-pressure therapy followed by split-thickness skin grafting might be a reliable and effective option for surgical reconstruction of tendon- or bone-exposing wounds, and could decreasing waiting periods of autologous skin graft.

Advances in Dermoepidermal Skin Substitutes for Diabetic Foot Ulcers.

Diabetic foot ulcers (DFUs) are one of the major complications of diabetes, representing a leading cause of hospitalisation and non-traumatic lower limb amputations. Multidisciplinary management, patient education, glucose control, debridement, off-loading, infection control, and adequate perfusion are the mainstays of standard care. Despite all these, at least 30% of DFUs fail to heal within 20 weeks. Therefore, dermoepidermal skin substitutes (DSS) have been used as a new therapeutic adjunct for DFUs. This brief review outlines the recent advances in DSS for the treatment of DFUs. PubMed and Cochrane databases were systematically searched in May to July 2018 for systematic reviews published after 2013 and for randomised controlled trials (RCTs). A retrospective evaluation of 28 RCTs was performed. Rates of complete wound closure and time to healing were examined for 17 commonly available DSS. Healing rates after 12 weeks and time to complete closure in DFUs are heterogeneous among the 28 RCT. The best healing rates at 12 weeks were accomplished with dermal cellular substitutes (Epifix®, 100% and Amnioband®, 85%) and with dermal acellular substitutes (Allopatch®, 80% and Hyalograft®, 78.8%). Based on these studies, DSS used in conjunction with standard care appear to improve the healing rates of DFUs, as compared with standard care alone. Nonetheless, new studies with more homogeneous samples are needed to ascertain the role of ulcer size, duration, depth and/or type in the efficacy of DSS. Moreover, future RCTs should include patients with severe comorbidities, in order to be more representative of clinical reality.

Spray on skin for diabetic foot ulcers: an open label randomised controlled trial.

BACKGROUND: One Australian loses a limb every 3 h as a result of infected diabetic foot ulcers (DFU). This common condition accounts for substantial morbidity and mortality for affected individuals and heavy economic costs for the health sector and the community. There is an urgent need to test interventions that improve wound healing time, prevent amputations and recurrent ulceration in patients presenting with DFU whilst improving quality of life and reducing health care costs. METHODS: One hundred and fifty eligible participants will be randomised to receive an autologous skin cell suspension, also termed 'spray-on' skin (ReCell®) or standard care interventions for their DFU. The primary outcome is complete wound healing at 6 months, but participants will be followed up for a total of 12 months to enable secondary outcomes including total overall costs, ulcer free days at 12 months and quality of life to be assessed. DISCUSSION: Outpatient costs for dressings, home nursing visits and outpatient appointments are key cost drivers for DFU. If spray-on skin is effective, large cost savings to WA Health will be realised immediately through a shortened time to healing, and through a higher proportion of patients achieving complete healing. Shortened healing times may enable participants to return to work earlier. Any economic benefits are likely to be amplified across Australia and other similar demographic settings where aging populations with increased diabetes rates are considered major future challenges. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12618000511235. Registered on 9 April 2018.

Experiences with a temporary synthetic skin substitute after decompressive craniectomy: a retrospective two-center analysis.

BACKGROUND: Decompressive craniectomy is a commonly performed procedure. It reduces intracranial pressure, improves survival, and thus might have a positive impact on several neurosurgical diseases and emergencies. Sometimes primary skin closure is not possible due to cerebral herniation or extensive skin defects. In order to prevent further restriction of the underlying tissue, a temporary skin expansion might be necessary. METHODS AND MATERIAL: We retrospectively reviewed patients in need for a temporary skin substitute because skin closure was not possible after craniectomy without violating brain tissue underneath in a time period of 6 years (2011-2016). With this study, we present initial experiences of Epigard (Biovision, Germany) as an artificial temporary skin replacement. We performed this analysis at two level-1 trauma centers (Trauma Center Murnau, Germany; University Hospital of St. Poelten, Austria). Demographic data, injury and surgical characteristics, and complication rates were analyzed via chart review. We identified nine patients within our study period. Six patients suffered from severe traumatic brain injury and developed pronounced cerebral herniation in the acute or subacute phase. Three patients presented with non-traumatic conditions (one atypical intracerebral hemorrhage and two patients with extensive destructive tumors invading the skull and scalp). RESULTS: A total of 20 Epigard exchanges (range 1-4) were necessary before skin closure was possible. A CSF fistula due to a leaky Epigard at the interface to the skin was observed in two patients (22%). Additional complications were four wound infections, three CNS infections, and three patients developed a shunt dependency. Three patients died within the first month after injury. CONCLUSIONS: Temporary skin closure with Epigard as a substitute is feasible for a variety of neurosurgical conditions. The high complication and mortality rate reflect the complexity of the encountered pathologies and need to be considered when counseling the patient and their families.

