Acellular dermal matrix: general principles for the plastic surgeon

Repeated Autologous Fat Grafting Significantly Increases Mastectomy Flap Thickness in Pre-Pectoral Multi-Stage Composite Expander-to-Implant Breast Reconstruction: Exploring the Concept of a Reverse Expansion

Background/Objectives: Combining autologous fat grafting with implant placement is meant to improve the quality of implant-based breast reconstruction. The present study explores the concept of multi-stage composite breast reconstruction with repeated sessions of autologous fat grafting to increase mastectomy flap thickness and provide better pre-pectoral implant coverage. Methods: Twenty-five consecutive patients underwent bilateral multi-stage composite expander-to-implant breast reconstruction and reverse expansion from August 2020 to April 2024. Subcutaneous thickness of the mastectomy flap was evaluated in predefined regions of interests of the breast on standardized MR images at two timepoints (before the first fat grafting session, with the tissue expander fully inflated, and 3 months after implant placement). Furthermore, the incidence of complications requiring surgery and implant-related complications were evaluated. All values are expressed as mean ± standard deviation, accepting statistical significance for a p-value < 0.05. Results: Patients underwent an average of 2.5 ± 0.6 fat grafting sessions, with a fat injection volume of 170 ± 60 mL per breast per session. The mean duration of the reconstructive process from mastectomy to final implant placement was 12 ± 5 months and the mean follow-up was 17 ± 8 months. The overall thickness of both breasts amounted to 190% of baseline thickness and was significantly higher in the upper breast quadrants than in the lower quadrants (p < 0.05). Tissue thickness increase correlated well with the number of fat grafting sessions and was independent of the patient's weight gain. Complications requiring surgery occurred in eight breasts during the reconstruction, with iatrogenic expander puncture being the most frequent (three cases, 6%). During follow-up, only one implant-related complication was observed (one case of bilateral rippling, 4%). No breast animation or symptomatic capsular contracture were observed. Conclusions: Multi-stage pre-pectoral composite expander-to-implant breast reconstruction using autologous fat grafting is an effective concept for breast reconstruction. Despite the need for multiple surgeries, the significant increase in subcutaneous tissue thickness, resulting in better soft tissue coverage, compensates for the longer reconstructive process.

Soft and Hard Tissue Stability Following Guided Bone Regeneration in an Active Orthodontics Patient

Guided bone regeneration (GBR) is a bone augmentation technique widely used in clinical practice to promote new bone growth by creating a conducive environment through bone grafts and barrier membranes. This article reports a case of a 14-year-old patient with significant bone loss, wound breakdown, and gingival recession in the anterior maxillary tooth, which was successfully treated through GBR combined with orthodontic treatment. This complex case of an area with bone defect required a multidisciplinary treatment in order to provide the best treatment for young patients.

Fish collagen sponge with human umbilical cord mesenchymal stem cells for diabetic wound repair in rats

Stem cell therapy offers a novel approach to treating difbetic foot ulcers. Fish skin decellularized matrix, a type I collagen, provides a promising carrier for stem cells, creating a supportive microenvironment that enhances cell survival and therapeutic potential. This study aims to investigate the effects and mechanisms of human umbilical cord mesenchymal stem cells (HUCMSCs) loaded onto a fish collagen sponge for wound healing in diabetic rats. The study evaluates stem cell-loading efficiency with fish collagen sponge in vitro, assesses material distribution on diabetic rat wounds, and establishes a wound model. Rats are divided into the Self-healing group, Fish collagen sponge group, and Sponge loaded with HUCMSCs group. Therapeutic effects are evaluated through various analyses, including histopathology and reverse transcription polymerase chain reaction for collagen-related gene expression levels. Compared to the self-healing group, both the fish collagen group and the composite group show faster wound repair and improved healing outcomes. The composite group exhibits superior wound healing quality, with fish collagen contributing to enhanced tissue regeneration through collagen regulation at the wound site. Loading HUCMSCs onto a fish collagen sponge shows promise for treating diabetic wounds by addressing nutrient deficiency and cell supply issues, offering potential benefits for patients undergoing treatment.

Extracellular matrix-based biomaterials in burn wound repair: A promising therapeutic strategy

Burns are common traumatic injuries affecting many people worldwide. Development of specialized burn units, advances in acute care modalities, and burn prevention programs have successfully reduced the mortality rate of severe burns. Autologous skin grafting has been considered as the gold standard for wound coverage after the removal of burned skin. For full-thickness burns of a larger scale, however, the autograft donor site may be quickly exhausted, so that alternative skin coverage is necessary. Although rapid progress has been made in the development of skin substitutes for burn wounds during the last decade, no skin substitute has fulfilled the criteria as a perfect replacement for the damaged skin. Extracellular matrix (ECM) derived components have emerged as a source for the engineering of biomaterials capable of inducing desirable cell-specific responses and one of the most promising biomaterials for burn wound healing. Among these, acellular dermal matrix, small intestinal submucosa, and amniotic membrane have been applied to treat burn wounds with acceptable outcomes. This review has explored the use of biomaterials derived from naturally occurring ECM and their derivatives for approaches aiming to promote burn wound healing, and summarized the ECM-based wound dressings products applicable in burn wound and postburn scar contracture to date.

Acellular Dermal Matrix without Basement Membrane in Immediate Prepectoral Breast Reconstruction: A Randomized Controlled Trial

BACKGROUND

Acellular dermal matrix (ADM) has become popular in various reconstructive procedures of different anatomic regions. There are different needs depending on the clinical application, including breast, abdominal wall, and any other soft-tissue reconstruction. Removal of the basement membrane, which consists of collagen fibers, may help achieve natural and soft breast reconstruction, which requires highly elastic ADMs. Given the lack of knowledge of the effectiveness of ADM without the basement membrane, the authors compared the clinical outcomes of ADMs with and without basement membrane in breast reconstruction.

