In Vivo Release of Zafirlukast from Electrospun Polyisobutylene-Based Fiber Mats to Reduce Capsular Contracture of Silicone Breast Prostheses.

Silicone rubber tissue expanders and breast implants are associated with chronic inflammation, leading to the formation of fibrous capsules. If the inflammation is left untreated, the fibrous capsules can become hard and brittle and lead to formation of capsular contracture. When capsular contracture occurs, implant failure and reoperation is unavoidable. Fibrous capsule formation to medical grade silicone rubber breast implants and polyisobutylene-based electrospun fiber mats attached to silicone rubber with and without an anti-inflammatory therapeutic were compared. A linear polyisobutylene (PIB)-based thermoplastic elastomer is currently applied as a polymer coating for drug release on coronary stents to reduce restenosis. Recent work has created a drug releasing electrospun fiber mat from PIB-based materials. Important to this study, poly(alloocimene-b-isobutylene-b-alloocimene) (AIBA) was electrospun with zafirlukast (ZAF). ZAF is an anti-inflammatory drug that is able to reduce capsule formation and complications to silicone breast implants. Fiber mats are advantageous for local drug delivery because of their high porosity and surface area for drug release. The chief hypothesis was that local release of ZAF from AIBA would lower inflammatory signaling and resulting capsular formation after 90 days in vivo. Electrospun AIBA mats locally released ZAF, lowering inflammation and fibrous capsule development compared to medical grade silicone rubber. Locally and orally released ZAF led to similar results, but the former had much lower concentration that highlights local delivery's therapeutic potential. Released ZAF from AIBA fiber mats mitigated inflammation and serves as an alternative to existing clinical approaches.

Leukotriene Inhibitors in the Prevention of Recurring Capsular Contracture in Secondary Breast Augmentation.

BACKGROUND: Capsular contracture (CC) remains a very common complication and the main cause of reoperation following a mammary implant surgery. Leukotrienes play an important role in the inflammatory cascade linked to the development of the periprosthetic capsule. The aim of this paper is to evaluate the incidence of recurrence of capsular contracture in female patients who underwent a secondary mammary augmentation due to this etiology, with and without treatment with leukotriene inhibitors during postoperative care. MATERIAL AND METHODS: Sixty-four women submitted to a secondary mammary augmentation due to CC were evaluated retrospectively. Out of these patients, 20 (31%) were treated with Montelukast for 3 months. The remaining 44 (69%) did not receive antileukotriene. The presence of capsular contracture was measured using the Baker classification and magnetic resonance imaging a year after postoperative care. The median follow-up period was 15 months. RESULTS: The patients receiving Montelukast (n = 20) presented a 15% CC rate (n = 1). The women that did not receive antileukotriene therapy (n = 44) presented a 16% CC rate (n = 7). CONCLUSION: The results of our study show that treatment with Montelukast for 3 months after the operation is associated with lower rates of capsular contracture when compared to patients that did not receive the treatment. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

A Histological Assessment Tool for Breast Implant Capsules Validated in 480 Patients with and Without Capsular Contracture.

BACKGROUND: Understanding the impact of breast implants on the histological response in the surrounding fibrous capsule is important; however, consensus is lacking on how to analyze implant capsules histologically. We aimed to develop a standardized histological assessment tool to be used in research potentially improving diagnostic accuracy and treatment strategies for capsular contracture. METHODS: Biopsies of breast implant capsules from 480 patients who had undergone breast augmentation or reconstruction were collected and stained with hematoxylin and eosin. Initially, biopsies from 100 patients were analyzed to select histological parameters demonstrating the highest relevance and reproducibility. Then, biopsies from the remaining 380 patients were used to determine intra- and interobserver agreements of two blinded observers and agreement with a pathologist. Finally, we tested the association between the parameters and capsular contracture. RESULTS: The histological assessment tool included ten parameters assessing the inflammatory, fibrotic, and foreign-body reaction to breast implants, each graded on two-, three-, or four-point scales. Intra- and interobserver agreements were almost perfect (0.83 and 0.80), and agreement with the pathologist was substantial (0.67). Four parameters were significantly correlated with capsular contracture, namely chronic inflammation with lymphocyte infiltration (p < 0.01), thickness of the collagen layer (p < 0.0001), fiber organization (p < 0.01), and calcification (p < 0.001). CONCLUSIONS: This is the first validated histological assessment tool for breast implant capsules. The validated tool not only advances our understanding of capsular contracture but also sets a new standard for histological evaluation in breast implant research and clinical diagnostics. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Surgical Management of Breast Capsular Contracture-A Multi-institutional Data Analysis of Risk Factors for Early Complications.

