Bacterial colonization is of major relevance for high-grade capsular contracture after augmentation mammaplasty

Biologic Response With and Without Acellular Dermal Matrix in Breast Reconstruction

Background

Acellular dermal matrices (ADMs) are biologic meshes commonly used in implant-based breast reconstruction (IBBR) procedures to provide implant support and coverage. Although the etiology is not well understood, increasing preclinical and clinical evidence suggest that ADMs may help prevent capsular contracture, a frequent complication of IBBR, by modulating the inflammatory response in the tissue surrounding breast implants. The objective of this narrative review is to discuss the evidence supporting the role of inflammation in capsular contracture following IBBR without ADM, and to characterize the potential mechanism(s) by which ADMs may reduce the incidence of capsular contracture in IBBR.

Methods

Relevant studies in English published up to December 31, 2023, were identified from 4 databases (BIOSIS Previews, Embase, MEDLINE, and Northern Light Life Sciences Conference Abstracts) using search terms such as "breast" and "capsular contracture."

Results

This review discusses the potential factors (eg, expander-to-implant reconstruction, diminished collagen integrity, postmastectomy radiation therapy, surface of implant, plane of placement, incision type, hematoma, seroma, postoperative infection, and biofilm) and emerging biomarkers (eg, NRG1, IL-8, TIMP-1, TIMP-2, TIMP-4, MMP2, MMP12, ACAN, SAA1, TNFSF11, and hyaluronan) that may be able to predict capsular contracture. The available evidence that tissue integration of ADMs modulates the wound healing process and inflammation, and the available clinical evidence, which indicates that ADMs may decrease rates of capsular contracture following postmastectomy radiation therapy, are summarized.

Conclusions

The studies summarized in this review suggest that ADMs may reduce the likelihood of capsular contracture in IBRR compared with no ADM use.

A Comparison of Ovine-Reinforced Hybrid Mesh (OviTex PRS) With Porcine Acellular Dermal Matrix (STRATTICE) in the Treatment of Advanced Breast Implant Capsular Contracture

Background

Tissue reinforcement techniques with porcine acellular dermal matrices (ADMs) have been widely adopted as standard care in treating capsular contracture. However, the application of alternative xenograft or mesh materials has not been widely studied.

Objectives

To examine the efficacy of OviTex PRS Reinforced Tissue Matrix (Resorbable) (TELA Bio, Malvern, PA), a hybrid ovine-reinforced mesh, in comparison with STRATTICE Reconstructive Tissue Matrix (Allergan, Irvine, CA), in patients with advanced capsular contracture.

Methods

A retrospective review was conducted on patients who underwent breast revision surgery for Baker Grade III or IV capsular contracture. Patient data were reviewed for outcomes, complications, cost, and postoperative incidence of recurrent capsular contracture after treatment with each specific mesh.

Results

Fifty-nine of 89 breasts (66.3%) were treated with OviTex and 30 (33.7%) were treated with STRATTICE. All patients experienced a reduction in Baker grades. In patients treated with OviTex, 96.6% (n = 57) of breasts had a postoperative Baker Grade I with the remaining 3.4% (n = 2) breasts presenting with a Baker Grade II. In comparison, 73.3% (n = 22), 23.3% (n = 7), and 3.3% (n = 1) of the STRATTICE cohort presented with Baker Grades I, II, and III, respectively. This demonstrated a statistically significant improvement in Baker grade capsular contracture in the OviTex cohort (P < .05) compared with STRATTICE. Average cost was $27.37/cm2 for STRATTICE compared with $22.28/cm2 for OviTex PRS.

Conclusions

OviTex may be successfully utilized to treat capsular contracture. Patient outcomes may be superior to STRATTICE in recurrent capsular contracture, particularly when a previous ADM had been utilized. Cost data show improved savings with the use of OviTex compared with STRATTICE.

Level of Evidence 3

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.

Systematic Review of Capsular Contracture Management following Breast Augmentation: An Update

BACKGROUND

Capsular contracture is one of the most frequent indications for revision following breast augmentation. Management goals focus on restoring breast aesthetics and minimizing subsequent recurrence of capsular contracture. As new data emerge, close review of the data are merited to build evidence-based clinical guidelines to inform surgical practice and management of capsular contracture.

METHODS

A systematic review of the MEDLINE, Embase, and Cochrane Database of Systematic Reviews databases was conducted to characterize the surgical management of capsular contracture in revision breast augmentations. The primary endpoint was capsular contracture recurrence rate.

RESULTS

The review was conducted in November of 2021. Primary search revealed 14,163 results. Initial screening by title left 1223 articles. Abstract review left 90 articles for full-text review, of which 34 were ultimately included and were all observational in nature.

CONCLUSIONS

Capsular contracture management remains an important topic, with limited high-level evidence for establishing clear evidence-based treatment guidelines. Although more evidence is required to assess the effects of capsulectomy, implant exchange, and plane change, these appear to be useful mechanisms for reducing recurrent capsular contracture. There is more evidence regarding the use of acellular dermal matrix, although this still requires long-term follow-up studies. New developments regarding textured implants limit the revision breast augmentation surgeon to smooth devices.

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.

Matrix Metalloproteinase-9 as a Potential Biomarker in 631 Human Implant-Induced Fibrotic Capsules: Analysis and Biomarker Study

BACKGROUND

Capsular fibrosis (CF) often occurs around biomedical devices following implantation causing pain, discomfort, and device failure. Breast implantation remains among the most common medical procedures worldwide. Revealing specific genes that drive fibrotic deposition will help us to garner a better understanding of the pathophysiology of this disease and develop different strategies to combat it.

METHODS

The authors collected 631 capsules around breast implants and were able to connect clinical baseline characteristics with histopathologic findings. In addition, the authors were able to conduct the first large systematic analysis to identify differentially expressed genes in fibrotic human tissue samples, comparing the lowest form of fibrosis with the most aggravated one.

RESULTS

The authors identified 2559 differentially expressed genes on which they performed a knowledge-based network generation and pathway association study to identify putative novel biomarkers for CF. The authors were able to show changes of cellular influx during progression of CF and distinguish several genes as potential clinical biomarkers and drug targets. Among these, matrix metalloproteinase-9 was one of the most up-regulated ( P = 0.006) and is attractive because of its wide detectability.

CONCLUSIONS

Matrix metalloproteinase-9 seems to be a potential biomarker to detect capsular fibrosis. It is a measurable indicator that can easily be detected in blood, sputum, and urine. For the diagnosis of fibrosis, this biomarker might be exceedingly beneficial to developing novel screening methods and prophylaxes.

CLINICAL RELEVANCE STATEMENT

Discovering biomarkers at the earliest and mildest stages for the diagnosis of fibrosis is clinically important. These results bring new hope for biomarker-based diagnosis for capsular fibrosis.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Diagnostic, V.