METHODS

The authors conducted a single-blind randomized controlled trial to evaluate differences in clinical outcomes. The patients were randomized into 2 groups: ADM with or without basement membrane. Both groups underwent immediate prepectoral direct-to-implant breast reconstruction. Demographic characteristics, surgical outcomes, and breast shape change using nipple position were compared between the 2 groups.

RESULTS

A total of 56 patients were divided into 2 groups: ADM with basement membrane (n = 30 [53.6%]) or ADM without basement membrane (n = 26 [46.4%]). Clinical and surgical characteristics were similar between the 2 groups. The authors detected no statistically significant differences in the overall rate of complications or breast shape change between the 2 groups. However, the rate of seromas was higher in the ADM with basement membrane group than in the ADM without basement membrane group (10% versus 0%; P = 0.09).

CONCLUSIONS

The 2 groups showed similar surgical outcomes. ADM without basement membrane in implant-based breast reconstruction was safe, and had mechanical properties of lower tensile strength and higher elasticity.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, II.

Reconstructive breast implant-related infections: Prevention, diagnosis, treatment, and pearls of wisdom

Implant-based reconstructions are increasingly utilized following mastectomy in the prevention and treatment of breast cancer. However, these implants are associated with a high rate of infection, which is a major complication that can lead to implant removal, delay in adjuvant radiation and chemotherapy, and increase in health care costs. Early clinical signs and symptoms of infection, such as erythema, warmth, and tenderness, are challenging to discern from expected postsurgical responses. Furthermore, when atypical features are present or the patient's condition does not improve on adequate antimicrobials, the clinician should be prompted to consider an alternative noninfectious etiology. Herein we highlight the key elements of the preventive, diagnostic, and multidisciplinary therapeutic approach to salvaging the infected breast implant; review several infectious disease mimickers; and provide many pearls of wisdom that the practicing clinician must be familiar with and be able to manage in an effective and successful manner.

Pre-pectoral Breast Reconstruction: Surgical and Patient-Reported Outcomes of Two-Stages vs Single-Stage Implant-Based Breast Reconstruction

BACKGROUND

Two-stages pre-pectoral breast reconstruction may confer advantages over direct to implant (DTI) and subpectoral reconstruction in selected patients who have no indication for autologous reconstruction. The primary endpoint of the study was to evaluate and compare the incidence of capsular contracture in the pre-pectoral two-stages technique versus the direct to implant technique. Complications related to the two surgical techniques and patient satisfaction were also evaluated.

METHODS

A retrospective review of 45 two stages and 45 Direct-to-implant, DTI patients was completed. Acellular dermal matrix was used in all patients. An evaluation of anthropometric and clinical parameters, surgical procedures and complications was conducted. Minimum follow-up was 12 months after placement of the definitive implant.

RESULTS

There was no statistically significant difference in the rate of capsular contracture in the two groups. Rippling occurred more in DTI reconstruction. In the two-stages reconstruction, lipofilling was applied more often and there was a higher incidence of seroma. Patient satisfaction extrapolated from the Breast Q questionnaire was better for patients submitted to two-stage implant-based breast reconstruction.

CONCLUSION

Dual-stage pre-pectoral reconstruction with acellular dermal matrix appears to be a good reconstructive solution in patients with relative contraindications for one-stage heterologous reconstruction with definitive prosthesis and no desire for autologous reconstruction.

Acellular dermal matrix in urethral reconstruction

The management of severe urethral stricture has always posed a formidable challenge. Traditional approaches such as skin flaps, mucosal grafts, and urethroplasty may not be suitable for lengthy and intricate strictures. In the past two decades, tissue engineering solutions utilizing acellular dermal matrix have emerged as potential alternatives. Acellular dermal matrix (ADM) is a non-immunogenic biological collagen scaffold that has demonstrated its ability to induce layer-by-layer tissue regeneration. The application of ADM in urethral reconstruction through tissue engineering has become a practical endeavor. This article provides an overview of the preparation, characteristics, advantages, and disadvantages of ADM along with its utilization in urethral reconstruction via tissue engineering.

A Cohort Analysis of Early Outcomes After AlloDerm, FlexHD, and SurgiMend Use in Two-Stage Prepectoral Breast Reconstruction

BACKGROUND

Acellular dermal matrix (ADM) is frequently utilized in prepectoral breast reconstruction, but few studies have examined the role of ADM type in complication risk.

OBJECTIVES

This study was performed to determine the impact of ADM type on early complication rates in 2-stage alloplastic prepectoral breast reconstruction.

METHODS

We performed a cohort examination of all patients who underwent mastectomy with immediate 2-stage alloplastic prepectoral breast reconstruction with ADM support at Memorial Sloan Kettering Cancer Center from 2018 to 2021. ADM types utilized included AlloDerm (LifeCell Corporation, Branchburg, NJ), FlexHD (MTF Biologics, Edison, NJ), and SurgiMend (Integra LifeSciences Corporation, Princeton, NJ). Complication rates based on the number of tissue expanders (TEs) were determined for each ADM type. Performance of multivariate logistic regression determined the impact of ADM type on complication risk after accounting for confounders.

RESULTS

Overall, 726 patients (1054 TEs: 194 AlloDerm, 93 FlexHD, 767 SurgiMend) were included. The 3 cohorts differed in terms of mastectomy type (nipple-sparing: 23.5% of AlloDerm, 33.3% of FlexHD, 19.1% of SurgiMend, P = .038); ADM perforation (perforated: 94.8% of AlloDerm, 98.2% of FlexHD, 100% of SurgiMend, P < .001); and ADM size (AlloDerm: 153.2 cm2 [37.6], SurgiMend: 198.7 cm2 [10.4], FlexHD: 223.7 cm2 [37.9], P < .001). On univariate examination, no differences existed between ADM types for seroma, infection, exposure, malposition, or TE loss. Additionally, after adjustment for confounders with multivariate regression, no ADM type had higher odds of TE loss.

