An Integrative Therapeutic Concept for Surgical Treatment of Severe Cases of Lymphedema of the Lower Extremity.

BACKGROUND: Lymphedema results from insufficient lymphatic drainage and typically affects the extremities. Recent studies revealed obesity as another cause of extremity lymphedema. Conservative treatment of patients with elephantiastic lymphedema of the lower extremity is limited and often inadequate. Resecting surgery plays an important role in these cases. Here, we investigated the effects of an integrated therapy concept on outcome and complication rates. METHODS: We retrospectively analyzed the clinical outcome of 26 patients with elephantiastic lymphedema of the lower limb who underwent a complex decongestive physical therapy (CDP) perioperatively and reduction surgery in our clinic between 1998 and 2011. We subsequently compared these patients (group A) with a control group of 30 patients (group B) who received medial thigh lift due to post-bariatric or aesthetic issues between 2011 and 2013. The incidence of complications, reoperations, blood transfusion, and duration of hospital stay was analyzed. All patients in group A received CDP perioperatively in a specialized lymphological clinic. RESULTS: Both groups are comparable in terms of age and sex. Patients significantly differ in terms of BMI (p < 0.001). Thirty-six reductive procedures were performed in group A and 30 in group B. We did not see any significant difference in the incidence of complications (p = 1.000) and the rate of postoperative blood transfusions (p = 0.116). CONCLUSIONS: We were able to show that an integrative concept including surgery is a good additional option for the treatment of severe cases of lymphedema in appropriate candidates. Furthermore, an adequate perioperative conservative setting helps to minimize possible complications.

Co-culture of adipose-derived stem cells and endothelial cells in fibrin induces angiogenesis and vasculogenesis in a chorioallantoic membrane model.

Neovascularization of adipose tissue equivalents is a crucial step in successful adipose tissue engineering, since insufficient vascularization results in graft resorption in an in vivo situation. A possible cellular approach to overcome this limitation is the co-implantation of adipose-derived stem cells (ASCs) with endothelial cells to stimulate the formation of a vascular network. We investigated the potential of ASCs derived from human abdominal fat tissue co-cultured with endothelial progenitor cells (EPCs) from human peripheral blood to stimulate neovascularization of fibrin constructs on the chorioallantoic membrane (CAM) of fertilized chicken eggs, in direct comparison to human umbilical vein endothelial cells (HUVECs). After 9 days of incubation, cell-fibrin constructs were explanted and histologically evaluated with respect to ingrowth of avian blood vessels into the construct and formation of human blood vessels by co-implanted endothelial cells. When administered on the CAM, ASCs successfully guided host vasculature into the construct (angiogenesis) and guided formation of capillary-like structures by co-implanted human endothelial cells (vasculogenesis), with HUVECs being superior to EPCs, leading to a perfused avian and human capillary network within the fibrin construct. However, the results also showed that perfused human blood vessels were only observed near the CAM compared to unperfused capillary-like structures near the top of the construct, indicating that perfusion of the cell-fibrin construct takes longer than 9 days. In conclusion, as blood vessel formation is an essential step during adipogenic differentiation, the data support our hypothesis that cellular communication between transplanted ASCs and endothelial cells is beneficial for vasculogenesis. Copyright © 2013 John Wiley & Sons, Ltd.

Utilization of a genetically modified muscle flap for local BMP-2 production and its effects on bone healing: a histomorphometric and radiological study in a rat model.

AIM OF THE STUDY: We developed an experimental rat model to explore the possibility of enhancing the healing of critical-size bone defects. The aim of this study was to demonstrate the feasibility of this concept by achieving high local BMP-2 expression via a transduced muscle flap that would facilitate bony union while minimizing systemic sequelae. METHODS: The transduction potential of the adenoviral vector encoding for BMP-2 was tested in different cell lines in vitro. In vivo experiments consisted of harvesting a pedicled quadriceps femoris muscle flap with subsequent creation of a critical-size defect in the left femur in Sprague-Dawley rats. Next, the pedicled muscle flap was perfused with high titers of Ad.BMP-2 and Ad.GFP virus, respectively. Twelve animals were divided into three groups comparing the effects of Ad.BMP-2 transduction to Ad.GFP and placebo. Bone healing was monitored radiologically with subsequent histological analysis post-mortem. RESULTS: The feasibility of this concept was demonstrated by successful transduction in vitro and in vivo as evidenced by a marked increase of BMP-2 expression. The three examined groups only showed minor difference regarding bone regeneration; however, one complete bridging of the defect was observed in the Ad.BMP-2 group. No evidence of systemic viral contamination was noted. CONCLUSIONS: A marked increase of local BMP-2 expression (without untoward systemic sequelae) was detected. However, bone healing was not found to be significantly enhanced, possibly due to the small sample size of the study.