An Outbreak of Severe Group A Streptococcus Infections Associated with Podiatric Application of a Biologic Dermal Substitute.

OBJECTIVE: To describe an outbreak of severe Group A Streptococcus (GAS) infections that appeared to be associated with use of a biologic dermal substitute on foot wounds DESIGN: Retrospective cohort study of cases and similar uninfected patients SETTING/PATIENTS: Patients attending the podiatry clinic at a Veterans Affairs Medical Center between July 2011 and November 2011 INTERVENTIONS: Microbiology laboratory data were reviewed for the calendar year, a case definition was established and use of the biologic dermal substitute was discontinued. Staff were cultured to identify potentially colonized employees. A case-cohort study was designed to investigate risk factors for disease. Emm typing and pulsed field gel electrophoresis (PFGE) were performed to identify strain similarity. RESULTS: In 10 months, 14 cases were identified, and 4 of these patients died. All strains were emm type 28 and were identical according to PFGE. Discontinuation of biologic dermal substitute use halted the outbreak. A prior stroke was more common in the case cohort vs uninfected patient cohorts. The number of patients attending the clinic on 13 probable transmission days was significantly higher than on nontransmission days. We identified 2 patients who were present in the clinic on all but 1 probable transmission day. Surveillance cultures of podiatry clinic staff and cultures of the same lot of retained graft material were negative. CONCLUSIONS: A carrier was not identified, and we believe the outbreak was associated with inter-patient transmission likely due to lapses in infection control techniques. No additional cases have been identified in >3 years following the resumption of dermal substitute use in May 2012.

Keratinocytes in the treatment of severe burn injury: an update.

Burns are among the most life-threatening physical injuries, in which fast wound closure is crucial. The surgical burn care has evolved considerably throughout the past decennia resulting in a shift of therapeutic goals. Therapies aiming to provide coverage of the burn have been replaced by treatments that have both functional as aesthetic outcomes. The standard in treating severe burns is still early excision followed by skin grafting. The use of cultured keratinocytes to cover extensive burn wounds appeared very promising at first, but the technique still has several limitations of which the long time to culture, the major costs, the risk of infection and the need for an adequate dermal layer limit clinical application. The introduction of dermal substitutes, composite grafts, tissue engineering based on stem cell application have been advocated. The aim of this review is to assess the use of cultured keratinocytes in terms of technical aspects, clinical application, limitations and future perspectives. Cultured keratinocytes are expected to keep playing a role in wound healing, especially in the field of chronic wounds. In severe burns, despite its limitations, keratinocytes can be beneficial if implemented as one of the elements in a broader wound management.

A systematic review and meta-analysis of complications associated with acellular dermal matrix-assisted breast reconstruction.

BACKGROUND: Multiple outcome studies have been published on the use of acellular dermal matrix (ADM) in breast reconstruction with disparate results. The purpose of this study was to conduct a systematic review and meta-analysis to determine an aggregate estimate of risks associated with ADM-assisted breast reconstruction. METHODS: The MEDLINE, Web of Science, and Cochrane Library databases were queried, and relevant articles published up to September 2010 were analyzed based on specific inclusion criteria. Seven complications were studied including seroma, cellulitis, infection, hematoma, skin flap necrosis, capsular contracture, and reconstructive failure. A pooled random effects estimate for each complication and 95% confidence intervals (CI) were derived. For comparisons of ADM and non-ADM, the pooled random effects odds ratio (OR) and 95% CI were derived. Heterogeneity was measured using the I2 statistic. RESULTS: Sixteen studies met the inclusion criteria. The pooled complication rates were seroma (6.9%; 95% CI, 5.3%-8.8%), cellulitis (2.0%; 95% CI, 1.2%-3.1%), infection (5.7%; 95% CI, 4.3%-7.3%), skin flap necrosis (10.9%; 95% CI, 8.7%-13.5%), hematoma (1.3%; 95% CI, 0.6%-2.4%), capsular contracture (0.6%; 95% CI, 0.1%-1.7%), and reconstructive failure (5.1%; 95% CI, 3.8%-6.7%). Five studies reported findings for both the ADM and non-ADM patients and were used in the meta-analysis to calculate pooled OR. ADM-assisted breast reconstructions had a higher likelihood of seroma (pooled OR, 3.9; 95% CI, 2.4-6.2), infection (pooled OR, 2.7; 95% CI, 1.1-6.4), and reconstructive failure (pooled OR, 3.0; 95% CI, 1.3-6.8) than breast reconstructions without the use of ADM. The relation of ADM use to hematoma (pooled OR, 2.0; 95% CI, 0.8-5.2), cellulitis (pooled OR, 2.0; 95% CI, 0.9-4.3), and skin flap necrosis (pooled OR, 1.9; 95% CI, 0.6-5.4) was inconclusive. CONCLUSIONS: In the studies evaluated, ADM-assisted breast reconstructions exhibited a higher likelihood of seroma, infection, and reconstructive failure than prosthetic-based breast reconstructions using traditional musculofascial flaps. ADM is associated with a lower rate of capsular contracture. A careful risk/benefit analysis should be performed when choosing to use ADM in implant-based breast reconstruction.

