10:30 AM
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Impact of Topical Deferoxamine Used as a Radioprotective Agent on the Efficacy of Radiation Therapy in a Murine Model of Human Breast Cancer.
Purpose. This study investigates the impact of Deferoxamine Intradermal Delivery Patch (DIDP, Tautona-Group), applied topically as a skin radioprotectant, on the efficacy of radiation therapy. While the radioprotective properties of DIDP on the skin have been well-established in previous in vivo studies, its potential protective effects on cancer cells subjected to radiotherapy remain largely unexplored. Therefore, this research aims to elucidate whether the application of DIDP on the skin overlying tumor interferes with the induction of apoptosis in cancer cells following radiation therapy. Our research provides valuable insights into the interplay between DIDP as a radioprotective agent and the therapeutic effectiveness of radiation therapy in cancer treatment.
Methods. The study was performed on a murine model of human breast cancer developed by injecting 1x10^6 MCF7-Luc2 cancer cells (ATCC) into the mammary gland of 8-week-old female immunodeficient NSG mice. Once tumors reached an intensity of ~1x108 photons/s, mice were assigned to one of two cohorts: control and DFO-treated. DIDP were applied daily for 30 days until study endpoint. Radiation therapy (5 x 2 Gy dose daily; total 10 Gy) was administrated on the last 5 days of DIDP treatment using the RS-2000 irradiator (RadSource). The non-irradiated control mice were used to establish a baseline. Pre- and post-radiation in vivo tumor size was assessed using luciferin injection and LAGO bioluminescence imaging system. The day following radiation therapy, skin and tumor samples were preserved in 10% formalin and embedded in paraffin for downstream analyses. TUNEL staining (Abcam) and ImageJ software were utilized to detect and quantify the number of apoptotic cells. Statistical analysis was performed using ANOVA and GraphPad Prism software, with p < 0.05 considered significant.
Results. The quantitative analysis of TUNEL staining revealed a significant increase in the number of apoptotic cells in both the control group (FC=3.81, p<0.0001) and the DFO-treated group (FC=3.95, p<0.0001) following radiation therapy, indicating that irradiation was effective in both cohorts. Importantly, no significant differences were observed in the number of apoptotic cells when comparing irradiated control to irradiated DFO-treated mice (FC=0.8, p=0.131), suggesting that DIDP does not interfere with the efficacy of radiation therapy. Additionally, bioluminescence assays demonstrated no significant differences in tumor size after radiation therapy between the control and DFO-treated groups (FC=0.8, p=0.486). These findings further confirm that DIDP does not influence negatively the therapeutic effects of radiotherapy in breast cancer cells.
Conclusion. This study highlights the importance of evaluating the in vivo effects of radioprotective agents on cancer treatment outcomes to ensure their oncological safety. Specifically, we address the gap in understanding the interaction between DIDP and radiation therapy. The presented findings indicate that topical DFO treatment poses minimal risk of interfering with radiation therapy, as shown by no significant difference in tumor growth and tumor cell apoptosis following radiation therapy. DIDP does not compromise the efficacy of radiation therapy, most likely due to its inability to penetrate deeper tissues. In conclusion, our study suggests that DIDP may be safely used as a radioprotective treatment in oncological settings.
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10:35 AM
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Evidence-Based Perioperative Incisional Care in Plastic Surgery: A Narrative Review
Introduction
Perioperative incisional care is essential in plastic surgery for minimizing complications and optimizing outcomes, yet conflicting guidelines from major health organizations, such as the World Health Organization (WHO) [1], the Centers for Disease Control and Prevention (CDC) [2], and the Society for Healthcare Epidemiology of America (SHEA) [3], create variability in clinical practice. A survey of American Society of Plastic Surgeons (ASPS) members highlights this variability, revealing a lack of consensus on best practices incisional care techniques [4]. Further complicating surgical protocols, the FDA's removal of bacitracin in 2020 due to nephrotoxicity concerns has altered the use of triple antibiotic solution, leading to a shift toward alternative irrigation strategies [5]. Given these ongoing changes and practice inconsistencies, an evidence-based approach to perioperative incisional care in plastic surgery is critical for improving patient safety and surgical outcomes.
Methods
A comprehensive literature search of PubMed, MEDLINE, and Embase (2000–2025) was performed using defined terms ("clean surgical wounds," "plastic surgery," "incisional care"). Randomized controlled trials, systematic reviews, and meta-analyses focusing on six key areas-antiseptic preparation, wound irrigation, suture materials, wound closure devices, dressings, and topical agents-were prioritized. Studies pertaining to non-English publications, contaminated wounds, chronic wounds, and animal models were excluded. References were further compared with guidelines from health organizations, including the NIH, WHO, CDC, and ASPS. A narrative review was chosen over a systematic or scoping review to provide a structured synthesis of diverse evidence, integrating various study designs, expert consensus, and clinical guidelines to better inform clinical decision-making in plastic surgery.
Results
Six evidence-based recommendations emerged. First, 4–5% alcohol-based CHG is preferred for preoperative antisepsis. Second, antiseptic solutions (e.g., CHG or PVP-I) are recommended for irrigation over normal saline, and routine antibiotic irrigation is discouraged to mitigate antimicrobial resistance. Third, standard sutures are generally favored over barbed or antimicrobial-coated sutures. Fourth, 2-octyl-cyanoacrylate adhesives pose a high risk of hypersensitivity reactions, while silk fibroin strips offer improved biocompatibility and paper tapes remain useful for low-tension incisions. Fifth, traditional dressings remain adequate for most clean wounds, while closed-incision negative pressure wound therapy (ciNPWT) and silver dressings may benefit chronic wounds. Sixth, plain petrolatum is a safe topical agent, as antibiotic ointments confer no additional benefit and increase antibiotic resistance risks.
Conclusion
This narrative review synthesizes current evidence to offer six actionable, perioperative recommendations tailored to Class 1 clean incisions in plastic surgery. By synthesizing current evidence, this review serves as a comprehensive resource to guide clinical decision-making and optimize surgical outcomes for plastic surgeons.
References
[1] WHO. Global Guidelines for the Prevention of Surgical Site Infection. 2018. NCBI.
[2] Berríos-Torres SI, et al. CDC Guideline for SSI Prevention. JAMA Surg. 2017;152(8):784. doi:10.1001/jamasurg.2017.0904.
[3] Anderson DJ, et al. SSI Prevention in Acute Care: 2014 Update. Infect Control Hosp Epidemiol. 2014;35(6):605-627. doi:10.1086/676022.
[4] Epps MT, et al. Pocket Irrigation in Reconstructive Surgery: ASPS Survey. Ann Plast Surg. 2019;82(6S):S427-S432. doi:10.1097/SAP.0000000000001790.
[5] Oleru OO, et al. Bacitracin Ban & Infection Rates in Breast Reconstruction. Clin Breast Cancer. 2023;23(3):e103-e108. doi:10.1016/j.clbc.2022.12.019.
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10:40 AM
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Inguinal Lymph Nodes Flap Transfer Promotes Lymphatic Channel Formation in the Rat Sciatic Nerve
Introduction: The potential role of the lymphatic system in peripheral nerve regeneration is explained by its ability to prevent edema, thereby reducing the risk of intraneural compartment syndrome and subsequent demyelination. Additionally, its anti-inflammatory properties and contribution to neovascularization help create a supportive environment for nerve regeneration. However, the presence and functional significance of the lymphatic system in peripheral nerves remain poorly understood.