Treatment of male genital lymphedema: an integrated concept.

Genital lymphedema is a debilitating condition. Currently, therapeutic concepts include conservative and surgical measures of genital volume reduction, but no therapy standards exist. The aim of this study was to analyze our experience with the treatment of male genital lymphedema and to describe our integrated concept, which combines perioperative complex decongestive physiotherapy (CDP) with surgical reduction. We conducted a retrospective study of 51 male patients who were treated in our clinic between 1998 and 2013, acquiring data on etiology, performed therapy, and complication rates. Forty-three (84%) of our patients suffered from primary and eight (16%) from secondary lymphedema. Two patients (4%) exhibited isolated penile affection and 22 (43%) isolated scrotal affection, while the majority (27 or 53%) exhibited penoscrotal lymphedema. All patients underwent inpatient CDP preceding and following surgery. Surgical therapy involved debulking the scrotum in 25 patients (49%), isolated penile reduction in two (4%), and penoscrotal reduction in 24 (47%). Hydrocoelectomy was performed in 22 (43%) patients. Following resection of the diseased tissue, the defects were closed primarily using adjacent healthy skin. There was no need for local flaps or skin grafts. Three patients suffered from complications requiring revision surgery: hematoma in two patients (4%) and wound dehiscence in one (2%). We measured the change in quality of life that was achieved by these procedures using the Glasgow Benefit Inventory questionnaire. The patients reported improvement in general functioning and physical health, whereas the social support score was largely unaffected by the procedure. Our results show that genital lymphedema patients can be reliably treated by combining conservative and surgical therapy. Prior conservative reduction of the genitals facilitates surgery and allows consistent results at a low complication rate, whereas surgical reduction serves to enhance and stabilize the results of conservative treatment.

Comparison between endothelial progenitor cells and human umbilical vein endothelial cells on neovascularization in an adipogenesis mouse model.

Volume stability and growth of tissue engineered adipose tissue equivalents using adipose-derived stem cells (ASCs) rely strongly on angiogenesis and neovascularization to support the maintenance of cells. An attractive cellular approach is based on coimplantation of endothelial cells to create a vascular network. Endothelial progenitor cells (EPCs) are a promising cell population, since they can be easily isolated from autologous human peripheral blood and thus represent a clinically feasible option. We have previously shown in in vitro and semi-in vivo studies that ASCs exert beneficial effects on EPCs in terms of enhanced tube formation and formation of blood vessels, respectively. In this study, we investigated the in vivo effects of coimplantation on endothelial cell-mediated neovascularization and ASC-mediated adipose tissue formation. For this purpose, human ASCs and human EPCs (or HUVECs as direct comparison to EPCs) were suspended alone or in coculture in fibrin and subcutaneously injected into the back of athymic nude mice and explanted after 1, 3 or 6months. Our results show that monocultures of EPCs or HUVECs were not able to perform vasculogenesis and constructs exhibited complete resorption already after 1month. However, a remarkable difference between EPCs and HUVECs was detected when coimplanted with ASCs. While coimplanted HUVECs gave rise to a stable neovasculature which was characterized by perfusion with erythrocytes, coimplanted EPCs showed no ability to form vascular structures. In the case of HUVEC-derived neovasculature, coimplanted ASCs displayed perivascular properties by stabilizing these neovessels. However, formation of human adipose tissue was independent of coimplanted endothelial cells. Our results indicate that HUVECs are superior to EPCs in terms of promoting in vivo neovascularization and recruiting perivascular cells for vessel stabilization when coimplanted with ASCs.

Human adipose-derived stem cells enhance the angiogenic potential of endothelial progenitor cells, but not of human umbilical vein endothelial cells.