BACKGROUND: Capsular contracture (CC) is a common complication following implant-based breast surgery, often requiring surgical intervention. Yet, little is known about risk factors and outcomes following CC surgery. METHODS: We reviewed the American College of Surgeons National Surgical Quality Improvement Program database (2008-2021) to identify female patients diagnosed with CC and treated surgically. Outcomes of interest included the incidence of surgical and medical complications at 30-days, reoperations, and readmissions. Confounder-adjusted multivariable analyses were performed to establish risk factors. RESULTS: 5,057 patients with CC were identified (mean age: 55 ± 12 years and mean body mass index [BMI]: 26 ± 6 kg/m2). While 2,841 (65%) women underwent capsulectomy, capsulotomy was performed in 742 patients (15%). Implant removal and replacement were recorded in 1,160 (23%) and 315 (6.2%) cases, respectively. 319 (6.3%) patients experienced postoperative complications, with 155 (3.1%) reoperations and 99 (2.0%) readmissions. While surgical adverse events were recorded in 139 (2.7%) cases, 86 (1.7%) medical complications occurred during the 30 day follow-up. In multivariate analyses, increased BMI (OR: 1.04; p = 0.009), preoperative diagnosis of hypertension (OR: 1.48; p = 0.004), and inpatient setting (OR: 4.15; p < 0.001) were identified as risk factors of complication occurrence. CONCLUSION: Based on 14 years of multi-institutional data, we calculated a net 30 day complication rate of 6.3% after the surgical treatment of CC. We identified higher BMI, hypertension, and inpatient setting as independent risk factors of postoperative complications. Plastic surgeons may wish to integrate these findings into their perioperative workflows, thus optimizing patient counseling and determining candidates' eligibility for CC surgery. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Impact of post-operative infection on revision procedures in breast reconstruction: A marketscan database analysis.

BACKGROUND: Esthetic complications, such as capsular contracture and soft-tissue contour defects, hinder the desired outcomes of breast reconstruction. As subclinical infection is a prevailing theory behind capsular contracture, we investigated the effects of post-operative infections on these issues and revision procedures. METHODS: We conducted a retrospective database study (2007-2021) on breast reconstruction patients from the MarketScan® Databases. Esthetic complications were defined by their associated revision procedures and queried via CPT codes. Severe capsular contracture (Grade 3-4) was defined as requiring capsulotomy or capsulectomy with implant removal or replacement. Moderate and severe soft-tissue defects were determined by the need for fat grafting or breast revision, respectively. Generalized linear models were used, adjusting for comorbidities and surgical factors (p < 0.05). RESULTS: We analyzed the data on 62,510 eligible patients. Post-operative infections increased the odds of capsulotomy (OR 1.59, p < 0.001) and capsulectomy (OR 2.30, p < 0.001). They also raised the odds of breast revision for severe soft-tissue defects (OR 1.21, p < 0.001). There was no significant association between infections and fat grafting for moderate defects. Patients who had post-operative infections were also more likely to experience another infection after fat grafting (OR 3.39, p = 0.0018). In two-stage reconstruction, infection after tissue expander placement was associated with greater odds of infection after implant placement. CONCLUSION: Post-operative infections increase the likelihood of developing severe soft-tissue defects and capsular contracture requiring surgical revision. Our data reinforce the role of infections in the pathophysiology of capsular contracture. Additionally, infections elevate the risk of subsequent infections after fat grafting for moderate defects, further increasing patient morbidity.

Unveiling the Enigma: Exploring capsular contracture-Unraveling its link with autoimmune disorders and comprehensive examination of predisposing factors.

