A retrospective evaluation of 182 free flaps in extremity reconstruction and review of the literature.

Introduction: During the past decades, free flaps have been given a central role in the reconstructive surgery. Especially in the extremities, where there is a scarcity of available tissues for local flaps, free flaps play a central part. The aim of this study was to evaluate the risk factors contributing to partial and total flap failure. Patients and methods: In a retrospective cohort study, all data concerning patients who underwent free flap reconstruction of the extremities during the first five years since the founding of the department of plastic surgery were gathered. Patient- and surgery-related risk factors were analyzed in correlation to the postoperative complications. Results: In total, 182 free flaps were included in this study. Partial and total flap failure were noted in 21.42% and 17.03%, respectively. A correlation was seen between the time lapsed from debridement until flap coverage, with flaps performed between day 4 and 14 having the least quote of flap failure (p=0.022). Gender, age, arterial hypertension, nicotine abuse, diabetes mellitus, peripheral arterial disease and the number of anastomosed veins were not significantly associated with free flap failure. Conclusion: Our study showed that free flaps can be safely performed in healthy patients as well as in patients with risk factors, with an acceptable flap loss rate. Randomized controlled studies are needed to clarify the exact role of each risk factor in free flap surgery.

Fibrin Sealant Artiss Compared to Progressive Tension Sutures With Stratafix in the Management of Wound Drainage Following Post-Bariatric Body-Contouring Surgery.

BACKGROUND: Post-bariatric body-contouring surgery is one of the most rapidly growing areas in plastic surgery. One of the most common complications following post-bariatric body-contouring surgery is seroma. There are a number of approaches to reducing wound drainage and seroma formation. A promising strategy to reduce these complications is to develop effective methods for reducing dead space between the tissue layers. METHODS: We conducted a retrospective trial assessing the use of human fibrin sealant Artiss in comparison to progressive tension sutures (PTS) with Stratafix, a bidirectional barbed suture device in patients undergoing post-bariatric body-contouring surgery. Thirty-six patients for abdominoplasty or lower-body-lift were evaluated. Treatment patients underwent procedure with fibrin sealant applied to adapt the tissue layers. Control patients underwent an identical procedure but with PTS. Primary outcome measures included total wound drainage and time to drain removal. RESULTS: The use of Artiss in abdominoplasty was associated with a mean drain volume that was significantly higher and more days that were needed to remove all drains compared to the PTS group. In body-lift, the mean drain volume and number of days needed to remove all drains tended to be higher when using Artiss compared to the PTS group. CONCLUSION: The use of Artiss in post-bariatric body-contouring surgery did not decrease the rate of seromas and the length of time required for post-surgical drains when compared to PTS.

HISTORIQUE: L'opération de remodelage corporel après une opération bariatrique fait partie des interventions à la croissance la plus rapide en chirurgie plastique. Le sérome en est l'une des principales complications. Il existe plusieurs méthodes pour réduire le drainage des plaies et la formation de sérome. Des méthodes efficaces pour réduire l'espace mort entre les couches de tissus sont une stratégie prometteuse. MÉTHODOLOGIE: Les chercheurs ont réalisé une étude rétrospective pour comparer la colle Artiss à base de fibrine humaine aux sutures de tension progressive (STP) à l'aide du Stratafix, un fil de suture cranté bidirectionnel, pour les patients qui subissent un remodelage corporel après une opération bariatrique. Ils ont évalué 36 patients qui devaient subir une abdominoplastie ou un remodelage du bas du corps. Les patients traités se sont fait appliquer de la colle à base de fibrine humaine pour adapter les couches de tissus. Le groupe témoin a subi la même intervention, mais au moyen de STP. Les mesures de résultats primaires incluaient le drainage total des plaies et la période jusqu'au retrait du drain. RÉSULTATS: En cas d'abdominoplastie, l'utilisation d'Artiss entraînait un volume de drainage moyen considérablement plus élevé et un plus grand nombre de jours avant de retirer tous les drains que la STP. En cas de remodelage corporel, le volume de drainage moyen et le nombre de jours nécessaire avant de retirer tous les drains tendaient à être plus élevés après l'utilisation d'Artiss que de STP. CONCLUSION: Par rapport aux STP, l'Artiss n'a pas réduit le taux de sérome ni la période d'utilisation des drains après des opérations de remodelage corporel suivant une chirurgie bariatrique.

