Scientific Abstract Presentations: Abstract Topics Session 2 (Non-CME) Sunday, October 12 Sun, Oct 12 8:00-8:45 a.m. CDT

Purpose: Increasing rates of obesity in the US and incidence of breast cancer have resulted in growing demand for larger breast implant sizes for implant-based breast reconstruction(1). This study aims to evaluate whether the largest implant sizes (1340cc and 1445cc) from the Athena Clinical Trial (ClinicalTrials.gov NCT02724371) for breast reconstruction show clinically significant differences in outcomes compared to smaller sizes in the study and the benefit/risk ratio associated with these devices.

Methods: 3-year follow-up of 53 patients who received either 1340cc or 1445cc devices was conducted as part of a 10-year multicenter prospective investigational study evaluating safety and effectiveness of larger-volume implants in women undergoing post-mastectomy two-stage reconstruction. Safety (complications) and performance (satisfaction, including BREAST-Q) were analyzed using descriptive statistics.

Results: The largest implants in the Athena study were predominantly used in patients with BMI ≥35 (65.4% of those receiving 1340cc and 92.6% of those receiving 1440cc). Most patients, 42 (79.2%), with 1340cc or 1445cc devices retained their original implants at 3 years, while 11 (20.8%) required explantation. Ten of the 11 explanted patients were successfully reimplanted with another device from the study. In the revision reconstruction cohort, 90.9% of participants engaged in the study to increase their implant size due to the perception of insufficient volume in their reconstructed breasts. No significant differences were observed when comparing complication rates (including any reoperation, asymmetry, Baker Grade 3/4 capsular contracture, delayed wound healing, explantation, extrusion, malposition, infection) across device sizes using a univariate logistic regression model (Figure 1). Via BREAST-Q, patient-reported satisfaction levels showed similar high scores across lower (930-1240cc) and higher (1340-1445cc) sized devices in the study (Figure 2).

Conclusion: High BMI patients represent approximately half of the women currently presenting for breast reconstruction after mastectomy due to breast cancer(2). This highlights the need for larger breast implant sizes than 800cc for obese women, leading to the Athena Study of breast implants with volumes up to 1445cc. Although obese breast reconstruction patients have historically faced a higher risk of complications compared to their non-obese counterparts, data from this study revealed a favorable risk/benefit ratio for what are now the largest breast implants available on the US market. Implants larger than 1300cc required minimal revisions beyond size adjustments, with complication rates comparable to those of smaller devices. These high-volume implants demonstrated an acceptable explantation rate and high retention rates over three years. There was a strong association between the selection of these largest volume implants and women with a BMI ≥35, suggesting tailored utility for obese patients. Finally, patient and surgeon-reported outcome scores were high for these largest-volume implants, further justifying their use.

References: 1. Barone I, Giordano C, Bonofiglio D, Andò S, Catalano S. The weight of obesity in breast cancer progression and metastasis: Clinical and molecular perspectives. Semin Cancer Biol. 2020 Feb;60:274-284. 2. Srinivasa DR, Clemens MW, Qi J, Hamill JB, Kim HM, Pusic AL, Wilkins EG, Butler CE, Garvey PB. Obesity and Breast Reconstruction: Complications and Patient-Reported Outcomes in a Multicenter, Prospective Study. Plast Reconstr Surg. 2020 Mar;145(3):481e-490e.

Introduction/Purpose: Autologous tissue transfer with DIEP flap has revolutionized breast reconstruction. However, the donor site continues to be problematic with regard to postoperative abdominal laxity and risk of bulge. Extended intramuscular dissection or complex perforator course can create denervation of the rectus muscle, which places patients at higher risk of complications. Techniques to minimize the risk of bulge or abdominal wall weakness after DIEP flap breast reconstruction have been developed, including short fascial and pedicle lengths. The purpose of this study was to examine the feasibility of DIEP reconstruction with a short fascial incision to improve functional outcomes.

Methods:
189 DIEP flaps in 107 patients were performed between October 2021 and July 2024 by the senior author. All patients were included. Our control group included patients who underwent traditional DIEP flap harvest with fascial incision and pedicle length measuring between 12 to 15 centimeters (cm). We compared these to 25 patients with 48 DIEP flaps with a short fascial incision at or above the arcuate line between 7 and 12 cm, further categorized by ultra-short (<8 cm, n=14), short (8.1 to 10 cm, n=20), and moderate-short (10.1 to 12 cm, n=15) fascial lengths. Operative time, total morphine equivalents (ME) during post-operative stay, length of postoperative stay, and complication rates were analyzed.