Introduction: Breast augmentation, a popular cosmetic surgery using devices like silicone implants, can lead to a common issue called capsular contracture (CC). This condition involves the formation of fibrous tissue around the implants and can be influenced by variables like immunological and bacterial factors. This study aimed to explore the impact of autoimmune diseases (ADs) on CC along with other factors influencing future clinical decisions. Methods: A systematic review of electronic databases was conducted using PubMed, Web of Science, Scopus, EMBASE, and involving adult patients (>18) with CC and ADs after breast surgery using MeSH terminology using a broad search strategy. All searches were performed and analyzed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, and duplicates were removed with Rayyan. Two independent investigators extracted and assessed the data involving demographics and baseline data related to CC and AD. Results: The incidence of CC varied (2.3%-4.1%). Subglandular placement and older device age raised risk. SERI Surgical Scaffold complications included necrosis, seroma, hematoma, implant loss, and infection; CC was associated with necrosis. Natrelle 410 implants showed lower 10-year CC risk than round gel implants. Acellular dermal matrix implant-based breast reconstruction with radiotherapy (RT) correlated with 20.7% post-RT CC. Previous research demonstrated no significant connection between silicone gel implants and ADs. Biofilm, surgical site infection, implant features, and interventions emerged as frequent CC risk factors. Conclusion: Finding appropriate techniques to reduce the risk factors associated with CC together with providing comprehensive patient counseling on these factors will definitely improve the patient-centered outcome of breast implant surgery.

Nonadherence of Polyurethane Implants: A Retrospective Cohort Study.

Background Biointegration of polyurethane (PU) implants providing their stable position years after surgery ensures predictable results of breast augmentation and reconstruction almost eliminating implant factor as a cause of complications. However, in rare cases PU implants appear to be not connected to the surrounding tissues. The aim of the study was to determine the incidence of PU implant nonadherence after primary breast augmentations and augmentation mastopexies with dual plane implant position, to analyze possible causes, and to propose preventive measures and treatment possibilities of this complication. Methods The results of primary aesthetic surgeries in 333 patients with dual plane PU implant placement were analyzed. Patients were evaluated clinically, and pictures and videos taken in different periods after the surgery were compared. Particular attention was given to the changes in implant position and the appearance of asymmetries over time. Results PU implant nonadherence was found in seven patients. It can be divided into primary and secondary and may be complete or partial. Primary nonadherence was found in two cases (0.6%), and secondary in five (1.5%) cases. Possible influencing factors could have been traumatic surgical technique, seroma, hematoma, or physical trauma. The average follow-up was 33 months (1 month-15 years). Conclusion Biointegration is mandatory for the long-term predictable results with PU implants. PU implant nonadherence leads to implant malposition and may cause typical complications connected to non-PU implants. Improvements in surgical maneuvers, manufacturing process, and weight reduction of the implant may be beneficial for the stability of the results. Level of Evidence V.

A Histological Evaluation of the Efficiency of Using Periprosthetic Autologous Fat to Prevent Capsular Contracture Compared to Other Known Methods-An Experimental Study.

BACKGROUND: Capsular contracture remains a common complication in silicone breast implantation. The etiology, formation mechanisms, predisposing and favoring factors are still subjects of research. This study aims to demonstrate the effectiveness of using autologous fat introduced periprosthetically in preventing capsular contracture compared to other known methods: antibiotics and corticosteroids. METHODS: A cohort of 80 Wistar rats was included in the study, divided into four subgroups. All subjects received a silicone implant, implanted in a pocket created along the abdominal midline. The first subgroup served as the control group, with subjects having the implant placed without any treatment. For the second and third subgroups, the implants were treated with an antibiotic solution and intramuscular injections of dexamethasone, respectively. The subjects in the last subgroup received centrifuged autologous fat introduced periprosthetically. RESULTS: The subgroup with autologous fat exhibited a significantly smaller capsule thickness, which was poorly represented, with a smooth surface. The use of autologous fat for treating silicone prosthesis was linked with the lack of acute inflammation around the prosthetic site. CONCLUSIONS: Autologous fat helps to minimize the "non-self" reaction, which results in the development of a periprosthetic capsule consisting of mature collagen fibers interspersed with adipocytes.

A Grading System-Guided Approach to the Severely Contracted Nose.

