Preoperative planning using virtual reality and computed tomography angiogram in deep inferior epigastric perforator flap breast reconstruction.

The gold standard for preoperative planning of deep inferior epigastric perforator (DIEP) flap breast reconstruction uses computed tomography angiography (CTA). Virtual reality (VR) circumnavigates the limitations of CTA by reconstructing a fully immersive and interactive 3D representation of the scan. Scans of 44 patients who underwent DIEP flap breast reconstruction were retrospectively reviewed and compared using CTA and VR imaging modalities. The objective of this research was to compare perforators found using VR to the ones identified using conventional CTA. A correlation was found between the imaging modalities for unilateral (R = 0.96 (CI = 0.92, 0.98)) and bilateral (R = 0.93, (CI = 0.83, 0.97)) DIEP flap surgeries when comparing perforator location related to the umbilicus. Multivariable ordinal logistic regression found that higher intramuscular course length (IMC) is associated with the number of perforators found per side (OR = 1.79 (CI = 1.24, 2.6)), and medial location (OR = 2.85 (CI = 1.38, 5.87)). Larger vessel caliber (VC) is associated with shorter IMC (T2 vs. T3, OR = 3.34 (CI = 1.49, 7.49)), and branching in adipose tissue (AB) is associated with higher VC (T1 vs. T3, OR = 0.02 (CI = 0.007, 0.08); T2 vs. T3, OR = 0.24 (CI = 0.11, 0.55)). Overall, preoperative planning using VR was easy to use, safe, more intuitive, and provided in a time-efficient manner, more information about perforant characteristics. VR can improve the surgeon's decision accuracy, relating to the best perforators for harvesting, in a shorter time period.

Cartilage-Sparing Otoplasty: A New Approach.

SUMMARY: Ear protrusion is the primary indication for otoplasty. Many methods have been developed for addressing this defect, based on cartilage-scoring and excision and suture-fixation techniques. Disadvantages include irreversible distortion of the anatomy, irregularities, or overcorrection, or forward bulging of the conchal bowl. One of the most common long-term sequelae of otoplasty is an unsatisfactory result. A novel, cartilage-sparing, suture-based technique has been developed that aims to minimize the risk of complications and provide a natural-appearing aesthetic result. The method is based on two to three key sutures that shape the concha into the desired natural appearance while preventing a conchal bulge, which otherwise could appear if no cartilage is removed. Furthermore, these sutures support the neo-antihelix created by four further sutures anchored to the mastoid fascia, thus achieving the two main goals of otoplasty. The sparing of cartilaginous tissue means that the procedure is reversible if needed. In addition, permanent postoperative stigmata, pathologic scarring, and anatomical deformity can be avoided. This technique was used on 91 ears in 2020 and 2021, with only one ear (1.1%) requiring revision. Rates of complications or recurrence were low. The presented technique appears to be a rapid and safe method for treating the prominent ear deformity, providing aesthetically pleasing results.

Surgical site infection in reconstructive and aesthetic breast surgery: A single center retrospective analysis of the association between healthcare workers and infections.

BACKGROUND: Reconstructive and aesthetic breast surgeries are frequently performed procedures, and the consequences of a postoperative infection are devastating both for the patient and the healthcare (HC) system. Over the years, there has been heightened interest in the physical and mental well-being of physicians and HC workers. Little is known about the relationship between HC workers and surgical site infections (SSI), and whether HC workers are at an increased risk for SSI. The aim of this study was to investigate whether women working in the HC system have an increased risk for SSI following reconstructive and aesthetic breast surgery. MATERIALS AND METHODS: We conducted a retrospective analysis of all patients who underwent aesthetic and reconstructive breast surgery at our institution between the years 2013-2020. Women who were recognized as HC workers were analyzed in a separate group and compared to those who were not. RESULTS: Records of 378 patients were reviewed, of whom 53 (14%) were identified as HC workers. The overall infection rate was 17.4%. HC workers manifested a higher infection rate than the other group (32% vs. 15.1%, p<0.05) and a significantly higher relative risk for SSI (RR 2.12, p<0.01). CONCLUSIONS: Women working in the HC system may have an increased risk of developing postoperative infectious complications following aesthetic and reconstructive breast-related surgery. Further research is needed to corroborate these findings and elucidate the causes.