Fluorescence in situ Hybridization (FISH) in the Microbiological Diagnostic of Deep Sternal Wound Infection (DSWI).

PURPOSE: Postoperative mediastinitis after cardiac surgery is still a devastating complication. Insufficient microbiological specimens obtained by superficial swabbing may only detect bacteria on the surface, but pathogens that are localized in the deep tissue may be missed. The aim of this study was to analyze deep sternal wound infection (DSWI) samples by conventional microbiological procedures and fluorescence in situ hybridization (FISH) in order to discuss a diagnostic benefit of the culture-independent methods and to map spatial organization of pathogens and microbial biofilms in the wounds. METHODS: Samples from 12 patients were collected and analyzed using classic microbiological culture and FISH in combination with molecular nucleic acid amplification techniques (FISHseq). Frequency of and the time to occurrence of a DSWI was recorded, previous operative interventions, complications, as well as individual risk factors and the microbiologic results were documented. RESULTS: Tissue samples were taken from 12 patients suffering from DSWI. Classical microbiological culture resulted in the growth of microorganisms in the specimens of five patients (42%), including bacteria and in one case Candida. FISHseq gave additional diagnostic information in five cases (41%) and confirmed culture results in seven cases (59%). CONCLUSION: Microbial biofilms are not always present in DSWI wounds, but microorganisms are distributed in a "patchy" pattern in the tissue. Therefore, a deep excision of the wound has to be performed to control the infection. We recommend to analyze at least two wound samples from different locations by culture and in difficult to interpret cases, additional molecular biological analysis by FISHseq.

Hyperspectral Imaging (HSI) as a new diagnostic tool in free flap monitoring for soft tissue reconstruction: a proof of concept study.

OBJECTIVES: Free flap surgery is an essential procedure in soft tissue reconstruction. Complications due to vascular compromise often require revision surgery or flap removal. We present hyperspectral imaging (HSI) as a new tool in flap monitoring to improve sensitivity compared to established monitoring tools. METHODS: We performed a prospective observational cohort study including 22 patients. Flap perfusion was assessed by standard clinical parameters, Doppler ultrasound, and HSI on t0 (0 h), t1 (16-28 h postoperatively), and t2 (39-77 h postoperatively). HSI records light spectra from 500 to 1000 nm and provides information on tissue morphology, composition, and physiology. These parameters contain tissue oxygenation (StO2), near-infrared perfusion- (NIR PI), tissue hemoglobin- (THI), and tissue water index (TWI). RESULTS: Total flap loss was seen in n = 4 and partial loss in n = 2 cases. Every patient with StO2 or NIR PI below 40 at t1 had to be revised. No single patient with StO2 or NIR PI above 40 at t1 had to be revised. Significant differences between feasable (StO2 = 49; NIR PI = 45; THI = 16; TWI = 56) and flaps with revision surgery [StO2 = 28 (p < 0.001); NIR PI = 26 (p = 0.002); THI = 56 (p = 0.002); TWI = 47 (p = 0.045)] were present in all HSI parameters at t1 and even more significant at t2 (p < 0.0001). CONCLUSION: HSI provides valuable data in free flap monitoring. The technique seems to be superior to the gold standard of flap monitoring. StO2 and NIR PI deliver the most valuable data and 40 could be used as a future threshold in surgical decision making. Clinical Trial Register This study is registered at the German Clinical Trials Register (DRKS) under the registration number DRKS00020926.

[Implementation of the wide awake local anesthesia no tourniquet (WALANT) type of anesthesia in hand surgery]. / Einsatz der WALANT("wide awake local anesthesia no tourniquet")-Narkoseart in der Handchirurgie.