Results: Ultra-short, short, and moderate-short fascial incisions had average pedicle lengths of 9.8cm, 11.1cm, and 11.9cm, respectively. We found a significant decrease in average total morphine equivalents (ME) required for postoperative pain control from 101.21 ME ± 168.48 (SD) for patients with traditional fascial incisions to 52.35 ME ± 55.35 for patients with short-fascial incisions (p = 0.02). Average length of stay decreased compared to the traditional fascial incision (1.86 days ± 0.86 vs. 2.67 days ± 1.94 p = 0.002). Operative time was shorter with 453 minutes ± 61.55 compared with 497 minutes ± 93.06 for traditional fascial incisions (p = 0.009). Flap failure rate was 1.07% and anastomotic revision rates were 0.53%. There were no flap failures in the short-fascial group. There was no significant difference in venous coupler size and major/minor complications between groups. Average follow up time was 10.1 months.

Conclusions: Short-fascial incision DIEP flap yields shorter operative time, nearly half the total morphine equivalents during postoperative stay, a shorter length of stay and faster recovery, without compromising flap viability. The short-fascial incision DIEP flap average pedicle length of 10.9 cm was adequate for comfortable microsurgery. All these advantages factor into using a short fascial incision in DIEP flap-based breast reconstruction

Background

The field of gender-affirming surgery is rapidly evolving, with plastic surgery units worldwide increasingly offering these services. Phalloplasty is a critical component of female-to-male (FTM) transition, providing significant psychological and functional benefits. However, there is no clear consensus on the optimal surgical technique for phalloplasty in this patient population. This systematic review examines the existing literature on the use of pedicle flaps and the free radial forearm flap in FTM gender-affirming surgery.

Methods

A systematic review was conducted following the PRISMA guidelines and was registered a priori (CRD42023479414) [1] . The search strategy adopted the Peer Review of Electronic Search Strategy (PRESS) guidance, searching PubMed/Medline, Scopus, Web of Science, ProQuest, and EBSCO for eligible studies [2]. Two independent reviewers screened and selected studies, resolving discrepancies by consensus. Flap survival and patient satisfaction were the primary outcome measures. Secondary outcomes included standing voiding ability, penetrative sexual function, number of operative stages, surgical duration, anesthetic techniques, and donor site morbidity or acceptance. Risk of bias was assessed using ROBINS-I, and evidence quality was evaluated using GRADE [3, 4].

Results

A total of 19 studies comprising 769 patients (614 radial forearm flaps, 155 pedicled anterolateral thigh flaps) were included. Both techniques demonstrated comparable outcomes, though the pedicled flap required significantly less operative time (290 vs. 516 minutes). Flap failure rates were low for both groups (1.9% radial forearm, 0.6% anterolateral thigh)(p = 0.348) and patient satisfaction was high (78% vs. 76.2%) (p = 1.0). Risk of bias assessment indicated serious selection bias due to the observational nature of studies. GRADE evaluation rated the evidence as low, reflecting the absence of randomized trials in this field.

Conclusion

The radial forearm flap remains the most reliable technique for phalloplasty, with the anterolateral thigh flap serving as a secondary option when the radial forearm flap is not feasible. However, the limited number of studies and the lack of standardized outcome reporting in gender-affirming surgery make it difficult to draw definitive conclusions or establish evidence-based recommendations. While both flap types are considered safe for female-to-male phalloplasty, the small patient cohorts and absence of randomized data contribute to the ongoing uncertainty in determining the optimal approach.

References 1. Page, M. J., McKenzie, J. E., Bossuyt, et. al. (2021). The PRISMA 2020 statement: An updated guideline for reporting systematic reviews. BMJ, 372, n71. https://doi.org/10.1136/bmj.n71

2. McGowan J, Sampson M, Salzwedel DM, Cogo E, Foerster V, Lefebvre C. PRESS peer review of electronic search strategies: 2015 guideline statement. J Clin Epidemiol. 2016;75:40-46. doi:10.1016/j.jclinepi.2016.01.021

3. Sterne J A, Hernán M A, Reeves B C, SavoviÄ J, Berkman N D, Viswanathan M et al. ROBINS-I: a tool for assessing risk of bias in non-randomised studies of interventions BMJ 2016; 355 :i4919 doi:10.1136/bmj.i4919

4. Brozek JL, Akl EA, Alonso-Coello P, et al. Grading quality of evidence and strength of recommendations in clinical practice guidelines. Part 1 of 3. An overview of the GRADE approach and grading quality of evidence about interventions. Allergy. 2009;64(5):669-677. doi:10.1111/j.1398-9995.2009.01973.x

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.

