The Unhoused Burn Population: An Alarming Increase of Leaving Against Medical Advice.

Unhoused burn patients (UBP) have historically been more likely to leave against medical advice (AMA) and suffer worse health outcomes than the general population. The coronavirus disease 2019 (COVID-19) pandemic created a major strain on the healthcare system, resulting in worse overall health outcomes for burn patients. We sought to investigate how COVID-19 impacted treatment for UBP, specifically the rate of leaving AMA. We conducted a retrospective chart analysis of patients admitted to a regional burn center between June 2015 and January 2023. March 1, 2020, was used as a cut point to separate the cohorts into patients seen pre-COVID-19 (p-CV) and during COVID-19 (CV). Outcomes included leaving treatment AMA and readmission within 30 days. 385 patients met criteria for being unhoused and were included in our analytic sample, of which 199 were in the p-CV cohort and 186 in the CV cohort. UBP were significantly more likely to leave AMA during CV compared to p-CV (22.6% vs. 7.5%, p<0.001). Housed burn patients did not experience an increase in discharges AMA during this time period. The COVID-19 pandemic resulted in an increase in discharges AMA among unhoused patients only. While the etiology is unclear, our findings suggest that this vulnerable patient population is receiving inadequate care post-COVID. Future research should determine the driving force behind these increases and identify early interventions to mitigate them.

Endoscopic Tissue Expander Implantation in Post-Burn Reconstruction: A Review of the Literature.

BACKGROUND: Tissue expansion generates new tissue that can be used in post-burn reconstruction. Expanders are placed through small incisions, requiring difficult and sometimes blind dissection to prepare an adequate pocket. Recently, the use of endoscopy to assist in expander placement has been described, which may improve intraoperative visualization and allow for a smaller incision. In this review, we summarize the existing literature of endoscopic tissue expander (TE) placement in post-burn reconstruction and highlight areas for future research. METHODS: The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines were utilized to conduct this review. The following databases were queried for the initial search of relevant articles: PubMed, Embase, Scopus, Cochrane, and Web of Science. The data was assessed qualitatively due to the heterogeneity in reporting between the studies. RESULTS: Our literature query yielded 1,023 studies. Sixteen manuscripts underwent full-text review, and seven met inclusion criteria. All studies demonstrated that the endoscopic approach led to successful tissue expansion. Four articles performed a comparative analysis between the open and endoscopic approach, all of which found a significant reduction in complications like seroma, hematoma formation, and device exposure with endoscopic TE implantation. Two studies demonstrated that the use of endoscopy significantly reduced operative time and length of stay. CONCLUSION: Endoscopy is a safe and effective tool in tissue expansion for post-burn reconstruction. Further prospective research should include evaluating the cost-benefit of this approach and long-term outcomes for patients who have undergone endoscopic-assisted tissue expander placement.

Impact of volume and rate of milk delivery on coordination of respiration and swallowing in infant pigs.

The coordination of respiration and swallowing is a life-critical function in infants. Varying volume and rate of milk delivery changes swallowing frequency and bolus volume but any impact on swallow-respiration coordination is unknown. Five infant pigs were filmed with simultaneous high speed videofluoroscopy and plethysmography while feeding from an automatic system delivering milk across a range of volumes and frequencies. Swallow inspiration delay, respiratory cycle duration, and distribution of inspiratory and expiratory swallows were calculated. At constant volume, there were more inspiratory phase swallows when frequency increased. At high constant frequency, increasing volume changed swallow-respiration coordination patterns, with increased occurrence of inspiratory phase swallows. Respiratory cycle duration did not change in response to changes in oral milk delivery. These results suggest that the observed pattern of expiratory swallowing in infants is achieved primarily by regulation of milk intake, not modulation of respiratory patterns by oral sensation.

Exploring the interaction of viscosity and nipple design on feeding performance in an infant pig model.

Infant feeding behaviors are modulated via sensorimotor feedback, such that sensory perturbations can significantly impact performance. Properties of the nipple and milk (e.g., nipple hole size and viscosity) are critical sources of sensory information. However, the direct effects of varying milk and nipple properties on infant motor output and the subsequent changes in feeding performance are poorly understood. In this study, we use an infant pig model to explore the interaction between nipple hole size and milk viscosity. Using high-speed videofluoroscopy and electromyography, we measured key performance metrics including sucks per swallow and suck duration, then synchronized these data with the onset and offset of activity of jaw opening and closing muscles. The combination of a small nipple hole and thick milk resulted in negative effects on both suck and swallow performance, with reduced feeding efficiency compared to the other treatments. It also appears that this combination of viscosity and hole size disrupts the coordination between correlates of tongue and jaw movements. We did not see a difference in feeding efficiency between viscosities when infants fed on the large-hole nipple, which may be the result of non-Newtonian fluid mechanics. Our results emphasize the importance of considering both fluid and nipple properties when considering alterations to an infant's feeding system.