Techniques and Innovations in Flap Engineering: A Review.

Currently, the gold standard for complex defect reconstruction is autologous tissue flaps, with vascularized composite allografts as its highest level. Good clinical results are obtained despite considerable obstacles, such as limited donor sites, donor site morbidity, and complex operations. Researchers in the field of tissue engineering are trying to generate novel tissue flaps requiring small or no donor site sacrifice. At the base of existing technologies is the tissue's potential for regeneration and neovascularization. Methods: A review was conducted identifying relevant published articles in PubMed on the subject of flap engineering, with the focus on plastic surgery. This review article surveys contemporary technologies in flap engineering, including cell sheet technology, prefabricated flaps, and tissue engineering chambers. Conclusions: Some of the described procedures, though not yet ready for clinical use, are certainly ready for trial in large animal models and even human studies. Tissue engineering is a promising field for the handling of large and complex tissue defects.

In vivo study of the efficacy of bupivacaine-eluting novel soy protein wound dressings in a rat burn model.

Dealing with wound related pain is an integral part of treatment. Systemic administration of analgesic and anesthetic agents is a common solution for providing pain relief to patients but comes at a risk of severe side effects as well as addiction. To overcome these issues, research efforts were madeto provide a platform for local controlled release of pain killers. We have developed a bilayer soy protein-based wound dressing for the controlled local release of bupivacaine to the wound site. The combination of a dense and a porous layer provides a platform for cell growth and proliferation as well as physical protection to the wound site. The current study focuses on the in vitro bupivacaine release profile from the dressing and the corresponding in vivo results of pain levels in a second-degree burn model on rats. The Rat Grimace Scale method and the Von Frey filaments method were used to quantify both, spontaneous pain and mechanically induced pain. A high burst release of 61.8 ± 1.9% of the loaded drug was obtained during the initial hour, followed by a slower release rate during the following day. The animal trials show that the RGS scores of the bupivacaine-treated group were significantly lower than these of the untreated group, proving a decrease of 51-68% in pain levels during days 1-3 after burn. Hence, successful pain reduction of spontaneous pain as well as mechanically induced pain, for at least three days after burn was achieved. It is concluded that our novel bupivacaine eluting soy protein wound dressings are a promising new concept in the field of local controlled drug release for pain management.

Advances in the Use of Electrospun Nanofibrous Polymeric Matrix for Dermal Healing at the Donor Site After the Split-Thickness Skin Graft Excision: A Prospective, Randomized, Controlled, Open-Label, Multicenter Study.

Dressings used to manage donor site wounds (DSWs) have up to 40% of patients experiencing complications that may cause suboptimal scarring. We evaluated the efficacy and safety of a portable electrospun nanofibrous matrix that provides contactless management of DSWs compared with standard dressing techniques. This study included adult patients who underwent an excised split-thickness skin graft (STSG) with a DSW area of 10 to 200 cm2. Patients were allocated into two groups; ie, the nanofiber group managed with a nanofibrous polymer-based matrix, and the control group managed using the standard of care such as Jelonet® or Biatain® Ibu dressing. Primary outcomes were postoperative dermal healing efficacy assessed by Draize scores. The time to complete re-epithelialization was also recorded. Secondary outcomes included postoperative adverse events, pain, and infections during the first 21 days and extended 12-month follow-up. The itching and scarring were recorded during the extended follow-up (months 1, 3, 6, 9, and 12) using Numerical-Analogue-Score and Vancouver scores, respectively. The nanofiber and control groups included 21 and 20 patients, respectively. The Draize dermal irritation scores were significantly lower in the nanofiber vs control group (Z = -2.509; P = .028) on the first postoperative day but became similar afterward (Z ≥ -1.62; P ≥ .198). In addition, the average time to re-epithelialization was similar in the nanofiber (17.9 ± 4.4 days) and control group (18.3 ± 4.5 days; Z = -0.299; P = .764), so were postoperative adverse events, pain, and infection incidence, itching and scarring. The safety and efficacy of electrospun nanofibrous matrix are similar to standard wound care allowing its use as an alternative donor site dressing following the STSG excision.