Objectives: Our primary objective is to investigate the presence and characteristics of the lymphatic structures within the normal rat sciatic nerve. The secondary objective is to develop a lymphatic tissue transfer model and evaluate its ability to promote lymphatic channel formation within the nerve.
Methods: Immunofluorescence (IF) staining was performed on Wister Lewis rat sciatic nerve using podoplanin (PDPN), a specific marker for lymphatic endothelium, along with CD31, an endothelial marker for blood vessels that is also expressed in lymphatic vessels [1]. For lymphatic tissue transfer, rat inguinal lymph nodes (LN) were harvested with adipose tissues as a pedicled SIEA flap [2] and positioned around the transected and repaired sciatic nerve, ensuring close proximity of the LN to the neural repair site. Eight weeks post-surgery, IF staining was performed on the nerve covered by the inguinal LN flap. The number of PDPN- and/or CD31-positive areas within a 500 um square region was counted by five independent volunteers who were not associated with this project. The averages were then compared among three groups: normal nerve (control), transected and repaired nerve (neurorrhaphy only), and transected and repaired nerve covered by the inguinal LN flap (LN flap coverage).
Results: IF staining of the normal rat sciatic nerve revealed that PDPN/CD31 double-positive areas adjacent to CD31 single-positive areas on the outer side of the nerve fibers, specifically within the fibrofatty tissue surrounding the epineurium. Counting by five independent volunteers demonstrated that the average number of PDPN/CD31 double-positive areas was significantly higher in the LN flap coverage group than in the control (45.6 vs. 2.6, p = 0.0002) and the neurorrhaphy-only groups (45.6 vs. 2.0, p = 0.0002).
Discussion: Our results confirm the presence of lymphatic vessels adjacent to blood vessels in the fibrofatty tissue of the normal rat sciatic nerve. Considering that lymphatic channels were nearly absent within the nerve fibers in the control and neurorrhaphy-only groups, the significant increase observed in the LN flap coverage group suggests that the transferred inguinal LN facilitated lymphatic channel formation, potentially supporting nerve regeneration.
Conclusion: The inguinal LN flap transfer significantly promotes lymphatic channel formation within sciatic nerve fibers. This suggests that the transferred LN contributes to lymphatic channel induction, potentially enhancing nerve regeneration and tissue repair following peripheral nerve injury.
References
[1] Breiteneder-Geleff S, et al. Angiosarcomas express mixed endothelial phenotypes of blood and lymphatic capillaries: podoplanin as a specific marker for lymphatic endothelium. Am J Pathol. 1999 Feb;154(2):385-94.
[2] Saffari TM, et al. The Superficial Inferior Epigastric Artery Fascia Flap in Rats. J Reconstr Microsurg Open 2020; 05(01): e7-e14.
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10:45 AM
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Shaping the Future of Plastic Surgery: Training and Career Paths of Residency Program Directors
Introduction
Diverse residency cohorts are essential to alleviating health disparities and improving patient outcomes. Residency program directors (PD) play a critical role in selecting and mentoring the next generation of plastic surgeons, influencing the academic, clinical, and demographic landscape of the field. Understanding the training background, fellowship pathways, and geographic distribution of current plastic surgery PDs can help guide future workforce development. The goal of this study is to analyze the educational and professional trajectories of plastic surgery PDs across accredited integrated plastic surgery residency programs in the United States.
Methods
PD demographic and training information was extracted from 89 accredited integrated plastic surgery residency programs identified through the American Society of Plastic Surgeons (ASPS) website. Medical school, residency program, and fellowship program data were collected through publicly available sources, including institutional faculty pages and LinkedIn.
Results
Among the 89 PDs analyzed, 77% were male and 22% were female. Regarding fellowship training, 24% did not pursue a fellowship beyond plastic surgery residency. Among those who completed fellowships, 24% specialized in hand surgery, 22% in craniofacial surgery, 12% in reconstructive/microsurgery, and 6% in breast/aesthetic surgery. Fellowships in burn, pediatric, critical care, cosmetic surgery, or microvascular surgery were pursued by 2% or fewer PDs. Additionally, 26% of PDs hold advanced degrees, with MBAs (30%) and PhDs (17%) being the most common. 19.1% of PDs completed training before 1990, 32.6% in the 2000s, 42.7% in the 2010s, and 1.1% in the 2020s. 4.5% of PD training years were not publicly available. Geographically, 21% of PDs remained in the state where they completed their plastic surgery residencies. 4.5% of PDs are directors of their medical school alma mater. 15.7% of program directors completed a general surgery residency where they serve as PDs and 22.5% of PDs completed their plastic surgery residency where they serve as PDs.
Conclusions
A majority of PDs are fellowship-trained, with the most common specializations being hand and craniofacial surgery. Female PDs remain underrepresented in program leadership. There is a prevalence of advanced degrees, particularly MBAs and PhDs, among PDs. Additionally, most PDs completed their training after 2000. These findings may inform future efforts to diversify leadership, optimize training pathways, and enhance the residency training experience.
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10:50 AM
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Assessment of Patient Handouts on Burns created by Burn Surgeons compared to ChatGPT-4o
Background: Educating patients may be difficult for physicians in plastic surgery due to limited time. Large language models (LLMs), such as ChatGPT, have illustrated promising results in patient education across various specialties. The present study's aim was to investigate the reliability and accuracy of ChatGPT-generated patient handouts regarding burns and compare these results to a published handout.
Methods: We asked ChatGPT-4o to generate and regenerate patient handouts for seven topics regarding burns: Burn injuries, burn surgery, skin care, nutrition, exercise, daily activities, and coping with your burns. These 14 handouts, along with a patient handout with similar topics published by Hamilton Health Sciences, were assessed. A panel of seven individuals involved in burn care, including 1 occupation therapist, 1 physiotherapist, 1 social worker, 3 board-certified burn surgeons, and 1 senior plastic surgery resident, assessed the handouts. The Quality of Generated Language Outputs for Patients (QGLOP) scale was used to assess handouts based on accuracy/comprehensiveness, bias, currency, and tone, where each domain was scored out of 4 for a total of 16. The Simple Measure of Gobbledygook (SMOG) score was calculated to assess handout readability. The threshold for statistical significance was set at p<0.05.
Results: The mean (SD) QGLOP scores for the ChatGPT-4o generated handouts and the published handout did not significantly differ (11.19 (2.12) vs. 11.03 (2.35); p=0.522). The mean (SD) QGLOP scores between ChatGPT-4o and the published handout were not significantly different for accuracy (2.79 (0.61) vs. 2.69 (0.71); p=0.646), bias (2.79 (0.61) vs. 2.83 (0.61); p=0.582), currency (2.76 (0.70) vs. 2.72 (0.66); p=0.575), or tone (2.85 (0.62) vs. 2.78 (0.76); p=0.379). ChatGPT-4o had lower scores on the topic of skin care (9.80 (1.44) vs. 11.20 (1.64); p=0.046), but higher scores on coping with burns (12.10 (3.11) vs. 11.00 (2.35); p=0.046). The two groups did not significantly differ for any other topic. The SMOG score for all ChatGPT-4o and published handouts were 11.23 and 9.82, respectively.
Conclusions: In this study, we found that ChatGPT was capable of producing patient education handouts on burns with scores comparable to those of a patient handout published by a burn unit, suggesting that plastic surgeons would have a similar level of satisfaction for both groups. The SMOG score of ChatGPT-generated handouts were higher than the published handout, suggesting that both groups require at least a high school level of education to comprehend the text, but the LLM may pose greater challenges for patients with lower levels of education. Our results replicate studies in ophthalmology. (1) Further studies are needed to investigate patient perspectives on handouts generated by LLMs, explore whether LLMs confer a productivity benefit when writing handouts for physicians in plastic surgery, and determine the most ethical and least harmful approach to utilizing LLMs effectively in medicine.