One of the current challenges in the field of adipose tissue engineering is to promote sufficient vascularization to prevent cell death and to support adipose tissue formation. Thus, a novel strategy to enhance neovascularization of tissue-engineered adipose tissue might be the coimplantation of adipose-derived stem cells (ASCs) with endothelial progenitor cells (EPCs). However, no knowledge is given about the cellular interaction in vitro of human ASCs derived from subcutaneous fat tissue and EPCs derived from human peripheral blood. In this study, the first aim was to characterize ASCs and EPCs. Secondly, the two-dimensional Matrigel assay and the three-dimensional spheroid sprouting assay were applied for analyzing the ASC-EPC interaction in regard to formation of capillary-like structures by EPCs by ASC-conditioned medium (CM) or coculture of both cell types and compared to cocultures of ASCs and human umbilical vein endothelial cells (HUVECs). ASC-CM had no influence on the formation of capillary-like structures by EPCs. However, coculture with ASCs significantly enhanced the formation of capillary-like structures by EPCs; an effect that was not observed in cocultures of ASCs with HUVECs. Importantly, this increase in capillary-like structure formation by EPCs due to cell-cell contact was associated with significantly increased vascular endothelial growth factor (VEGF) secretion and VEGF-A mRNA expression, while inhibition of VEGF receptor tyrosine kinases completely abolished this effect. In conclusion, these data suggest that cellular communication occurs between ASCs and EPCs triggered by cell-cell contact or at least close proximity, which is partially mediated by secreted VEGF leading to the enhancement of angiogenic properties in EPCs, but not in HUVECs.

Infraareolar pectoralis major myocutaneous island flap as treatment of first choice for deep sternal wound infection.

Deep sternal wound infection (DSWI) is a grave complication of median sternotomy, associated with high morbidity, mortality and escalating treatment costs. There is general consensus that optimal treatment comprises radical debridement followed by coverage with a vascularised flap. However, there is ongoing debate regarding the ideal operative procedure. We present our experience with the infraareolar pectoralis major island myocutaneous flap (PEC-MI flap) as treatment of first choice in DSWI. Following a retrospective chart review, data pertaining to patient demographics, type of cardiac surgery performed, prevalence of known DSWI risk factors, identified pathogens, duration of surgery, flap-related complications, duration of hospital stay and antibiotic therapy, as well as mortality were noted. Additionally, we describe the operative technique and review the relevant literature. Twenty-five patients underwent coverage with the PEC-MI flap in our department. The average age was 69.2 years. Nineteen patients underwent coronary artery bypass surgery, 10 valve replacement, two aortic replacement surgery and one pericardiectomy. In six cases, no internal mammary artery was used in cardiac surgery, in 11 cases one and in seven cases both internal mammary arteries were used. The average duration of surgery was 154.2 min and the average hospital stay was 28.4 days. Complications which required revision surgery were haematoma in three cases, one wound dehiscence and one recurrent infection. Two cases required coverage with an additional regional flap. The PEC-MI flap has been used as flap of first choice in our clinic for treatment of DSWI. It is sufficient to raise the flap unilaterally, and it does not require skin grafting. The combination of immunocompetent bulky muscle tissue used to obliterate the sternal cavity and the large skin paddle enabling a low-tension skin closure allows reliable and efficient treatment of this severe complication.

Human endothelial progenitor cells induce extracellular signal-regulated kinase-dependent differentiation of mesenchymal stem cells into smooth muscle cells upon cocultivation.

Neovascularization represents an important issue in tissue-engineering applications, since survival of implanted cells strongly relies on sufficient oxygen and nutrient supply. We have recently observed that human bone marrow-derived mesenchymal stem cells (MSCs) support neovessel formation originating from coimplanted endothelial cells (ECs) in vivo, suggesting that MSCs may function as perivascular cells by investing and stabilizing nascent EC-derived neovessels. In this study, we investigated EC-induced mural cell differentiation of MSCs in vitro. For this purpose, endothelial progenitor cells (EPCs) from two different origins, namely adult peripheral blood (pbEPCs) and neonatal cord blood (cbEPCs), or human umbilical vein endothelial cells (HUVECs), were cocultured with human MSCs to analyze the effect on MSC differentiation toward a smooth muscle cell (SMC)/pericyte phenotype. EPCs as well as HUVECs increased alpha-smooth muscle actin expression in MSCs upon cocultivation in a time-dependent manner. This effect was strongly dependent on direct cell-to-cell contact and extracellular signal-regulated kinase (ERK) signaling, but was not mediated by heterotypic gap junction communication. Beyond enhanced SMC marker gene expression in MSCs, EPCs also enhanced the functional characteristics of cocultured MSCs by increasing their ability to attach to EC tubes in vitro. In conclusion, our study has shown that EPCs from adult peripheral blood as well as from cord blood commit cocultivated MSCs toward an SMC/pericyte phenotype in a cell-contact- and ERK-dependent manner.