An Experimental Murine Model to Assess Biofilm Persistence on Commercial Breast Implant Surfaces

Capsular contracture is the most frequently associated complication following breast implant placement. Biofilm formation on the surface of such implants could significantly influence the pathogenesis of this complication. The objective of this study was to design an experimental model of breast implant infection that allowed us to compare the in vivo S. epidermidis ability to form and perpetuate biofilms on commonly used types of breast implants (i.e., macrotexturized, microtexturized, and smooth). A biofilm forming S. epidermidis strain (ATCC 35984) was used for all experiments. Three different implant surface types were tested: McGhan BIOCELL® (i.e., macrotexturized); Mentor Siltex® (i.e., microtexturized); and Allergan Natrelle Smooth® (i.e., smooth). Two different infection scenarios were simulated. The ability to form biofilm on capsules and implants over time was evaluated by quantitative post-sonication culture of implants and capsules biopsies. This experimental model allows the generation of a subclinical staphylococcal infection associated with a breast implant placed in the subcutaneous tissue of Wistar rats. The probability of generating an infection was different according to the type of implant studied and to the time from implantation to implant removal. Infection was achieved in 88.9% of macrotextured implants (i.e., McGhan), 37.0% of microtexturized implants (i.e., Mentor), and 18.5% of smooth implants (i.e., Allergan Smooth) in the short-term (p < 0.001). Infection was achieved in 47.2% of macrotextured implants, 2.8% of microtexturized implants, and 2.8% of smooth implants (i.e., Allergan Smooth) in the long-term (p < 0.001). There was a clear positive correlation between biofilm formation on any type of implant and capsule colonization/infection. Uniformly, the capsules formed around the macro- or microtexturized implants were consistently macroscopically thicker than those formed around the smooth implants regardless of the time at which they were removed (i.e., 1−2 weeks or 3−5 weeks). We have shown that there is a difference in the ability of S epidermidis to develop in vivo biofilms on macrotextured, microtextured, and smooth implants. Smooth implants clearly thwart bacterial adherence and, consequently, biofilm formation and persistence are hindered.

Pharmacological Approaches for the Prevention of Breast Implant Capsular Contracture

Capsular contracture is a common complication associated with breast implants following reconstructive or aesthetic surgery in which a tight or constricting scar tissue capsule forms around the implant, often distorting the breast shape and resulting in chronic pain. Capsulectomy (involving full removal of the capsule surrounding the implant) and capsulotomy (where the capsule is released and/or partly removed to create more space for the implant) are the most common surgical procedures used to treat capsular contracture. Various structural modifications of the implant device (including use of textured implants, submuscular placement of the implant, and the use of polyurethane-coated implants) and surgical strategies (including pre-operative skin washing and irrigation of the implant pocket with antibiotics) have been and/or are currently used to help reduce the incidence of capsular contracture. In this article, we review the pharmacological approaches-both commonly practiced in the clinic and experimental-reported in the scientific and clinical literature aimed at either preventing or treating capsular contracture, including (i) pre- and post-operative intravenous administration of drug substances, (ii) systemic (usually oral) administration of drugs before and after surgery, (iii) modification of the implant surface with grafted drug substances, (iv) irrigation of the implant or peri-implant tissue with drugs prior to implantation, and (v) incorporation of drugs into the implant shell or filler prior to surgery followed by drug release in situ after implantation.

Functionalized Self-Assembled Monolayers: Versatile Strategies to Combat Bacterial Biofilm Formation

Bacterial infections due to biofilms account for up to 80% of bacterial infections in humans. With the increased use of antibiotic treatments, indwelling medical devices, disinfectants, and longer hospital stays, antibiotic resistant infections are sharply increasing. Annual deaths are predicted to outpace cancer and diabetes combined by 2050. In the past two decades, both chemical and physical strategies have arisen to combat biofilm formation on surfaces. One such promising chemical strategy is the formation of a self-assembled monolayer (SAM), due to its small layer thickness, strong covalent bonds, typically facile synthesis, and versatility. With the goal of combating biofilm formation, the SAM could be used to tether an antibacterial agent such as a small-molecule antibiotic, nanoparticle, peptide, or polymer to the surface, and limit the agent’s release into its environment. This review focuses on the use of SAMs to inhibit biofilm formation, both on their own and by covalent grafting of a biocidal agent, with the potential to be used in indwelling medical devices. We conclude with our perspectives on ongoing challenges and future directions for this field.

Environmental, Microbiological, and Immunological Features of Bacterial Biofilms Associated with Implanted Medical Devices

The spread of biofilms on medical implants represents one of the principal triggers of persistent and chronic infections in clinical settings, and it has been the subject of many studies in the past few years, with most of them focused on prosthetic joint infections. We review here recent works on biofilm formation and microbial colonization on a large variety of indwelling devices, ranging from heart valves and pacemakers to urological and breast implants and from biliary stents and endoscopic tubes to contact lenses and neurosurgical implants. We focus on bacterial abundance and distribution across different devices and body sites and on the role of environmental features, such as the presence of fluid flow and properties of the implant surface, as well as on the interplay between bacterial colonization and the response of the human immune system.

Diagnosis, management, and outcome of urethral obstruction secondary to the capsule associated with the artificial urethral sphincter device

Background

Urethral obstruction secondary to artificial urethral sphincter (AUS) implantation is a recognized complication in dogs. However, urethral obstruction secondary to AUS‐associated capsule formation has been described rarely.

Hypothesis

Describe clinical and diagnostic findings, management, and outcome in 6 dogs with urethral obstruction secondary to AUS‐associated capsule formation.

Animals

Six client‐owned dogs.

Methods

Retrospective study. Medical records between January 1, 2010, and June 30, 2021, were reviewed to identify dogs with urethral obstruction associated with the AUS device.

Results

The AUS device was implanted a median of 884 days (range, 20‐2457 days) before presentation for urethral obstruction. Median age at time of urethral obstruction was 4.7 years (range, 3.1‐8.7 years). Clinical signs at the time of urethral obstruction were stranguria (n = 4), pollakiuria (3), weak urine stream (2), and worsened urinary incontinence (1). In all dogs, the urethra was noted to be stenotic during urethroscopy and positive contrast cystourethrography. All dogs underwent surgery, and a fibrous capsule associated with the AUS was found to be causing urethral stenosis. Resolution of urethral obstruction occurred in all dogs after transection or removal of the capsule. Positive bacterial cultures were obtained from the capsule, AUS, or both in all dogs. Recurrence of urethral obstruction had not occurred in any dog at the time of follow‐up.

Conclusions and Clinical Importance

Urethral obstruction secondary to capsule formation is an uncommon but clinically important complication associated with use of the AUS. Continued investigation is needed to evaluate this complication more thoroughly, and its possible association with infection.

What are the likely causes of Breast Implant Associated Anaplastic Large Cell Lymphoma (BIA-ALCL)?

Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) is a CD30-positive, anaplastic lymphoma kinase-negative T-cell lymphoma. Where implant history is known, all confirmed cases to date have occurred in patients with exposure to textured implants. The etiopathogenesis of BIA-ALCL is likely to be multifactorial, with current evidence-based theories recognising the combination of chronic infection in setting of textured implants, gram-negative biofilm formation, chronic inflammation, host genetics (e.g. JAK/STAT, p53) and time in tumorigenesis. Proposed triggers for the development of malignancy are mechanical friction, silicone implant shell particulates, silicone leachables and bacteria. Of these, the bacterial hypothesis has received significant attention, supported by a plausible biological model. In this model, bacteria form an adherent biofilm in the favourable environment of the textured implant surface, producing a bacterial load that elicits a chronic inflammatory response. Bacterial antigens, primarily of gram-negative origin, may trigger innate immunity and induce T-cell proliferation with subsequent malignant transformation in genetically susceptible individuals. Future research, investigating BIA-ALCL genetic mutations and immunological modulation with Gram-negative biofilm in BIA-ALCL models is warranted to establish a unifying theory for the aetiology of BIA-ALCL.

Precision-porous polyurethane elastomers engineered for application in pro-healing vascular grafts: Synthesis, fabrication and detailed biocompatibility assessment

Unmet needs for small diameter, non-biologic vascular grafts and the less-than-ideal performance of medium diameter grafts suggest opportunities for major improvements. Biomaterials that are mechanically matched to native blood vessels, reduce the foreign body capsule (FBC) and demonstrate improved integration and healing are expected to improve graft performance. In this study, we developed biostable, crosslinked polyurethane formulations and used them to fabricate scaffolds with precision-engineered 40 μm pores. We matched the scaffold mechanical properties with those of native blood vessels by optimizing the polyurethane compositions. We hypothesized that such scaffolds promote healing and mitigate the FBC. To test our hypothesis, polyurethanes with 40 μm pores, 100 μm pores, and non-porous slabs were implanted subcutaneously in mice for 3 weeks, and then were examined histologically. Our results show that 40 μm porous scaffolds elicit the highest level of angiogenesis, cellularization, and the least severe foreign body capsule (based on a refined assessment method). This study presents the first biomaterial with tuned mechanical properties and a precision engineered porous structure optimized for healing, thus can be ideal for pro-healing vascular grafts and in situ vascular engineering. In addition, these scaffolds may have wide applications in tissue engineering, drug delivery, and implantable device.

The antigenicity of silk-based biomaterials: sources, influential factors and applications

Silk is an ancient material with essential roles in numerous biomedical applications, such as tissue regeneration and drug delivery, because of its excellent tunable mechanical properties and diverse physical structures. In addition to the necessary functionalities for biomedical applications, another critical factor for materials applied in biology is the appropriate immune interactions with the body. This review focuses on the immune responses of silk-based materials applied in biomedical applications, specifically antigenicity. The factors affecting the antigenicity of silk-based materials are complicated and are related to the composition and structural characteristics of the materials. At the same time, the composition of silk-based materials varies with its species sources, such as silkworms, spiders, honey bees, or engineered recombinant silk. Additionally, different processing methods are used to fabricate different material formats, such as films, hydrogels, scaffolds, particles, and fibers, resulting in different structural characteristics. Furthermore, the resulting body reactions are also different with different degrees of the immune response. Silk protein typically induces a mild immune response, and immunogenicity can play active roles in osteogenesis, angiogenesis, and protection from inflammation. However, there are some rare reports of severe immune responses caused by silk, which can result in an allergic response or tissue necrosis. The source of allergenicity in silk-based materials is currently under-studied and how to regulate and eliminate the overreaction of the immune system is essential for further applications. Overall, the diverse characteristics of silk-based materials mostly show beneficial bioresponses with mild immunogenicity, and the tunable properties make it applicable in immune-related biomedical applications.

Capsular Contracture in Breast Implant Surgery: Where Are We Now and Where Are We Going?

Capsular contracture is the leading complication after surgery with breast implants. A lot of progress has been made investigating this complication over the years, and knowledge has been gained on this complication. Currently, the exact cause for capsular contracture is still unclear. It has been hypothesized that immunobiological factors (i.e., immunological and bacterial factors) and several risk factors play a central role in its development. In this paper, we give an overview of the known immunological factors that have been investigated in contracted and non-contracted capsules, as well as the role of bacterial formation around breast implants. We also report on risk factors that might increase the risk of capsular development. Lastly, it provides the latest research on this matter and discusses future perspectives as follow-up research is needed to unravel the pathogenic process leading to capsular contracture. This knowledge is of interest to establish medical therapies in order to prevent such side effects. Overall, capsular contracture seems to be a multifactorial condition consisting of several risk factors. LEVEL OF EVIDENCE V: 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 .

Evaluating the Necessity of Capsulectomy in Cases of Textured Breast Implant Replacement

BACKGROUND

Capsulectomy has traditionally been recommended as a treatment for capsular contracture after breast augmentation. With the advent of breast implant-associated anaplastic large-cell lymphoma (BIA-ALCL), and the Food and Drug Administration's decision to ban Biocell textured devices, this operation has taken on new importance. This review was undertaken to better inform clinical recommendations for women with textured devices.

METHODS

An electronic search was performed using PubMed to identify all the available literature on the subject of capsulectomy and open capsulotomy (the alternative treatment).

RESULTS

Fifty-seven articles on this topic were identified. Capsulectomy was widely recommended for treatment of capsular contracture, although many authors recommended leaving thin capsular tissue behind in the absence of symptoms. En bloc resection was recommended only for women with a diagnosis of BIA-ALCL. No information supported a prophylactic role for capsulectomy in asymptomatic women with textured breast implants who are concerned regarding their future risk of BIA-ALCL. Routine pathologic examination in asymptomatic patients was not supported.

DISCUSSION

Capsulectomy adds substantially to the surgical risk, discomfort, recovery time, and expense. Implant removal or replacement without a simultaneous capsulectomy is atraumatic and poses negligible risk.

CONCLUSIONS

Capsulectomy introduces additional morbidity and is not mandatory for asymptomatic patients. Implant removal or exchange for smooth implants without a capsulectomy may be an acceptable choice for many women who do not demonstrate capsular pathology. However, any symptoms or surgical findings suggesting pathology warrant a capsulectomy. En bloc resections are reserved for patients diagnosed with BIA-ALCL.

Capsulectomy, Implant Exchange, and Placement of Acellular Dermal Matrix Is Effective in Treating Capsular Contracture in Breast Augmentation Patients

BACKGROUND

Capsular contracture is a common complication of breast augmentation surgery and many techniques to prevent and treat it have been suggested with inconsistent or variably effective results.

OBJECTIVES

The aim of this paper was to describe a protocol for treating established capsular contracture after breast augmentation with a low recurrence rate.