Nipple properties affect sensorimotor integration during bottle feeding in an infant pig model.

Infant feeding is a critical neurological milestone in development defined by the coordination of muscles, peripheral nerves, and brainstem nuclei. In infants, milk flow rate is often limited to improve feeding performance without treating the underlying deficiencies in the sucking and swallowing processes. Modification of the neuromotor response via sensory information from the nipple during bottle feeding is an unexplored avenue for physiology-based interventions. In this study, we assessed how differences in nipple hole size and nipple stiffness affect sucking muscle activation and subsequent movement. We fabricated four bottle nipples of varying hole size and stiffness to determine how variation in nipple properties affects the sucking behavior of infant pigs. Our results demonstrate that sensory information from the nipple affects sucking motor output. Nipple hole sizes and stiffnesses with a larger milk flow rate resulted in greater muscle activity and kinematic movement. Additionally, our results suggest that sensorimotor interventions are better directed toward modulating tongue function rather than the mandible movements due to a greater response to sensory information. Understanding how sensory information influences infant feeding is instrumental in promoting effective infant feeding.

Psychiatric Illness and Substance Abuse: Unaddressed Factors in Burn Injury.

Patients with psychiatric illness and substance use comorbidities have high rates of burn injuries and experience prolonged hospital admissions. This retrospective chart review characterizes this marginalized population's inpatient burn care and examines post-discharge outcomes compared to burn patients without psychiatric or substance use comorbidities treated at our center. Patients admitted to a single burn center from January 1, 2018 to June 1, 2022 were included. Patient demographics, history of psychiatric disorders, treatment course, and post-discharge outcomes were collected. A total of 1660 patients were included in this study, of which 91 (6%) patients were diagnosed for psychiatric comorbidity and/or substance use comorbidity on admission for burn care. In this cohort of 91 patients with psychiatric and/or substance use comorbidities, the majority of patients were undomiciled (66%) and male (67%). In this cohort, 66 (72%) patients reported recent history or had positive urine toxicology results for illicit substances on admission. In this cohort, a total of 25 (28%) patients had psychiatric comorbidity at the time of burn injury or admission and 69 (76%) patients received inpatient psychiatric care, with 31 (46%) patients requiring psychiatric holds. After discharge, the readmission rate within 1 year of patients with psychiatric and/or substance use comorbidity was over four times greater than that of patients without psychiatric and/or substance use comorbidity. The most common causes of readmission were subsequent mental health crisis (40%) and inability to perform burn care (32%). Our study presents strategies to improve burn care for this marginalized and high-risk population.

Burn Patient Insurance Status Influences Hospital Discharge Disposition and Utilization of Postdischarge Outpatient Care.

Postdischarge services, such as outpatient wound care, may affect long-term health outcomes and postrecovery quality-of-life. Access to these services may vary according to insurance status and ability to cover out-of-pocket expenses. Our objective was to compare discharge location between burn patients who were uninsured, publicly insured, and privately insured at the time of their burn unit admissions. A retrospective review from July 1, 2015 to November 1, 2019 was performed at an American Burn Association-verified burn center. All admitted burn patients 18 years and older were identified and categorized according to insurance payer type. The primary outcome was discharge location, and secondary outcomes included readmission and outpatient burn care attendance. In total, 284 uninsured, 565 publicly insured, and 293 privately insured patients were identified. There were no significant differences in TBSA (P = .3), inhalation injury (P = .3), intensive care unit days (P = .09), or need for skin grafting (P = .1) between the three groups. For primary outcome, uninsured patients were more likely to be discharged without ancillary services (P < .0001) compared to both publicly and privately insured. Publicly insured patients were more likely to receive skilled nursing care (P = .0007). Privately insured patients were more likely to receive homecare (P = .0005) or transfer for ongoing inpatient care (P < .0001). There was no difference in burn unit readmission rates (P = .5). The uninsured were more likely to follow up with outpatient burn clinic after discharge (P = .004). Uninsured patients were less likely to receive postdischarge resources. Uninsured patients received fewer postdischarge wound care resources which could result in suboptimal long-term results, and diminished return to preinjury functional status. Given the impact of insurance status on discharge location and resources, efforts to increase access for uninsured patients to postdischarge resources will ensure greater healthcare equity and improve quality of comprehensive care regardless of insurance status.