Microcomputed Tomography-Based Analysis of Neovascularization within Bioengineered Vascularized Tissues.

In the field of tissue engineering, evaluating newly formed vascular networks is considered a fundamental step in deciphering the processes underlying tissue development. Several common modalities exist to study vessel network formation and function. However, a proper methodology that allows through three-dimensional visualization of neovessels in a reproducible manner is required. Here, we describe in-depth exploration, visualization, and analysis of vessels within newly formed tissues by utilizing a contrast agent perfusion protocol and high-resolution microcomputed tomography. Bioengineered constructs consisting of porous, biocompatible, and biodegradable scaffolds are loaded with cocultures of adipose-derived microvascular endothelial cells (HAMECs) and dental pulp stem cells (DPSCs) and implanted in a rat femoral bundle model. After 14 days of in vivo maturation, we performed the optimized perfusion protocol to allow host penetrating vascular visualization and assessment within neotissues. Following high-resolution microCT scanning of DPSC:HAMEC explants, we performed the volumetric and spatial analysis of neovasculature. Eventually, the process was repeated with a previously published coculture system for prevascularization based on adipose-derived mesenchymal stromal cells (MSCs) and HAMECs. Overall, our approach allows a comprehensive understanding of vessel organization during engraftment and development of neotissues.

Bromelain-based enzymatic debridement of chronic wounds: Results of a multicentre randomized controlled trial.

Chronic wounds are estimated to affect over 6 million people annually in the United States with an estimated annual cost of $25 billion. Debridement represents a key step in their management and is considered a basic necessity to induce the functional process of tissue repair. However, there is an unmet need for an efficient rapid acting non-surgical debridement agent. Bromelain-based enzymatic debridement has been proven to provide an effective, selective and safe non-surgical debridement in deep burns. EscharEx (MediWound Ltd, Yavne, Israel), is a bromelain-based enzymatic debridement agent currently in development for chronic wounds. The aim of this study was to assess its safety and efficacy in chronic wounds. Seventy-three patients suffering from a lower extremity ulcer of diabetic/venous insufficiency/post-surgical/traumatic aetiology were enrolled in a multicentre, assessor blinded, randomized controlled trial. Patients were randomized to topical treatment by either EscharEx or its gel vehicle for up to 10 daily 4 hour applications, and then continued follow-up for up to 6 months. The EscharEx arm achieved a significantly higher incidence of complete debridement compared to the gel vehicle arm; 55 versus 29% (p = .047), thus meeting the primary endpoint of this study. The EscharEx and gel vehicle arms achieved similar reductions in wound area, non-viable tissue area and wound healing scores during the debridement period. There were no significant differences between the arms in the incidence of complete wound closure (41% in the EsxcharEx arm vs. 53% in the gel vehicle arm) and in the mean time to complete wound closure (70.0 ± 32.8 days in the EsxcharEx arm vs. 65.7 ± 38.4 days in gel vehicle arm). There were no significant safety issues and EscharEx demonstrated a favourable benefit to risk profile.

Free Nipple Grafting and Nipple Sharing in Autologous Breast Reconstruction after Mastectomy.

Nipple sparing mastectomy is gaining popularity in recent years, as it provides superior aesthetic results and has a positive impact on the psychological well-being of patients. However, patients with macromastia and high grade ptosis are not good candidates for nipple sparing mastectomy due to a high risk for nipple necrosis; for these patients, the free nipple grafting (FNG) is an excellent option following autologous reconstruction. We herein present our experience with FNG for women with large and ptotic breasts undergoing mastectomy and autologous reconstruction. We also present the option of splitting a single nipple-areolar complex to provide 2 grafts for bilateral nipple reconstruction. This retrospective study is based on data collected between 2014 and 2019 at a single institution. We report on 7 patients (13 grafts): 5 patients underwent FNG (4 bilateral, 1 unilateral) and 2 patients had a single nipple split into 2 parts to create 2 nipple-areolar complexes. Of the 13 grafts, 9 had complete take, 3 had almost complete take, and only 1 graft was lost. Overall patient satisfaction from the procedure was high. The use of FNG is an excellent reconstructive option, as it preserves the patient's own nipple in terms of color, shape, and texture. The procedure can be executed as part of a direct single-staged reconstruction for patients who are at a high risk for nipple necrosis.