Introduction: Abdominoplasty is one of the most commonly performed plastic surgeries worldwide, with Brazil leading in procedure volume. Changes in eating behavior may occur before and after surgery, influencing weight gain. Weight fluctuations are linked to restrictive diets, emotional eating, and compensatory behaviors, contributing to metabolic and psychological disturbances (VITAGLIANO, 2023; ADAN, 2019). While studies show weight gain in women post-abdominoplasty (NAHAS et al., 2011), no research has examined the relationship between eating behavior and postoperative weight gain. Methods: This longitudinal clinical study included 51 women (25–50 years old) undergoing abdominoplasty at the Federal University of São Paulo (UNIFESP). Patients with chronic diseases, smoking habits, prior bariatric surgery, or additional aesthetic procedures were excluded. The Dutch Eating Behavior Questionnaire (DEBQ) and Binge Eating Scale (BES) assessed eating behaviors preoperatively and six months postoperatively (PO6). Nutritional status was evaluated through anthropometric measurements, including BMI adjustments for excess skin and fat removal. Results: The mean excess skin and fat mass (ESFM) removed was 832.90 ± 298.06 g, corresponding to 1.32 ± 0.48% of preoperative weight. Mean baseline weight (BW) was 62.6 ± 6 kg, increasing to 64.6 ± 6 kg at PO6, with a significant weight gain of 2.0 ± 2 kg (p < 0.05). BMI increased from 24.4 ± 1.7 kg/m² (POI) to 25.2 ± 2.1 kg/m² (PO6), with 56.9% of patients classified as pre-obese postoperatively. Significant increases in eating behavior scores were observed: • DEBQ total score: +4.5 ± 2.4 (p < 0.001) • Restrained eating: +0.8 ± 1.0 (p < 0.001) • Emotional eating: +2.2 ± 1.5 (p < 0.001) • External eating: +1.5 ± 1.0 (p < 0.001) The severity of binge eating (BES score) increased from 23.5 ± 7.0 (PRE) to 29.1 ± 3.0 (PO6) (p < 0.001). Women with severe BES scores preoperatively had higher BMI at both PRE and PO6, suggesting a link between binge eating and weight gain post-abdominoplasty. Discussion: Weight regain after body contouring procedures is consistent with findings from HENDERSON et al. (2023), who observed postoperative weight recovery in 11.81% of bariatric patients and 7.56% of non-bariatric patients. SAARINIEMI et al. (2014) reported improved body satisfaction and reduced eating disorder risk post-abdominoplasty, though additional studies were recommended. Psychological factors significantly influence weight outcomes. MCCOMB & MILLS (2021) found that exposure to idealized body images increased body dissatisfaction in perfectionist women, potentially leading to disordered eating. CARANO et al. (2012) emphasized that food intake is regulated by both hypothalamic and emotional mechanisms, with the lipostatic theory (KENNEDY, 1950) suggesting that rapid fat loss may trigger compensatory weight regain. ZIMMER et al. (2022) identified binge eating disorder (BED) in 10.8% of abdominoplasty patients, supporting the link between eating disorders and aesthetic surgery candidates. RAMOS et al. (2019) found 48% of rhinoplasty candidates had body dysmorphic disorder (BDD), emphasizing the need for preoperative psychological screening in plastic surgery patients. Post-bariatric patients undergoing body contouring surgery showed better long-term weight control (DE VRIES et al., 2020), yet nutritional and psychological challenges remain. HERMAN et al. (2015) and KOKOSIS & COON (2018) highlighted postoperative nutritional deficiencies, reinforcing the importance of dietary and behavioral management. Conclusion: Women undergoing abdominoplasty showed reduced control over binge eating and significant weight gain six months postoperatively. The findings highlight the need for nutritional and psychological support in abdominoplasty candidates to optimize postoperative weight maintenance and eating behavior.

Background: Microsurgery offers transformative reconstructive solutions for complex soft tissue defects in the breast, head and neck, and extremities, yet its intricate nature often results in prolonged operative times linked to complications such as flap failure, infections, and poor wound healing . (1) The independent effect of operative duration remains unclear due to limited, small-scale studies that treat it as a secondary variable, often yielding exaggerated and conflicting results. To date, no study has specifically evaluated the relationship between operative times and complications in microsurgery . (2) (3) (4) Given the associated morbidity, extended hospital stays, and higher costs, our study employs a novel multivariate meta-regression accounting for ischemia time, device use, and patient comorbidities to clarify this relationship and bridge the gap between theory and practice. We also explore strategies to reduce operative times, including the use of anastomotic coupling devices (ACDs) and co-surgeon utilization.

Methods: Pre-registered on PROSPERO (CRD42024544010) and following PRISMA guidelines, we systematically searched CENTRAL, Embase, Medline, and Web of Science from inception until June 2024, without restrictions. Two reviewers independently screened studies and extracted data, excluding low-quality studies per the Newcastle-Ottawa Scale. A random-effects multivariate meta-regression using REML assessed the association between operative time and complications, adjusting for moderators (e.g., ischemia time, age, obesity) while subsequent univariate analysis validated findings.