Monitoring molecular changes induced by ischemia/reperfusion in human free muscle flap tissue samples.

BACKGROUND: Our current knowledge of the pathophysiological sequelae of ischemia or reperfusion (I/R) injury in free tissue transfer in reconstructive surgery is based on data obtained in animal experiments. In this study, we investigated the histologic and molecular changes after 11 free microsurgical muscle transfers in human muscle tissue. METHODS: Biopsies of free muscle flap tissue were taken immediately before clipping of the pedicle and 5 days after ischemia and successful microanastomosis and restoration of the blood flow. Samples were analyzed histologically for edema formation and by immunohistochemistry for infiltration of inflammatory cells and angiogenesis. Expression levels of the inflammatory marker proteins interleukin-1ß and tumor necrosis factor α and of complement component 3 as a major mediator of I/R injury were analyzed by real-time polymerase chain reaction. A TUNEL (terminal desoxynucleotidyl transferase-mediated-dUTP-nick-end-labeling) assay was used to assess apoptosis levels within the human muscle tissue. RESULTS: I/R injury leads to a significant up-regulation of inflammatory parameters, infiltration of inflammatory cells, and angiogenesis. Increased complement component 3 deposition and apoptosis of cells were accompanied by interstitial edema as indication for a pronounced postischemic inflammatory reaction within the muscle tissue after free tissue transfer. CONCLUSIONS: Our findings of molecular changes induced by I/R injury in human striated muscle tissue validate data obtained in animal models of I/R injury. The parameters and inflammatory patterns defined in this study will allow for the monitoring of the success of novel pharmaceutical strategies in the future and will help to transfer data obtained in animal work to the in vivo setting in human beings.

An integrated therapy concept for reduction of postoperative complications after resection of a panniculus morbidus.

BACKGROUND: Panniculus morbidus is characterized by an edematous, painful hanging abdominal mass, due to laxity and redundancy of the abdominal skin in morbid obesity, particularly after massive weight loss. Panniculectomy, by wedge resection, is a salvage procedure with high satisfaction rates though associated with high complication rates. Here we investigated the effects of perioperative complex decongestive physical therapy (CDP) on outcome and complication rates. METHODS: We retrospectively analyzed the clinical course and outcome of 24 patients receiving panniculectomy between 1998 and 2009 in our department of plastic surgery. Sixteen patients received perioperative CDP, and eight patients did not receive any form of decongestive treatment. We analyzed the incidence of complications, reoperation, blood transfusions, and length of hospital stay based on chart reviews. Complications were categorized as minor or major according to the necessity of readmission or reoperation. CDP was performed for 4-6 weeks preoperatively and 2 weeks postoperatively. RESULTS: The incidence of major complications (p = 0.001), the rate of postoperative blood transfusions (p = 0.028), wound healing disorders (p = 0.021), and the incidence for complications (p = 0.001), whether minor or major, were significantly reduced in the CDP group. In summary, 12 of 16 patients within the CDP group had an uneventful course, whereas all non-CDP patients had at least one complication. CONCLUSIONS: Adequate perioperative CDP treatment in a lymphological clinic may reduce the rate of early postoperative complications after resection of panniculus morbidus.

Bone formation and neovascularization mediated by mesenchymal stem cells and endothelial cells in critical-sized calvarial defects.

Bone represents a highly dynamic tissue whose development is strongly dependent on vasculogenic and angiogenic processes. Neovascularization also plays an important role in fracture healing and in tissue engineering applications aiming at restoring bone function. We have previously shown in a heterotopic subcutaneous implantation model of severe combined immunodeficiency (SCID) mice that implanted human umbilical vein endothelial cells (HUVECs) gave rise to the formation of a complex functional human neovasculature. In this study, we investigated the effect of HUVEC coimplantation on mesenchymal stem cell (MSC)-mediated bone regeneration in an orthotopic calvarial bone defect model in immunocompromised mice. For this purpose, human fibrin/Matrigel-immobilized HUVECs and MSCs were seeded alone or in combination into scaffolds consisting of decalcified processed bovine cancellous bone (Tutobone) and implanted into calvarial critical-sized defects. Our results show that implanted HUVECs formed complex three-dimensional networks of perfused human neovessels that were stabilized by recruiting perivascular cells. Neovessel formation was considerably higher in the coimplantation group, suggesting that implanted MSCs supported HUVEC-triggered neovascularization. In addition, implanted MSCs effectively supported bone formation in calvarial defects. However, the HUVEC-derived neovasculature did not improve MSC-triggered bone regeneration in this orthotopic critical-sized defect model.