[DOES NEOADJUVANT CHEMOTHERAPY AFFECT THE IMMEDIATE POSTOPERATIVE COMPLICATION RATE AFTER BREAST RECONSTRUCTION?]

BACKGROUND: Neoadjuvant chemotherapy (NAC) before breast cancer surgery is safe and effective. By reducing the tumor burden, women can achieve complete resections with less extensive operations. Both surgeons and patients share concerns that NAC increases the risk for infection after immediate breast reconstruction, due to its effect on the immune system and the relatively short duration between chemotherapy and surgery. While breast reconstruction plays an increasingly significant role in the treatment of breast cancer, little has been written about the effect of NAC and its impact on post-operative complications. METHODS: We identified 158 patients (205 breasts) who underwent surgery for breast cancer with immediate reconstruction between the years 2013-2017 at the Kaplan Medical Center. Using univariate and multivariate statistics, we compared our patient characteristics according to our main predictor of interest: receiving NAC. We focused on the immediate post-operative complications: infection, skin necrosis, wound dehiscence, hematoma, seroma and implant explantation. RESULTS: Fifty-two patients received NAC and 106 did not. The neoadjuvant group was found to be younger (45 years old vs. 51, P<0.05). The overall complication rate was 30.3%, with a trend towards a lower complication rate in the NAC group, though not statistically significant (23% vs. 34% P=0.2). The overall infection rate was 8.8%, again with a trend towards a lower infection rate among the NAC group (3.8% vs. 11.3% P=0.12). Mastectomy (P=0.02), implant reconstruction (P=0.05) and diabetes (P<0.05) were associated with a higher complication rate. CONCLUSIONS: Our data indicates that NAC is not associated with an increased rate of immediate post-operative complications in women undergoing breast surgery and reconstruction. Therefore, receiving NAC should not be considered a reason to avoid immediate breast reconstruction.

Tumor-to-Nipple Distance in Selecting Patients for Nipple-sparing Mastectomy.

Nipple-sparing mastectomy (NSM) is a valid option for carefully selected cases. Oncologic guidelines have not been established, but proximity of the tumor to the nipple, tumor size, lymph node involvement, and neoadjuvant chemotherapy have been suggested as contraindications to nipple preservation. This study describes our experience with NSM in relation to these factors, in particular distance of tumor from the nipple, to help establish evidence-based guidelines for NSM. METHOD: All NSM procedures performed at our institution between 2014 and 2018 were reviewed. The tumor-to-nipple distance was measured for each patient using mammography, ultrasound, or magnetic resonance imaging. All patients underwent a frozen section (FS) biopsy of the base of the nipple during surgery, and if cancer was detected, the procedure was converted to a skin-sparing mastectomy. Patients were followed for postoperative complications and cancer recurrence. RESULTS: Sixty-eight patients (98 breasts) underwent NSM with immediate reconstruction. Fifty-three patients (78%) underwent the procedure for breast cancer. Nipple involvement was detected on FS in 1 patient and on permanent pathology after a negative FS in 1 patient. Forty-three percent of our patients had a tumor-to-nipple distance of ≤2 cm. During a mean follow-up of 32.5 months (±19.4 months), no locoregional recurrences were observed; however, distant metastasis occurred in 3 patients. CONCLUSIONS: When histologic examination from the base of the nipple is negative (either by FS or permanent pathology), NSM can be considered oncologically safe. Lack of nipple involvement by preoperative clinical and imaging assessment and intraoperative FS is sufficient to classify patients as suitable for NSM.