Wide awake local anesthesia no tourniquet (WALANT) refers to an anesthesia technique with low bleeding and complication rates, which enables interventions on the hand in an awake patient without the use of a tourniquet. Bleeding control is achieved through addition of vasoconstrictors to the infiltration solution. Since the motor function of the extremity is not affected, it offers the additional possibility of intraoperative active function testing. The WALANT procedure constitutes an established, effective, easily learnt and resource-sparing technique. The spectrum of surgical possibilities with WALANT is wide and covers nearly all elective and many emergency procedures. Due to multiple advantages in contrast to other regional and general anesthesia procedures, WALANT features an increasing spectrum of surgical applications and practitioners. It is therefore of interest for hand surgeons working both in hospitals and private practices.

Quality of Life After Bilateral Risk-Reducing Mastectomy and Simultaneous Reconstruction Using Pre-Pectoral Silicone Implants.

PURPOSE: Bilateral risk-reducing mastectomy (BRRM) can reduce the risk of developing breast cancer by up to 95% in women with increased exposure. Although survival is increased, mastectomies can adversely affect a patient physically, psychologically, and psychosexually. High health-related quality of life (HRQoL) is often achieved after simultaneous breast reconstruction (BR) following BRRM; however, data on the pre- and postoperative results of HRQoL are lacking. Therefore, we investigated the quality of life, esthetic outcome, and patient well-being after BRRM and simultaneous implant-based BR. PATIENTS AND METHODS: Of the 35 patients who underwent skin-sparing or nipple-sparing mastectomy between May 2012 and December 2017 at a university hospital, only 22 completed the evaluation. Baseline data and data on previous operations and operation techniques were retrieved from the patient's charts. BREAST-Q and short form-36 health survey (SF-36) questionnaires were used to evaluate patient satisfaction and HRQoL. RESULTS: SF-36 analysis showed a significantly higher score for pain (p=0.043) in our population than in the general female population. Comparing the pre- and postoperative BREAST-Q results, a significant decrease in the physical well-being of the chest (p=0.0179) and a slight improvement in breast satisfaction were observed (p=0.3266). All patients were well-satisfied with the postoperative outcome, reconstruction, and perioperative surgeon care. CONCLUSION: Bilateral mastectomy with simultaneous BR using pre-pectoral implants is associated with an HRQoL similar to that of the healthy population. Although bilateral mastectomy may have an immense effect on the psychological, physical, and social aspects, immediate BR preserves the outer appearance and improves self-esteem.

Free Flap Reconstruction of the Extremities in Patients Who are ≥65 Years Old: A Single-Center Retrospective 1-to-1 Matched Analysis.

PURPOSE: Demographic changes are leading to population aging, and free flap reconstructions for various indications are expected to become increasingly common among older patients. Therefore, this study evaluated free flap reconstruction of the extremities in older patients and compared the outcomes to those from younger patients who underwent similar procedures during the same period. PATIENTS AND METHODS: This single-center retrospective study used a case-control design to compare older and younger patients who underwent free flap reconstruction of soft tissue defects in the extremities. One-to-one matching was performed for older patients (≥65 years) and younger patients (≤64 years) according to indication, flap recipient site, and flap type. The parameters of interest were clinico-demographic characteristics, flap type, defect location, indication for free flap reconstruction, number of venous anastomoses, and postoperative complications (flap loss, infection, and wound healing disorders). RESULTS: The study included 48 older patients and 133 younger patients, with a mean follow-up of 12 months after discharge. The free flap reconstruction was performed at a mean interval of 19.8±22.8 days (range: 0-88 days). The 1:1 matching created 38 pairs of patients, which revealed no significant differences in the rates of flap necrosis and flap failure. CONCLUSION: This study failed to detect a significant age-related difference in the flap necrosis rate after free flap reconstruction of extremity defects. Therefore, with careful perioperative management and patient selection, microsurgical free flap reconstruction is a feasible option for older patients.

[Surgical flap according to Littler (neurovascular island flap)]. / Lappenplastik nach Littler (neurovaskulärer Insellappen).