PURPOSE: Capsular contracture is a rare but serious complication of silicone implant-based augmentation rhinoplasty. When severe, the contracture can affect all layers of the nose, causing significant scarring and disfigurement. There is currently no standardized method of evaluating contracted noses and a paucity of literature on the treatment of severe contracture. Therefore, this study aimed to establish a comprehensive grading system and treatment approach for patients with nasal contracture secondary to silicone implant-based rhinoplasty. METHODS: We conducted a retrospective analysis on patients who presented with nasal contracture from 2012 to 2021. All preoperative photographs were evaluated by two plastic surgeons, twice at 1-month intervals. The proposed grading system comprised: normal (grade I), mild contracture with detectable implant (grade II), moderate contracture with skin thinning (grade III), severe contracture with short nose deformity (grade IV), and destructive contracture with scarring of the dorsal skin (grade Va), or columella deficiency (grade Vb). Inter- and intraobserver agreement was assessed using the kappa value to determine the reliability of the system. RESULTS: Based on 87 patients, interobserver agreement was substantial for both evaluation time points (k = 0.701 and 0.723). Intraobserver agreement was excellent for evaluator 1 (k = 0.822) and substantial for evaluator 2 (k = 0.699). CONCLUSIONS: Using this grading system, we propose a graduated treatment algorithm for contracted noses. Most notable is our use of radial forearm free or forehead flaps to reconstruct the columella in grade Vb patients. By combining reconstructive and aesthetic principles, this treatment approach provides an effective and elegant solution for the management of the severely contracted nose. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Efficacy of antibiotic prophylaxis for reducing capsular contracture in prosthesis-based breast surgery: a systemic review and meta-analysis.

Antibiotics Prophylaxis to prevent capsular contracture in prosthesis-based breast surgery is common in clinical practice. However, there is currently a dearth of high-quality evidence concerning the effectiveness of antibiotic usage in this field. To identify all pertinent studies prior to January 2023, a comprehensive literature search was conducted in the PubMed, Embase, Web of Science, Cochrane Library, and Medline databases. The extracted data was then subjected to meta-analysis. Fourteen studies were retained in the analysis. According to the results, perioperative antibiotic prophylaxis did not reduce the risk of capsular contracture (RR 1.15, 95% CI 0.82-1.59, p = 0.55) or surgical-site infection (RD 0.01, 95% CI - 0.01 to 0.03, p = 0.59) compared to nonantibiotic prophylaxis. There was no statistically significant difference between extended antibiotic prophylaxis and perioperative antibiotic prophylaxis in terms of preventing capsular contracture, whether calculated by patient numbers (RD 0.01, 95% CI - 0.01 to 0.02, p = 0.87) or by total procedures (RD 0.00, 95% CI - 0.00 to 0.01, p = 0.88), or controlling surgical-site infection (RR 1.05, 95% CI 0.77-1.44, p = 0.27). Additionally, topical antibiotic irrigation did not decrease the risk of infection (RR 0.61, 95% CI 0.34-1.08, p = 0.29) and capsular contracture, regardless of patient number (RR 0.41, 95% CI 0.27-0.63, p = 0.18) or total number of procedures (RR 1.29, 95% CI 0.73-2.28, p < 0.01). Current evidence revealed that both systemic and topical antibiotic prophylaxis may not provide benefits in preventing capsular contracture in prosthesis-based breast surgery. When the occurrence of surgical-site infections is minimized to the greatest extent, the administration of additional antibiotics for reducing capsular contracture should be carefully and judiciously considered.

Incidence and Risk Assessment of Capsular Contracture in Breast Cancer Patients following Post-Mastectomy Radiotherapy and Implant-Based Reconstruction.

Our study aims to identify the risk factors and dosimetry characteristics associated with capsular contracture. METHODS: We retrospectively analyzed 118 women with breast cancer who underwent PMRT following an IBR between 2010 and 2022. Patients were treated with PMRT of 50.0-50.4 Gy in 25-28 fractions. Capsular contracture was categorized according to the Baker Classification for Reconstructed Breasts. RESULTS: After a median follow-up of 22 months, the incidence of clinically relevant capsular contracture (Baker III-IV) was 22.9%. Overall, capsular contracture (Baker I-IV) occurred in 56 patients (47.5%) after a median of 9 months after PMRT. The rate of reconstruction failure/implant loss was 25.4%. In the univariate analysis, postoperative complications (prolonged pain, prolonged wound healing, seroma and swelling) and regional nodal involvement were associated with higher rates of capsular contracture (p = 0.017, OR: 2.5, 95% CI: 1.2-5.3 and p = 0.031, respectively). None of the analyzed dosimetric factors or the implant position were associated with a higher risk for capsular contracture. CONCLUSION: Postoperative complications and regional nodal involvement were associated with an increased risk of capsular contracture following breast reconstruction and PMRT, while none of the analyzed dosimetric factors were linked to a higher incidence. Additional studies are needed to identify further potential risk factors.