METHODS

From January 2009 to December 2012, 79 previous bilateral breast augmentation patients presented for treatment of established capsular contracture. There were 135 breasts with capsular contracture: 56 were bilateral and 23 were unilateral. Ten patients opted for no treatment; 2 patients opted for implant removal. Twenty-four were treated with the ICES (implant exchange, capsulectomy, and possible exchange of site) protocol and 43 were treated with the SPICES (Strattice placement in the reconstructive position, implant exchange, capsulectomy, and possible exchange of site) protocol.

RESULTS

The 24 patients treated with the ICES protocol had a recurrent capsular contracture rate of 15%. The 43 patients treated with the SPICES protocol had a 2.7% recurrent capsular contracture incidence and an 2.7% complication rate.

CONCLUSIONS

Capsular contracture after breast augmentation, whether primary or recurrent, can be successfully treated with the SPICES protocol.

LEVEL OF EVIDENCE: 4

Immediate Breast Reconstruction after mastectomy with polyurethane implants versus textured implants: A retrospective study with focus on capsular contracture

BACKGROUND

Capsular contracture (CC) is the most common complication following Immediate Breast Reconstruction (IBR) with breast implants. Different implant surfaces were developed aiming to reduce the incidence of CC. We evaluated the incidence and degree of CC after Direct-to-Implant (DTI) IBR with insertion of textured (TE) or polyurethane (PU) covered implants.

METHODS

A retrospective review of consecutive patients treated at our Institution with mastectomy and one-stage IBR and implant reconstruction between 2013 and 2018, with or without post mastectomy radiation therapy (PMRT), was conducted. Immediate breast reconstruction was performed by implanting 186 PU covered implants and 172 TE implants.

RESULTS

Three-hundred-twelve women underwent 358 DTI IBR with PU or TE implants, were analyzed with a median follow-up time of 2.3 years (range 1.0-3.0). The overall rate of CC Baker grade III and IV was 11.8% (95%CI: 8.4-16.3), while, after PU and TE implant placement it was 8.1% (95% CI: 4.1-15.7) and 15.8% (95% CI: 4.1-15.7) [p = 0.009]), respectively. Irradiated breasts developed CC more frequently rather than non-irradiated breasts (HR = 12.5, p < 0.001), and the relative risk was higher in the TE group compared with the PU group (HR = 0.3, p = 0.003).

CONCLUSIONS

After mastectomy and one-stage IBR, the use of PU covered implants is associated with a lower incidence of CC compared to TE implants. This advantage is amplified several folds for patients who necessitate PMRT. Footnote: Capsular contracture (CC); Immediate Breast Reconstruction (IBR); Directto- Implant (DTI); Textured (TE); Polyurethane (PU); Post mastectomy radiation therapy (PMRT); Nipple Sparing mastectomy (NSM).

Novel Histopathologic and Immunohistochemical Observations in Explanted Orbital Peri-implant Capsules

PURPOSE

To describe the histopathologic and immunohistochemical characteristics of peri-orbital implant capsule and correlate the observed changes with delayed implant extrusion.

MATERIALS AND METHODS

Prospective, ex-vivo, histopathologic, immunohistochemical study of peri-implant capsules excised from capsules surrounding a poly-methyl metha acrylate (PMMA) implant. Thirteen capsules were harvested and divided into two groups. Group 1 (implant extrusion group) consisted of capsules harvested from around exposed/extruded implants and Group 2 (implant non-extrusion group) from implants that were surgically exchanged for volume augmentation. Data collected included demography, clinical presentations, etiology of the explantation, age of the capsule in months, inflammatory cells noted/high power field (HPF), CD3, CD20, and CD68, percentage Masson's trichrome staining and mean capsular thickness.

RESULTS

Mean patient age at presentation was 33 ± 13 years. Of the 13 capsules included, 7 belonged to group 1and 6 to group 2. Mean age of the fibro-collagenous membranes were 33 ± 57 months (median 13 months). Median CD3, CD20, and CD68 positivity was 80%, 9%, and 7% denoting a predominant T-lymphocytic response. Mean capsular thickness was 733 ± 422µ (median 678µ). Age of the harvested capsule showed a linear correlation with inflammatory cells/HPF (r = 0.93, p < .0001, 95% C.I. 0.73 to 0.98), with CD3 positivity (r = 0.6, p = .04, 95% C.I. 0.02 to 0.9), with capillary proliferation/HPF (r = 0.85, p = .003, 95% C.I. 0.43 to 0.96) and with percentage of cells showing Masson's trichrome stain positivity (r = 0.71, p = .03, 95% C.I. 0.08 to 0.93). In the extrusion group, the capsules demonstrated high inflammation and low fibrosis.

CONCLUSIONS

PMMA orbital spherical implant incites a predominantly T-cell mediated inflammatory response which clinically presents as a peri-implant capsule. Increasing inflammation in the absence of significant fibrosis may be responsible for delayed PMMA implant exposure and extrusion.

Co-effects of C/Ag dual ion implantation on enhancing antibacterial ability and biocompatibility of silicone rubber

Although silicone implants are the most popular choice around the world for breast augmentation, reconstruction, and revision, due to the poor antibacterial properties and limited biocompatibility of silicone rubber (SR), one of the major complications, capsule contracture, is a lingering problem. To overcome the two main shortcomings, a dual ion implantation technique was applied to modify the surface of SR with the basic skeleton element of organic matter, carbon (C) and the broad-spectrum bactericide, silver (Ag). We present surface characterization, toxicological effects, and evaluation of the mechanical, antibacterial and biocompatible properties of C and Ag co-implanted SR (C/Ag-SRs). After ion implantation, surface roughness and tensile strength of these new materials increased. Biotoxicity was fully assessed by in vitro experiments on human fibroblasts and in vivo experiments on rats, showing that the low-Ag groups met safety standards. Both the anti-bacterial adhesion and bactericidal abilities of C/Ag-SRs were superior to those of SR, which had few antibacterial activities, especially against Staphylococcus epidermidis. With respect to biocompatibility, the adhesion of fibroblasts was promoted, while their proliferation was moderately inhibited on ion-implanted surfaces. After subcutaneous implantation in rats for 7, 30, 90 and 180 d, the capsular thickness around C/Ag-SRs was significantly lower than that around the SR. Additionally, there was no difference in the inflammatory reaction after 7 d of retention in vivo between C/Ag-SRs and SR. The results demonstrate that C/Ag-SRs are desirable shell materials for breast implants.

Does Implant Surface Texture Affect the Risk of Capsular Contracture in Subglandular Breast Augmentation and Breast Augmentation-Mastopexy?

BACKGROUND

Previous studies have reported decreased rates of capsular contracture associated with the use of textured surface breast implants placed in the subglandular plane during breast augmentation. However, since the publication of these studies, our understanding of the pathophysiology of capsular contracture, as well as the surgical techniques utilized to minimize bacterial contamination of the implant, have advanced considerably.

