Scientific Abstract Presentations: Abstract Topics Session 3 - Non CME Saturday, October 17 Sat, Oct 17 5:00-6:00 p.m. CDT

BACKGROUND Implant-based reconstruction remains the most common approach to post-mastectomy breast reconstruction. Advances in surgical technique have shifted reconstructive practice from the submuscular to the prepectoral plane; however, limited data exist regarding how implant characteristics have evolved during this transition. The purpose of this study was to assess temporal trends in implant volume and projection in the context of this paradigm shift. We hypothesized that the transition from submuscular to prepectoral implant placement would be associated with the use of smaller-volume, less-projected implants, based on the premise that the pectoralis muscle may partially obscure full device projection. METHODS A single institution retrospective review was performed of patients who underwent unilateral immediate two-stage implant-based reconstruction from January 2012 to December 2024. Trends in implant volume and projection, body mass index (BMI), as well as plane of implant placement, were analyzed across the study period. Multivariable analysis was used to assess the association of patient demographic, oncologic, and surgical characteristics, including plane of implant placement, on implant volume and projection over time. RESULTS Overall, 2,032 patients were included; 403 underwent prepectoral reconstruction, and 1,629 underwent submuscular reconstruction. The median age was 52 years, 44% of patients underwent neoadjuvant chemotherapy, and 24% underwent postoperative radiation. Between 2012 and 2018, submuscular implant placement was the predominant technique at the study institution. Prepectoral implant placement gained traction in 2018, and the number of cases with this technique continued to increase as the number of submuscular cases decreased. In mid to late 2021, prepectoral plane placement became the predominant technique. The average implant volume and projection were highest in 2016 (515 cc and 5.23 cm, respectively) and lowest in 2024 (424 cc and 4.74 cm, respectively). There was no concurrent trend in BMI observed during these years. Prepectoral implant placement was associated with smaller implant volume (Beta= -20, 95% CI: -38 to -3.1, p=0.021) and lower projection (Beta= -0.17, 95% CI: -.30 to -0.05, p=0.005) compared with submuscular placement. CONCLUSION Over a 12-year period, implant selection in breast reconstruction has trended toward smaller volumes and lower projections. Although these changes may reflect evolving aesthetic preferences, our analysis suggests that the plane of implant placement may also be an important explanatory factor. This study offers contemporary insight into reconstructive practice patterns and helps inform modern implant selection strategies.

Introduction: Auricular framework carving remains one of the most technically demanding steps in microtia reconstruction and continues to rely on antiquated two-dimensional (2D) methods, including tracing the contralateral ear onto transparent projection film. While commonly used, these 2D templates fail to capture the three-dimensional (3D) relationships between auricular subunits and their relative planes, often resulting in poor anatomic fidelity and suboptimal framework geometry. Even with accurate 2D tracings, the lack of depth, subunit contour, and inter-subunit spatial relationships contributes to inconsistent outcomes. We present the development of a 3D, auricular subunit–specific, interlocking template system designed to address these limitations and improve reproducibility of framework construction.

Methods: Three-dimensional auricular framework templates were designed using computer-aided design (CAD) software and fabricated in autoclavable resin using a Stratasys J55 Prime PolyJet 3D printer (patent pending). Individual subunit templates incorporated a tongue-in-groove interlocking mechanism to facilitate assembly and provide inherent structural stability. Two antihelical templates with open and closed crural configurations were created to accommodate variability in available costal cartilage surface area. Perforations within each template permitted placement of 25-gauge needles for temporary fixation to the cartilage block during template tracing.

Results: A complete 3D template set was generated, consisting of four base components, two antihelical variants, a tragal unit, and a helical unit. Three base components interlocked to form the foundation, while a fourth served as a platform for the tragus and helical root. The tragal and antihelical components interlocked and overlaid the base framework, whereas the helical template overlaid the base independently. This modular system preserved three-dimensional subunit relationships during framework design, enabling early visualization of cartilage allocation and subunit spacing prior to carving. The dual antihelical variants allowed preselection of crural configuration based on available cartilage.