Acellular dermal matrix masking detection of recurrent breast carcinoma: a novel complication.

Acellular dermal matrix (ADM) use in prosthetic breast reconstruction has become increasingly popular. Several benefits have been reported with this technique including diminished donor-site morbidity and improved aesthetic outcomes. Recently, in an effort to ascertain the overall safety and efficacy of this approach, an emphasis has been placed on identifying potential postoperative complications. This report describes a unique complication experienced with ADM use in which ADM conceals the detection of recurrent breast carcinoma.

Complications of alloderm and dermamatrix for parotidectomy reconstruction.

BACKGROUND: AlloDerm and DermaMatrix are 2 acellular dermal implants currently used by reconstructive surgeons at our institution for reconstruction of parotidectomy defects. We looked at the postoperative complication rates following subcutaneous implantation of these acellular dermal implants for parotid bed reconstruction. METHODS: A retrospective analysis was conducted following approval by the Institutional Review Board at Vanderbilt University Medical Center. All parotid and reconstructive operations were performed between 2001 and 2009 by 1 of 4 surgeons in the Department of Otolaryngology-Head and Neck Surgery. Data were collected to determine operative variables and postoperative course. Operative variables assessed were tumor type, type of implant used, type of parotidectomy (total or subtotal), and duration of Jackson Pratt (JP) drain placement. RESULTS: One hundred patients were analyzed. Sixty-nine AlloDerm implants were associated with 5 complications (7%), whereas 31 DermaMatrix implants were associated with 8 complications (26%) (p = .0107). When comparing total parotidectomies, the complication rate was 1 of 20 for AlloDerm (5%) and 1 of 12 for DermaMatrix (8%) (p = .7061). When looking at subtotal parotidectomies, the incidence of complications was found to be 4 of 49 for AlloDerm (8%) and 7 of 19 for DermaMatrix (37%) (p = .004). CONCLUSIONS: Our study suggests that DermaMatrix was associated with increased postoperative complications compared to AlloDerm, especially in the subset of patients undergoing subtotal parotidectomy.

The evidence for the use of growth factors and active skin substitutes for the treatment of non-infected diabetic foot ulcers (DFU): a health technology assessment (HTA).

AIMS: Assessment of the safety, efficacy and effectiveness of growth factors alone or in combination with other technologies in the treatment of DFU including medical, economical, social, ethical and juridical aspects. METHODS: We systematically searched relevant data bases limited to English and German language and publications since 1990. Review and assessment of the quality of publications followed methods conforming to widely accepted standards for evidence-based medicine and health economics. RESULTS: We identified 25 studies comparing becaplermin, rhEGF, bFGF and the metabolically active skin grafts Dermagraft and Apligraf with standard wound care (SWC) alone or extracellular wound matrix. Study duration ranged from 12 to 20 weeks and the study population comprised between 17 and 382 patients. Treatment with becaplermin, rhEGF, Dermagraft and Apligraf resulted in a higher incidence of complete wound closure and shorter time to complete wound healing with statistically significant differences. Regarding the proportion of adverse events there was no difference between treatment groups. The methodological quality of the studies was affected by significant deficiencies. Economic evaluations showed becaplermin being cost-effective. CONCLUSIONS: Add-on therapy with growth factors and active skin substitutes for treating uncomplicated DFU could be an alternative to SWC alone. For explicit recommendations further studies with stronger evidence are necessary.

Local tissue flaps: definitive treatment for chronic blisters after chemical burns.