OBJECTIVE: Defect coverage of medium-sized soft tissue defects on the ulnar side of the thumb and radial side of the index finger. By using the Littler flap, both, the lost soft tissue coverage and sensitivity, which is necessary for an exact grip to the long fingers, can be simultaneously restored. INDICATIONS: Medium-sized soft tissue defect of the ulnar tip of the thumb, exposed bones and parts of the tendons, extensive soft tissue defects with sensory deficit. CONTRAINDICATIONS: Limiting accompanying injuries of the hand. SURGICAL TECHNIQUE: All-layer incision of the flap at ulnar 3rd digit with proximal exploration of the nerve and vascular bundle. Tracing the bundle to the exit from the palmar arch. After subcutaneous tunneling, shift of the flap into the defect. POSTOPERATIVE MANAGEMENT: Immobilization of the thumb in adduction for 7 days in a dorsal plaster splint, followed by free exercise. RESULTS: Reliable defect coverage with low donor-site morbidity and immediate restoration of sensibility in the ulnar tip of the thump. However, microsurgical dissection, especially of the nerve, is challenging.

Secreted Factors from Adipose Tissue Reprogram Tumor Lipid Metabolism and Induce Motility by Modulating PPARα/ANGPTL4 and FAK.

Recent studies indicate that adipose tissue in obesity promotes breast cancer progression by secreting protumorigenic chemokines, growth factors, and fatty acids. However, the detailed mechanisms by which hypertrophic adipose tissue influences breast cancer cells are still not well understood. Here we show that co-culture with adipose tissue from high-fat diet induced obese C57BL/6 mice alters transcriptome profiles in triple-negative breast cancer (TNBC) cells, leading to upregulation of genes involved in inflammation and lipid metabolism, such as IL1B, PLIN2, and ANGPTL4. Similar results were obtained by treating TNBC cells with adipose tissue conditioned media (ACM) generated from fat tissue of obese female patients. Many of the upregulated genes were activated by PPAR nuclear receptors, as shown by pathway analyses and gene expression experiments using PPAR agonists and antagonists. Metabolic analysis revealed that TNBC cells cultivated with ACM had significantly higher levels of ß-oxidation. Furthermore, ACM-treated TNBC cells displayed a pronounced aggressive cell phenotype, with enhanced wound healing, proliferation, and invasion capabilities. ACM-induced invasion was dependent on the PPAR-target ANGPTL4 and activated FAK signaling, as shown by ANGPTL4 depletion and FAK inhibition. Together, our data suggest that factors released by adipose tissue change PPAR-regulated gene expression and lipid metabolism and induce a more aggressive TNBC cell phenotype. These effects are, at least in parts, mediated by fatty acids provided by the adipose tissue. IMPLICATIONS: Adipose tissue provides factors for increased progression of TNBC cells, identifying PPAR- and FAK-signaling as potential novel targets for treatment of TNBC, especially in obese women.

Examination of ex-vivo viability of human adipose tissue slice culture.

Obesity is associated with significantly higher mortality rates, and excess adipose tissue is involved in respective pathologies. Here we established a human adipose tissue slice cultures (HATSC) model ex vivo. HATSC match the in vivo cell composition of human adipose tissue with, among others, mature adipocytes, mesenchymal stem cells as well as stroma tissue and immune cells. This is a new method, optimized for live imaging, to study adipose tissue and cell-based mechanisms of obesity in particular. HATSC survival was tested by means of conventional and immunofluorescence histological techniques, functional analyses and live imaging. Surgery-derived tissue was cut with a tissue chopper in 500 µm sections and transferred onto membranes building an air-liquid interface. HATSC were cultured in six-well plates filled with Dulbecco's Modified Eagle's Medium (DMEM), insulin, transferrin, and selenium, both with and without serum. After 0, 1, 7 and 14 days in vitro, slices were fixated and analyzed by morphology and Perilipin A for tissue viability. Immunofluorescent staining against IBA1, CD68 and Ki67 was performed to determine macrophage survival and proliferation. These experiments showed preservation of adipose tissue as well as survival and proliferation of monocytes and stroma tissue for at least 14 days in vitro even in the absence of serum. The physiological capabilities of adipocytes were functionally tested by insulin stimulation and measurement of Phospho-Akt on day 7 and 14 in vitro. Viability was further confirmed by live imaging using Calcein-AM (viable cells) and propidium iodide (apoptosis/necrosis). In conclusion, HATSC have been successfully established by preserving the monovacuolar form of adipocytes and surrounding macrophages and connective tissue. This model allows further analysis of mature human adipose tissue biology ex vivo.