CONCLUSIONS

In this large cohort of prepectoral reconstruction patients, ADM type did not significantly affect the risk of complications. Additional prospective studies are warranted to better evaluate ADM choice for prepectoral breast reconstruction.

LEVEL OF EVIDENCE: 4

Prepectoral Versus Subpectoral Implant-Based Reconstruction: How Do We Choose?

Aspects of a patient's lifestyle, their state of health, breast size, and mastectomy skin flap quality are factors that influence the suggested plane of dissection in implant-based breast reconstruction. This article aims to review developments in prosthetic breast reconstruction and provide recommendations to help providers choose whether prepectoral or subpectoral reconstruction in the best approach for each of their patients.

Evolution of biomimetic ECM scaffolds from decellularized tissue matrix for tissue engineering: A comprehensive review

Tissue engineering is essentially a technique for imitating nature. Natural tissues are made up of three parts: extracellular matrix (ECM), signaling systems, and cells. Therefore, biomimetic ECM scaffold is one of the best candidates for tissue engineering scaffolds. Among the many scaffold materials of biomimetic ECM structure, decellularized ECM scaffolds (dECMs) obtained from natural ECM after acellular treatment stand out because of their inherent natural components and microenvironment. First, an overview of the family of dECMs is provided. The principle, mechanism, advances, and shortfalls of various decellularization technologies, including physical, chemical, and biochemical methods are then critically discussed. Subsequently, a comprehensive review is provided on recent advances in the versatile applications of dECMs including but not limited to decellularized small intestinal submucosa, dermal matrix, amniotic matrix, tendon, vessel, bladder, heart valves. And detailed examples are also drawn from scientific research and practical work. Furthermore, we outline the underlying development directions of dECMs from the perspective that tissue engineering scaffolds play an important role as an important foothold and fulcrum at the intersection of materials and medicine. As scaffolds that have already found diverse applications, dECMs will continue to present both challenges and exciting opportunities for regenerative medicine and tissue engineering.

Evaluation of wound healing effects of micronized acellular dermal matrix in combination with negative pressure wound therapy: In vivo study

Acellular dermal matrix (ADM) grafts can provide coverage for full-thickness skin defects and substitute for dermal defects. We tested the effectiveness of micronized ADM (mADM) as a dressing material, combined with negative pressure wound therapy (NPWT), for managing superficial wounds. We compared the wound healing effect of mADM in combination with NPWT with those of gelatin and mADM applied with a foam dressing. These therapeutic materials were applied to 36 cm² excisional wounds in a porcine full-thickness skin defect model. Wound healing kinetics and new tissue formation were assessed 10 days after the initial treatment by measuring the wound area. Collagen deposition and neovascularization were histologically evaluated. Compared with the other two groups, mADM plus NPWT combination group had a significantly larger wound area at the baseline (P = .0040), but the smallest on the 7th day (P = .0093). In addition, collagen formation and neovascularization were more histologically promoted than in the other two groups. mADM showed better results than the gelatin group but less collagen and revascularization than the combination group, and there was no significant difference in wound area. Our results show that the combination of mADM and NPWT has a synergistic wound healing effect.

Development of a full-thickness acellular dermal graft from human skin: Case report of first patient rotator cuff patch augmentation repair

The processing and initial testing of a new human tissue preparation is described. Full-thickness Acellular Dermal Matrix (ftADM) is the extracellular matrix (ECM) obtained by decellularization of full-thickness human skin from cadaveric donors. The safety, stability and usability of the graft are discussed with respect to the results of the residual cellular content, maintenance of ECM components, and biomechanical properties. Quantitative and qualitative analysis of the ECM demonstrated the absence of cell debris, while the native structure of human dermis was maintained. Biomechanical testing showed stiffness values comparable to other commercial products used for tendon reinforcement, suggesting that our ftADM could be successfully used not only in soft tissue regeneration surgeries, but also in tendon reinforcement. First case of ftADM in rotator cuff augmentation is described. Technical management of the patch during surgery and clinical outcomes are discussed.

Human Acellular Dermal Matrix in Reconstructive Surgery-A Review

Reconstructive surgery often confronts large tissue defects. This creates a need to look for materials that are immunogenic but offer the possibility of tissue filling. ADM-acellular dermal matrix-is a biological collagen matrix without immunogenicity, which is more commonly used in surgical treatment. Reconstructive surgery is still searching for various biocompatible materials that can be widely used in surgery. The available materials have their advantages and disadvantages. This paper is a literature review on the use of human acellular dermal matrix (ADM) in reconstructive surgery (surgical oncology, plastic and reconstructive surgery, and gynecologic reconstructive surgery). ADM appears to be a material of increasing use in various fields of surgery, and thus, further research in this area is required.

Co-Graft of Acellular Dermal Matrix and Split Thickness Skin Graft-A New Reconstructive Surgical Method in the Treatment of Hidradenitis Suppurativa

Hidradenitis suppurativa is a chronic disease that significantly reduces patients' quality of life. Patients are chronically treated with systemic therapies, which are often ineffective. Surgical treatment for severe cases of hidradenitis suppurativa is one option for affected patients. Surgical treatment has its limitations, and wound closure may be particularly problematic. This requires the use of reconstructive techniques. The methods of choice for wound closure are split-thickness skin grafts or local flaps reconstructions. However, each method has its limitations. This is a presentation of a new reconstructive surgical method in hidradenitis suppurativa surgery: the use of a co-graft of Acellular dermal matrix and split thickness skin graft as a novel method in wound closure after wide excisions, based on two cases. The results of this method are very promising: we achieved very fast wound closure with good aesthetic results regarding scar formation. In this paper, we used several examinations: laser speckle analysis, cutometer tests, and health-related quality of life (QoL) questionnaire to check the clinical impact of this method. Our initial results are very encouraging. ADM with STSG as a co-graft could be widely used in reconstructive surgery. This is a preliminary study, which should be continued in further, extended research.