OBJECTIVES

The purpose of this study was to re-evaluate the relation between implant surface texturization and capsular contracture rates for breast implants placed in the subglandular plane during primary breast augmentation.

METHODS

Retrospective chart review was performed of all primary subglandular breast augmentation procedures involving the use of either smooth or textured round silicone gel implants, with or without simultaneous mastopexy. The primary outcome measures included clinically significant capsular contracture (Baker grade III/IV) and revision surgery for capsular contracture.

RESULTS

Between 2010 and 2017, 526 patients underwent primary subglandular breast augmentation with either smooth (n = 212) or textured (n = 314) round silicone gel implants; 248 patients underwent breast augmentation, whereas 278 underwent breast augmentation-mastopexy. Average follow-up was 756 days in the textured group and 461 days in the smooth group. Five cases of capsular contracture were observed in the textured group, and 7 cases of capsular contracture were observed in the smooth group (P = 0.20).

CONCLUSIONS

Smooth surface implants placed in the subglandular plane were not at a significantly increased risk of capsular contracture compared with textured surface implants. We suggest that adherence to a surgical technique focused on minimizing bacterial contamination of the implant is of greater clinical significance than implant surface characteristics when discussing capsular contracture.

LEVEL OF EVIDENCE: 4

Size matters-in vitro behaviour of human fibroblasts on textured silicone surfaces with different pore sizes

Capsular contracture remains a challenge in plastic surgery and represents one of the most common postoperative complications following alloplastic breast reconstruction. The impact of the surface structure of silicone implants on the foreign body reaction and the behaviour of connective tissue-producing cells has already been discussed. The aim of this study was to investigate different pore sizes of silicone surfaces and their influence on human fibroblasts in an in vitro model. Four different textures (no, fine, medium and coarse texture) produced with the salt-loss technique, have been assessed in an in vitro model. Human fibroblasts were seeded onto silicone sheets and evaluated after 1, 4 and 7 days microscopically, with viability assay and gene expression analysis. Comparing the growth behaviour and adhesion of the fibroblasts on the four different textures, a dense cell layer, good adhesion and bridge-building ability of the cells could be observed for the fine and medium texture. Cell number and viability of the cells were increasing during the time course of experiments on every texture. TGFß1 was lowest expressed on the fine and medium texture indicating a trend for decreased fibrotic activity. For silicone surfaces produced with the salt-loss technique, we were able to show an antifibrotic effect of smaller sized pores. These findings underline the hypothesis of a key role of the implant surface and the pore size and pore structure in preventing capsular contracture.

Removal of Nasal Silicone Implant and the Impact of Subsequent Capsulectomy

BACKGROUND

Little is known about contributory factors of unremoved periimplant capsule causing nasal deformities after postrhinoplasty silicone implant extraction. This study investigated the impact of retained capsule causing contracture deformity and effect of subsequent capsulectomy in preventing and correcting the deformity.

METHODS

A total of 103 patients underwent secondary surgery for silicone implant removal and grafted cartilage between May of 2015 and June of 2017. Among them, 67 patients without septal extension graft or open wound and with 8-week or more follow-up were analyzed retrospectively. All operations were approached with an intranasal incision. Three procedures were performed: (1) removal of implant plus tip graft only (n = 12), (2) removal of implant plus tip graft plus subtotal capsulectomy (n = 47), and (3) removal of implant plus tip graft plus subtotal capsulectomy in patients with contraction and thick capsule (n = 8). Preremoval/postremoval of nasal bridge length index and nasolabial angle were measured with the lateral view.

RESULTS

In group 1, nasal bridge length index decreased by 6.2 percent and nasolabial angle increased by 5.7 percent. In group 2, nasal bridge length index increased by 2.5 percent and nasolabial angle decreased by 2.2 percent. In group 3, nasal bridge length index increased by 8.6 percent and nasolabial angle decreased by 7.9 percent.

CONCLUSIONS

For patients undergoing surgical removal of a nasal silicone implant with or without cartilage, a concomitant capsulectomy is required to prevent potential contractures and to minimize tip deformity. Capsulectomy can release and lengthen the contracted nose without septal extension or derotation grafting. Dorsal skin irregularity did not occur regardless of whether capsulectomy was performed.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Recommendations for the Use of Antibiotics in Primary and Secondary Esthetic Breast Surgery

The use of systemic prophylactic antibiotics to reduce surgical-site infection in esthetic breast surgery remains controversial, although the majority of surgeons prefer to utilize antibiotics to prevent infection. Nonetheless, postoperative acute and subclinical infection and capsular fibrosis are among the most common complications following implant-based breast reconstruction. After esthetic breast augmentation, up to 2.9% of women develop infection, with an incidence rate of 1.7% for acute infections and 0.8% for late infections. After postmastectomy reconstruction (secondary reconstruction), the rates are even higher. The microorganisms seen in acute infections are Gram-positive, whereas subclinical late infections involving microorganisms are typically Gram-negative and from normal skin flora with low virulence. In primary implantation, a weight-based dosing of cefazolin is adequate, an extra duration of antibiotic cover does not provide further reduction in superficial or periprosthetic infections. Clindamycin and vancomycin are recommended alternative for patients with β-lactam allergies. The spectrum of microorganism found in late infections varies (Gram-positive and Gram-negative), and the antibiotic prophylaxis (fluoroquinolones) should be extended by vancomycin and according to the antibiogram when replacing implants and in secondary breast reconstruction, to target microorganisms associated with capsular contracture. All preoperative antibiotics should be administered <60 minutes before incision to guarantee high serum levels during surgical procedure.

PCR Characterization of Microbiota on Contracted and Non-Contracted Breast Capsules

BACKGROUND

The aetiology of capsular contracture around breast implants remains unclear. The leading theory is that a subclinical infection around the implant plays a role in the development of capsular contractions. Several studies found associations between the presence of bacteria and the occurrence of capsular contraction. However, it is unclear whether detected bacteria originate from the breast capsule, breast glandular tissue or skin contamination. Moreover, this has never been investigated with molecular techniques. The aim of this study was to assess the bacterial microbiota on breast capsules, glandular tissue and skin using a highly sensitive PCR assay.

MATERIALS AND METHODS

Fifty breast capsules were collected during implant removal or replacement. Ten specimens of glandular breast tissue and breast skin were collected in females who were undergoing reduction mammoplasty. A sample specimen (4 mm) was sterilely obtained from all tissues. All specimens were analysed by IS-pro, a 16S-23S interspace region-based PCR assay.

RESULTS

Low numbers of Staphylococcus spp. (four species in four capsules) were found on breast capsules. There was no difference in bacterial presence between normal and contracted capsules. The skin of the breast-harboured Streptococcus spp. and Staphylococcus spp. while the glandular tissue was sterile.