Conclusion: By replacing antiquated 2D projection-based tracing methods with a modular 3D interlocking template system, this approach directly addresses a key technical limitation in auricular framework carving: the inability to reliably reproduce anatomic subunit relationships and spatial planes. These templates may improve geometric accuracy, structural stability, and reproducibility of auricular frameworks, particularly for trainees or surgeons early in their learning curve, and they warrant further evaluation in operative and simulation-based settings.

Background Acellular dermal matrix (ADM) is commonly used to provide anterior implant support in implant-based breast reconstruction (IBBR). While prior studies have reported broadly comparable clinical outcomes with ADM, less is known about its impact on operative course and institutional financial performance beyond direct costs. This study evaluated perioperative, clinical, and financial outcomes associated with anterior ADM support using a propensity score-matched design that controlled for operative, oncologic, and patient-level confounders.

Methods A retrospective review of 569 implant-based breast reconstructions performed from 2017 to 2023 was conducted. Patients were grouped by use of anterior ADM support versus no ADM. Propensity score matching was performed 1:1 using nearest-neighbor matching without replacement, controlling for age, body mass index, timing of reconstruction, laterality, plane of implant placement, mastectomy type, axillary dissection, regional blocks, smoking status, comorbidities (coronary artery disease, chronic obstructive pulmonary disease, chronic kidney disease, congestive heart failure, hypertension, diabetes mellitus), and oncologic treatment (radiation, chemotherapy), yielding 55 matched pairs. Paired t-tests and McNemar testing were used for continuous and binary outcomes, respectively.

Results ADM use was associated with longer operative duration (264.0 vs 222.0 minutes; p=0.021), while length of stay did not differ significantly (0.93 vs 0.71 days; p=0.11). Total morphine milligram equivalents (59.7 vs 46.4; p=0.17) and average daily morphine milligram equivalents (51.0 vs 41.1; p=0.18) were similar between groups. Thirty-day postoperative phone or portal encounters (1.45 vs 2.05; p=0.18) and number of breast revisions (1.20 vs 1.27; p=0.70) did not differ. Seroma occurred more frequently with ADM (36.4% vs 18.2%; p=0.018), whereas infection rates were similar between groups (11.1% vs 11.1%; p=1.00). Other complications, implant loss, and 30-day readmissions were not significantly different. Financially, ADM cases incurred higher total charges ($83,042 vs $53,154; p<0.001) and higher total costs ($26,818 vs $14,303; p<0.001), including higher direct costs ($18,064 vs $9,047; p<0.001) and indirect costs ($8,754 vs $5,256; p<0.001). Estimated reimbursement trended higher with ADM ($22,383 vs $16,942; p=0.062), but overall margin was significantly lower (−$4,435 vs $2,640; p=0.0048). Margin calculated on direct costs alone remained positive and did not differ significantly ($4,319 vs $7,896; p=0.16). At final follow-up, most patients underwent definitive implant-based reconstruction (76.4% vs 78.2%), while autologous reconstruction occurred in 7.3% and 12.7% of patients, respectively.

Conclusion In a propensity-matched cohort, anterior ADM support was associated with longer operative times, higher seroma rates, and substantially higher direct and indirect costs. Although reimbursement trended higher, overall margin was lower with ADM use, while margins based on direct costs remained comparable, suggesting that differences were driven primarily by longer operative time and hospital resource demands rather than material costs alone.