"Tear-Drop Appearance" Wrap: A Novel Implant Coverage Method for Creating Natural Contour in Prepectoral Prosthetic-Based Breast Reconstruction

Various implant wrapping methods with acellular dermal matrix (ADM) have been introduced, but most focus on random trimming and suturing aimed to maximize implant coverage. Here we present our clinical experience using a “tear-drop appearance” wrapping method to achieve natural contours through upper pole volume replacement. We retrospectively reviewed the data of 56 consecutive cases of prepectoral prosthetic-based breast reconstruction (PPBR) using this wrapping method following nipple-sparing mastectomy between March 2020 and June 2021. The “tear-drop appearance” wrapping design creates an anatomical tear-drop–shaped pocket to encourage lower pole fullness and create a natural contour through upper pole volume replacement by ADM. Patients’ baseline characteristics, operative data, and complications were analyzed. Aesthetic outcomes were measured using the BREAST-Q and Aesthetic Item Scale (AIS). A successful reconstruction was achieved without major complications and using a single ADM sheet. Four types and three sizes of ADMs were used. The mean resected breast tissue weight was 274.3 g, while the mean implant volume was 230.0 cc. The average BREAST-Q and AIS scores were 4.6 ± 0.8 and 4.5 ± 0.7, respectively. Owing to its simplicity, reproducibility, and effectivity, this method is an excellent implant coverage option that achieves a natural contour in PPBR.

Abdominoplasty Panniculus as a Source for Human Acellular Dermis: A Preliminary Report

BACKGROUND

In extensive deep dermal burn injuries, split-thickness skin graft (STSG) has been the most preferred treatment option for resurfacing burn wounds. A thick split-thickness skin graft is ideal for preventing graft contracture but is associated with delayed donor healing and the lack of adequate donor skin. When applied with STSG, the dermal substitutes offer better-reconstructed skin than STSG alone. Human-derived acellular dermal matrix (HADM) obtained from cadaver skin is a dermal equivalent with good clinical outcomes. However, high cost and limited cadaver donor skin availability limit its clinical utility. Developing a low-cost preparation method and finding an alternate source of human donated skin can help reduce the cost. The objective of this study was to explore the feasibility of making HADM from abdominoplasty panniculus skin.

METHODS

Skin samples were collected from the abdominoplasty panniculus of ten eligible donors with their informed consent. A combination of low-cost reagents-sodium chloride and hypotonic solution (water for injection) was used for decellularizing the skin. Characterization of the prepared Acellular Dermis Matrix prototype was done.

RESULTS

The skin was deepidermized with one molar NaCl treatment at 37 °C for 24 h. The deepidermized dermis became acellular with hypotonic solution treatment at 4 °C for two weeks. The hematoxylin and eosin staining and cytotoxicity test confirmed the acellularity and non-cytotoxicity of the prepared HADM prototype. The HADM prototype also facilitated the formation of neo-epithelium in the 3D cell co-culture model.

CONCLUSION

This study confirms that abdominoplasty panniculus can be a viable alternative for HADM preparation. Further characterization studies are required to prove the concept.

Acellular Dermal Matrix Favorably Modulates the Healing Response after Surgery

SUMMARY

When first described for breast reconstruction, the presence of acellular dermal matrices (ADM) was associated with increased seroma formation and infection. However, clinical safety data has gradually improved with surgeon experience to an acceptable outcomes profile of ADM-assisted reconstruction when compared to submuscular implant coverage. In fact, ADM use potentially decreases capsular contracture rates and facilitates expansion for staged pre-pectoral breast reconstruction. Due to new regulatory requirements, the collection of unbiased, well-powered pre-market approval data summarizing long-term clinical outcomes will be essential over the coming years to understand the clinical performance of ADM usage in breast reconstruction.Currently, we can highlight the physiologic benefits of ADM use in breast reconstruction by evaluating the components of surgical wound healing that are favorably augmented by the implanted collagen substrate. ADM takes advantage of the wound healing cascade to incorporate into the patient's tissues - a process that requires a coordinated inflammatory infiltrate and angiogenesis. The presence of ADM augments and modulates the wound healing process to its advantage by simultaneously increasing the invasion of appropriate cellular constituents to facilitate expeditious healing and accelerate angiogenesis. Herein, we summarize the wound healing literature to demonstrate the mechanisms ADM use to biointegrate and the literature in which cellular constituents and soluble growth factors are upregulated in the presence of ADM. Lastly, we use our experimental observations of ADM incorporation to corroborate the literature.

Newly repairing technique of deformed hand by a posterior interosseous flap in an infant: A case report

Introduction

Many non-surgical methods were performed to repair the deformities in the skeletal system to avoid severe complications post-open surgery, especially within the childhood stage or below. We aim, in this case, to present a new technique for repairing bony deformities in the childhood stage, which fewer studies have to instigate its efficacy versus open surgery.

Case presentation

We present a 14-months-old infant with wrist extravasation injury at the neonatal stage (day 1), end with a right wrist volar contraction and complete loss of brain homunculus of the right hand.

Discussion

We used a reverse posterior interosseous flap to reconstruct the soft tissue and release the flexor tendons of the hand. The flap was conducted entirely and was rapidly adapted to the recipient beds to achieve good color and texture harmonies. Within following up for 12 weeks, the patient restored hand function.

Conclusion

More global cohort studies are required to compare precisely the efficacy between surgical options and the used technique in our case for salvaging deformities in childhood.

•

Many obstacles face the surgeons in children, especially among orthopedics.

•

Fewer studies have reported newly non-surgical methods due to repairing the bone deformities may cause severe complications among children.

•

This article aims to highlight the utility and versatility of the flap and to show the possibility of using this flap at the age of fewer than two years old group.