References:
1. Tao BK, Handzic A, Hua NJ, Vosoughi AR, Margolin EA, Micieli JA. Utility of ChatGPT for Automated Creation of Patient Education Handouts: An Application in Neuro-Ophthalmology. J Neuroophthalmol. 2024;44(1):119-124. doi:10.1097/WNO.0000000000002074
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10:55 AM
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Collagen is a Promising Substrate for Engineering Clinically Relevant Vascularized Tissue Flaps Using “Reset” Vascular Endothelial Cells
Background: Autologous tissue transfer is commonly used by reconstructive surgeons for defect restoration. However, a common complication of this is skin necrosis due to insufficient re-vascularization and perfusion. Engineering vascularized tissue flaps might limit these complications by promoting revascularization and perfusion while sparing donor sites. Past research in our lab has shown that reset vascular endothelial cells (R-VECs) (human umbilical vein endothelial cells transduced to express ETV2, an embryonic transcription factor that regulates early angiogenesis and is normally not expressed after 20 weeks in gestation) can self-assemble into microvascular networks in microfluidic chip systems using 3 mg/mL collagen as a biocompatible extracellular matrix. This study aims to demonstrate that R-VECs can form microvascular networks in collagen extracellular matrices of various concentrations in both microfluidic systems and a 3 cm2 collagen "flap" stimulated by shear stress.
Methods: For the microfluidic system, 300,000 R-VECs were suspended in 30 μl of extracellular matrix composed of 3 mg/ml, 4 mg/ml, 5 mg/ml, or 6 mg/ml collagen isolated from rat tail tendons. Suspensions were plated in a microfluidic chip via an inlet well, which flowed across a channel to an outlet well. The chips were incubated until the matrix polymerized and 1 cc cylinders were attached to each well and filled with media at the inlet side. The microfluidic chip systems were incubated at an angle to encourage gravitational media flow to exert shear stress on the R-VECs. For human-scale flaps, 10 million R-VECs were suspended in 2 mL of 8 mg/ml collagen (same cell to collagen proportions as the microfluidic system) and poured into a mold creating 2 empty channels representing an artery and vein within the flap. The construct is allowed to polymerize to a solid and then perfused anterograde through the artery channel and retrograde through the vein channel with media at 1 dyne using a peristaltic pump to apply shear stress. All constructs were imaged using light or fluorescent microscopy after 24 hours for the microfluidic system and 4 days for the "flap" to assess microvascular network formation.
Results: Microvascular networks formed after 24 hours in 3, 4, and 5 mg/mL groups, suggesting that R-VECs suspending in collagen up to 5 mg/ml are capable of forming microvascular networks in a microfluidic system. These networks appeared to have similar morphology between groups. 6 mg/ml collagen-R-VEC suspension would not flow through the microfluidic system due to high viscosity. After 4 days of perfusion, the R-VECs within the 8 mg/ml collagen "flap" showed morphologic and behavioral changes characteristic of early microvascular network formation but required more time for the network to reach maturity.
Conclusions: This study demonstrates the formation of microvascular structures by RVECs within extracellular matrices of increasing collagen concentrations up to 5 mg/ml in a microfluidic system and early microvascular network formation in 8 mg/ml collagen in a 3 cm2 "flap". Further optimization of this technology holds promise for developing scalable and hierarchical vascular networks for engineering human scale tissue flaps for surgical anastomosis.
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11:00 AM
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Predicting Breast Cancer-Related Lymphedema (BCRL) following Axillary Lymph Node Dissection (ALND): A Systematic Review of Current Prediction Models
Background:
Breast cancer-related lymphedema (BCRL) is a debilitating complication affecting one-third of patients undergoing axillary lymph node dissection (ALND). Since BCRL is incurable, early risk identification is essential for prevention. Prediction models have been developed to assess BCRL risk based on demographic, oncologic, and treatment-related factors. However, variability in study populations and model performance has led to inconsistent findings, limiting clinical applicability. This systematic review critically evaluates existing prediction models for BCRL, identifies key risk factors, and synthesizes current evidence to enhance risk stratification.
Methods:
A systematic review was conducted on PubMed, Embase, and Web of Science to identify studies reporting prediction models for BCRL in patients undergoing ALND in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines . Outcome data included the cumulative incidence of lymphedema, time from ALND to BCRL diagnosis, model performance (Area Under the Curve), predicted risk factors, odds ratio (OR), and hazard ratio (HR). Studies that include patients who have not had ALND, less than 12 months of follow-up (mean or median), lymphedema before ALND, or lacking incidence of BCRL were excluded. Only statistical models with more than two clinical risk factors were included.
Results:
Of 1,827 screened articles, 38 met the inclusion criteria. Overall, 21,466 patients with a mean follow-up time of 50.8 months were included. 27.5% of patients developed BCRL on average 16.9 months following ALND. The predictors most commonly associated with BCRL were BMI (19 models), radiation (18 models), chemotherapy (17 models), number of axillary lymph nodes removed (11 models), age (7 models), surgical complications (7 models), level III ALND (5 models), race (3 models), and number of positive lymph nodes (3 models).
Higher BMI was significantly associated with an increased risk of BCRL, with BMI >30 showing ORs ranging from 2.36 to 5.27 (p<0.05). Non-white race was linked to a higher BCRL risk (OR 2.34–4.54, p<0.05). Radiation therapy (OR 1.93–15.34, HR 1.38–4.90; p<0.05) and chemotherapy (OR 1.39–5.30, HR 1.45–4.14, p<0.05) significantly increased the risk. The extent of ALND was a key predictor, with the removal of more than 10 nodes associated with ORs of 1.71–2.57 (p<0.05), while the removal of more than 20 nodes had an OR of 5.65 (p<0.05). Level III dissection also elevated risk (OR 2.02–7.89, HR 2.39; p<0.05). Surgical complications within 30 days, including seroma and infections, were significantly associated with BCRL development (OR 1.46–5.27, p<0.05).
Conclusion:
This systematic review is the most comprehensive study that synthesizes existing prediction models for BCRL to date. Patients with higher BMI, racial minorities, and those who receive radiation, chemotherapy, or require more extensive ALNDs are more likely to develop BCRL following surgery. Despite variations in predictive models, these risk factors were consistently identified. However, differences in model validation highlight the need for a standardized, clinically applicable prediction tool to guide prevention strategies.
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11:05 AM
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Size Matters: The Impact of Lipoaspirate Processing Technique on Adipocyte Cell Size in Autologous Fat Grafting
Purpose: Autologous fat grafting (AFG) is a minimally invasive procedure in which a patient's own adipose tissue is transferred to a targeted area for volume retention. While commonly used in breast reconstruction, there is significant variation in fat graft volume retention. Our previous study demonstrated differences in volume retention based on lipoaspirate processing techniques, with standard decantation resulting in worse volume retention compared to active wash and filtration (AWF) or low-pressure (LP) decantation. However, specific factors affecting volume retention remain unclear, with adipocyte cell diameter being a potential influence, as smaller cells may be less prone to shearing. This study aims to evaluate adipocyte cell size in AFG using these three techniques.