CONCLUSION

The low numbers of bacteria found on the capsules are most likely caused by contamination during capsule removal. More and larger studies are needed to investigate the bacterial presence on breast capsules using a PCR assay. This is the first study in which breast capsules have been studied using a highly sensitive PCR assay.

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 .

Toll-Like Receptors (TLRs) Expression in Contracted Capsules Compared to Uncontracted Capsules

INTRODUCTION

The etiology of capsular contracture after surgical implantation of breast implants remains unclear, but an important role is seen for the immune system. Toll-like receptors are immune receptors recognizing both pathogen-associated molecular patterns and damage-associated molecular patterns. The former are present on bacteria such as Staphylococcus epidermidis (bacteria earlier associated with capsular contracture), and the latter are released after (mechanical) stress. The aim of this study was to investigate the expression of TLRs 1-10 in relation to capsular contracture.

MATERIALS AND METHODS

Fifty consecutive breast capsules were collected during implant removal or replacement. The extent of capsular contracture was scored according to the Baker score. A sample specimen (0.5 cm3) was obtained from all tissues. cDNA was synthesized from isolated mRNA from the collected specimens. PCR analyses were conducted to test for cDNA presence and to quantify concentration. TLR1-10 expression was measured for each of the Baker scores separately and compared to all Baker scores.

RESULTS

Expression of all TLRs in all Baker scores was seen. TLR2 and TLR6 were more often present in contracted samples (Baker 3 or 4) compared to uncontracted samples (Baker 1 or 2) [Baker 2 vs. 3 (p = 0.034) and Baker 2 vs. 3 (p = 0.003), respectively]. None of the TLRs displayed a significantly higher expression in contracted capsules compared to uncontracted capsules.

CONCLUSION

This study shows that TLR2 and TLR6 are more often expressed in contracted capsules compared to non-contracted capsules however not in higher concentrations.

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 retrospective review of breast reconstruction outcomes comparing AlloDerm and DermaCELL

Acellular dermal matrix (ADM) has become an accepted and advantageous adjunct to alloplastic breast reconstruction. The increase in demand has led to an upsurge of dermal-based products, both human and animal derived. There are few direct ADM comparative studies, but it is unclear whether there are any differences in complication rates. Our primary objective was to determine whether there is a difference in outcomes between AlloDerm and DermACELL in immediate alloplastic breast reconstruction.

A retrospective chart review of those who underwent immediate alloplastic breast reconstruction from January to December 2016 was performed. This encompassed 64 consecutive patients (95 breasts) with tissue expander or direct-to-implant reconstruction and either AlloDerm or DermACELL ADM. Demographics, particulars of the surgery, additional treatments and complications were all recorded. Differences in seroma, haematoma and infection rates, as well as more serious complications including implant replacement, capsular contracture and failure, were all reviewed.

The groups were comparable in terms of age, BMI and relevant comorbidities. Mastectomy weight and resulting implant volume were higher in the DermACELL group, with volume reaching statistical significance (p = 0.001). With an average follow-up of 18 months, there was no difference in capsular contraction or implant replacement. However, in those who developed capsular contracture in the DermACELL group, more breasts had no history of radiation, which was significant (p = 0.042). Overall, there were no significant differences in complication rates of seroma, haematoma, mastectomy flap necrosis and infection.

Back to Basics: Could the Preoperative Skin Antiseptic Agent Help Prevent Biofilm-Related Capsular Contracture?

BACKGROUND

Capsular contracture (CC) has remained an unresolved issue throughout history. Strong evidence focuses on bacterial biofilm as its main source. A literature review revealed that more than 90% of bacteria found in capsules and implants removed from patients with Baker grade III-IV CC belong to the resident skin microbiome (Staphylococcus epidermidis, predominant microorganism). The use of an adequate preoperative skin antiseptic may be a critical step to minimize implant contamination and help prevent biofilm-related CC.

OBJECTIVES

The authors sought to compare the effect of 2 different antiseptic skin preparations: povidone-iodine (PVP-I) vs chlorhexidine gluconate (CHG) on CC proportions after primary breast augmentation through a periareolar approach.

METHODS

In June of 2014, The Society for Healthcare Epidemiology of America proposed to use CHG for preoperative skin preparation in the absence of alcohol-containing antiseptic agents as strategy to prevent surgical site infection. The clinical safety committee of a surgical center in Colombia decided to change PVP-I to CHG for surgical site preparation thereafter. The medical records of 63 patients who underwent to primary breast augmentation through a periareolar approach during 2014 were reviewed. In the first 6 months PVP-I was used in 32 patients, and later CHG was employed in 31 patients.

RESULTS

Pearson's chi-squared test to compare CC proportions between subgroups showed a statistically significant difference. The CC proportion was higher for patients who had antisepsis with PVP-I. CC was absent when CHG was employed.

CONCLUSIONS

CHG as preoperative skin antiseptic for primary breast augmentation surgery was more effective than PVP-I to help prevent biofilm-related CC.

LEVEL OF EVIDENCE: 3

Evaluation of Antibiotic-Impregnated Mesh in Preventing the Recurrence of Capsular Contracture

BACKGROUND

Capsular contracture (CC) is the most frequently reported complication following breast augmentation. A growing body of evidence implicates subclinical (biofilm) infection around breast implants as an important cause of CC; however, effective prophylactic and treatment modalities remain controversial.

OBJECTIVES

This article aims to review a single surgeon's experience using an antibiotic-impregnated mesh as a prophylactic measure against biofilm formation and recurrent CC.

METHODS

This study retrospectively reviewed 5 consecutive patients presenting with CC (Baker grades III and IV) who were managed by capsulectomy with implant replacement and simultaneous insertion of an antibiotic-impregnated mesh. Patient demographics and major complications were recorded, including CC recurrence, reoperation, and infection.

RESULTS

Complete correction of the contracture with no recurrence was achieved in all patients at a median followup of 25 months.

CONCLUSIONS

This study demonstrates a novel technique using an antibiotic mesh to reduce bacterial access to breast implants at the time of insertion. Further investigation is warranted with more clinical cases in order to recommend this technique for the management of subclinical infection and CC.

LEVEL OF EVIDENCE: 4

Silicone breast implant modification review: overcoming capsular contracture

Background

Silicone implants are biomaterials that are frequently used in the medical industry due to their physiological inertness and low toxicity. However, capsular contracture remains a concern in long-term transplantation. To date, several studies have been conducted to overcome this problem. This review summarizes and explores these trends.

Main body

First, we examined the overall foreign body response from initial inflammation to fibrosis capsule formation in detail and introduced various studies to overcome capsular contracture. Secondly, we introduced that the main research approaches are to inhibit fibrosis with anti-inflammatory drugs or antibiotics, to control the topography of the surface of silicone implants, and to administer plasma treatment. Each study examined aspects of the various mechanisms by which capsular contracture could occur, and addressed the effects of inhibiting fibrosis.