Review of 107 Oncoplastic Surgeries Using an Acellular Dermal Matrix with the Round Block Technique

The round block technique (RBT) is an oncoplastic surgery method that uses volume displacement techniques after partial mastectomy. However, cosmetic problems occur after tissue rearrangement in patients with small breasts or those in whom a large amount of breast tissue is excised. Therefore, we used an acellular dermal matrix (ADM) when the volume was insufficient after tissue rearrangement. Patients who underwent breast reconstruction using the ADM with the RBT after breast-conserving surgery (BCS) were included. The ADM graft was performed in two layers. First, it was placed on the glandular flap, and the patient was then seated to ascertain the degree of deformity. If the volume was insufficient, a graft was also performed under the skin flap. Overall, 107 oncoplastic surgeries were performed. Tumors were most commonly located in the upper outer quadrant of the breast, and the mean resected breast tissue was 27.1 g. Seroma was the most common complication, but it improved with several aspirations. There were no major complications or cosmetic problems requiring reoperation. Therefore, if the ADM was used for defects that could not be reconstructed with the RBT alone, safe and cosmetically good results could be obtained.

Application of Tilapia Skin Acellular Dermal Matrix to Induce Acute Skin Wound Repair in Rats

Extracellular matrix (ECM) material with good biological activity is essential to simulate cell growth microenvironment, induce cell infiltration and angiogenesis, and promote the repair of large area acute skin wound. In this study, tilapia skin acellular dermal matrix (TADM) was prepared to simulate ECM microenvironment, which can promote substantial area acute wound healing in rats. The main component of TADM is type I collagen, which has good physical and chemical properties, biological activity and cell adhesion. TADM is a form of biomaterial with low immunogenicity, low risk of prion infection and lower economic cost than other related materials such as mammalian collagen biomaterials. Our results show that TADM can guide cell infiltration, angiogenesis, regulate the expression and secretion of inflammatory and skin repair correlated factors to promote tissue healing.

Use of Biologic Agents in Nasal and Scalp Reconstruction

Oncologic reconstruction of the nose and scalp following Mohs micrographic surgery poses a significant challenge for plastic surgeons. While these defects are traditionally reconstructed using primary closure techniques, skin grafts, local flaps, pedicled flaps, and free tissue transfer, the incorporation of biologic healing wound agents such as Integra and Cytal provides patients and surgeons with alterative reconstructive options without additional donor site morbidity. Herein, we review the use of biologic agents used in soft tissue reconstruction of the nose and scalp following Mohs surgery.

Overview of Biologic Agents Used in Skin and Soft Tissue Reconstruction

Wound healing is a highly complex process mediated by cellular interactions at the microscopic level. Increased understanding of wound healing physiology has served as the foundation for translational research to develop biologic wound care technologies that have profoundly affected patient care. As the reader will see throughout this series in Seminars in Plastic Surgery , biologic wound technologies have broad applications and have greatly impacted the reconstructive ladder. Despite their frequent use, many surgeons lack familiarity with the myriad of products available on the market along with each product's relative advantages and shortcomings. This overview will discuss the classification of biologic wound agents used to reconstruct defects of the skin and soft tissue along with the advantages and disadvantages associated with their use.

Management of eyelid retraction related to thyroid eye disease

Eyelid retraction related to thyroid eye disease (TED) is a challenging condition. It is one of the main clinical signs and a major diagnostic criterion in TED. This condition may threaten vision due to exposure keratopathy, in addition to its esthetic alterations, which may lead to psychosocial implications and affect the patient's quality of life. Although it is more commonly observed in the upper eyelid, it may be present on both the upper and lower lids. Numerous surgical and nonsurgical treatment modalities have been described and will be reviewed in this article. Management should be based on an individual patient assessment, taking into consideration the disease stage, severity, and clinician experience.

Comparison of porcine and human acellular dermal matrix outcomes in wound healing: a deep dive into the evidence

Acellular dermal matrices (ADM) are a novel graft. The goal of this systematic review is to evaluate the evidence behind differences in human and porcine ADM, irrelevant of manufacturing method, and to determine if there is enough of an evidence base to change clinical practice. An extensive literature search was performed through MEDLINE and Embase with search terms defining a population, intervention and outcome. Title and abstract exclusion were performed with other exclusion criteria. In 191 articles were found after exclusion of duplicates, with only 29 remaining following exclusions. Ten studies were found to have level I and II evidence (I=3, II=8), of which two were histopathological, one was an animal model, one was a systematic review, and six were clinical. The remaining studies were reviewed and considered for discussion, but did not hold high enough standards for medical evidence. Strong clinical evidence already exists for the use of human ADM, but questions of access, cost, and ethics require consideration of a xenograft. Histopathologically, evidence suggests minimal long-term differences between human and porcine ADM, although there is a short acute immune response with porcine ADM. Clinically, there is limited difference in outcomes, with a small range in effect of different ADM preparations. Considering the effectiveness of ADM in wound healing, more high-level research with appropriate statistical analysis to facilitate a future meta-analysis is recommended to justify a transition from human to porcine ADM.

A New Treatment for the Reconstruction of the Medial Compartment of the Ankle: The Combined Use of Biological Materials

Fractures, especially if articular and periarticular, are frequently associated to functional and clinical disabling outcomes and chronic pain. In particular, the injuries with loss of bone, ligament, and/or tendon tissue in which the full recovery of the wound area is not obtained are the worst anatomical/pathological conditions to heal. In this study, three different biological materials were used as regenerative approaches to rebuild the medial malleolus fracture of the ankle in which loss of bone, ligament, and tendon tissue occur. In particular, the morselized human bone tissue was combined with the human dermis decellularized, both augmented with homologous platelet-rich plasma. The magnetic resonance imaging study with contrast at the follow-up showed a signal compatible with vascularization of the tissue without sign of degeneration. Our new regenerative approach in which different biological materials were combined together showed a good choice of treatment for the reconstruction of not repairable outcome of a fracture.