The effect of stiffness and hole size on nipple compression in infant suckling.

During infant feeding, the nipple is an important source of sensory information that affects motor outputs, including ones dealing with compression of the nipple, suction, milk bolus movement, and swallowing. Despite known differences in behavior across commercially available nipples, little is known about the in vivo effects of nipple property variation. Here we quantify the effect of differences in nipple stiffness and hole size on an easily measured metric representing infant feeding behavior: nipple compression. We bottle-fed 7-day old infant pigs (n = 6) on four custom fabricated silicone nipples. We recorded live X-ray fluoroscopic imaging data of feeding on nipples of two levels of hardness/stiffness and two hole sizes. We tested for differences in nipple compression at the nipple's maximum compression across different nipple types using a mixed model analysis of variance. Stiffer nipples and those with smaller holes were compressed less than compliant nipples and nipples with larger holes (p < 0.001). We also estimated the force applied on the nipple during feeding and found that more force was applied to the compliant nipple with disproportionately larger strains. Our results suggest that infant pigs' nipple compression depends on material type and hole size, which is likely detected by the infant pigs' initial assessment of compressibility and flow. By isolating nipple properties, we demonstrated a relationship between properties and suckling behavior. Our results suggest that sensory information affects feeding behaviors and may also inform clinical treatment of poor feeding performance.

Prolymphangiogenic Effects of 9-cis Retinoic Acid Are Enhanced at Sites of Lymphatic Injury and Dependent on Treatment Duration in Experimental Postsurgical Lymphedema.

Background: Patients undergoing surgical treatment for solid tumors are at risk for development of secondary lymphedema due to intraoperative lymphatic vessel injury. The damaged lymphatic vessels fail to adequately regenerate and lymphatic obstruction leads to fluid and protein accumulation in the interstitial space and chronic lymphedema develops as a result. There are currently no effective pharmacological agents that reduce the risk of developing lymphedema or treat pre-existing lymphedema, and management is largely palliative. The present study investigated the efficacy of various 9-cis retinoic acid (9-cis RA) dosing strategies in reducing postsurgical lymphedema by utilizing a well-established mouse tail lymphedema model. Methods and Results: Short-duration treatment with 9-cis RA did not demonstrate a significant reduction in postoperative tail volume, nor an improvement in lymphatic clearance. However, long-term treatment with 9-cis RA resulted in decreased overall tail volume, dermal thickness, and epidermal thickness, with an associated increase in functional lymphatic clearance and lymphatic vessel density, assessed by LYVE-1 immunostaining, compared with control. These effects were seen at the site of lymphatic injury, with no significant changes observed in uninjured sites such as ear skin and the diaphragm. Conclusions: Given the reported results indicating that 9-cis RA is a potent promoter of lymphangiogenesis and improved lymphatic clearance at sites of lymphatic injury, investigation of postoperative 9-cis RA administration to patients at high risk of developing lymphedema may demonstrate positive efficacy and reduced rates of postsurgical lymphedema.

Risk Factors for Wound Complications After Soft Tissue Sarcoma Resection.

ABSTRACT: Soft tissue sarcomas are a heterogenous group of malignant tumors that represent approximately 1% of adult malignancies. Although these tumors occur throughout the body, the majority involved the lower extremity. Management may involve amputation but more commonly often includes wide local resection by an oncologic surgeon and involvement of a plastic surgeon for reconstruction of larger and more complex defects. Postoperative wound complications are challenging for the surgeon and patient but also impact management of adjuvant chemotherapy and radiation therapy. To explore risk factors for wound complications, we reviewed our single-institution experience of lower-extremity soft tissue sarcomas from April 2009 to September 2016. We identified 127 patients for retrospective review and analysis. The proportion of patients with wound complications in the cohort was 43.3%. Most notably, compared with patients without wound complications, patients with wound complications had a higher proportion of immediate reconstruction (34.5% vs 15.3%; P = 0.05) and a marginally higher proportion who received neoadjuvant radiation (30.9% vs 16.7%; P = 0.06).

The Impact of No Next of Kin Decision Makers on End-of-Life Care.