Correlation between complication rate and patient satisfaction in abdominoplasty.

Abdominoplasty has become one of the most frequently performed procedures for improving body contour. Numerous reports exist focusing on postoperative complications with even more studies suggesting technical modifications to decrease their occurrence. However, the impact of complications on patient satisfaction has not been sufficiently addressed to date. A retrospective analysis was performed investigating the occurrence of complications following abdominoplasty and their effect on patient satisfaction. Patient satisfaction was assessed by means of the client satisfaction questionnaire-8. From June 1994 to April 2004 a total of 139 patients underwent an abdominoplasty. Minor and major complications were encountered in 40 (28.8%) and 16 (11.5%) patients, respectively. The median client satisfaction questionnaire-8 score among those patients with and without complications was 29. Thus, it seems that postoperative complications after abdominoplasty do not negatively affect patient satisfaction.

The "rising-sun-technique" in abdominoplasty.

A multitude of studies has been published focusing on different technical aspects of abdominoplasty. However, rarely has attention been drawn to skin closure techniques and its implications on postoperative scar length and complication rate. A retrospective analysis was conducted comparing a new comprehensive approach to skin closure with conventional techniques. Patients in each study group were matched for race, body mass index, gender, medical history, and smoking habits. We focused on postoperative scar length and rate of wound healing problems. Forty-six patients were included in each study group. Patients in whom wound closure was achieved via the technique presented here displayed a mean scar length of 33.68 cm (vs. 49.92 cm) and wound healing problems in 8.7% (vs. 23.9%). A marked reduction of scar length and postoperative wound healing problems is achievable with application of the technique presented in this article.

Nipple reconstruction: evidence-based trials in the plastic surgical literature.

Although many technical descriptions of nipple reconstruction exist in the medical literature, insufficient evidence-based data are present about the outcome. This study aimed to identify randomized controlled trials (RCTs) and controlled clinical trials (CCTs) in the plastic surgical literature addressing nipple reconstruction, and to elucidate whether a hand search was superior to an extensive database search in retrieving all pertinent studies. The hand search included analysis of all "original articles" published in four of the leading plastic surgery journals from January 1990 to December 2005, with subsequent identification of RCTs and CCTs. Additionally, a computerized search was conducted including the following databases: PubMed, Web of Science, and Evidence-Based Medicine Reviews. From a total of 10,476 published original articles in four plastic surgery journals over a 16-year period, only one RCT was identified that addressed nipple reconstruction. The database search, however, retrieved two trials: the RCT identified by hand search and one CCT. The impact of nipple reconstruction is well described in the literature. However, it is astonishing that the plastic surgical literature lacks evidence-based trials addressing this issue. Clearly, more evidence-based trials are necessary to ensure that recommendations for a particular technique are based on solid scientific data.

In vitro analysis of the interactions between preadipocytes and endothelial cells in a 3D fibrin matrix.

The volume-persistent survival of transplanted adipose tissue in vivo relies on early vascularization, due to an otherwise early induction of apoptosis of the centrally located cells. Thus, one way to enable the early formation of a capillary network resulting in a sufficient perfusion of the transplanted construct might be the co-transplantation of autologous preadipocytes with endothelial cells. To investigate preadipocyte-endothelial cell interaction, three-dimensional proliferation- and angiogenesis assays were performed in vitro. Proliferation rates of co-cultured endothelial cells and preadipocytes suspended in a fibrin matrix were elucidated by Alamarblue assays. The spheroid angiogenesis model was applied for analyzing the effects of vascular endothelial cell growth factor (VEGF) and basic fibroblast growth factor (bFGF) (produced by preadipocytes) as well as the impact of cell-cell interaction between preadipocytes and endothelial cells and fibrin matrix on endothelial cell migration. Preadipocytes proliferated in fibrin glue, whereas endothelial cells underwent apoptosis. By co-culturing, both cell types demonstrated an increased proliferation rate. Preadipocytes provoked migration of endothelial cells. Blocking bFGF and/or VEGF led to a significant decrease of migration. Changes in fibrin structure were followed by migration of single cells instead of sprouting. An appropriate fibrin matrix as well as already differentiated endothelial cells are necessary for preadipocytes to develop their angiogenic activity via bFGF and VEGF.