Clinical Applications of Allograft Skin in Burn Care

Allograft skin has been widely used for wound management in burn centers. Functional as biologic dressing, it can not only provide ideal temporary wound coverage in extensive burns when autograft is not immediately available but also prepare the wound bed for definitive autografting. In this article, the up-to-date clinical application of allograft in burn care was reviewed, including coverage of extensive burn wounds, combined use with meshed autograft, template for delayed application of cultured epidermal autografts, and the use of human acellular dermal matrix. Although it has potential disadvantages of rejection and disease transmission, allograft skin remains a workhorse in treatment of severe burn wounds.

The Biomechanical Properties of Meshed versus Perforated Acellular Dermal Matrices (ADMs)

Background:

Acellular dermal matrices (ADMs) are used for soft tissue augmentation across surgical specialties. Since allograft incorporation depends on direct opposition between the ADM and a vascular bed, seroma formation can be detrimental to incorporation. Since most ADM products are available in many meshed and perforated forms, there is a lack of consistency between manufacture designs. We set out to determine the fluid egress properties and increase in surface area resulting from common cut patterns.

Methods:

Three ADM cut patterns were studied: 1 meshed and 2 perforated. We calculated the surface area of these modified ADM samples. Fluid was passed through each ADM, and time required for fluid passage was recorded. An ANOVA (P < 0.05) was used to determine if there was a significant difference in egress properties across the 3 patterns.

Results:

Meshing in a 1:1 pattern resulted in a 97.50% increase in surface area compared with the uncut product. In comparison, only a 0.30% increase resulted from Perforation Pattern #1 and a 0.59% increase resulted from Perforation Pattern #2. There was a significant difference in egress properties across the three cut patterns (P = 0.000). The average egress time of Mesh Pattern #1 was 1.974 seconds. The average egress time of Perforation Pattern #2 was 6.504 seconds, and of Perforation Pattern #1 was 10.369 seconds.

Conclusions:

Quantitative comparison revealed that meshing ADM significantly improves fluid egress and increases the surface area. Therefore, the use of meshed ADM tissue could improve the incorporation of ADM with the recipient, with improved patient outcomes.

Use of Novel Decellularized Cadaveric Dermis (DCELL) in Single-Stage Resection and Reconstruction of Nonmelanomatous Skin Cancer of the Head and Neck

Reconstructive options in nonmelanomatous skin tumors of the head and neck region are limited in the frail, elderly patient group, where split skin thickness or full thickness grafts may not be a viable option. This study examines the use decellularized cadaveric dermis (DCELL), an acellular dermis product produced in the United Kingdom for the reconstruction of these skin defects. This was a single-center, prospective study of patients undergoing single stage wide local excision of nonmelanomatous skin cancer and reconstruction with decellularized dermis. Our inclusion criteria included any patient that required a curative excision but had risk factors where conventional local flap or free tissue transfer could have a potential adverse outcome. Thirty-seven wounds were treated with DCELL in 31 patients. Mean age was 81.6 years (range 61-94 years) and at the time of operation, 25 patients (80.7%) were ASA 3 or above. The scalp was the most common anatomical area operated on (n = 28, 75.7%). The overall proportion of wounds with complete closure was 89.2% (33 out of 37 wounds), with a failure rate of 10.8% (four complete graft failures). Device-related complications included one episode of crusting over the graft which resolved with topical antibiotics, and a hypertrophic scar over the wound edges. Cosmesis was satisfactory in all cases. DCELL demonstrated a very good take rate with equally satisfactory cosmetic outcomes in patients where standard reconstructive approaches may have adverse outcomes. Further research is needed to better define its role in the management of these skin cancers.

The Role of Collagen-Based Biomaterials in Chronic Wound Healing and Sports Medicine Applications

Advancements in tissue engineering have taken aim at treating tissue types that have difficulty healing naturally. In order to achieve improved healing conditions, the balance of exogenous matrix, cells, and different factors must be carefully controlled. This review seeks to explore the aspects of tissue engineering in specific tissue types treated in sports medicine and advanced wound management from the perspective of the matrix component. While the predominant material to be discussed is collagen I, it would be remiss not to mention its relation to the other contributing factors to tissue engineered healing. The main categories of materials summarized here are (1) reconstituted collagen scaffolds, (2) decellularized matrix tissue, and (3) non-decellularized tissue. These three groups are ordered by their increase in additional components beyond simply collagen.

Acellular dermal matrix in skin wound healing in rabbits - histological and histomorphometric analyses

OBJECTIVES

To analyze the histology and histomorphometry of healing associated with acellular dermal matrix in skin wounds in rabbits.

METHODS

Twelve male rabbits were divided into two groups: the control group (CG) and the matrix group (MG). Three skin wounds with a total area of 20 × 20 mm were created on the dorsal region of each animal. Photographic records of the lesions taken over a 21-day period and use of the ImageJ program allowed calculation of the wound contraction rate. The lesions were biopsied on days 3, 14 and 21 for histomorphometric analysis to define the thicknesses of the dermis and epidermis (hematoxylin-eosin) and calculate the densities of type I and type III collagen (picrosirius).

RESULTS

No significant difference in the healing rate was found between the groups (p>0.05). The MG presented greater epidermal thickness on day 3 (p<0.05) and on days 14 and 21 (p<0.001). The MG presented greater dermal thickness throughout the study period (p<0.05). The type I collagen density was higher in the MG throughout the study period (p<0.05), and the type III collagen density was higher in the MG on days 3 and 14 (p<0.05) and on day 21 (p<0.001).

CONCLUSION

The use of acellular dermal matrix increased the thickness of the dermal and epidermal layers and the amount of type I and III collagen during skin wound healing and did not alter the rate of wound contraction.