Engineering vascularized flaps using adipose-derived microvascular endothelial cells and mesenchymal stem cells.

Human adipose-derived microvascular endothelial cells (HAMEC) and mesenchymal stem cells (MSC) have been shown to bear angiogenic and vasculogenic capabilities. We hypothesize that co-culturing HAMEC:MSC on a porous biodegradable scaffold in vitro, later implanted as a graft around femoral blood vessels in a rat, will result in its vascularization by host vessels, creating a functional vascular flap that can effectively treat a range of large full-thickness soft tissue defects. HAMEC were co-cultured with MSC on polymeric three-dimensional porous constructs. Grafts were then implanted around the femoral vessels of a rat. To ensure vessel sprouting from the main femoral vessels, grafts were pre-isolated from the surrounding tissue. Graft vascularization was monitored to confirm full vascularization before flap transfer. Flaps were then transferred to treat both abdominal wall and exposed bone and tendon of an ankle defects. Flaps were analysed to determine vascular properties in terms of maturity, functionality and survival of implanted cells. Findings show that pre-isolated grafts bearing the HAMEC:MSC combination promoted formation of highly vascularized flaps, which were better integrated in both defect models. The results of this study show the essentiality of a specific adipose-derived cell combination in successful graft vascularization and integration, two processes crucial for flap survival. Copyright © 2017 John Wiley & Sons, Ltd.

[REVIEW OF COMMON PATHOGENS IN THE BONE AND BLOOD CULTURES AND ANTIBIOTIC TREATMENT IN PATIENTS WITH STERNAL OSTEOMYELITIS].

AIMS: This study concentrates on microbiological data collection of deep sternal wounds to delineate early and correct antibiotic therapy. BACKGROUND: Deep sternal wound infection, mediastinitis and sternal osteomyelitis are devastating and life-threatening complications of median-sternotomy incisions after cardiac surgical procedures. The incidence of surgical wound infection in sternotomies should be similar to that in any clean surgical procedure (i.e. approximately 2%). Nonetheless, the infection rates are higher among heart disease patients, due to the fact that these patients are burdened with a high number of risk factors in comparison with the general population. RESULTS: In line with other publications, the most commonly cultured organism from deep sternal wound and blood cultures was found to be Staphylococcus. In comparison, the most commonly cultured Gram-negative organisms were Pseudomonas and all gram-negative organisms combined together represented approximately 50% of all cultures. Three dominant organisms were isolated from wound and blood cultures: Staphylococcus, Pseudomonas and Acinetobacter. We found that 40% of blood cultures were identical to prior wound cultures, in comparison to 30% of bone cultures. Furthermore, 20% of the organisms isolated from the wound and 13% of the organisms isolated from the bone later on cross over to involve the blood. CONCLUSIONS: Empiric antibiotic regimen should be broad spectrum and cover both gram-positive as well as gramnegative organisms. We demonstrate that antibiotic regimen during sepsis may rely partially on preliminary wound cultures. Furthermore, antibiotic treatment for a relatively short period of two weeks is adequate, alongside thorough surgical revision with debridement of all foreign bodies, and reconstruction with vascularized soft tissue flap (pectoral major).

Topical Erythropoietin Treatment Accelerates the Healing of Cutaneous Burn Wounds in Diabetic Pigs Through an Aquaporin-3-Dependent Mechanism.

We have previously reported that the topical application of erythropoietin (EPO) to cutaneous wounds in rats and mice with experimentally induced diabetes accelerates their healing by stimulating angiogenesis, reepithelialization, and collagen deposition, and by suppressing the inflammatory response and apoptosis. Aquaporins (AQPs) are integral membrane proteins whose function is to regulate intracellular fluid hemostasis by enabling the transport of water and glycerol. AQP3 is the AQP that is expressed in the skin where it facilitates cell migration and proliferation and re-epithelialization during wound healing. In this report, we provide the results of an investigation that examined the contribution of AQP3 to the mechanism of EPO action on the healing of burn wounds in the skin of pigs with experimentally induced type 1 diabetes. We found that topical EPO treatment of the burns accelerated their healing through an AQP3-dependent mechanism that activates angiogenesis, triggers collagen and hyaluronic acid synthesis and the formation of the extracellular matrix (ECM), and stimulates reepithelialization by keratinocytes. We also found that incorporating fibronectin, a crucial constituent of the ECM, into the topical EPO-containing gel, can potentiate the accelerating action of EPO on the healing of the burn injury.