Methods: A prospective, blinded, randomized clinical trial was conducted at our institution from March 2021 to July 2023 (ClinicalTrials.gov identifier: NCT04891510). Patients were randomized to receive either standard decantation, AWF, or LP decantation. Approximately 10 cc of lipoaspirate was collected, fixed overnight in 10% formalin, dehydrated with 70% ethanol, and embedded in paraffin. Hematoxylin and eosin (H&E) slides were sectioned for microscopy, and cell diameter was measured using Zeiss software by two independent investigators. ANOVA was used to compare adipocyte diameter between groups, and linear regression assessed the correlation between adipocyte size and volume retention.
Results: Forty-four patients were enrolled in the trial: 17 (38.6%) patients received standard decantation, 16 (36.4%) received AWF, and 11 (25.0%) received LP decantation. Groups did not differ significantly in age or body mass index (p > 0.05). There was no significant difference in average cell size across standard decantation, AWF, and LP decantation (88.1 microns vs. 90.1 microns vs. 90.1 microns; p > 0.05). However, the distribution of cell sizes varied by technique. The AWF method resulted in a skew toward smaller cell sizes, while both standard and LP decantation techniques exhibited a normal distribution around the mean. Simple linear regression analysis revealed no significant correlation between adipocyte size and volume retention.
Conclusions: Our findings suggest that larger adipocyte cells may be filtered out with the AWF technique, indicating that lipoaspirate processing techniques may be used to select for different adipocyte cell sizes. Although our data did not show a correlation between adipocyte size and volume retention, further research is needed to explore the relationship between the adipocyte microenvironment and fat graft retention.
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11:10 AM
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AAV Gene Therapy for Digit Regeneration Informed by Spatial Transcriptomics
Introduction: Limb loss presents a significant clinical challenge that stands to benefit from fields such as gene therapy. Mouse digit tip (MDT) regeneration serves as a mammalian model of complex tissue regeneration that can provide insight into strategies for enhancing tissue repair and bone lengthening after limb amputation. However, little is known about optimal gene therapy methods for manipulating this process. This study employed spatial transcriptomics to identify gene promoters active in key anatomic regions of the regenerating MDT. Subsequently, promoter sequence fragments were tested in adeno-associated viral vector (AAV) assays for their ability to enhance bone regeneration by driving overexpression of a potent osteogenic effector gene (BMP2).
Methods: Hindpaw digits of 8-week-old BALB/cJ mice were amputated at the level of the middle (P2) or distal (P3) phalanx. Fourteen days post-amputation (dpa), samples were processed through the STOmics Stereo-seq platform to delineate gene expression in anatomic sub-regions of the regenerating digit. Proximal promoter fragments (2 kb) were cloned from the Krt16, Postn, or Col1A2 genes and placed upstream of the BMP2-3xFLAG coding sequence, followed by plasmid synthesis and packaging into AAV8 vectors. AAV8 CMV:GFP vectors were used as controls. At 10 dpa, vectors were systemically delivered by retro-orbital injection. At 14 dpa, digits were harvested for histological analysis or Stereo-seq. P3- and P2- amputated digits were collected at 21 dpa and 28 dpa timepoints, respectively, for micro-CT analysis. Scans were reconstructed and scaled in ImageJ. Whole and segmental measurements of length, thickness, and volume were obtained for regenerating bone, then normalized by comparison with corresponding original amputated digit tips.
Results: Stereo-seq analysis revealed a rich architecture of genetically distinct regions of the digit. Differential gene expression in keratinocyte populations allowed for segregation of epidermal cells into computationally defined clusters, localized to the regeneration epidermis (RE). Osteogenic genes, such as Ibsp, Sparc, Spp1, Postn, Bglap, and Alpl, were induced in both P3 and P2 amputations compared to uninjured P3 digits. Spatially localized GFP expression in areas of the MDT suggested successful transduction of injected AAV constructs, whereas anti-FLAG immunofluorescence revealed promoter-specific patterning of viral construct expression. Mice injected with AAV8 POSTN:BMP2-3xFLAG demonstrated increased P3 regenerated volume when normalized and compared to the GFP control mice (mean 550% ± 250% vs 190% ± 60%, p=0.0085), and increased P2 regenerated volume relative to GFP control mice (mean 180% ± 86% vs 98% ± 47%, p=0.0159). AAV8 KRT16:BMP2-3xFLAG showed increased thickness (mean 72% ± 10% vs 49% ± 3.7%, p=0.0086) and volume (190% ± 81% vs 98% ± 47%, p=0.0467) in P2 regenerated digits. Trabecular structural properties appeared similar between mice injected with AAV8 COL1a2:BMP2-3xFLAG and those injected with control virus.
Conclusion: This study presents a novel methodology for identifying AAV control sequences in the MDT and suggests that bony digit regeneration can be enhanced by spatially directed overexpression of BMP2. Ongoing work seeks to probe cell type-specific dynamics and associated signaling pathways modulated by these vectors. This work may lead to new approaches for treating complications of limb loss through AAV gene therapy.
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11:15 AM
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Advancing Competency Based Training in Plastic Surgery: Developing Entrustable Professional Activities
Introduction: In 2023, the American Board of Surgery introduced Entrustable Professional Activities (EPAs) as a framework to assess general surgery residents' competence, advancing the shift toward standardized competency-based education (CBE) (1). EPAs define discrete units of professional practice (tasks) that trainees can be entrusted to perform independently once they demonstrate sufficient competence. However, the broad clinical scope of plastic and reconstructive surgery (PRS) presents unique challenges in defining a comprehensive EPA framework. To address this gap, this study aims to develop and validate PRS-specific EPAs, creating a competency-based framework tailored to PRS residency training.
Methods: A modified multi-stage methodology, based on Dr. ten Cate's established approach to EPA development (2,3), was employed. A 12-member task force from the American Council of Educators in Plastic Surgery (ACEPS) was convened and received structured guidance from Dr. ten Cate. The task force followed a structured timeline that included literature review and educational videos, expert consultation, and consensus-driven prioritization of PRS-specific EPAs.
Results: Using the Nominal Group Technique (NGT) (4), the ACEPS Task Force systematically identified and prioritized PRS-specific EPAs. An initial long list of EPAs was generated, followed by iterative refinement through anonymous voting, merging, and categorization. Some EPAs were designated as sub-EPAs within broader core EPAs, while others were reclassified as skills, knowledge, and attitudes (KSA) necessary for entrustment rather than standalone EPAs.
A preliminary list of 17 core PRS EPAs has been developed, encompassing key domains such as oncological breast reconstruction, craniofacial trauma surgery, acute and traumatic hand, and aesthetic surgery of the face. For each core EPA, detailed activity descriptions including focus, and the scope of practice are currently being refined by the ACEPS Task Force.
Conclusion: The next phase of development will involve a modified Delphi consensus process consisting of two rounds of review by ACEPS members to refine and validate the EPAs. Additionally, entrustment level descriptions will be mapped to ACGME competencies and milestones.
This study represents a critical step in defining competency-based training in PRS. By employing a systematic approach, we have developed a preliminary EPA framework that reflects the complexity of PRS practice. Further efforts will focus on piloting these EPAs in a multicenter study, with the goal of establishing a validated competency-based training model for plastic surgery residency programs.