Introduction: Medical adhesive-related skin reactions remain an underrecognized complication of surgical wound closure, with reported rates ranging from 3% to 60%. Silk fibroin, a protein from Bombyx mori, has emerged as an alternative dressing material with favorable immunologic properties. We systematically reviewed the clinical evidence for silk fibroin dressings in postoperative wound closure. Methods: Following PRISMA guidelines, we searched PubMed, Embase, Scopus, and Web of Science for human clinical studies evaluating silk fibroin as a topical dressing or closure device on surgical wounds. Animal-only, in vitro, suture-only, and non-surgical wound studies were excluded. Reviewers independently screened 1,665 records. Google Trends data were analyzed to assess temporal search interest. Data were analyzed with Python (v3.12.3). Results: Four studies met inclusion criteria from 93 full-text reviews. Four studies with extractable data (2 RCTs, 2 retrospective cohorts; N = 591) were analyzed (Table 1). Across all studies, allergic contact dermatitis was 0% with silk fibroin versus 6.4-52% with synthetic controls (all P < .05) (Table 2, Figure 2). Silk dressings were associated with reduced pharmaceutical intervention, faster application, and cost savings up to $466 per case (Figure 3). Google Trends data showed an approximately 10-fold increase in U.S. search interest for "silk fibroin" since 2023 (Figure 1). Conclusion: Preliminary evidence suggest silk fibroin dressings may reduce allergic contact across surgical closure. Evidence for long-term scar quality, barrier function, and infection remains limited (Figure 4). Multicenter randomized trials with standardized outcomes are needed.

Background: Oncoplastic breast surgery (OPS) is a form of breast conservation surgery (BCS) that has been shown to be a safe and effective treatment for breast cancer (1) (2). OPS includes both volume displacement (VD) and volume replacement (VR) techniques which allow for oncologic resection while preserving aesthetic outcomes (3). This study aims to evaluate advanced oncoplastic approaches that combine oncoplastic approaches using multiple pedicles and techniques to address complex reconstructive needs following BCS.

Methods: Patients undergoing OBS using at least dual pedicles were retrospectively reviewed from January 2023 to December 2025. Primary outcomes included oncologic safety and postoperative complication rates. Secondary outcomes included surgical complications, delay in adjuvant therapy, recurrence, mortality, and utilization of reconstructive techniques and adjunctive technologies.

Results: A total of 135 patients (139 breasts) underwent BCS with advanced oncoplastic reconstruction using at least a dual-pedicle technique. Median age was 59.0 years (IQR 51.5–66.0), and median body mass index was 30.1 kg/m² (IQR 26.0–35.0). Common comorbidities included hypertension (36.0%) and diabetes (8.6%). Median postoperative follow-up was 13.3 months (IQR 3.3–22.8). The most common primary cancer type was invasive ductal carcinoma (54.7%), followed by ductal carcinoma in situ (18.7%). Median tumor size was 1.5 cm (IQR 0.8–2.2). Positive margins occurred in 7.9% of cases, and 5.8% experienced a delay in adjuvant therapy. There were no cases of local recurrence or breast cancer–specific mortality during follow-up. One patient (0.7%) had evidence of metastatic disease, and all-cause mortality was 1.4%. Indications for advanced oncoplastic reconstruction included patient preference (51.1%), large area of disease or defect (28.8%), multicentric disease (10.1%), and tumor involvement of the nipple–areolar complex (NAC) (10.1%). Of the combined reconstructive approaches, the most frequently involved pedicle was the inferior pedicle in combination with another pedicle (66.2%). Sentinel lymph node biopsy was performed in 79.9% of patients. Adjunctive technologies included intraoperative indocyanine green angiography in 65.5% and closed incision negative pressure wound therapy in 96.4%. Overall postoperative complications occurred in 17.3% of patients, most commonly wound dehiscence (6.5%) and infection (5.8%). No cases of flap failure or nipple loss were observed.

Conclusion: Advanced oncoplastic breast surgery that combines multiple pedicles and techniques for reconstruction of complex defects are feasible and oncologically safe in selected patients undergoing BCS. These approaches address a range of indications, including large areas of disease, multicentric tumors, tumor involvement of the NAC, and patient preference, without compromising margin status or short-term oncologic outcomes. Complication rates were comparable to published outcomes, supporting the role of combined oncoplastic strategies in complex breast reconstruction.