Comparison of Volume Retention and Biocompatibility of Acellular Dermal Matrix/Hyaluronic Acid Filler to Autologous Fat Grafts in a Mouse Model

BACKGROUND

Although fat grafting has become a widely used technique in aesthetic and reconstructive surgeries, resorption is still a challenge. Micronized acellular dermal matrix (ADM) has been considered as a stable, biocompatible soft tissue coverage material that can be used as a volume filler. Here, we compared the bioacceptance and sustainability of ADM hyaluronic acid (HA) filler with human fat graft in a mouse model.

METHODS

Harvested human fat and ADM/HA filler were injected randomly on the dorsal side of mice. Thirty-two mice were analyzed over a 7-week period with respect to volume, weight and microscopic evaluations with hematoxylin and eosin (H&E), epidermal growth factor (EGF) and vascular endothelial growth factor (VEGF) staining.

RESULTS

The volume and weight were maintained at 80% and 83%, respectively, in the ADM/HA filler group and 56.5% and 49.7%, respectively, in the fat-grafted group by the 7th week. There were no significant microscopic differences in inflammatory changes and granulation via H&E staining. At 1 and 2 weeks, EGF and VEGF immunostaining intensity scores were lower in the ADM/HA filler group. At 7 weeks, there were no significant differences in immunostaining intensity scores between the two groups.

CONCLUSIONS

During the 7-week experimental period, the ADM/HA filler showed no foreign body reaction and the proper volume was well maintained. This suggests that the ADM/HA filler can possibly be used in small amounts as an alternative to autologous fat grafts.

NO LEVEL ASSIGNED

This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authorshttp://www.springer.com/00266.

Decellularized Scaffolds for Skin Repair and Regeneration

The skin is the largest organ in the body, fulfilling a variety of functions and acting as a barrier for internal organs against external insults. As for extensive or irreversible damage, skin autografts are often considered the gold standard, however inherent limitations highlight the need for alternative strategies. Engineering of human-compatible tissues is an interdisciplinary and active field of research, leading to the production of scaffolds and skin substitutes to guide repair and regeneration. However, faithful reproduction of extracellular matrix (ECM) architecture and bioactive content capable of cell-instructive and cell-responsive properties remains challenging. ECM is a heterogeneous, connective network composed of collagens, glycoproteins, proteoglycans, and small molecules. It is highly coordinated to provide the physical scaffolding, mechanical stability, and biochemical cues necessary for tissue morphogenesis and homeostasis. Decellularization processes have made it possible to isolate the ECM in its native and three-dimensional form from a cell-populated tissue for use in skin regeneration. In this review, we present recent knowledge about these decellularized biomaterials with the potential to be used as dermal or skin substitutes in clinical applications. We detail tissue sources and clinical indications with success rates and report the most effective decellularization methods compatible with clinical use.

Acellular Dermal Matrix as a Definitive Reconstructive Option for Management of a Large Myelomeningocele Defect in the Setting of Severe Lumbar Kyphosis

BACKGROUND

Severe kyphosis is infrequently seen in neonates with myelomeningoceles. Spinal skeletal dysmorphology complicates repair, as local tissue may be insufficient to cover the dural repair. Although neonatal kyphectomy has been proposed as a potential solution to this problem, it carries significant potential risks that may not be acceptable to families.

CASE DESCRIPTION

A neonate presented with a large myelomeningocele defect with associated severe lumbar kyphosis. Kyphectomy was both declined by the family owing to the potential surgical risks and deemed not appropriate by the surgeons based on the challenging anatomic considerations. Soft tissue closure was not possible with local tissue rearrangement. Acellular dermal matrix was used as a definitive soft tissue coverage option, with complete epithelialization noted at 8 weeks postoperatively.

CONCLUSIONS

Acellular dermal matrix is a potentially useful adjunct for definitive reconstruction of complex neonatal soft tissue defects where local tissue is not available.

Hyaluronic acid hydrogel loaded by adipose stem cells enhances wound healing by modulating IL-1β, TGF-β1, and bFGF in burn wound model in rat

Application of hydrogels can be an effective technique in transferring the adipose-derived stem cells (ASCs) to injured tissue and their protection from further complications. Besides, acellular dermal matrix (ADM) has successfully been used in treatment of wounds. In this study, a combination of hylauronic acid (HA) and ASCs (HA/ASCs) was applied on burn wounds and the injured area was then covered by an ADM dressing in a rat model (ADM-HA/ASCs). Wound healing was evaluated by histopathological, histomorphometrical, molecular, biochemical, and scanning electron microscopy assessments on days 7, 14, and 28 post-wounding. ADM-HA/ASCs stimulated healing significantly more than the ADM-HA and ADM treated wounds, as it led to reduced inflammation, and improved angiogenesis and enhanced granulation tissue formation. Expression of interleukin-1β (IL-1β) and transforming growth factor-β1 (TGF-β1) was lower in the ADM-HA/ASCs treated wounds than the ADM-HA and ADM groups, at the seventh post-wounding day. ADM-HA/ASCs also enhanced the expression level of TGF-β1 mRNA at 14 day post-wounding that was parallel to the experimental data from histological and biochemical assessments and confirmed the positive role of ASCs in repair of burn wounds. Additionally, increase in basic fibroblast growth factor (bFGF) expression and decreased TGF-β1 level on the 28th post-wounding day indicated the anti-scarring activity of ASCs. HA loaded by adipose stem cells can represent a promising strategy in accelerating burn wound healing.

Predictors of Complications and Comparison of Outcomes Using SurgiMend Fetal Bovine and AlloDerm Human Cadaveric Acellular Dermal Matrices in Implant-Based Breast Reconstruction

BACKGROUND

Implant-based breast reconstruction with an acellular dermal matrix is one of the most common procedures performed by plastic surgeons. Although numerous matrices are available, there is little literature comparing them. This study compares the rates of complications between two commonly used products: AlloDerm (human cadaveric) and SurgiMend (fetal bovine) acellular dermal matrices.