ACEPS Task Force
Chair: Esther Kim
EPA Expert Consultant: Olle ten Cate
Members: Keith Brandt, Kim Bjorklund, Amanda Gosman, Scott Lifchez, Vu Nguyen, Peter Taub, Don Mackay, Aaron Mason, Mike Neumeister, David Tang, David Ross
References:
- American Board of Surgery. (2024, December 20). Entrustable Professional Activities (EPAs) | ABS. https://www.absurgery.org/get-certified/epas/
- ten Cate, O., Nel, D., Hennus, M.P., Peters, S.., Romao G.S.- For which entrustable professional activities must medical students be prepared if unsupervised patient care without further training is an expectation? An international Global South study: BMJ Global Health 2024;9:e016090.
- Ten Cate, O., & Taylor, D. R. (2020). The recommended description of an entrustable professional activity: AMEE Guide No. 140. Medical Teacher, 43(10), 1106–1114. https://doi.org/10.1080/0142159X.2020.1838465
- Lee SH, ten Cate O, Gottlieb M, Horsley T, Shea B, Fournier K, Tran C, Chan T, Wood TJ, Humphrey-Murto S. The use of virtual nominal groups in research: an extended scoping review PLoS One 2024;19(6): e0302437.
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11:20 AM
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Scientific Abstract Presentations: Research & Technology Session 3 - Discussion 1
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11:30 AM
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Enhancing Wound Healing in Plastic Surgery: Promoting Angiogenesis via Gene Upregulation Using Titanium Dioxide Nanoparticles
PURPOSE: Titanium dioxide nanoparticles (TiO₂ NPs) are highly regarded for their biocompatibility, antimicrobial effects, and light-scattering properties, making them promising candidates for various biomedical applications, particularly in regenerative medicine and wound repair. Previous studies indicate that TiO₂ NPs can enhance the activity of human umbilical vein endothelial cells (HUVECs) by upregulating adhesion molecules and inflammatory markers, suggesting a potential role in stimulating angiogenesis, a crucial process in effective wound healing [1]. This study aims to examine the effects of TiO₂ NPs on angiogenesis in HUVECs, focusing on their role in vascular network formation and gene regulation. To achieve this, we utilized:
• Flow cytometry and cell sorting
• Time-lapse fluorescence imaging (EVOS microscopy) to track real-time vascular development,
• Network analysis (Celleste Image Analysis software) for quantifying angiogenic branching,
• Scanning electron microscopy (SEM) for structural characterization, and
• Reverse Transcription Polymerase Chain Reaction (RT-PCR)
METHODS: HUVECs were cultured with or without 0.1 mg/mL and 0.2 mg/mL Rutile TiO₂ nanoparticles for 24 hours to assess their impact on angiogenesis. Following treatment, cells were plated on 10 mg/mL Matrigel, and capillary formation was monitored every 20 minutes for 24 hours using EVOS fluorescence microscopy with a CO₂ on-stage incubator. Images from triplicate cultures were analyzed using Celleste Image Analysis software to quantify vascular network formation. Mechanical stress exerted by HUVEC networks on the substrate was evaluated using the Digital Image Speckle Correlation (DISC) method. To assess angiogenesis-related gene expression, RT-PCR was performed on TiO₂ NP-treated HUVECs at two time points: Day 0 (immediately after 24-hour exposure) and Day 1 (following an additional 24-hour incubation post-washing with PBS to remove excess NPs). Additionally, fluorescence-activated cell sorting (FACS) was used to determine TiO₂ NP uptake in HUVECs treated with 0.1 mg/mL TiO₂ NPs.
RESULTS: HUVECs treated with TiO₂ nanoparticles exhibited more stable and extensive vascular networks, characterized by an increased number of branches, tubes, and nodes compared to the control group. Mechanical stress analysis indicated that TiO₂-treated cells applied less force on the substrate while forming these networks. SEM imaging confirmed the integration of TiO₂ nanoparticles within cellular structures, particularly within nodes and splines, while TEM analysis revealed that the nanoparticles were predominantly localized within vacuoles adjacent to mitochondria. Gene expression analysis via RT-PCR demonstrated a significant upregulation of VEGFR2 and HGF in HUVECs treated with 0.1 mg/mL TiO₂ over consecutive days. However, VEGF expression showed a delayed response, becoming upregulated only on the second day. These findings indicate that TiO₂ nanoparticles may indirectly enhance VEGF expression by first stimulating the production of other growth factors.
CONCLUSIONS: This study demonstrates that TiO₂ nanoparticles enhance angiogenesis in HUVECs, suggesting potential applications in wound healing. Further research is ongoing to uncover the underlying mechanisms and confirm TiO₂'s therapeutic potential in regenerative medicine.
REFERENCES:
1. Montiel-Dávalos, A., Ventura-Gallegos, J. L., Alfaro-Moreno, E., Soria-Castro, E., García-Latorre, E., Cabañas-Moreno, J. G., del Pilar Ramos-Godinez, M., & López-Marure, R. (2012). TiO2 nanoparticles induce dysfunction and activation of human endothelial cells. Chemical research in toxicology, 25(4), 920–930.
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11:35 AM
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Transforming Powder Dressing for Lower Extremity Wounds in Patients with Diabetes: A Multinational Case Series
Purpose: Lower extremity wounds, particularly diabetic foot ulcers (DFUs), present a significant challenge due to impaired healing, high infection rates, and the risk of amputation. Advanced wound care strategies are needed to address the multifactorial nature of these wounds, particularly in resource-limited settings. Transforming Powder Dressing (TPD) offers a novel approach by creating a moisture-retentive, semi-occlusive environment that enhances granulation tissue formation, reduces exudation, and prolongs dressing intervals. This multinational case series evaluates the real-world efficacy of TPD in managing diabetic lower extremity wounds across diverse healthcare settings.
Methods: A retrospective, multicenter case series was conducted across four regions (Egypt, India, Palestinian Territories, and UAE) with seventeen patients between 2019 and 2020. DFU's classified as Wagner Grade 2 or 3 were included. TPD was applied to the wound bed and covered with a secondary dressing, with dressing changes performed every 5–7 days. Outcomes assessed included time to complete epithelialization, dressing change frequency, pain reduction, and complications. Statistical analyses compared healing times across wound classifications.
Results: The mean age of the cohort was 57.6 years (range: 37–68), with 76.5% (n=13) male patients. The majority of wounds (88.2%, n=15) were located on the feet, with 76.5% (n=13) classified as Wagner Grade 3. Mean wound duration before TPD application was 9.4 months (range: 1 week–18 years). The average time to full wound closure was 46 days (range: 19–116 days). Wagner Grade 2 ulcers healed faster (mean: 37 days) than Grade 3 ulcers (mean: 48 days). Dressing change intervals averaged 7 days, significantly reducing dressing frequency compared to standard wound care. Pain reduction was reported after the first application in most cases, and no cases required amputation during the study period. Complications were minimal, with only one case of minor blistering that resolved without intervention.
Conclusions: Transforming Powder Dressing (TPD) demonstrated significant promise as an advanced wound care modality for lower extremity wounds, offering faster healing times, reduced dressing changes, and improved patient comfort. Its ability to manage Wagner Grade 3 ulcers highlights its potential in treating complex wounds, particularly in diabetic populations. The findings suggest that TPD could provide a cost-effective alternative to standard dressings while minimizing complications. Further prospective, controlled studies are warranted to validate these results and assess the long-term impact of TPD in wound care protocols.