Conclusion

This review introduces various silicone surface modification methods to date and examines their limitations. This review will help identify new directions in inhibiting the fibrosis of silicone implants.

Risk factors for developing capsular contracture in women after breast implant surgery: A systematic review of the literature

BACKGROUND

Capsular contracture is the most frequent complication in breast augmentation or reconstruction with breast implants. The exact mechanism for this complication is not completely understood. Yet, it is most likely to be a multifactorial condition. Several patient-, surgery-, and implant-specific risk factors have been related to cause capsular contracture. This review aims to provide a clear overview of all risk factors for capsular contracture.

METHODS

A systematic literature review was performed focusing on patient-, surgery-, and/or implant-related factors related to capsular contracture in breast implants. PubMed, Embase, and Wiley/Cochrane Library databases were searched for relevant articles published from inception up to October 20, 2016. The included studies were assessed for the following main variables: study characteristics, patient characteristics, indication for surgery, type of surgery, implant characteristics, and other characteristics.

RESULTS

Data on the risk factors for the development of capsular contracture were retrieved from 40 studies. A presumptive increased risk in the development of capsular contracture is shown for the following variables: longer duration of follow-up, breast reconstructive surgery in patients with a history of breast cancer, subglandular implant placement, postoperative hematoma, and a textured implant surface. There is little, weak, or no evidence for the association of other factors with capsular contracture. This review also shows a large heterogeneity between studies and within the definition of capsular contracture.

CONCLUSION

This review provides an overview of the relationship between patient-, surgery-, and implant-specific risk factors in the development of capsular contracture.

Poly Implant Prothèse silicone breast implants: implant dynamics and capsular contracture

Background

The Poly Implant Prothèse (PIP) implants were withdrawn from the market in 2010 due to the use of low-grade silicone, causing a high risk for implant rupture. The aim of this study was to investigate the implant dynamics of PIP breast implants, as well as to determine the rate and predictors of implant gel bleeding, rupture, and capsular contracture in PIP implants.

Methods

Eighty women with a total of 152 PIP implants who underwent a reoperation in 2012 were enrolled in this study. Physical investigation included assessing the Baker score and demographics were retrospectively traced in medical records. The pre- and post-operative volumes of the implants were calculated and their state was determined intraoperatively by the surgeon.

Results

The implants were removed after a mean implant duration of 11 ± 2.1 years. Gel bleed and implant rupture occurred in respectively 42 and 25% of the implants. Intact implants had post-operative volume increase as well as decrease. There was a correlation between gel bleeding and more post-operative implant volume increase (P ≤ 0.05). Capsular contracture had a protective effect against post-operative implant volume increase (P ≤ 0.05), while a post-operative implant volume increase provided a protective influence in developing capsular contracture (P ≤ 0.05). Additionally, implant rupture led to a higher risk of capsular contracture (P ≤ 0.05).

Conclusions

We managed to illustrate that PIP implant shells were too permeable and that there is a correlation between gel bleeding and the increase of the post-operative implant volume. Implant rupture led to a higher risk for developing capsular contracture.

Level of evidence: Level III, risk / prognostic study.

Electronic supplementary material

The online version of this article (10.1007/s00238-018-1427-y) contains supplementary material, which is available to authorized users.

The aetiopathogenesis of capsular contracture: A systematic review of the literature

BACKGROUND

Capsular contracture is the most frequent complication after breast augmentation or reconstruction with breast implants. The immune system plays a prominent role in capsular contracture formation, albeit to an unknown extent. Bacterial contamination in situ has been hypothesized to be causative for capsular contracture. How this relates to the immunological processes involved is unknown. This article aims to provide an overview of immunological and bacterial factors involved in development of capsular contracture.

MATERIALS AND METHODS

We undertook a systematic literature review focused on immunological factors and microbiota in relation to capsular contraction around implants. This systematic review was performed in accordance with the PRISMA guidelines. PubMed, EMBASE, and the Cochrane databases were searched from inception up to October 2016. Included studies were assessed for the following variables: subject characteristics, number of capsules, primary indication for surgery, surgical procedure, follow-up or implant duration, study methods, type of antibiotics or medical therapies and outcomes related to microbiota and immunological factors.

RESULTS

Data on immunological factors and bacterial contamination were retrieved from 64 included studies. Notably the presence of macrophages and Staphylococcus epidermidis within capsules was often associated with capsular contracture.

CONCLUSION

This review provides a clear overview of the immunological factors associated with capsular contracture and provides a hypothetical immunological model for development of the disease. Furthermore, an overview of bacterial contamination and associations with capsular contracture has been provided. Follow-up research may result in clinical recommendations to prevent capsular contracture.

Open Capsulotomy: An Effective but Overlooked Treatment for Capsular Contracture after Breast Augmentation

Background:

The prevailing theory for capsular contracture after breast augmentation is a subclinical capsular infection. A capsulectomy, site change, and implant replacement are recommended. An open capsulotomy leaves the capsule in the patient. Theoretically, such a procedure would be ineffective because it does not remove the infected tissue. Recurrences occurred frequently in women treated in the 1970s when leaky silicone gel implants were in use. Open capsulotomy has not been studied in women implanted with third-generation devices.

Methods:

Seventy-five consecutive women with Baker III/IV capsular contractures after breast augmentation treated with open capsulotomies between 1996 and 2016 were retrospectively evaluated. The original implants were usually saline-filled (72.2%). Replacements were all smooth and round, and 92.6% were also saline-filled.

Results:

Seventeen women (22.7%) developed a recurrent capsular contracture. Two patients (2.7%) experienced a second recurrence. Patients with ruptured silicone gel implants (n = 13) had a significantly greater risk of recurrence (P = 0.01). There was no significant difference in recurrence rates comparing patients whose intact implants were reinserted (12.5%) with women whose intact implants were replaced (18.2%). Povidone–iodine irrigation did not affect the recurrence rate. Capsular contracture was corrected with 1 procedure in 77.3% of patients and 2 procedures in 97.3% of patients.

Conclusions:

Open capsulotomy is a safe and effective treatment that avoids the additional morbidity and cost of a capsulectomy. The findings challenge the infected biofilm theory of capsular contracture. Open capsulotomy deserves reconsideration by plastic surgeons.

Surface Modification of Polymeric Biomaterials Using Recombinant Spider Silk Proteins

The performance of biomaterials largely depends on the materials biocompatibility, which is directly related to unwanted side effects like foreign body responses and inflammation, and the potential of interaction of cells with its surface, for example, cell adhesion. In the distinct application of catheters, low or even no cell adhesion is eligible. To influence the properties of existing and commonly used biomaterials and to further increase their biocompatibility, a coating with a recombinantly produced spider silk protein as outer layer was applied on three selected catheter polymers (polyurethane, polytetrafluoroethylene, silicone) and evaluated based on cell adhesion. The tested cell types, HaCaT keratinocytes (epidermal cells), B50 neuronal cells, C2C12 myoblasts (muscle cells) and BALB/3T3 fibroblasts (connective tissue), exhibited low or no adhesion on the silk-coated materials. In combination with the lack of toxicity, the good biocompatibility, and the low body response, it could be shown that silk coatings have a high potential as a biomedical coating material, e.g., for catheters.