Clinical and Microbiological Analysis of Deep Sternal Wound Infections in Fifty-Two Consecutive Patients.

Background: Mediastinitis after cardiac surgery can lead to devastating consequences such as deep sternal wound infections (DSWI). Staphylococcus epidermidis and other coagulase-negative staphylococci belong to the physiological skin flora and therefore generally are not considered pathogenic agents. Thus, local resistance patterns of these bacterial species often recovered from wound specimens generally are ignored while choosing antibiotics for peri-operative prophylaxis in cardiac surgery as well as in the selection of empiric antibiotic therapy of DSWI. Methods: During the period May 2012-May 2013, 52 patients suffering from DSWI were treated at our institution. For every patient, deep tissue samples were obtained during surgical debridement procedures and submitted to microbiologic analysis. The frequency of and the time to occurrence of a DSWI was recorded, and baseline data, previous operative interventions, complications, and the technique used for soft tissue reconstruction, as well as the microbiologic results and individual risk factors, were documented. Results: There were 32 male patients (62%) and 20 female. The patients' age at the time of revision was a mean of 67 ± 11.5 years (range 35-83 years). There was bacterial growth in 31 cases (60%), the predominant species being S. epidermidis (20 patients; 65%). Extended antibiotic therapy was indispensable to controlling the infection. Conclusion: The local resistance patterns of antibiotics should have a greater influence on the standardized prophylaxis or empirical therapy of DSWI and need to be discussed specifically for this high-risk population. Because of its multi-resistance spectrum, S. epidermidis must be classified as a potential pathogen. In the cases reported here, extended antibiotic therapy was necessary to support wound healing and thus good patient outcomes.

Deep sternal wound infection - latissimus dorsi flap is a reliable option for reconstruction of the thoracic wall.

BACKGROUND: At present, data describing patients' long-term outcomes, quality of life, and survival after deep sternal wound infection are rarely available. The purpose of our study was to evaluate functional outcome and patient well-being after debridement and reconstruction of the sternal defect using a pedicled latissimus dorsi flap following deep sternal wound infection (DSWI). METHODS: This retrospective analysis reviewed 106 cases of DSWI after open-heart surgery treated between May 1, 2012, and May 31, 2015. The parameters of interest were demographic and medical data, including comorbidity and mortality. Follow-up consisted of physical examination of the patients using a specific shoulder assessment, including strength tests and measurements of pulmonary function. RESULTS: The population consisted of 69 (65%) male and 37 (35%) female patients. Their average age at the time of plastic surgery was 69 years (range: 35-85). The 30-day mortality was 20% (n = 21); after one-year, mortality was 47% (n = 50), and at follow-up, it was 54% (n = 58). Heart surgery was elective in 45 cases (42%), urgent in 31 cases (29%) and for emergency reasons in 30 cases (28%). The preoperative European System for Cardiac Operative Risk Evaluation (EuroSCORE) averaged 16.3 (range: 0.88-76.76). On the dynamometer assessment, a value of 181 Newton (N) (±97) could be achieved on the donor side, in contrast to 205 N (±91) on the contralateral side. The inspiratory vital capacity of the lung was reduced to an average of 70.58% (range: 26-118), and the forced expiratory volume in 1 s was decreased to an average of 69.85% (range: 38.2-118). CONCLUSIONS: Given that only small adverse effects in shoulder function, strength, and pulmonary function were observed, the latissimus dorsi flap appears to be a safe and reliable option for the reconstruction of the sternal region after DSWI.

Single cell study of adipose tissue mediated lipid droplet formation and biochemical alterations in breast cancer cells.