Chronic blistering in grafted burn wounds is an infrequently described but severely debilitating complication that can appear after alkali burns and seems to coincide with a delay in initial treatment. Histological studies have concluded that the pathogenesis of chronic subepidermal blister formation in previously grafted burn wounds is related to abnormalities in the basement membrane. Although several reports have described this problem, none have reported adequate treatment for the chronic blistering in previously grafted alkali burns. The authors describe the case of a 30-year-old man in whom caustic soda burns treated with excision and split-thickness skin grafting resulted in chronic subepidermal blistering that failed to improve over the next 2 years. The problem was resolved with full-thickness skin excision and reconstruction with bipedicled fasciocutaneous flaps.

Two-step autologous grafting using HYAFF scaffolds in treating difficult diabetic foot ulcers: results of a multicenter, randomized controlled clinical trial with long-term follow-up.

This study evaluated the efficacy and tolerability of an autologous tissue-engineered graft--a 2-step HYAFF autograft--in the treatment of diabetic foot ulcers compared with standard care. In all, 180 patients with dorsal or plantar diabetic foot ulcers (unhealed for ≥1 month) were randomized to receive Hyalograft-3D autograft first and then Laserskin autograft after 2 weeks (n = 90; treatment group) or nonadherent paraffin gauze (n = 90; control group). Efficacy and adverse events were assessed weekly for 12 weeks, at 20 weeks, and at 18 months. The primary efficacy outcome was complete ulcer healing at 12 weeks. Wound debridement, adequate pressure relief, and infection control were provided to both groups. At 12 weeks, complete ulcer healing was similar in both groups (24% of treated vs 21% controls). A 50% reduction in ulcer area was achieved significantly faster in the treatment group (mean 40 vs 50 days; P = .018). Weekly percentage ulcer reduction was consistently higher in the treatment group. At 20 weeks, ulcer healing was achieved in 50% of the treated group as compared with 43% of controls. Dorsal ulcers had a 2.17-fold better chance of wound healing per unit time following autograft treatment (P = .047). In a subgroup with hard-to-heal ulcers, there was a 3.65-fold better chance of wound healing following autograft treatment of dorsal ulcers (P = .035). Adverse events were similar in both groups. The study results demonstrated the potential of this bioengineered substitutes to manage hard-to-heal dorsal foot ulcers.

The usefulness of the collagen and elastin sponge derived from salmon as an artificial dermis and scaffold for tissue engineering.

Collagen sponge is one of the medical materials that are frequently used in clinical medicine. However, the problem of prion disease harmfully affected the usage of mammals-derived medical materials. Since there have been no reports about prion disease occurring in marine products, we produced the collagen and elastin sponge (CES) made from salmon, and investigated whether the CES could be a substitute for mammalian collagen sponge. Fibroblasts were seeded in the CES to examine whether the CES could be used as a scaffold for tissue engineering. The results of the WST-1 assay showed that the fibroblasts were viable and were well proliferated in the CES. To examine whether the CES could be used as an artificial dermis, the CES and TERUDERMIS (traditional collagen sponge) were grafted onto the skin defects on the dorsum of rats. The histological findings of these ulcers showed non-significant difference between the CES and TERUDERMIS. Because of the safety, the abundance of the resources, and the possessing same ability as TERUDERMIS, the biomedical materials derived from marine products may be a substitute for those derived from mammals.

Parastomal hernia repair outcomes in relation to stoma site with diisocyanate cross-linked acellular porcine dermal collagen mesh.

PURPOSE: Biologic meshes are increasingly used in parastomal hernia repair. This study evaluates the efficacy and safety of diisocyanate cross-linked acellular porcine dermal collagen mesh for parastomal hernia repair, with particular reference to the relationship of the stoma site to the rectus sheath. METHODS: Hernias were repaired via a lateral approach, with onlay placement of the biologic mesh. A retrospective case note review and analysis of clinical outcomes was performed. The relationship of the stoma to the rectus sheath was determined by abdominal computed tomography (CT) and intraoperative findings. RESULTS: Over a 16-month period, 27 consecutive patients, median age 72 years, underwent parastomal hernia repair utilising onlay biologic mesh to reinforce the external oblique aponeurosis. There were 20 paracolostomy and seven paraileostomy hernias. Eleven stomas passed through the rectus sheath and 16 were lateral to it. Recurrences occurred in 3 of 11 stomas within and 12 of 16 stomas lateral to the rectus sheath (P = 0.022). The median time to recurrence was 10.1 months. The median follow up of patients without recurrence was 16.6 months (range 0.2-39.3). There was one perioperative death. One patient developed a superficial post-operative abscess that was managed conservatively, but there were no complications related to the biologic mesh and no mesh required removal. CONCLUSIONS: For parastomal hernias within the rectus sheath, diisocyanate cross-linked porcine dermal collagen mesh onlay repair gives good results and is safe to use. Repair of a parastomal hernia where the stoma is lateral to the rectus sheath has a significantly higher risk of recurrence and is not recommended.