METHODS

A retrospective review of a single center's 6-year experience was performed for consecutive, immediate breast reconstructions with acellular dermal matrix from 2009 to 2014. The authors compared demographics and surgical characteristics between patients receiving AlloDerm versus SurgiMend. Multivariate logistic regression was used to determine any association between type of matrix and surgical complications and to identify other clinical predictors for complications.

RESULTS

A total of 640 patients underwent 952 reconstructions using AlloDerm [578 breasts (61 percent)] or SurgiMend [374 breasts (39 percent)]. The average follow-up was 587 days. Multivariate analysis revealed that type of matrix was not an independent risk factor for the development of complications. However, smoking, age, radiotherapy, and initial tissue expander fill volume were associated with increased risk of postoperative complications.

CONCLUSIONS

Both AlloDerm and SurgiMend acellular dermal matrices demonstrate similar rates of major complications when used in immediate implant-based breast reconstruction. In contrast, preoperative radiation therapy, smoking, increasing age, and initial tissue expander fill volume are independent risk factors for postoperative complications. Reconstructive surgeons should take these findings into consideration when performing implant-based breast reconstruction with a dermal matrix.

Autologous Collagen Matrix (ACM): Lower Pole Support With a Supero-Anterior Capsular Flap in Secondary Subpectoral Breast Augmentation

Background

Secondary aesthetic breast surgery is a complex and challenging scenario. It requires the surgeon to identify contributing factors, provide patient education, make a further management plan, and optimize the conditions for a favorable result. Various techniques have been described in literature but the rate of reoperation is still high. The first author has been using a supero-anterior capsular flap with a neopectoral subcapsular pocket and an implant change in these cases.

Objectives

To review the patient characteristics, indications, and early results of using part of the existing implant capsule for secondary subpectoral breast augmentations.

Methods

All patients who underwent secondary breast augmentation, over a period of 2 years by the first author (P.M.), using the supero-anterior capsular flap technique were included. The technique involves dissection of a new subpectoral pocket and uses the existing implant capsule as an internal brassiere.

Results

A total of 36 patients were operated by this technique. Of these, 17 patients had developed a complication while 19 patients wanted a change in size only. At a mean follow up of 10.2 months, there was no bottoming out, double bubble, or capsular contracture.

Conclusions

This reliable technique provides stable results as shown by low rate of complications with the existing follow up.

Level of Evidence 4

Do Processing Methods Make a Difference in Acellular Dermal Matrix Properties?

BACKGROUND

The use of acellular dermal matrices (ADMs) has become the standard of practice in many reconstructive and aesthetic surgical applications. Different methods used to prepare the allograft tissue for surgical use can alter the ADMs natural properties. Aseptic processing has been shown to retain the natural properties of ADMs more favorably than terminally sterilized ADMs. Terminal sterilization has been historically linked to alteration of biological materials. In vitro work was conducted to compare ADM processing methods.

OBJECTIVES

Characterize aseptically processed ADMs and compare cell-matrix interaction characteristics to terminally sterilized ADMs.

METHODS

Two aseptically processed ADMs, FlexHD Pliable and BellaDerm, were characterized via histological evaluation, biomechanical integrity, enzymatic degradation, and in vitro cell studies. FlexHD Pliable was compared to Alloderm Ready-to-Use (RTU).

RESULTS

Histological evaluation revealed that FlexHD Pliable had a uniform, open structure compared to BellaDerm. Mechanical characterization demonstrated that BellaDerm had higher strength and stiffness compared to FlexHD Pliable, which maintained higher elasticity. Immunohistochemical analysis verified that key matrix proteins remained intact after aseptic processing. Cell studies found that fibroblasts attached more readily, and proliferated faster on FlexHD Pliable compared to BellaDerm. Additionally, fibroblasts infiltrated into FlexHD Pliable from both sides and on the dermal side in BellaDerm and produced an abundance of multi-layered matrix proteins (collagen, fibronectin) when compared to AlloDerm RTU which was sparse.

CONCLUSIONS

Aseptically processed FlexHD Pliable and BellaDerm provide a suitable, biocompatible option for tissue repair and regeneration in aesthetic and reconstructive surgical applications.

440 Consecutive immediate, implant-based, single-surgeon breast reconstructions in 281 patients: a comparison of early outcomes and costs between SurgiMend fetal bovine and AlloDerm human cadaveric acellular dermal matrices

BACKGROUND

A 2010 nationwide survey of plastic and reconstructive surgeons indicated that approximately 83 percent performed predominantly implant-based breast reconstruction, with acellular dermal matrix used by approximately half of those practitioners. Although the medical literature documents well over 2000 cases of breast reconstruction with matrices, relatively few cases using other than human cadaveric acellular dermal matrices have been reported. The author compared complications and costs using SurgiMend fetal bovine and AlloDerm human cadaveric acellular dermal matrices.

METHODS

A retrospective review of a single surgeon's 5-year experience was performed for consecutive, nonrandomized immediate breast reconstructions with acellular dermal matrix from 2005 to 2010.

RESULTS

Two hundred eighty-one patients had 440 implant-based reconstructions using SurgiMend [222 patients (79.0 percent)] or AlloDerm [59 patients (21.0 percent)]. No significant differences in complication rates were observed between SurgiMend and AlloDerm for hematoma, infection, major skin necrosis, or breast implant removal. Seroma was the most prevalent complication; the seroma rate for AlloDerm (15.7 percent) was significantly greater than that for SurgiMend (8.3 percent). Using recent product costs for equivalently sized AlloDerm and SurgiMend units, the cost of SurgiMend was $1024 less per breast than AlloDerm.

CONCLUSIONS

SurgiMend fetal bovine and AlloDerm human cadaveric acellular dermal matrices demonstrate similar rates of major early complications in breast reconstruction in this study. This similarity in complication rates between SurgiMend and AlloDerm and the cost savings seen with the use of SurgiMend are factors for the surgeon to consider in choosing a matrix for breast reconstruction.

CLINICAL QUESTION/LEVEL OF EVIDENCE

: Therapeutic, III.