Obesity is a known risk factor for breast cancer and a negative prognostic factor for cancer recurrence and survival. Several studies demonstrated that aggressive breast tumor cells contain higher numbers of intracellular lipid droplets (LDs). Here we applied simultaneous visualization, identification and quantification of the lipid accumulation in lipid droplets (LDs) of aggressive, human triple-negative MDA-MB-231 breast cancer cells treated with adipose tissue-conditioned medium (ACM) derived from overweight and obese patients. In addition to Oil Red O and AdipoRed fluorescent staining, label-free confocal Raman microspectroscopy (CRM) has been applied. CRM enables imaging of cell compartments as well as quantification and monitoring of specific biomolecules and metabolic processes on a single cell level. Interestingly, breast cancer cells incubated with ACM showed a significantly higher number of intracellular LDs. Cultivation of breast tumor cells with ACM of obese patients induced the formation of LDs with a 20-fold higher lipid concentration than cultivation with basal medium. This is in line with the significantly higher levels of NEFAs (non-esterified fatty acids) detected in the ACM obtained from obese patient compared to ACM obtained from overweight patients or basal medium. Further, by principal component analysis, we identified a significant increase in unsaturation, esterification and lipid to protein ratio in LDs in breast cancer cells incubated with ACM. CRM analyses might function as a valuable diagnostic tool to identify metabolic alterations in biological samples which in turn could provide more detailed insights in the pathogenesis of breast cancer in association with obesity.

Standardized Musculocutaneous Flap for the Coverage of Deep Sternal Wounds After Cardiac Surgery.

BACKGROUND: Deep sternal wound infection remains a serious complication after cardiac surgery, leading to increased morbidity, mortality, and cost. The goal of our study was to develop a standardized, reproducible method to safely cover deep sternal wounds and ensure improved healing rates. METHODS: The study was developed as a retrospective cohort study. We included 58 patients who received standardized latissimus dorsi flap coverage of a sternum defect wound after poststernotomy mediastinitis at our institution between September 2015 and June 2017. RESULTS: The average age of the cohort was 66.75 years, and 51.72% of patients were men. The mean hospital stay was 26.83 days. Eight patients (14.75%) died during the hospital stay due to sepsis or heart failure. The average flap size was 137.13 cm2. The mean operative time was 155 minutes. Seventy-four percent of patients developed a seroma at the donor site, which was treated conservatively with compression garments and taps, and 7% of patients developed a wound dehiscence of the donor site, which was treated conservatively with dressings. The mean follow-up time was 15 weeks. All 50 surviving patients showed complete wound healing on follow-up. CONCLUSIONS: The latissimus dorsi pedicled flap is a safe, reproducible technique for coverage of deep sternal wounds, with few relevant perioperative complications. By setting definite parameters for the flap dissection and by ensuring a reliable blood supply, our method enables the coverage of these complex wounds by an interdisciplinary team in any cardiovascular surgical setting.

Qualitative and Quantitative Analysis of Cardiac Progenitor Cells in Cases of Myocarditis and Cardiomyopathy.

We aimed to identify and quantify CD117+ and CD90+ endogenous cardiac progenitor cells (CPC) in human healthy and diseased hearts. We hypothesize that these cells perform a locally acting, contributing function in overcoming medical conditions of the heart by endogenous means. Human myocardium biopsies were obtained from 23 patients with the following diagnoses: Dilatative cardiomyopathy (DCM), ischemic cardiomyopathy (ICM), myocarditis, and controls from healthy cardiac patients. High-resolution scanning microscopy of the whole slide enabled a computer-based immunohistochemical quantification of CD117 and CD90. Those signals were evaluated by Definiens Tissue Phenomics® Technology. Co-localization of CD117 and CD90 was determined by analyzing comparable serial sections. CD117+/CD90+ cardiac cells were detected in all biopsies. The highest expression of CD90 was revealed in the myocarditis group. CD117 was significantly higher in all patient groups, compared to healthy specimens (*p < 0.05). The highest co-expression was found in the myocarditis group (6.75 ± 3.25 CD90+CD117+ cells/mm2) followed by ICM (4 ± 1.89 cells/mm2), DCM (1.67 ± 0.58 cells/mm2), and healthy specimens (1 ± 0.43 cells/mm2). We conclude that the human heart comprises a fraction of local CD117+ and CD90+ cells. We hypothesize that these cells are part of local endogenous progenitor cells due to the co-expression of CD90 and CD117. With novel digital image analysis technologies, a quantification of the CD117 and CD90 signals is available. Our experiments reveal an increase of CD117 and CD90 in patients with myocarditis.

