The effect of a bacterial contamination on the formation of capsular contracture with polyurethane breast implants in comparison with textured silicone implants: an animal study

Foreign Body Reaction to Ion-Beam-Treated Polyurethane Implant

All artificial materials used for implantation into an organism cause a foreign body reaction. This is an obstacle for a number of medical technologies. In this work, we investigated the effect of high-energy ion bombardment on polyurethane for medical purposes and the reaction of body tissues to its insertion into the mouse organism. An analysis of the cellular response and shell thickness near the implant showed a decrease in the foreign body reaction for implants treated with high-energy ions compared to untreated implants. The decrease in the reaction is associated with the activation of the polyurethane surface due to the formation on the surface layer of condensed aromatic clusters with unbonded valences on the carbon atoms at the edges of such clusters and the covalent attachment of the organism's own proteins to the activated surface of the implant. Thus, immune cells do not identify the implant surface coated with its own proteins as a foreign body. The deactivation of free valences at the edges of aromatic structures due to the storage of the treated implant before surgery reduces surface activity and partially restores the foreign body response. For the greatest effect in eliminating a foreign body reaction, it is recommended to perform the operation immediately after treating the implant with high-energy ions, with minimal contact of the treated surface with any materials.

Major Clinical Adverse Events of Breast Implant in the Manufacturer and User Facility Device Experience Database

OBJECTIVE

Search the Manufacturer and User Facility Device Experience database to collect information on adverse events of breast implant. We analyzed the local complications and the breast implant illness (BII) of silicone breast implants, as well as saline breast implants separately, aim to provide a reference for women who want to breast augmentation.

MATERIALS AND METHODS

The Manufacturer and User Facility Device Experience database was queried for events reports related to the breast implant between July 1, 2012, and June 30, 2022. Event year and reporting year were summarized. Patient problem was collected and analyzed to distinguish between local complications and BII.

RESULTS

A total of 108,728 adverse events in the past 3 years were analyzed, silicone breast implants accounted for 62.1% and saline breast implants accounted for 37.9%. The most common local complication of women receiving silicone breast implants was "Capsular Contracture," accounting for 48.73%. However, the incidence of "capsular contracture" in women who received saline breast implants was only 17.49%. The most common BII was "fatigue/weakness" in both women receiving 2 different breast implants, 17.20% in women receiving silicone breast implants and 24.71% in women receiving saline breast implants. Of note, in all the reports, there was a wide variation in the timing of reporting as compared with the timing of the adverse event.

CONCLUSIONS

Although the adverse events of breast implant cannot completely be determined from this study, we provide a reference for women who want to get breast implants, so that they can choose breast implants more carefully. In addition, a better understanding of BII may allow them to think further about whether the benefits of breast implants outweigh the risks.

In Vivo Comparison of the Efficacy and Duration of Local Antibiotics on Smooth, Textured and Polyurethane Implant Surfaces

BACKGROUND

Capsular contracture is one of the most common complications after breast surgery involving silicone implants. The most likely cause of this condition is biofilm formation. In this study, the efficacy of local antibiotherapy against biofilm formation on implant surfaces was investigated.

METHODS

Thirty-six rats were divided into six groups. Three pockets were created on the dorsum of each rat, and 1 × 2 cm implant surface samples from smooth, polyurethane and textured implants were randomly placed into pockets. All samples were inoculated with staphylococcus epidermidis. In groups 1-2-3, inoculated samples were placed into the pockets and removed after 1, 6 and 24 h, respectively. In groups 4-5-6, inoculated samples immersed with rifamycin were placed and removed after 1, 6 and 24 h, respectively. Bacterial load was measured with plate count method.

RESULTS

Bacterial load was lower in groups 4-5-6 than in groups 1-2-3 (p < 0.05). In groups 4-5-6, bacterial load was lower for polyurethane than for textured surfaces at all time points (1, 6 and 24 h; p < 0.05). Again, in groups 4-5-6, bacterial load was lower for smooth than for textured surfaces at 24 h (p < 0.05). In groups 4-5-6, bacterial load was lower for polyurethane than for smooth surfaces at all time points, but difference was not statistically significant (1, 6 and 24 h; p < 0.05).