Transcriptomic and machine learning analyses identify hub genes of metabolism and host immune response that are associated with the progression of breast capsular contracture.

Capsular contracture is a prevalent and severe complication that affects the postoperative outcomes of patients who receive silicone breast implants. At present, prosthesis replacement is the major treatment for capsular contracture after both breast augmentation procedures and breast reconstruction following breast cancer surgery. However, the mechanism(s) underlying breast capsular contracture remains unclear. This study aimed to identify the biological features of breast capsular contracture and reveal the potential underlying mechanism using RNA sequencing. Sample tissues from 12 female patients (15 breast capsules) were divided into low capsular contracture (LCC) and high capsular contracture (HCC) groups based on the Baker grades. Subsequently, 41 lipid metabolism-related genes were identified through enrichment analysis, and three of these genes were identified as candidate genes by SVM-RFE and LASSO algorithms. We then compared the proportions of the 22 types of immune cells between the LCC and HCC groups using a CIBERSORT analysis and explored the correlation between the candidate hub features and immune cells. Notably, PRKAR2B was positively correlated with the differentially clustered immune cells, which were M1 macrophages and follicular helper T cells (area under the ROC = 0.786). In addition, the expression of PRKAR2B at the mRNA or protein level was lower in the HCC group than in the LCC group. Potential molecular mechanisms were identified based on the expression levels in the high and low PRKAR2B groups. Our findings indicate that PRKAR2B is a novel diagnostic biomarker for breast capsular contracture and might also influence the grade and progression of capsular contracture.

Fatores de risco consequentes a complicações no pósoperatório da mastoplastia de aumento primária com implantes de silicone: Estudo retrospectivo / Risk factors resulting from complications in the postoperative period of primary breast augmentation with silicone implants: Retrospective study

Introdução: A mamoplastia de aumento é uma das cirurgias plásticas mais realizadas no mundo. Tendo em vista sua alta aplicabilidade, é fundamental conhecer os fatores de risco relacionados à incidência de complicações pós-operatórias a fim de reduzilas nesse tipo de procedimento. Método: Este estudo é retrospectivo feito por meio da análise dos prontuários de 76 pacientes que realizaram mamoplastia de aumento primária com implantes de silicone durante os meses de janeiro de 2018 a dezembro de 2020. Resultados: Observou-se que a presença de comorbidades aumentou a incidência de complicações pós-operatórias precoces (p<0,001), mas não de complicações pósoperatórias tardias (p=0,8). O maior tempo cirúrgico também aumentou a incidência de complicações pós-operatórias (p=0,005). Conclusão: A presença de comorbidades influencia diretamente na incidência de complicações pós-operatórias da mastoplastia de aumento e por esta razão deve-se realizar uma adequada compensação pré-operatória antes de submeter as pacientes a este procedimento cirúrgico.

Introduction: Breast augmentation is one of the most performed plastic surgeries in the world. Given its high applicability, it is essential to know the risk factors related to the incidence of postoperative complications to reduce them in this type of procedure. Method: This retrospective study analyzed the medical records of 76 patients who underwent primary breast augmentation with silicone implants from January 2018 to December 2020. Results: It was observed that the presence of comorbidities increased the incidence of early postoperative complications (p<0.001) but not of late postoperative complications (p=0.8). Longer surgical time also increased the incidence of postoperative complications (p=0.005). Conclusion: The presence of comorbidities directly influences the incidence of postoperative complications after breast augmentation, and for this reason, adequate preoperative compensation must be carried out before submitting patients to this surgical procedure.

Implant-based breast surgery and capsular formation: when, how and why?-a narrative review.