Results: Multivariate meta-regression on 34,790 patients revealed operation time (β=0.0338 , p<0.001) and ischemia time (β=0.2590 , p<0.001) as significant independent predictors of complication rates. Covariates such as age, hypertension, smoking, obesity, and diabetes were also significant. Univariate analyses demonstrated strong associations of ischemia time with reoperation (β=1.00 , p<0.0001) and infection (β=0.4242 , p<0.0001), while operation time was significantly associated with wound complications (β=0.015, 95% CI: 0.001–0.029, p=0.036) and medical complications (β=0.045 , p=0.003). ACD's reduced operative times (Δ=−47.17 minutes , p=0.0396) and co-surgeon's reduced complication rates (β^= - 5.6852 , p < 0.001). Heterogeneity remained high across all analyses (I^2 = 99.9%).

Conclusion: Our findings reveal that prolonged operative and ischemia times independently heighten complication risks in microsurgery, challenging the traditional 6-hour threshold . (4) By treating these factors as continuous variables, we demonstrate that even small increments in time can increase risk. We believe our study identified key methodological flaws in previous investigations, which may explain the conflicting "thresholds" reported in the literature.

1. Villavisanis DF, Zhang D, Shay PL, Taub PJ, Venkatramani H, Melamed E. Assisting in Microsurgery: Operative and Technical Considerations. J Hand Surg Glob Online. 2023;5(3):358-362. doi:10.1016/j.jhsg.2023.01.011

2. Haddock NT, Teotia SS. Efficient DIEP Flap: Bilateral Breast Reconstruction in Less Than Four Hours. Plastic and Reconstructive Surgery – Global Open. 2021;9(9):e3801. doi:10.1097/GOX.0000000000003801

3. Cheng H, Clymer JW, Po-Han Chen B, et al. Prolonged operative duration is associated with complications: a systematic review and meta-analysis. J Surg Res. 2018;229:134-144. doi:10.1016/j.jss.2018.03.022

4. Hardy KL, Davis KE, Constantine RS, et al. The impact of operative time on complications after plastic surgery: a multivariate regression analysis of 1753 cases. Aesthet Surg J. 2014;34(4):614-622. doi:10.1177/1090820X14528503

Background. Burn injuries are complex and challenging in both diagnosis and management. In the U.S., 1.25 million individuals need medical attention for burns annually, with 40,000 hospitalized. Early and accurate assessment of burn depth is crucial to determine the need for surgery but challenging. Visually assessing burn depth is complex, with experienced surgeons achieving only 50-75% diagnostic accuracy. Burn depth is considered a predictor of pathological scarring that occurs in 30%-91% of burn injuries. Objective and non-invasive approaches are needed. This study presents an Artificial Intelligence (AI) system leveraging large-scale pretraining for determining burn depth using both pre-clinical and human burn dataset including non-invasive Tissue Doppler Elastography Imaging (TDI), Harmonic B-mode ultrasound and digital wound photography.
Methods. Different burn degrees were induced on the back of twelve anesthetized Yorkshire pigs (70-80 lbs.) using a standardized electrically heated burn device per IACUC protocol. Burns were created with a 150°C block for 1,10, and 60 sec, resulting in six (2" x 2") wounds per pig, with two unburnt control sites. Human data (n=30) was collected from patients treated at American Burn Association (ABA)-verified burn center from May 2022 to May 2023 per IRP protocol. Eligible subjects had thermal burn injury within 72 hours after burn, without prior surgical debridement or intervention, male or female age 18-89 years old, and Total Body Surface Area (TBSA) involvement ≤ 75%. Chemical, electrical or radiation burns were not included. TDI to measure tissue stiffness, B-mode images, and digital photos were collected for 42 days. Biopsies were obtained from pigs and from the human subjects during debridement at OR. The AI model was trained on the pig data and validated with human data.
Results. Thirty patients were enrolled with one withdrawal. The age was 47.6± 17.6 years old, BMI= 28.8 ± 5.3 kg/m². Our model demonstrated high accuracy in detecting surgical cases and this was validated by histology. The model identified 100% of surgical cases (third-degree burns) for pig subjects. On human subjects, the model demonstrated high accuracy, it identified 7 out of 7 surgical cases (100%) and 15 out of 16 cases (94%) for non-surgical cases. The precision was 87%, sensitivity 100%, and an F1-score of 93%. The AUROC was 0.97, with a 95% Confidence Interval (CI) from 0.89 to 1.0. Critically, our system presented a clear and human-readable output to understand the surface of burn wounds, allowing a high degree of explainability often required to interpret AI-produced results. Conclusion. This work is the first to report a burn diagnostic system using non-invasive ultrasound TDI images and AI. Tissue stiffness measurements by TDI overcome the limitations of light-based technologies. Integrating AI to assist in TDI images interpretation results in a high degree of accuracy in predicting burn depth. Accurate early diagnosis of burn depth is expected to improve overall patient outcomes.