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11:40 AM
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Impact of Muscle Fiber Composition on RPNI Performance in a Rodent Model
Introduction: Amputation can significantly decrease quality of life, highlighting the need for functional and intuitive neuroprosthetics (1). While there have been major improvements in the engineering front in developing advanced neuroprosthetics, lack of a biologic interface has limited their application. Regenerative Peripheral Nerve Interface (RPNI) has demonstrated the ability to amplify small efferent action potentials from peripheral nerves, allowing for direct recording from reinnervated muscles in the form of electromyography (EMG) signals for neuroprosthetic control (2). RPNIs are created by securing a transected nerve into a denervated muscle graft, allowing reinnervation of the muscle graft (3). Currently, muscle graft selection is based on the availability of donor muscle regardless of its fiber type composition. To date, no studies have looked into the effect of muscle fiber type composition on the amplitude of muscle signals generated by RPNI constructs. This study aims to investigate how muscle grafts composed of different fiber types impact compound muscle action potentials (CMAPs) elicited from RPNIs in a rodent model.
Methods: Nine 6-weeks old male Fischer rats were assigned to 3 different groups based on the muscle graft used to create the RPNI construct: soleus (composed of 80% type I fibers), peroneus longus (PL) (composed of 42% type IIx fibers), and extensor digitorum longus (EDL) (composed of 64% type IIb fibers). Muscles were harvested from the ipsilateral side of each rat, and common peroneal (CP) nerve was isolated, transected, and secured into the center of the muscle graft. In total, 18 RPNIs were created bilaterally, with six RPNIs per group. After a maturation period of 3 months, the constructs were isolated, CMAP measurements were recorded, and RPNIs were harvested for histological analysis.
Results: Preliminary results showed excellent revascularization in all groups, as evidenced by adequate turgor. Muscle contractions were observed in all constructs, indicating functional reinnervation. Varying degrees of muscle graft atrophy were noted: soleus at 28%, PL at 22%, and EDL at 12%. Post-maturation construct weights were: soleus 79 mg, PL 85 mg, and EDL 83 mg. Soleus, PL, and EDL produced a maximum CMAP amplitude of 6.5 mV, 7.1 mV, and 9.9 mV, with a signal-to-noise ratio of 32.2 dB, 30.6 dB, and 38.3 dB, respectively. Histological analysis revealed normal muscle fiber morphology across all groups.
Conclusion: We demonstrated that RPNIs are able to generate reliable and significant muscle signals in a rodent model in situ with high signal-to-noise ratio regardless of the initial muscle fiber type composition.
References:
1. Yamamoto M, Chung KC, Sterbenz J, et al. Cross-sectional international multicenter study on quality of life and reasons for abandonment of upper limb prostheses. Plastic and Reconstructive Surgery - Global Open. 2019;7(5). doi:10.1097/gox.0000000000002205
2. Vu PP, Irwin ZT, Bullard AJ, et al. Closed-loop continuous hand control via chronic recording of regenerative peripheral nerve interfaces. IEEE Transactions on Neural Systems and Rehabilitation Engineering. 2018;26(2):515-526. doi:10.1109/tnsre.2017.2772961
3. Vu PP, Vaskov AK, Irwin ZT, et al. A regenerative peripheral nerve interface allows real-time control of an artificial hand in upper limb amputees. Science Translational Medicine. 2020;12(533). doi:10.1126/scitranslmed.aay2857
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11:45 AM
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Developing an Innovative Scalpel that Provides Improved Surgical Views and Reduced Beveling
Background: The surgical scalpel has been used for thousands of years in one form or another. In the late 1800s, Schott patented the idea of attaching a disposable blade to the scalpel, allowing for sharp blades to be used in sterile fields (1). Since this time, little innovation has occurred in the field of scalpels. The current scalpel is linear, unable to show a view of what is being cut. This can cause inexperienced surgeons to tilt their blades-also known as beveling-to gain a view of what is being cut. This causes inaccurate and beveled incisions which can lead to poor incision healing and patient dissatisfaction. In this project, we sought to improve these current flaws with a new scalpel design.
Methods: To improve the scalpel, we began to think about ways to create a scalpel that allowed improved visualization while creating a surgical incision. The major goal was to allow a view of the upcoming line where we would be cutting. We began by sketching out various designs to find what would allow visualization. We proceeded to model the designs using 3D modeling software. We continued by 3D printed our designs and receiving feedback on each iteration. The goal from each iteration was the improve the field of view of the scalpel and the comfort of the scalpel.
Results: We had a total of 12 different designs that we considered in this process. Our final design (figure 1) includes a tail that splits apart into two handles, connected by a bridge style finger grip, before joining into the tip where the blade attaches. This design allows for full visualization of the upcoming cut and allows the surgeon to easily follow the pre-drawn incision line. This design also reduces beveling because there is no longer a need to tilt the scalpel to see the line. We also were able to add grips to the scalpel on the sides and top to improve comfort and ease of use.
Conclusions: Through this project, we have created a new scalpel which we believe may allow surgeons to create more accurate incisions, cut at a consistent depth, reduce beveling, increase efficiency, and improve comfort. We have begun comparing the new scalpel to current scalpels with agar gels that mimic human skin. We are comparing cuts made on the agar gel using ultrasound and optical coherence tomography to allow us to see if there is a benefit to our new scalpel and in which use cases it would function best.
- Elson NC, Yoder LM, Dick KD, Meister KM, Wexelman BA. Mathilde Schott, A Woman's Influence in the Revolution of the Scalpel in the 1890s. Am Surg. 2023 Nov;89(11):5044-5046. doi: 10.1177/00031348221142574. Epub 2022 Nov 25. PMID: 36426756.
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11:50 AM
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PPAR-γ modulates aging associated mitophagy dysfunctions in dermal adipose tissue
Background: In various skin diseases, adipocyte progenitor cells within the dermis and dermal fat layer are disrupted by upstream signaling interference, resulting in impaired adipogenesis. This dysfunction in dermal adipose tissue(dWAT) leads to compromised anti-infective and metabolic regulatory capabilities. DWAT dysfunction has been observed in the aging skin microenvironment. However, whether the loss of dWAT directly contributes to the deterioration of the dermal microenvironment remains unclear. The objective of this study was to investigate the mechanistic role of PPAR-γ loss in dermal adipose dysfunction and its impact on skin aging and fibrosis.
Methods: In this study, we established a murine model of dermal adipose dysfunction using the PPAR-γ inhibitor GW9662 and analyzed the dermal microenvironment to determine the regulatory role of dermal adipose tissue. In vitro, we induced cellular senescence in the murine preadipocyte cell line 3T3-L1 using hydrogen peroxide (H₂O₂) and assessed adipogenic capacity and extracellular matrix (ECM) remodeling. Furthermore, we co-cultured 3T3-L1 cells with murine fibroblasts to evaluate the paracrine effects of adipocytes on fibroblast proliferation, migration, and collagen synthesis. To determine whether PPAR-γ is a key regulator of mitochondrial quality control in adipocytes, we monitored mitochondrial damage, autophagy, and mitophagy in 3T3 cells with PPAR-γ overexpression (OE) and knockdown (KD).
Results: Mice with dermal adipose dysfunction exhibited exacerbated dermal fibrosis and aging-related changes. Senescent 3T3 cells demonstrated impaired adipogenesis and reduced paracrine effects on fibroblasts. PPAR-γ downregulation was accompanied by increased TGF-β1 expression, enhanced fibrosis, and upregulated α-SMA, a marker of myofibroblast differentiation, indicating adipocyte-to-myofibroblast transition (AMT) in dermal adipose tissue. Proteomic analysis of dermal adipose tissue identified an enrichment of mitochondrial-associated proteins. Senescent 3T3 cells also exhibited mitochondrial damage and disrupted mitophagy. In PPAR-γ KD 3T3 cells, mitochondrial swelling, fragmentation, impaired mitochondrial respiration, and decreased PINK1-PARKIN-mediated mitophagy were observed.