Effects of Medical Chitosan on Capsular Formation Following Silicone Implant Insertion in a Rabbit Model

BACKGROUND

Capsular contracture is a serious complication that occurs after breast implant surgery. This study was performed to confirm that medical chitosan (MC) affects capsule formation and elucidates a possible mechanism.

MATERIALS AND METHODS

In this study, we used 18 female adult New Zealand White rabbits. In each rabbit, two silicone implants were placed under the pectoralis muscle layer on both sides (one side was included in the experimental group and the other side was included in the control group). MC was applied around the silicone implant of the experiment group, while the control group received no treatment. The capsular thickness was calculated by Masson's trichrome stain. The expression of MMPs and TIMPs were determined by real-time PCR, Western blotting, and immunohistochemistry.

RESULTS

Compared to the control group, the capsular thickness of the MC group was significantly reduced at 4, 8, and 12 weeks after the operation (4 week: 229.3 ± 72.2 vs 76.1 ± 12.6 µm, p < 0.05; 8 week: 326.0 ± 53.8 vs 155.4 ± 61.7 µm, p < 0.0.5; 12 week: 151.2 ± 52.5 vs 60.0 ± 22.0 µm, p < 0.05). Compared to the control group, the MC group had significantly lower expressions of TIMP-1 and TIMP-2 (p < 0.05). However, compared to the control group, there was no statistically significant difference in the expressions of MMP-2 and MMP-9 in the experiment group (p > 0.05).

CONCLUSION

MC reduced the risk of developing capsular contracture around silicone implants, possibly by blocking the signaling pathway of TIMPs.

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.

Poly Implant Prothèse and Rofil Substandard Breast Implant Explantations from a Large German Single Centre from 2011 to 2014: A Comparative Study

BACKGROUND

Following a Europe-wide scandal, substandard breast implants containing silicone for industry purposes produced by Poly Implant Prothèse (PIP&Rofil) were explanted due to its potential health risks.

OBJECTIVE

We investigated whether these implants actually imposed a threat to patients' health.

METHODS

In this retrospective single-centre case-control study, we compared patients with breast augmentation receiving implant explantation (01/2011-01/2015). Data were collected retrospectively from the patients' records. Patients were split into two groups: PIP&Rofil and implants of other manufacturers.

RESULTS

A total of 307 patients with 495 breast implants met the inclusion criteria, 64 patients with 115 PIP&Rofil implants and 243 patients with 380 implants of other manufacturers. Comparison of descriptive statistics between the two groups revealed that for a variety of indicators (e.g. patient age, breast cancer, aesthetic vs. reconstructive indication, implant volume, submuscular vs. subglandular implant position) PIP implants differ from non-PIP implant patients. Raw mean comparison showed higher rupture rates for non-PIP implants, 28.42 % (PIP 23.48 %). However, when controlling for implant indwelling time, PIP implants had shown higher rupture rates. Both groups had similar rates of capsular contracture (PIP: 71.30 %, Others: 72.63 %) with different distribution of Baker Scores (Baker 2/3/4: PIP 5/8/13 and non-PIP 3/24/135).

CONCLUSION

Concerning patient symptoms, we did not find any objective reason to justify implant explantation of PIP&Rofil implants as a solely precautionary measure. As PIP&Rofil implants showed shorter retention periods until rupture and ruptured implants can cause symptoms or health problems, PIP&Rofil implants should be regularly monitored and explanted if there is evidence of rupture.

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.

Biological and synthetic mesh use in breast reconstructive surgery: a literature review

Mesh use in surgical breast reconstruction is becoming increasingly common; however, there is still no consensus on whether synthetic matrices or biological matrices produce the best outcomes. This review analyses these outcomes, namely the differences in aesthetic outcomes, cost, and the rates of the most commonly reported complications.

The results indicate that breast reconstruction with a synthetic matrix produces comparable aesthetic outcomes to a biological matrix, with lower costs and complication rates. The individual results for complication rates show that biological matrixes are associated with lower infection rates and slightly lower capsular contracture, but higher haematoma rates, and slightly higher rates of skin necrosis and explantation—although many had post-op radiotherapy.

The majority of the studies evaluated used biological matrices, and there are no randomised controlled trials directly comparing the two types of meshes; definite conclusions cannot be drawn from the available evidence. The authors suggest that a randomised controlled trial comparing these outcomes in synthetic and biological matrix use is needed.

The Relationship of Bacterial Biofilms and Capsular Contracture in Breast Implants

Capsular contracture is a common sequelae of implant-based breast augmentation. Despite its prevalence, the etiology of capsular contracture remains controversial. Numerous studies have identified microbial biofilms on various implantable materials, including breast implants. Furthermore, biofilms have been implicated in subclinical infections associated with other surgical implants. In this review, we discuss microbial biofilms as a potential etiology of capsular contracture. The review also outlines the key diagnostic modalities available to identify the possible infectious agents found in biofilm, as well as available preventative and treatment measures.

Response to the Comments of Dr. Chen on Chinese Women's Preferences and Concerns Regarding Incision Location for Breast Augmentation Surgery: A Survey of 216 Patients

In our previous article, preoperative education material regarding different incisions for breast augmentation surgery was compiled to help Chinese patients fully understand the characteristics of different incisions and make informed choices. Dr. Chen argued that some key indicators were missing in the instrument. However, the preoperative education material was compiled based on existing literature to provide patients with valid information. The items listed were proven to be directly connected to incision choices. The items unlisted were unconfirmed or not related to incision choices.

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.

A Rodent Model to Evaluate the Tissue Response to a Biological Scaffold When Adjacent to a Synthetic Material

The use of biologic scaffold materials adjacent to synthetic meshes is commonplace. A prevalent clinical example is two-staged breast reconstruction, where biologic scaffolds are used to provide support and coverage for the inferior aspect of the synthetic expander. However, limited data exist regarding either the kinetics of biologic scaffold integration or the host tissue response to the biologic scaffold materials used for this application or other applications in which such scaffold materials are used. The present study evaluated the temporal host response to a biological scaffold when placed adjacent to a synthetic material. Evaluation criteria included quantification of material contracture and characterization of the host cell response and tissue remodeling events. Results show a decreased thickness of the collagenous tissue layer at biologic scaffold/silicone interface compared to the abdominal wall/silicone interface during the 12-week experimental time course. All test materials were readily incorporated into surrounding host tissue.