[REVIEW OF 30 YEARS OF RESEARCH AND DEVELOPMENT OF AN ENZYMATIC DEBRIDEMENT AGENT FOR BURNS].

INTRODUCTION: Early removal of burn eschar is a cornerstone of burn care. The most commonly practiced eschar removal technique for deep burns in modern burn care is surgical debridement but this technique is associated with surgical burden and leads to unnecessary excision of viable tissue. GOALS: To review 30 years of research and development of an enzymatic debridement agent for burns. METHODS: Studies performed during the last 30 years are reviewed in this manuscript. RESULTS: Patients who underwent enzymatic debridement had a significantly shorter time to complete debridement, the surgical burden was significantly lower, hand burns did not necessitate escharotomy, and the long term results were favorable. DISCUSSION: Early enzymatic debridement leads to an efficient debridement, preservation of viable tissue, a reduction in surgical burden and favorable long term results. CONCLUSION: We believe early enzymatic debridement will lead to better care for burn victims and perhaps, even to a paradigm shift in the treatment of burns.

Engineered Vascularized Muscle Flap.

One of the main factors limiting the thickness of a tissue construct and its consequential viability and applicability in vivo, is the control of oxygen supply to the cell microenvironment, as passive diffusion is limited to a very thin layer. Although various materials have been described to restore the integrity of full-thickness defects of the abdominal wall, no material has yet proved to be optimal, due to low graft vascularization, tissue rejection, infection, or inadequate mechanical properties. This protocol describes a means of engineering a fully vascularized flap, with a thickness relevant for muscle tissue reconstruction. Cell-embedded poly L-lactic acid/poly lactic-co-glycolic acid constructs are implanted around the mouse femoral artery and vein and maintained in vivo for a period of one or two weeks. The vascularized graft is then transferred as a flap towards a full thickness defect made in the abdomen. This technique replaces the need for autologous tissue sacrifications and may enable the use of in vitro engineered vascularized flaps in many surgical applications.

Adipose-derived endothelial and mesenchymal stem cells enhance vascular network formation on three-dimensional constructs in vitro.

BACKGROUND: Adipose-derived mesenchymal stem cells (MSCs) have been gaining fame mainly due to their vast clinical potential, simple isolation methods and minimal donor site morbidity. Adipose-derived MSCs and microvascular endothelial cells have been shown to bear angiogenic and vasculogenic capabilities. We hypothesized that co-culture of human adipose-derived MSCs with human adipose-derived microvascular endothelial cells (HAMECs) will serve as an effective cell pair to induce angiogenesis and vessel-like network formation in three-dimensional scaffolds in vitro. METHODS: HAMECs or human umbilical vein endothelial cells (HUVECs) were co-cultured on scaffolds with either MSCs or human neonatal dermal fibroblasts. Cells were immunofluorescently stained within the scaffolds at different time points post-seeding. Various analyses were performed to determine vessel length, complexity and degree of maturity. RESULTS: The HAMEC:MSC combination yielded the most organized and complex vascular elements within scaffolds, and in the shortest period of time, when compared to the other tested cell combinations. These differences were manifested by higher network complexity, more tube alignment and higher α-smooth muscle actin expression. Moreover, these generated microvessels further matured and developed during the 14-day incubation period within the three-dimensional microenvironment. CONCLUSIONS: These data demonstrate optimal vascular network formation upon co-culture of microvascular endothelial cells and adipose-derived MSCs in vitro and constitute a significant step in appreciation of the potential of microvascular endothelial cells and MSCs in different tissue engineering applications that can also be advantageous in in vivo studies.