Conclusion: Our study demonstrates that dermal adipose dysfunction is present in the aging skin microenvironment and serves as a pathogenic factor contributing to skin aging and fibrosis. PPAR-γ regulates adipocyte function through mitophagy modulation, thereby influencing the dermal microenvironment.
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11:55 AM
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Trends and Gender Differences in Publications by Matched Plastic Surgery Applicants from 2019 to 2024
Background: Publications are a key element of a successful plastic surgery residency
application. Trends in the number of publications across years and the subspecialties
within plastic surgery that successful applicants publish in is not well studied.
Methods: A list of all integrated plastic surgery programs was obtained from the
American Society of Plastic Surgery website and current residents were identified using corresponding residency program webpages. Manuscripts published prior to residency were queried using PubMed and ResearchGate and filtered into the following categories: craniofacial, aesthetic, breast, gender affirming, microsurgery, hand, basic science, non-plastic surgery, and nonsurgical. The number of first author publications was noted.
Results: A total of 914 residents from 87 programs were included. From 2019 to 2024, the overall number of publications (12.4 vs. 7.00), first author papers (3.80 vs 1.89), and percentage of open access publications (16.1% vs. 28.9%) significantly increased (p<0.05). Male applicants had more total publications (11.9 vs 8.51) and first author publications (3.79 vs 2.66) than female applicants (p<0.05). Applicants from "Ivy League" medical schools also had significantly more total publications than their counterparts (18.0 vs 9.31, p<0.05). On average, applicants had the most non-plastic surgery (2.30), nonsurgical (1.73), and craniofacial (1.49) papers published and had the least microsurgery (0.509), hand (0.324), and gender affirming (0.348) papers. From 2019 to 2024, the number of aesthetic (1.16 vs 0.272), breast (1.42 vs. 0.628), hand (0.824 vs. 0.193), microsurgery (0.824 vs 0.235), gender affirming (0.503 vs 0.125), and non-plastic surgery (2.77 vs. 1.22) papers significantly increased (p<0.05) (Figure 2).
Conclusion: The number of total and first author publications from successful plastic
surgery applicants have significantly increased over the past six years, with applicants
increasingly publishing aesthetic, breast, hand, microsurgery, gender affirming, and
non-plastic surgery publications. Male applicants overall publish more than female applicants, and applicants from Ivy League medical schools publish more than their counterparts. The number of open access publications has also significantly increased.
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12:00 PM
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Cutting Through the Clot: Rethinking Venous Thromboembolism Prophylaxis in Plastic Surgery with Aspirin, Direct Oral Anticoagulants, and Low Molecular Weight Heparin
Background
Venous thromboembolism (VTE) remains a critical concern in plastic and reconstructive surgery due to factors such as prolonged operative duration, perioperative immobility, and procedure-specific risks (1). To mitigate this, prophylactic anticoagulation, traditionally with low-molecular-weight heparin (LMWH), has been widely adopted. However, following trends in other specialties, the use of direct oral anticoagulants (DOACs) and aspirin (ASA) is gaining traction as viable alternatives (2,3). This scoping review aims to summarize current practices surrounding the use of these medications in VTE prophylaxis for plastic surgery patients. There is limited consensus among plastic surgeons regarding standardized VTE prophylaxis protocols, which is why this scoping review specifically examines various approaches to thromboprophylaxis across various plastic surgery procedures.
Methods
A systematic search of Embase, PubMed, and the Cochrane register of clinical trials was conducted following PRISMA guidelines. Studies focusing on prophylaxis in plastic surgery were included, specifically those evaluating VTE rates, complications, or clinical outcomes with ASA, DOACs, or LMWH. Non-plastic surgery specialties or studies combining multiple anticoagulants without separate analysis were excluded. Data extraction included drug dosage and duration, follow-up, VTE rates, bleeding or hematoma, reoperation, and other complications. Descriptive statistics and qualitative analysis were performed.
Results
Of 884 studies screened, 241 full texts were analyzed, and 7 met inclusion criteria. In total, 3,475 patients were included (35% male, 65% female). Among the included studies, two examined the use of ASA (n=402), four focused on DOACs (n=2056), and four evaluated LMWH (n=802). While interventions varied, the most common regimens were ASA 325mg for 5 days postoperatively and DOAC 10mg for 10 days, while LMWH doses varied widely. VTE rate was similar across ASA (0.7%), DOAC (0.2%), LMWH (0.6%). The incidence of hematoma was lowest in the DOAC group (0.8%) when compared to ASA (4%), and LMWH (2%). Reoperation within 30 days was highest in the ASA group (6%), while both DOAC (1%) and LMWH (1%) had the lowest rates. Other complications (e.g. infection, seroma) were lowest in the DOAC group (5%) when compared to ASA (34%), and LMWH (13%).
Conclusion
This review underscores the existing evidence on VTE prophylaxis in plastic surgery, highlighting differences in efficacy and safety among ASA, DOACs, and LMWH. While VTE rates were comparable across all groups, the ASA group exhibited the highest risk of hematoma and reoperation. These findings emphasize the need to balance thromboprophylaxis efficacy with bleeding risk, particularly in high-risk surgical populations. The absence of standardized guidelines underscores the need for large-scale, procedure-specific randomized controlled trials to optimize prophylaxis strategies, minimize variability in care, and reduce complications associated with VTE management.
References
1. Gould, M. K., Garcia, D. A., Wren, S. M., Karanicolas, P. J., Arcelus, J. I., Heit, J. A., & Samama, C. M. (2012). Prevention of VTE in nonorthopedic surgical patients: antithrombotic therapy and prevention of thrombosis: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines. Chest, 141(2), e227S-e277S.
2. Morales Jr, R., Ruff, E., Patronella, C., Mentz III, H., Newall, G., Hustak, K. L., ... & Bush, A. (2016). Safety and efficacy of novel oral anticoagulants vs low molecular weight heparin for thromboprophylaxis in large-volume liposuction and body contouring procedures. Aesthetic Surgery Journal, 36(4), 440-449.
3. Fan, K. L., Black, C. K., Abbate, O., Lu, K., Camden, R. C., & Evans, K. K. (2019). Venous thromboembolism in plastic surgery: the current state of evidence in risk assessment and chemoprophylactic options. Journal of Plastic Surgery and Hand Surgery, 53(6), 370-380.
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12:05 PM
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Modulation of Digit Regeneration by Gene Therapy based on Conserved Epidermal Factors
The loss of limbs presents a significant challenge in clinical practice. Gene therapy offers promising approaches for regenerative treatments, yet established methods for precise control of molecular signaling pathways and the development of suitable vectors are still lacking (1). The mouse fingertip regeneration model is widely recognized for studying regeneration following amputation injuries in mammals, as adult mice can successfully restore the distal phalanx after transverse amputations involving the nail matrix (2). In all species capable of appendage regeneration, the initial formation of a specialized regeneration epidermis (RE) over the amputation site is essential for restoring lost structures (3). The RE functions as a key signaling unit that directs blastema formation and subsequent appendage regrowth (4). However, the mammalian RE remains relatively unexplored, particularly in comparison to highly regenerative species.