1. Campbell EJ, Romics L. Oncological safety and cosmetic outcomes in oncoplastic breast conservation surgery, a review of the best level of evidence literature. Breast Cancer (Dove Med Press) 2017;9:521-30. 10.2147/BCTT.S113742

2. Chatterjee A, Gass J, Patel K, Holmes D, Kopkash K, Peiris L, Peled A, Ryan J, El-Tamer M, Reiland J. A Consensus Definition and Classification System of Oncoplastic Surgery Developed by the American Society of Breast Surgeons. Ann Surg Oncol. 2019 Oct;26(11):3436-3444. doi: 10.1245/s10434-019-07345-4. Epub 2019 Apr 11. PMID: 30977016.

3. De La Cruz L, Blankenship SA, Chatterjee A, et al. Outcomes After Oncoplastic Breast-Conserving Surgery in Breast Cancer Patients: A Systematic Literature Review. Ann Surg Oncol 2016;23:3247-58. 10.1245/s10434-016-5313-1

BACKGROUND Implant-based reconstruction remains the most common approach to post-mastectomy breast reconstruction. Advances in surgical technique have shifted reconstructive practice from the submuscular to the prepectoral plane; however, limited data exist regarding how implant characteristics have evolved during this transition. The purpose of this study was to assess temporal trends in implant volume and projection in the context of this paradigm shift. We hypothesized that the transition from submuscular to prepectoral implant placement would be associated with the use of smaller-volume, less-projected implants, based on the premise that the pectoralis muscle may partially obscure full device projection. METHODS A single institution retrospective review was performed of patients who underwent unilateral immediate two-stage implant-based reconstruction from January 2012 to December 2024. Trends in implant volume and projection, body mass index (BMI), as well as plane of implant placement, were analyzed across the study period. Multivariable analysis was used to assess the association of patient demographic, oncologic, and surgical characteristics, including plane of implant placement, on implant volume and projection over time. RESULTS Overall, 2,032 patients were included; 403 underwent prepectoral reconstruction, and 1,629 underwent submuscular reconstruction. The median age was 52 years, 44% of patients underwent neoadjuvant chemotherapy, and 24% underwent postoperative radiation. Between 2012 and 2018, submuscular implant placement was the predominant technique at the study institution. Prepectoral implant placement gained traction in 2018, and the number of cases with this technique continued to increase as the number of submuscular cases decreased. In mid to late 2021, prepectoral plane placement became the predominant technique. The average implant volume and projection were highest in 2016 (515 cc and 5.23 cm, respectively) and lowest in 2024 (424 cc and 4.74 cm, respectively). There was no concurrent trend in BMI observed during these years. Prepectoral implant placement was associated with smaller implant volume (Beta= -20, 95% CI: -38 to -3.1, p=0.021) and lower projection (Beta= -0.17, 95% CI: -.30 to -0.05, p=0.005) compared with submuscular placement. CONCLUSION Over a 12-year period, implant selection in breast reconstruction has trended toward smaller volumes and lower projections. Although these changes may reflect evolving aesthetic preferences, our analysis suggests that the plane of implant placement may also be an important explanatory factor. This study offers contemporary insight into reconstructive practice patterns and helps inform modern implant selection strategies.

Introduction: Delayed epithelialization of meshed skin grafts remains a major challenge in the treatment of full-thickness burns, particularly when limited donor skin necessitates high mesh ratios. Prolonged closure of mesh interstices increases the risk of infection, worsens patient outcomes, and increases healthcare costs. Keratinocyte migration is critical for epithelialization and is negatively regulated by β-adrenergic signaling [1-3]. Beta-blockers have been shown to enhance keratinocyte migration and improve wound healing in experimental models [2,4]; however, their efficacy in full-thickness burns reconstructed with meshed skin grafts has not been evaluated in a clinically relevant large-animal model. We therefore investigated the safety and efficacy of topical timolol in an ovine model of meshed autologous skin graft reconstruction following full-thickness burns.