[Pedicled Omentum Flaps in the Management of Deep Sternal Wound Infections]. / Der gefäßgestielte Omentumlappen zur Behandlung tiefer sternaler Wundinfekte.

AIM: Coverage of a deep sternal wound infection with a greater omentum flap. Due to a persistent infection caused by an infected aortic prosthesis, the primarily performed reconstruction with a latissimus dorsi flap had to be revised, and an alternative solution had to be found. INDICATION: A deep sternal wound infection is a rare but devastating complication following median sternotomy. If the commonly used muscle flap is not sufficient and artificial material is still present in the wound, for instant drivelines or a vascular prosthesis, the greater omentum flap is a useful option due to its immunologic capacity. METHOD: After an exploration of the persisting infected deep sternal wound, a radical debridement is performed followed by a jet lavage. The soft tissue from the greater omentum is prepared via median laparotomy and transferred through a tunnel created in the diaphragm. Then it is pulled into the wound cavity and can be used for tension-free sheathing of the aortic prosthesis. The previously used muscle flap can additionally be used for superficial soft tissue coverage. CONCLUSION: Due to its immunologic competence, the greater omentum flap is a good treatment alternative to the commonly used muscle flaps in defects with infected artificial material.

Double-Pedicled Free Deep Inferior Epigastric Perforator Flap for the Coverage of Thigh Soft-Tissue Defect.

Soft-tissue defects caused by radiation injury are a challenging task for the reconstructive surgeon, due to the extent of the soft-tissue damage and the associated injuries of the local blood vessels and bone tissue. We present the application of the versatile deep inferior epigastric perforator (DIEP) flap for the coverage of an extended lateral thigh soft-tissue defect after the surgical resection of an undifferentiated pleomorphic high-grade sarcoma, neoadjuvant chemotherapy, and adjuvant chemo- and radiotherapy. A double-pedicled free DIEP flap (756 cm2) was harvested and anastomosed to the transverse branch of the lateral femoral circumflex artery and a lateral branch of the popliteal artery (P1). The flap survived completely without serious complications, and the patient was able to walk with crutches 3 months postoperatively. This is the first case report of a free bipedicled DIEP flap for the coverage of a thigh defect in a male patient.

Omentum flap as a salvage procedure in deep sternal wound infection.

INTRODUCTION: Deep sternal wound infections (DSWIs) are rare but devastating complication after median sternotomy following cardiac surgery. Especially in the presence of artificial material or inadequate preliminary muscle flaps, the pedicled omentum flap is due to its immunological properties, the predetermined flap in salvage procedures. METHODS: We treated 14 patients suffering a mediastinitis and open thorax using a pedicled omentoplasty as a salvage procedure because of persisting DSWIs. Omentoplasty was performed in combination with a split skin graft and the wound was closed by a vacuum-assisted therapy for 7 days. The patients' sex and comorbid risk factors supporting DSWIs as well as the postoperative complications were recorded. RESULTS: Retrospective analysis of 14 patients (10 males and four females) after a follow-up time of 24 months was performed. The average age was 75 years (range: 67-83). Heart surgery took place electively in eight cases, in three cases urgently and three for emergency reasons. The preoperative Euro Score was 16 (range 3.51-42.58). We had no flap loss in any patients. The skin graft showed a full take in all patients. Two patients needed revision of an abdominal wound dehiscence after laparotomy and one patient developed hernia in the late outcome. DISCUSSION: The greater omentum flap has, over many years, become an ideal partner in the coverage and treatment of DSWIs. Especially due to its immunologic capacity and amorphous structure, it has the ability to fill up cavities and cover infected artificial material so residual infections can be controlled.