Background and Objective: Implant-based breast surgery is a common procedure for both reconstructive and aesthetic purposes. Breast implants, like any foreign object, trigger the formation of a capsule around them. While generally harmless, the capsule can undergo fibrotic changes leading to capsular contracture, which can negatively impact surgical outcomes and patient well-being. Additionally, rare but serious complications, such as breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) and capsule-associated squamous cell carcinoma, have been reported. This paper aims to review the physiology of capsular formation, identify factors contributing to capsule-related pathologies, and discuss their clinical implications. Methods: A review of relevant literature was conducted by searching databases for articles published between inception and September 2022. The search included but not limited to terms such as "capsular formation" and "capsular contracture". Selected articles were critically analyzed to address the objectives of this review. Key Content and Findings: Capsular formation involves interactions between the implant surface, surrounding tissues, and the immune system. Factors influencing pathological changes in the capsule include genetic predisposition, bacterial contamination, implant characteristics, and surgical techniques. Capsular contracture, characterized by tissue hardening, pain, and implant distortion, remains the most common complication. Rare but life-threatening conditions, such as BIA-ALCL and capsule-associated squamous cell carcinoma, necessitate vigilant monitoring and early detection. Conclusions: Understanding the physiology of capsular formation and its associated pathologies is crucial for healthcare providers involved in implant-based breast surgery. Efforts should focus on minimizing the risk of capsular contracture through improved implant materials, surgical techniques, and infection prevention. The emergence of BIA-ALCL and capsule-associated squamous cell carcinoma underscores the importance of long-term surveillance and prompt diagnosis. Further research is needed to uncover underlying mechanisms and develop preventive measures and treatments for these complications. Enhancing our knowledge and clinical management of capsular formation will lead to safer and more successful outcomes in implant-based breast surgery.

Activin A and Follistatin Serum Concentrations in Breast Augmentation Patients.

Background: Capsular contracture is caused by an excessive fibrotic reaction similar as observed in other progressive fibrotic disorders. For their pathogenesis, several studies confirmed the importance of activins and follistatin. The aim of this study was to determine and analyze serum levels of Activin A and follistatin in patients with capsular contracture after aesthetic breast augmentation. Methods: The study included 361 female patients who underwent primary aesthetic breast augmentation, came for control examination after breast augmentation or for revision operation because of capsular contracture. Blood samples were taken and using a specific ELISA to determine the serum concentration levels of Activin A and Follistatin. Results: Ninety-six patients (n = 96), who developed a capsular contracture Baker ≥°III and underwent revision surgery were collected (capsular fibrosis group). One-hundred and fourteen patients (n = 114) were asymptomatic for capsular fibrosis Baker ≥°III after primary breast augmentation and 33 (n = 33) of them had developed no capsular fibrosis after more than 10 years (long-term group). For control group, blood samples were taken from 167 patients (n = 167) before primary aesthetic breast augmentation. Serum Activin A levels were significantly higher in the long-term Group compared with those in the capsular fibrosis- and the control groups. Follistatin levels were significantly lower in the capsular fibrosis group compared to the control- and the long-term groups. A small amount of control group patients (n = 16) developed a capsular fibrosis within 2 years after primary breast augmentation with significant lower follistatin levels. Retrospectively, they showed significantly lower serum follistatin levels than the control group even before the onset of capsular contracture. Conclusions: Capsular fibrosis has no effect on Activin A serum levels. In contrast, follistatin serum levels are lower in patients with capsular fibrosis. These results show that besides many other factors, a dysregulation of the Activin-follistatin axis may have importance on the pathogenesis of capsular contracture.

Contexte : Une coque est causée par une réaction fibreuse excessive semblable à celle observée dans d'autres troubles fibreux évolutifs. Plusieurs études ont confirmé l'importance des activines et de la follistatine dans leur pathogénie. L'objectif de cette étude était de déterminer et d'analyser les taux sériques d'activine A et de follistatine chez des patientes présentant une coque après augmentation mammaire à but esthétique. Méthodes : L'étude a inclus 361 patientes qui avaient subi une augmentation mammaire primaire dans un but esthétique et qui étaient venues pour un examen de contrôle en vue d'une intervention de révision pour cause de coque. Des échantillons de sang ont été prélevés et analysés en utilisant un test ELISA spécifique afin de déterminer les concentrations sériques d'activine A et de follistatine. Résultats : Quatre-vingt-seize patientes (n = 96) ayant développé une coque Baker ≥°III et ayant bénéficié d'une chirurgie de révision ont été identifiées (groupe coque fibreuse). Cent quatorze patientes (n = 114) étaient asymptomatiques pour une fibrose capsulaire Baker ≥°III après l'augmentation mammaire primitive et, parmi elles, trente-trois (n = 33) n'avaient pas développé de coque après plus de 10 ans (groupe à long terme). Des prélèvements de sang ont été effectués sur un groupe témoin de 167 patientes avant l'augmentation mammaire primaire à visée esthétique. Les taux sériques d'activine A étaient significativement plus élevés dans le groupe à long terme, comparativement au groupe coque fibreuse et au groupe contrôle. Les taux de follistatine ont été significativement plus faibles dans le groupe coque fibreuse comparativement au groupe contrôle et au groupe à long terme. Un petit nombre de patientes du groupe contrôle (n = 16) ont développé une coque fibreuse dans les deux ans suivant l'augmentation mammaire primitive avec des taux de follistatine significativement plus faibles. De façon rétrospective, leurs taux sériques de follistatine étaient significativement plus faibles que dans le groupe contrôle, même avant l'apparition de la coque. Conclusions : La coque fibreuse n'a pas d'effet sur les taux sériques d'activine A. En revanche, les taux sériques de follistatine sont plus faibles chez les patientes ayant une coque. Ces résultats montrent qu'en plus de nombreux autres facteurs, une dérégulation de l'axe activine A-follistatine peut avoir de l'importance pour la pathogénie de la coque.