Postoperative complications in prosthesis-based breast reconstruction using acellular dermal matrix.

BACKGROUND: Acellular dermal matrix has become a common adjunct in prosthesis-based breast reconstruction. The authors' aim was to determine whether acellular dermal matrix use in immediate prosthesis-based breast reconstruction is associated with higher rate of complications. METHODS: Over a 5½-year period at the Brigham and Women's Hospital, 470 postmastectomy defects were reconstructed immediately using tissue expanders or implants. These were divided into two groups: reconstructions with or without acellular dermal matrix. Data were collected on patient comorbidities, radiation, intraoperative tumescent solution use, prosthesis size, initial fill volume, and complications. RESULTS: The risk for major infections that required prosthesis removal was elevated in the acellular dermal matrix group (4.9 versus 2.5 percent), but this increase did not reach statistical significance (p = 0.172). There was a statistically significant increase in overall wound infection rate in the acellular dermal matrix group (6.8 versus 2.5 percent, p = 0.031), but in a multivariate analysis, the use of acellular dermal matrix did not materialize as a significant risk factor for overall wound infection. Overall surgical complication rate was significantly higher in the acellular dermal matrix group at 19.5 percent, compared with the non-acellular dermal matrix group at 12.3 percent (p < 0.001). Other significant risk factors for overall surgical complication included smoking, higher body mass index, higher initial volume, and larger implant size. CONCLUSIONS: Patient selection for prosthesis reconstruction involving acellular dermal matrix should be judicious, especially among smokers and patients with elevated body mass index. Even though the use of acellular dermal matrix allows higher initial volumes and reduced number of expansions, one should be careful about putting in too high of an initial volume.

Not all biologics are equal!

BACKGROUND: Although the efficacy of various biologic meshes in the abdominal reconstruction of complex ventral hernia has been shown, the performance profile of various biologic mesh scaffolds in terms of hernia-specific outcomes such as recurrence, mesh explantation, and mesh infections has not been examined. AIM: To evaluate the clinical outcomes of patients who underwent complex ventral hernia repair with bioprosthetic material. METHODS: This study is a retrospective analysis of the use of bioprosthetic material in complex ventral hernia at an academic institution from January 2002 to December 2007. RESULTS: A total of 58 patients with a mean age of 57.2 years and mean body mass index (BMI) of 33.8 who underwent reconstruction of ventral abdominal defects with a bioprosthetic from January 2002 to February 2009 were included in the study. The study patients had about 4.8 previous surgeries and 43.1% of patients had reconstruction in a setting of enterocutaneous fistula, while 46.6% had a previous mesh infection. Complex ventral hernia was seen in 50 patients, while eight patients had ventral and parastomal hernia. The type of biologic used for reconstruction was human-derived (AlloDerm, 29), porcine cross-linked (CollaMend, 3; Permacol, 2), and non-cross-linked porcine (Surgisis, 16; Strattice, 8). At least one complication was seen in 72.4% of patients. Major complications noted were surgical wound infections (19.0%), seroma (8.6%), and abscess formation (5.2%). The one-year hernia recurrence rate was 27.9% and mesh explantation was needed in 17.2% of patients. AlloDerm was less likely to be explanted (13.8%) or become infected (37.9%) but more likely to recur (28.6%) compared to porcine cross-linked bioprosthesis. Porcine cross-linked biologics were more likely to become infected (60%) and explanted (40%) but less likely to recur (20%) compared to AlloDerm. Non-cross-linked porcine biologics were less likely to be explanted (16.7%) but had higher recurrence (29.4%) compared to cross-linked porcine biologics and a higher infection rate (54.2%) compared to AlloDerm. CONCLUSIONS: The results from this study underscore the difficulty of repairing complex abdominal wall defects in contaminated fields. Cross-linked porcine biologics showed relatively higher infection and explantation rates. Equivalent recurrence and explantation rates were observed for the non-cross-linked porcine biologics and AlloDerm. These data indicate that there is currently no ideal biologic for complex ventral hernia repair.