Anatomic study of the vascular perfusion of the sternum and its clinical relevance in deep sternal wound infection.

Introduction: Deep sternal wound infections (DSWI) are a rare but devastating complication after median sternotomy. Minor perfusion in bone and soft tissue, especially after recruiting the internal mammary artery for bypass supports the development of wound infection and nonunion of the sternal bone. The aim of the study was the macroscopic and radiological presentation of the vascular system supplying the sternum, in particular the compensating blood supply routes in the event that the internal mammary artery is no longer available after use as a bypass vessel. Method: This anatomic study was carried out on the anterior chest wall of 7 specimens. The thorax plates of 7 specimens were analyzed macroscopically after microsurgical preparation. Different anatomic preparations were produced using different contrast or form-giving substances. Radiological analysis and three-dimensional reconstructions were performed to show alternative, collateral sternal vessel perfusion under estimation of the loss of the internal thoracic artery due to a bypass. Results: The length of the ITA (internal thoracic artery), measured from the beginning of the first rib to the division into the superior epigastric artery and musculophrenic artery, was an average of 16.3 cm. On average, 18.5 branches were delivered from each artery, 10 medially to the sternum supply, and 8 to the intercostal muscle. Conclusion: Our analysis gives an overview of the macroanatomic vessel system supplying the sternal bone, describing especially a common trunk deriving from the ITA and supplying multiple branches and playing an important role in building a collateral circulation of the sternum. For better evaluation, in vivo CT analysis with contrast media should be performed in patients prior to the operation and directly after the use of the double ITA to demonstrate the change in perfusion of the sternum. In the future, preconditioning of the sternum by coiling the deriving branches could become an option, although patient selection has to be improved and further analysis of the topic performed.

A new in vivo model using a dorsal skinfold chamber to investigate microcirculation and angiogenesis in diabetic wounds.

INTRODUCTION: Diabetes mellitus describes a dysregulation of glucose metabolism due to improper insulin secretion, reduced insulin efficacy or both. It is a well-known fact that diabetic patients are likely to suffer from impaired wound healing, as diabetes strongly affects tissue angiogenesis. Until now, no satisfying in vivo murine model has been established to analyze the dynamics of angiogenesis during diabetic wound healing. To help understand the pathophysiology of diabetes and its effect on angiogenesis, a novel in vivo murine model was established using the skinfold chamber in mice. MATERIALS AND METHODS: Mutant diabetic mice (db; BKS.Cg-m+/+Lepr (db) /J), wildtype mice (dock7Lepr (db) +/+m) and laboratory BALB/c mice were examined. They were kept in single cages with access to laboratory chow with an 12/12 hour day/night circle. Lesions of the panniculus muscle (Ø 2 mm) were created in the center of the transparent window chamber and the subsequent muscular wound healing was then observed for a period of 22 days. Important analytic parameters included vessel diameter, red blood cell velocity, vascular permeability, and leakage of muscle capillaries and post capillary venules. The key parameters were functional capillary density (FCD) and angiogenesis positive area (APA). RESULTS: We established a model which allows high resolution in vivo imaging of functional angiogenesis in diabetic wounds. As expected, db mice showed impaired wound closure (day 22) compared to wounds of BALB/c or WT mice (day 15). FCD was lower in diabetic mice compared to WT and BALB/c during the entire observation period. The dynamics of angiogenesis also decreased in db mice, as reflected by the lowest APA levels. Significant variations in the skin buildup were observed, with the greatest skin depth in db mice. Furthermore, in db mice, the dermis:subcutaneous ratio was highly shifted towards the subcutaneous layers as opposed to WT or BALB/c mice. CONCLUSION: Using this new in vivo model of the skinfold chamber, it was possible to analyze and quantify microangiopathical changes which are essential for a better understanding of the pathophysiology of disturbed wound healing. Research in microcirculation is important to display perfusion in wounds versus healthy tissue. Using our model, we were able to compare wound healing in diabetic and healthy mice. We were also able to objectively analyze perfusion in wound edges and compare microcirculatory parameters. This model may be well suited to augment different therapeutic options.