In vitro models of soft tissue damage by implant-associated frictional shear stresses.

Silicone elastomer medical implants are ubiquitous in medicine, particularly for breast augmentation. However, when these devices are placed within the body, disruption of the natural biological interfaces occurs, which significantly changes the native energy-dissipation mechanisms of living systems. These new interfaces can introduce non-physiological contact pressures and tribological conditions that provoke inflammation and soft tissue damage. Despite their significance, the biotribological properties of implant-tissue and implant-extracellular matrix (ECM) interfaces remain poorly understood. Here, we developed an in vitro model of soft tissue damage using a custom-built in situ biotribometer mounted onto a confocal microscope. Sections of commercially-available silicone breast implants with distinct and clinically relevant surface roughness (Ra = 0.2 ± 0.03 µm, 2.7 ± 0.6 µm, and 32 ± 7.0 µm) were mounted to spherically-capped hydrogel probes and slid against collagen-coated hydrogel surfaces as well as healthy breast epithelial (MCF10A) cell monolayers to model implant-ECM and implant-tissue interfaces. In contrast to the "smooth" silicone implants (Ra < 10 µm), we demonstrate that the "microtextured" silicone implant (10 < Ra < 50 µm) induced higher frictional shear stress (τ > 100 Pa), which led to greater collagen removal and cell rupture/delamination. Our studies may provide insights into post-implantation tribological interactions between silicone breast implants and soft tissues.

Prevalence of risk factors associated with development of capsular contracture after placement of breast implants.

OBJECTIVE: To determinate the prevalence of the main risk factors associated with development of capsular contracture after placement of breast implants in a referral center. METHOD: Retrospect study on 210 patients where sociodemographic variables, Baker's clinical scale and histopathological results were recorded. RESULTS: Statistical analysis of 210 patients was performed; 98.1% were women. The average age was 47 years (± 11), body mass index 25 (± 10) and onset of symptoms 13 years (± 8.5). Sociodemographic factors: domestic work 63.3%. Alcoholism 70% and smoking 65.7%. The main reason for consultation was pain plus deformity in 81.6%. The risk factors with statistical significance were the history of trauma, with 83.3% (p = 0.004), and the subglandular plane, with 73.8% (p = 0.0115). Histopathology: fibrous capsule 81.4%. CONCLUSIONS: The prevalence of the risk factors described are similar to those reported in the literature. Only for the history of trauma and the subglandular plane there was statistical significance.

OBJETIVO: Determinar la prevalencia de los principales factores de riesgo asociados a contractura capsular posterior a mamoplastia de aumento en un centro de referencia. MÉTODO: Estudio retrospectivo de 210 pacientes en el que se registraron variables sociodemográficas, escala clínica de Baker y resultados histopatológicos. RESULTADOS: Se realizó el análisis estadístico de 210 pacientes; el 98.1% fueron mujeres. La edad promedio fue de 47 años (± 11), el índice de masa corporal 25 kg/m2 (± 10) y el inicio de los síntomas 13 años (± 8.5). Factores sociodemográficos: labores domésticas 63.3%. Alcoholismo 70% y tabaquismo 65.7%. El principal motivo de consulta fue dolor más deformidad, en el 81.6%. Los factores de riesgo con significancia estadística fueron el antecedente de traumatismo, con un 83.3% (p = 0.004), y el plano subglandular, con un 73.8% (p = 0.0115). Histopatología: cápsula fibrosa 81.4%. CONCLUSIONES: La prevalencia de los factores de riesgo descritos es similar a lo reportado en la literatura. Solo para el antecedente de traumatismo y el plano subglandular hubo significancia estadística.