An overview of methods for the in vivo evaluation of tissue-engineered skin constructs.

Cutaneous wounding often leads to contraction and scarring, which may result in a range of functional, cosmetic, and psychological complications. Tissue-engineered skin substitutes are being developed to enhance restoration of the skin and improve the quality of wound healing. The aim of this review is to provide researchers in the field of tissue engineering an overview of the methods that are currently used to clinically evaluate skin wound healing, and methods that are used to evaluate tissue-engineered constructs in animal models. Clinically, the quality of wound healing is assessed by noninvasive subjective scar assessment scales and objective techniques to measure individual scar features. Alternatively, invasive technologies are used. In animal models, most tissue-engineered skin constructs studied are at least evaluated macroscopically and by using conventional histology (hematoxylin-eosin staining). Planimetry and immunohistochemistry are also often applied. An overview of antibodies used is provided. In addition, some studies used methods to assess gene expression levels and mRNA location, transillumination for blood vessel observation, in situ/in vivo imaging, electron microscopy, mechanical strength assessment, and microbiological sampling. A more systematic evaluation of tissue-engineered skin constructs in animal models is recommended to enhance the comparison of different constructs, thereby accelerating the trajectory to application in human patients. This would be further enhanced by the embracement of more clinically relevant objective evaluation methods. In addition, fundamental knowledge on construct-mediated wound healing may be increased by new developments in, for example, gene expression analysis and noninvasive imaging.

Histomorphometric analysis of the phenotypical differentiation of recruited macrophages following subcutaneous implantation of an allogenous acellular dermal matrix.

This study aimed to clarify the phenotypical differentiation of recruited macrophages following subdermal implantation of an allogenous, acellular dermal matrix (aADM). In 20 male Wistar rats, one leg was randomly chosen for subcutaneous implantation of an aADM, while the other side received an autogenous dermis graft for control purposes. After 7 and 14 postoperative days, 10 animals were killed. Biopsies were obtained from the healing area and subjected to immunohistochemical staining (targets: pan macrophage marker CD68, M1 macrophage marker CD197, M2 macrophage marker CD163), histomorphometric analysis and reverse transcriptase polymerase chain reaction (targets: iNOS, arginase). No differences were detected in the total number of recruited macrophages between the groups. Allogenous ADMs significantly stimulated proinflammatory M1 differentiation, while autogenous dermis induced the regeneration promoting M2 phenotype. Proinflammatory M1 differentiation of macrophages might provide a potential explanation for profibrotic tissue deposition at the aADM interface following subcutaneous implantation, which has been observed previously.

Wound care: the role of advanced wound healing technologies.

Wound repair and regeneration is a highly complex combination of matrix destruction and reorganization. While major hurdles remain, advances over the past generation have improved the clinician's armamentarium in the medical and surgical management of this problem. The purpose of this manuscript is to review the current literature regarding the pragmatic use of three of the most commonly employed advanced therapies; namely, bioengineered tissue, negative pressure wound therapy, and hyperbaric oxygen therapy with a focus on the near-term future of wound healing, including stem cell therapy.

Reconstruction of defects following surgery for hypopharyngeal carcinoma using artificial biological material.

CONCLUSIONS: Use of artificial biological material ­ acellular dermal matrix (Alloderm, ADM) ­ combined with pectoralis major myocutaneous flaps (PMMFs) or other cervical tissue is a feasible technique with which to reconstruct a large circumferential defect involving the oral cavity and hypopharynx. OBJECTIVE: This paper presents a review of seven patients with advanced hypopharyngeal carcinoma treated at Tianjin Medical University Cancer Institute & Hospital, China, over a 4-year period. METHODS: ADM was used in the form of tissue patches for reconstruction. Five of the seven patients underwent total laryngectomy and total hypopharyngectomy, and reconstruction with a combination of PMMF and ADM tissue patches to restore hypopharyngeal functions. Two other patients underwent tumour resection. The defect in the posterior pharyngeal wall was reconstructed with ADM. Treatment details of the seven patients are discussed. RESULTS: All five PMMFs and seven ADM tissue patches survived. No pharyngeal fistula occurred. Satisfactory healing was observed between the wound margin and ADM 10 days after operation. The trauma area was completely covered by growing epithelium 18­37 days after operation. To some degree, stenosis of the pharyngeal cavity did occur, but patients could have a regular diet following dilatation of the stenosis. Five patients are free of disease after 18­42 months of follow-up.