For critically ill burn patients without a next of kin, the medical team is tasked with becoming the surrogate decision maker. This poses ethical and legal challenges for burn providers. Despite this frequent problem, there has been no investigation of how the presence of a next of kin affects treatment in burn patients. To evaluate this relationship, a retrospective chart review was performed on a cohort of patients who died during the acute phase of their burn care. Variables collected included age, gender, length of stay, total body surface area, course of treatment, and presence of a next of kin. In total, 67 patients met the inclusion criteria. Of these patients, 14 (21%) did not have a next of kin involved in medical decisions. Patients without a next of kin were significantly younger (P = .02), more likely to be homeless (P < .01), had higher total body surface area burns (P = .008), had shorter length of stay (P < .001), and were five times less likely to receive comfort care (P = .01). Differences in gender and ethnicity were not statistically significant. We report that patients without a next of kin present to participate in medical decisions are transitioned to comfort care less often despite having a higher burden of injury. This disparity in standard of care demonstrates a need for a cultural shift in burn care to prevent the suffering of these marginalized patients. Burn providers should be empowered to reduce suffering when no decision maker is present.

Characteristics of Upper Extremity Recovery in Acute Flaccid Myelitis: A Case Series.

BACKGROUND: Clinical characteristics and timing associated with nonsurgical recovery of upper extremity function in acute flaccid myelitis are unknown. METHODS: A single-institution retrospective case series was analyzed to describe clinical features of acute flaccid myelitis diagnosed between October of 2013 and December of 2016. Patients were consecutively sampled children with a diagnosis of acute flaccid myelitis who were referred to a hand surgeon. Patient factors and initial severity of paralysis were compared with upper extremity muscle strength outcomes using the Medical Research Council scale every 3 months up to 18 months after onset. RESULTS: Twenty-two patients with acute flaccid myelitis (aged 2 to 16 years) were studied. Proximal upper extremity musculature was more frequently and severely affected, with 56 percent of patients affected bilaterally. Functional recovery of all muscle groups (≥M3) in an individual limb was observed in 43 percent of upper extremities within 3 months. Additional complete limb recovery to greater than or equal to M3 after 3 months was rarely observed. Extraplexal paralysis, including spinal accessory (72 percent), glossopharyngeal/hypoglossal (28 percent), lower extremity (28 percent), facial (22 percent), and phrenic nerves (17 percent), was correlated with greater severity of upper extremity paralysis and decreased spontaneous recovery. There was no correlation between severity of paralysis or recovery and patient characteristics, including age, sex, comorbidities, prodromal symptoms, or time to paralysis. CONCLUSIONS: Spontaneous functional limb recovery, if present, occurred early, within 3 months of the onset of paralysis. The authors recommend that patients without signs of early recovery warrant consideration for early surgical intervention and referral to a hand surgeon or other specialist in peripheral nerve injury. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.

Patient Characteristics Associated with Free Nipple Graft Reduction Mammoplasty.

PURPOSE: Surgical approaches for reduction mammoplasty most commonly incorporate a parenchymal vascular pedicle. For patients with larger breasts where pedicle viability may be compromised due to excessive length, the free nipple graft (FNG) technique provides a safe alternative. Criteria for whether a patient should undergo a FNG remains controversial due to variable reports in the literature with small sample sizes and inherent surgeon-dependent bias. To address this, we sought to investigate perioperative factors associated with performing FNGs at our institution in order to better elucidate specific indications for this surgery. METHODS: A retrospective chart review was performed for 323 patients who underwent a reduction mammoplasty from August 2009 to July 2019 at Keck Hospital and LAC+USC Medical Center. Data regarding patient demographics, comorbidities, pre-operative breast characteristics, and post-operative complications were extracted. Student's t-test, Fisher's exact test, and logistic regression were performed in R. RESULTS: Of 323 patients, 15 received an FNG. Independent variables analyzed included: age, body mass index (BMI), obesity, smoking, diabetes, hypertension, surgical indication, sternal notch-to-nipple length, nipple-to-inframammary fold length, and weight of breast specimens removed. BMI, obesity, gigantomastia, and weight of specimen resected were significantly associated with use of the FNG (p < 0.001, p < 0.05, p < 0.0001, p < 0.0001, respectively). Regression analysis revealed that patients who had an average of more than 1500 g of tissue removed from each breast were 1.41 (95% CI: 1.17-1.71, p<0.001) times more likely to undergo an FNG procedure than those who had less than 1500 g of tissue removed. Demographic data and breast characteristics, such as notch-to-nipple length and nipple-to-inframammary fold length, were not significantly associated. CONCLUSION: Total weight of the breast specimens removed and BMI were significantly associated with the FNG technique. Removing more than 1500 g gof total breast tissue was also significantly correlated. These findings may guide surgeons during the decision-making process of when to use an FNG.