Methods: Adult female Merino sheep underwent creation of six 25 cm² full-thickness flame burns on the dorsum. After 24 hours, eschars were excised and reconstructed with 4:1 meshed split-thickness autologous skin grafts (Day 0). Wounds were paired contralaterally and randomized to receive either topical timolol 0.5% (0.02 mL/cm²) or saline control, applied daily through Day 14. The epithelialization rates on Day 12, 13, and 14 were determined by planimetric analysis and compared using paired t-tests. Additionally, times to reach 85%, 90%, and 95% epithelialization were compared using survival time analysis with the log-rank test. Wound perfusion was measured using laser Doppler imaging and analyzed using two-way repeated-measures ANOVA followed by Bonferroni correction. Systemic hemodynamics and blood glucose levels were monitored to assess safety. At Day 14, histologic analysis and RT-qPCR were performed to evaluate epidermal thickness, inflammatory cell infiltration, angiogenesis, and expression of genes related to keratinocyte differentiation, TGFβ signaling, epithelial–mesenchymal transition, and myofibroblast activation. Histologic parameters and gene expression levels were compared using paired t-tests.

Results: All grafts healed without infection or hematoma. At Day 12, 13, and 14, epithelialization was significantly greater in the timolol-treated wounds compared with controls (68.88 ± 7.30% vs. 56.31 ± 6.52%, P = 0.0169 at Day 12, 76.84 ± 6.71% vs. 66.12 ± 6.06%, P = 0.0487 at Day 13, 84.46 ± 5.89% vs. 74.30 ± 5.86%, P = 0.0158 at Day 14). Time to reach 85%, 90%, and 95% epithelialization was significantly shorter in the timolol group (P = 0.0354, 0.0104, and 0.0313, respectively). Laser Doppler imaging demonstrated no differences in wound perfusion between groups at any time point. No systemic adverse effects were observed, including hypoglycemia, hypotension, or bradycardia. Histologically, epidermal thickness was greater in the timolol group (213.1 ± 15.6 µm vs. 183.5 ± 16.3 µm, P = 0.0203). Inflammatory cell counts (neutrophils, macrophages) and vessel density were similar between groups. RT-qPCR revealed no significant differences in transcriptional markers of proliferation (PCNA), keratinocyte differentiation (KRT1, KRT10), TGFβ signaling (TGFβ1, TGFβR1/2), epithelial–mesenchymal transition (VIM, FN1), or myofibroblast activation (COL1A1, COL3A1, ACTA2, MMP1).

Conclusions: Topical timolol significantly accelerates epithelialization of meshed autologous skin grafts in full-thickness burn wounds in a clinically relevant ovine model. The effect appears independent of changes in wound perfusion, inflammation, or transcriptional activation of TGFβ-, EMT-, or myofibroblast-related pathways, suggesting a mechanism distinct from angiogenic or proliferative modulation. Importantly, no systemic adverse effects were observed. Given its established safety profile, low cost, and widespread clinical availability, topical β-adrenergic blockade represents a promising adjunct to improve graft healing and potentially reduce complications associated with delayed epithelialization in burn reconstruction.

References: (1) Jia S, Wang X, Wang G, Wang X. Mechanism and application of β-adrenoceptor blockers in soft tissue wound healing. Med Res Rev. 2024;44(1):422-452. doi:10.1002/med.21984 (2) Sivamani RK, Pullar CE, Manabat-Hidalgo CG, et al. Stress-mediated increases in systemic and local epinephrine impair skin wound healing: potential new indication for beta blockers. PLoS Med. 2009;6(1):e12. doi:10.1371/journal.pmed.1000012 (3) Sarsik SM, El-Amawy HS. Uses of eye drops in dermatology, literature review. J Dermatolog Treat. 2022;33(6):2758-2770. doi:10.1080/09546634.2022.2079598 (4) Freiha M, Achim M, Gheban BA, Moldovan R, Filip GA. In Vivo Study of the Effects of Propranolol, Timolol, and Minoxidil on Burn Wound Healing in Wistar Rats. J Burn Care Res. 2023;44(6):1466-1477. doi:10.1093/jbcr/irad057