To promote tissue regeneration after limb loss, we gained insights from organisms with a high endogenous capacity for tissue regrowth. First, we analyzed the regeneration epidermis (RE) of the zebrafish caudal fin using single-cell RNA sequencing, identifying the Sp family as key epidermal transcription factors, acting upstream of Fgf8 signaling. Subsequently, we observed a significant impairment in bony fingertip regeneration in mice with a basal epidermis-specific knockout of Sp6 and Sp8, as confirmed by computed tomography (CT) scans at 28 days post-amputation (dpa), compared to wild-type mice, as shown in Image 1.
Further, we utilized spatial transcriptomics (BGI StereoSeq) to investigate the spatial organization of the mammalian RE. Mapping distinct zones within the mouse digit RE enables the identification of targeted gene therapy interventions. By using adeno-associated viral (AAV) vectors with fluorescent reporters, we screened multiple serotypes and enhancers for efficient and localized transduction of the mouse digit tip. Our experiments demonstrated restricted viral gene expression to the amputated digit and liver, which persisted over an approximate 10-day period.
To enhance mammalian digit regeneration, we engineered AAV constructs to overexpress Fgf8 in the mouse digit RE. This AAV-based gene therapy successfully improved fingertip regeneration in Sp-knockout mice and accelerated fingertip regeneration in wild-type mice. Further research is ongoing to elucidate transcriptional changes associated with Sp family knockout and to assess the potential of AAV-based therapies in rescuing digit regeneration phenotypes.
Our findings indicate that key components of the RE are conserved across evolutionarily divergent species and that the Sp-Fgf pathway is a fundamental modulator of appendage regeneration. This research deepens our understanding of regenerative mechanisms and introduces a gene therapy-based strategy for enhancing mammalian digit regeneration. By applying these insights, we can advance translational applications in innovative therapeutic strategies for limb loss and tissue reconstruction.
References:
1. Kohn DB, Chen YY, Spencer MJ. Successes and challenges in clinical gene therapy. Gene Therapy. 2023/11/01 2023;30(10):738-746. doi:10.1038/s41434-023-00390-5
2. Goldman JA, Poss KD. Gene regulatory programmes of tissue regeneration. Nat Rev Genet. Sep 2020;21(9):511-525. doi:10.1038/s41576-020-0239-7
3. Aztekin C. Tissues and Cell Types of Appendage Regeneration: A Detailed Look at the Wound Epidermis and Its Specialized Forms. Front Physiol. 2021;12:771040. doi:10.3389/fphys.2021.771040
4. Tassava RA, Loyd RM. Injury requirement for initiation of regeneration of newt limbs which have whole skin grafts. Nature. Jul 7 1977;268(5615):49-50. doi:10.1038/268049a0
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12:10 PM
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Clinical Documentation Quality in PRS: A Comparative Analysis of Medical Student Notes and LLM-Generated Documentation
Purpose:
Medical documentation is particularly important in plastic and reconstructive surgery (PRS), where detailed operative planning, complex wound assessments, and precise anatomical descriptions directly impact patient outcomes. Despite its importance, documentation remains challenging for trainees. As artificial intelligence tools such as large language models (LLMs) emerge, their potential application in plastic surgery warrants exploration. We evaluated the role of ChatGPT in improving patient summaries and mitigating medical student knowledge gaps through a quantitative evaluation of documentation quality in common PRS clinical scenarios.
Methods:
A prospective, blinded assessment of clinical documentation was conducted across three authorship modalities: medical student-generated summaries, AI-generated summaries prompted by medical student notes, and AI summaries transcribed from the same clinical encounters. Standardized patients were assigned three common plastic surgery presentations: burn management, flexor tendon repair, and zygomatic arch fracture. Documentation quality was evaluated using the validated Physician Documentation Quality Instrument (PDQI-9) by two evaluators blinded to note authorship. ChatGPT o3-mini was used for all AI assessments. Summary statistics were generated, and continuous variables were analyzed using t-tests. Significance was set at p<0.05.
Results:
Ten medical students who had already completed a PRS third-year rotation and planned to apply to PRS residency programs, participated in all three patient encounters. While all documentation methods produced clinically acceptable notes, medical student documentation (n=30) demonstrated significantly lower overall quality scores (40.9±2.4) compared to AI-prompted notes (43.0±1.6) and AI-transcribed notes (44.6±0.8; p<0.001). The most substantial disparities were observed in thoroughness (medical students: 3.9±0.7 vs. AI-transcription: 4.9±0.2, p<0.001), organization (4.1±0.6 vs. 5.0±0.1, p<0.001), and usefulness (4.3±0.6 vs. 4.9±0.2, p<0.001). Medical students demonstrated relative strengths in being succinct (4.8±0.4) and internally consistent (4.9±0.3). Diagnostic accuracy was significantly higher in AI-generated documentation (97%) compared to medical student notes (83%, p<0.001). Student notes were consistently shorter (137±46 words) than AI-prompted (186±27 words) and AI-transcribed (179±25 words) documentation (p<0.001). After completing the encounter, 5 students (50%) believed that ChatGPT better summarized the encounter, and only 2 students (20%) thought that they had created a better summary statement.
Conclusions:
AI has significant potential as a complementary tool in PRS documentation, particularly when paired with strong history-taking skills. The findings that ChatGPT was found to be superior to medical students in organization, thoroughness, usefulness, and comprehensibility validate previous studies that show ChatGPT's ability to summarize medical histories based on transcriptions. Concurrently, concise documentation is important in this surgical field, and AI tends to dilute clinical information with excessive words. Medical education should, therefore, focus on teaching students to work effectively with these tools and consider using ChatGPT as a comparison group to assess longitudinal medical student improvement.
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12:15 PM
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The Future of Healthcare: Leveraging Machine Learning to Establish a Point-of-Care Tool
Introduction: Objective assessment tools are essential for accurate diagnosis, proper management, research collaboration, and patient education. Many medical conditions lack such objectivity, resulting in opinion-based care and inconsistent management. This study describes how we developed a point-of-care (POC) tool using machine learning to objectively quantify craniosynostosis severity for clinical use.
Methods: Our POC tool development involved two components: (1) a machine learning processing pipeline and (2) an accessible web platform. The pipeline (Figure 1) began with an internet-based survey administered to expert craniofacial providers who evaluated the severity of metopic and sagittal craniosynostosis cases alongside normal controls. These ratings validated a principal-component-analysis ML model that generates metopic severity scores (MSS) and sagittal severity scores (SSS). We also developed an unsupervised machine learning model that produces cranial morphology deviation (CMD) scores to quantify skull variation from normal parameters. The web platform was developed using frontend and backend frameworks to ensure accessibility for clinicians. The system was programmed to process Digital Imaging and Communications in Medicine (DICOM) files, the most common format for computed tomography scans. When providers upload a patient's CT image, without including any protected health information, they receive a quantitative severity score in less than 1 hour.
Results: Since its clinical deployment in 2020, our diagnostic platform has facilitated the analysis of over 440 patient radiological examinations. The system has contributed to 150+ research presentations and generated more than 10 peer-reviewed publications. Currently, the platform maintains an active user base of 189 healthcare professionals and clinical researchers.
Conclusions: Our utilization metrics demonstrate substantial adoption and integration into existing clinical workflows, suggesting the potential for broader implementation. Clinicians can now leverage machine learning to objectively assess craniosynostosis severity at the point of care through our tool. This has significantly advanced craniosynostosis research, fostered global collaborations, and most importantly helped to inform enhance health literacy and guide patient care. We believe this methodology can be widely applied to other medical conditions that currently lack objective assessment tools.
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12:20 PM
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Scientific Abstract Presentations: Research & Technology Session 3 - Discussion 2
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