The Homelessness Crisis and Burn Injuries: A Cohort Study.

The United States is facing a growing homelessness crisis. We characterize the demographics and outcomes of homeless patients who sustain burn injury and compare them to a cohort of domiciled patients. A retrospective cohort study was performed at the Los Angeles County + University of Southern California Regional Burn Center for consecutive acute burn admissions in adults from June 1, 2015, to December 31, 2018. Patients were categorized as either domiciled or homeless at the time of their injury. Prevalence rates were estimated using data from the regional homeless count. From 881 admissions, 751 (85%) had stable housing and 130 (15%) were homeless. The rate of burn injury requiring hospitalization for homeless adults was estimated at 88 per 100,000 persons. Homeless patients had a significantly larger median burn size (7 vs 5%, P < .05) and a greater rate of flame burns (68 vs 42%, P < .001). For the homeless, rates of assault and self-inflicted injury were 4- (18 vs 4%, P < .001) and 2-fold higher (9 vs 4%, P < .001), respectively. Homeless patients had higher rates of mental illness (32 vs 12%, P < .001) and substance abuse (88 vs 22%, P < .001), and were less likely to follow-up as outpatients (54 vs 87%, P < .001). There was no difference in mortality. Homeless patients had a longer median length of stay (LOS; 11 vs 7 days, P < .001) without significant differences in LOS per percentage TBSA. Homeless individuals should be considered a high-risk population for burn injury. This distinction serves as a call to action for the development of burn prevention strategies.

Mesenchymal Stromal Cells Isolated from Irradiated Human Skin Have Diminished Capacity for Proliferation, Differentiation, Colony Formation, and Paracrine Stimulation.

Ionizing radiation, commonly used in the treatment of solid tumors, has unintended but deleterious effects on overlying skin and is associated with chronic nonhealing wounds. Skin-derived mesenchymal stromal cells (SMSCs) are a pluripotent population of cells that are critically involved in skin homeostasis and wound healing. The aim of this study was to isolate and functionally characterize SMSCs from human skin that was previously irradiated as part of neoadjuvant or adjuvant cancer therapy. To this end, SMSCs were isolated from paired irradiated and nonirradiated human skin samples. Irradiated SMSCs expressed characteristic SMSC markers at lower levels, had disorganized cytoskeletal structure, and had disordered morphology. Functionally, these cells had diminished proliferative capacity and substantial defects in colony-forming capacity and differentiation in vitro. These changes were associated with significant differential expression of genes known to be involved in skin physiology and wound healing. Conditioned media obtained from irradiated SMSCs affected fibroblast but not endothelial cell proliferation and migration. These results suggest that in situ damage to SMSCs during neoadjuvant or adjuvant radiation may play a critical role in the pathogenesis of slow or nonhealing radiation wounds. Stem Cells Translational Medicine 2019;8:925&934.

Human Acellular Dermis as Spacer for Small-Joint Arthroplasty: Analysis of Revascularization in a Rabbit Trapeziectomy Model.

BACKGROUND: Carpometacarpal joint osteoarthritis affects 8 to 12 percent of the general population. Surgical management provides symptomatic relief for 78 percent of patients who fail conservative therapy, but little consensus exists regarding which surgical procedure provides superior patient outcomes. Recent human trials substituted exogenous acellular dermal matrices in the bone space, but there are no quantitative histologic data on the outcome of acellular dermal matrices in this environment. The authors aimed to quantify the revascularization and recellularization of acellular dermal matrices in the joint space using a rabbit model. METHODS: Bilateral lunate carpal bones were surgically removed in New Zealand rabbits. Acellular dermal matrix and autologous tissue were implanted in place of the lunate of the right and left wrists, respectively. Acellular dermal matrix was also implanted subcutaneously as a nonjoint control. Histologic and immunofluorescence analysis was performed after collection at 0, 6, and 12 weeks. RESULTS: Quantitative analysis of anti-α-smooth muscle actin and CD31 immunofluorescence revealed a sequential and comparable increase of vascular lumens in joint space and subcutaneous acellular dermal matrices. In contrast, autologous tissue implanted in the joint space did not have a similar increase in α-smooth muscle actin-positive or CD31-positive lumens. Semiquantitative analysis revealed increased cellularity in both autologous and acellular dermal matrix wrist implants at each time point, whereas average cellularity of subcutaneous acellular dermal matrix peaked at 6 weeks and regressed by 12 weeks. Trichrome and Sirius red staining revealed abundant collagen at all time points. CONCLUSION: The trapeziectomy joint space supports both cellular and vascular ingrowth into human acellular dermal matrix.