Non-surgical Treatment of Capsular Contracture by Overfilling a Spectrum™ Saline Implant.

Capsular contracture is one of the most common complications following breast implant use in both aesthetic and reconstructive surgery procedures. Furthermore, capsular contracture remains one of the most common causes of reoperation in these patients. Therefore, it is important to identify and explore new treatment options to alleviate the risks associated with surgery as well as the financial burden of reoperation. We present a case of successful nonsurgical treatment of capsular contracture by overfilling a Spectrum™ adjustable saline implant followed by volume reduction. A 53-year-old patient was examined in our clinic post bilateral mastectomy and immediate reconstruction adjustable Spectrum™ saline implants in the subglandular plane. Two years postoperatively, the patient presented with Grade III capsular contracture in her right breast. Treatment was administered by overfilling the 275cc implant with 250cc in the right breast to rupture the capsule. The implant was kept overexpanded for a total of 14 days. The volume was subsequently reduced with optimal patient satisfaction. The patient has not had a reoccurrence of capsular contracture in one year. The treatment of capsular contracture by overfilling and temporarily overexpanding a Spectrum™ adjustable saline is a promising technique that warrants further investigation.

Machine-Learning Prediction of Capsular Contraction after Two-Stage Breast Reconstruction.

Background: Two-stage breast reconstruction is a common technique used to restore preoperative appearance in patients undergoing mastectomy. However, capsular contracture may develop and lead to implant failure and significant morbidity. The objective of this study is to build a machine-learning model that can determine the risk of developing contracture formation after two-stage breast reconstruction. Methods: A total of 209 women (406 samples) were included in the study cohort. Patient characteristics that were readily accessible at the preoperative visit and details pertaining to the surgical approach were used as input data for the machine-learning model. Supervised learning models were assessed using 5-fold cross validation. A neural network model is also evaluated using a 0.8/0.1/0.1 train/validate/test split. Results: Among the subjects, 144 (35.47%) developed capsular contracture. Older age, smaller nipple-inframammary fold distance, retropectoral implant placement, synthetic mesh usage, and postoperative radiation increased the odds of capsular contracture (p < 0.05). The neural network achieved the best performance metrics among the models tested, with a test accuracy of 0.82 and area under receiver operative curve of 0.79. Conclusion: To our knowledge, this is the first study that uses a neural network to predict the development of capsular contraction after two-stage implant-based reconstruction. At the preoperative visit, surgeons may counsel high-risk patients on the potential need for further revisions or guide them toward autologous reconstruction.

Difference in the outcomes of anterior tenting and wrapping techniques for acellular dermal matrix coverage in prepectoral breast reconstruction.

BACKGROUND: Acellular dermal matrices (ADMs) play an essential role in prepectoral implant-based breast reconstructions; however, the most appropriate method for ADMs is unknown. METHODS: We conducted a retrospective analysis of our institutional database. Patients who underwent mastectomy and prepectoral breast reconstruction using tissue expanders or breast implants covered with ADMs between March 2018 and June 2021 were included. Patient characteristics, postoperative complications, and long-term outcomes were investigated. RESULTS: In total, 112 patients (126 breasts) were included. The anterior tenting and wrapping techniques were used in the reconstruction of 32 (25.3%) and 94 (74.7%) breasts, respectively. Using propensity score matching, nine breasts were selected for each technique within the direct-to-implant reconstruction group, while 16 breasts were selected for each technique within the 2-stage reconstruction group. The choice of technique (anterior vs. wrapping) in implementing ADM did not generate any significant differences in postoperative complications, including seroma formation and capsular contracture, for the direct-to-implant and 2-stage reconstruction groups. Regarding the direct-to-implant reconstruction group, the average postoperative drain volume was less in the anterior tenting group than that in the wrapping group (anterior tenting vs. wrapping; 495.09 ± 156.118 mL vs. 673.43 ± 307.954 mL, p = 0.006), but the difference was insignificant after propensity score matching. CONCLUSION: We report our experience with covering prosthetic devices with ADMs during postmastectomy breast reconstruction. No differences in the postoperative drain volume or postoperative outcomes were found between the study groups. Future studies are needed to determine the method that provides the most satisfactory results.