Development and Characterization of A Novel Prox1-EGFP Lymphatic and Schlemm's Canal Reporter Rat.

The lymphatic system plays a key role in tissue fluid homeostasis, immune cell trafficking, and fat absorption. We previously reported a bacterial artificial chromosome (BAC)-based lymphatic reporter mouse, where EGFP is expressed under the regulation of the Prox1 promoter. This reporter line has been widely used to conveniently visualize lymphatic vessels and other Prox1-expressing tissues such as Schlemm's canal. However, mice have a number of experimental limitations due to small body size. By comparison, laboratory rats are larger in size and more closely model the metabolic, physiological, and surgical aspects of humans. Here, we report development of a novel lymphatic reporter rat using the mouse Prox1-EGFP BAC. Despite the species mismatch, the mouse Prox1-EGFP BAC enabled a reliable expression of EGFP in Prox1-expressing cells of the transgenic rats and allowed a convenient visualization of all lymphatic vessels, including those in the central nervous system, and Schlemm's canal. To demonstrate the utility of this new reporter rat, we studied the contractile properties and valvular functions of mesenteric lymphatics, developed a surgical model for vascularized lymph node transplantation, and confirmed Prox1 expression in venous valves. Together, Prox1-EGFP rat model will contribute to the advancement of lymphatic research as a valuable experimental resource.

Topical Fibronectin Improves Wound Healing of Irradiated Skin.

Wound healing is significantly delayed in irradiated skin. To better understand global changes in protein expression after radiation, we utilized a reverse phase protein array (RPPA) to identify significant changes in paired samples of normal and irradiated human skin. Of the 210 proteins studied, fibronectin was the most significantly and consistently downregulated in radiation-damaged skin. Using a murine model, we confirmed that radiation leads to decreased fibronectin expression in the skin as well as delayed wound healing. Topically applied fibronectin was found to significantly improve wound healing in irradiated skin and was associated with decreased inflammatory infiltrate and increased angiogenesis. Fibronectin treatment may be a useful adjunctive modality in the treatment of non-healing radiation wounds.

Integra-based Reconstruction of Large Scalp Wounds: A Case Report and Systematic Review of the Literature.

BACKGROUND: Large complex scalp wounds that have traditionally required free vascularized tissue transfer have been successfully reconstructed with skin substitutes such as Integra. Although there are multiple reports of Integra-based reconstructions of scalp wounds, there has not been a comprehensive assessment of this body of literature that critically examines this method. Our goal was to conduct a systematic review to determine the effectiveness of Integra-based reconstructions of scalp wounds, with emphasis on large defects. METHODS: A comprehensive systematic review was completed using key search terms, including Integra, dermal regeneration template, bovine collagen, skin substitute, forehead, and scalp. Selected articles reported characteristics of patients and their reconstructions. The primary outcome measures were wound complications and percent graft take. RESULTS: Thirty-four articles were included in this systematic review. Wound sizes ranged from 5.7 to 610 cm2, with 35.3% of articles reporting a mean defect size >100 cm2. Thirty-two articles reported mean percent take of skin graft ≥90%. Sixteen articles reported a minor complication. There were no major complications associated with the reconstructions. CONCLUSIONS: There is a substantial evidence base for the use of Integra to reconstruct scalp wounds. To date, the dermal regeneration template is generally reserved for salvage procedures or when the patient cannot tolerate free tissue transfer. Based on the findings of this systematic review and the authors' clinical experience, Integra can be used to achieve predictable results in large complex scalp defects.

Efficient Assessment of Developmental, Surgical and Pathological Lymphangiogenesis Using a Lymphatic Reporter Mouse and Its Embryonic Stem Cells.

Several lymphatic reporter mouse lines have recently been developed to significantly improve imaging of lymphatic vessels. Nonetheless, the usage of direct visualization of lymphatic vessels has not been fully explored and documented. Here, we characterized a new Prox1-tdTomato transgenic lymphatic reporter mouse line, and demonstrated how this animal tool enables the researchers to efficiently assess developmental, surgical and pathological lymphangiogenesis by direct visualization of lymphatic vessels. Moreover, we have derived embryonic stem cells from this reporter line, and successfully differentiated them into lymphatic vessels in vivo. In conclusion, these experimental tools and techniques will help advance lymphatic research.