CONCLUSION

The results suggest that local antibiotic therapy was effective in reducing the bacterial load on all surfaces. The effectiveness of local rifamycin on the polyurethane surface was higher, and the duration of activity was longer than other surfaces.

NO LEVEL ASSIGNED

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 .

Capsular Contracture Rate in Augmentation Mammoplasty With Motiva Breast Implant Insertion: A Single-Center Experience in Korea

BACKGROUND

Capsular contracture is the most common complication following breast implant surgery, and the implant shell characteristics are important in preventing this complication.

OBJECTIVES

The aim of this study was to evaluate the capsular contracture rate for SmoothSilk Motiva implants (Establishment Labs Holdings Inc., New York, NY) in females who underwent primary and revisional breast augmentation over a 3-year period.

METHODS

A total of 1324 cases that took place from 2017 to 2020 were retrospectively analyzed, with 1027 being primary surgeries and 297 being revisional surgeries.

RESULTS

In the 1324 cases of augmentation mammoplasty with SmoothSilk Motiva implants, the overall capsular contracture rate was 1.8% (n = 24). The capsular contracture rate in the 1027 primary surgery cases was 1.07% (n = 11), and the capsular contracture rate in the 297 revisional surgery cases was significantly different at 4.39% (n = 13, P = .0001). More specifically, the capsular contracture rate in 182 revisional surgery for cases without capsular contracture was 1.12% (n = 2), and it showed no statistically significant difference from the rate in primary surgery cases (P = .965). However, the rate in 115 revisional surgery for cases with capsular contracture was 9.57% (n = 11), and it showed a statistically significant difference from the rate in primary surgery cases (P = .000) and the rate in revisional surgery for cases without capsular contracture (P = .001).

CONCLUSIONS

Augmentation mammoplasty with SmoothSilk Motiva implants demonstrated a lower rate of capsular contracture than traditional smooth or textured implants. Revisional surgery for cases without capsular contracture showed a similar rate of capsular contracture to primary surgery cases, but the rates were higher in revisional surgery for cases with capsular contracture.

LEVEL OF EVIDENCE: 4

Functionalization of breast implants by cyclodextrin in-situ polymerization: a local drug delivery system for augmentation mammaplasty

Mammaplasty is a widely performed surgical procedure worldwide, utilized for breast reconstruction, in the context of breast cancer treatment, and aesthetic purposes. To enhance post-operative outcomes and reduce risks (hematoma with required evacuation, capsular contracture, implant-associated infection and others), the controlled release of medicaments can be achieved using drug delivery systems based on cyclodextrins (CDs). In this study, our objective was to functionalize commercially available silicone breast implants with smooth and textured surfaces through in-situ polymerization of two CDs: β-CD/citric acid and 2-hydroxypropyl-β-CD/citric acid. This functionalization serves as a local drug delivery system for the controlled release of therapeutic molecules that potentially can be a preventive treatment for post-operative complications in mammaplasty interventions. Initially, we evaluated the pre-treatment of sample surfaces with O2 plasma, followed by chitosan grafting. Subsequently, in-situ polymerization using both types of CDs was performed on implants. The results demonstrated that the proposed pre-treatment significantly increased the polymerization yield. The functionalized samples were characterized using microscopic and physicochemical techniques. To evaluate the efficacy of the proposed system for controlled drug delivery in augmentation mammaplasty, three different molecules were utilized: pirfenidone (PFD) for capsular contracture prevention, Rose Bengal (RB) as anticancer agent, and KR-12 peptide (KR-12) to prevent bacterial infection. The release kinetics of PFD, RB, and KR-12 were analyzed using the Korsmeyer-Peppas and monolithic solution mathematical models to identify the respective delivery mechanisms. The antibacterial effect of KR-12 was assessed against Staphylococcus epidermidis and Pseudomonas aeruginosa, revealing that the antibacterial rate of functionalized samples loaded with KR-12 was dependent on the diffusion coefficients. Finally, due to the immunomodulatory properties of KR-12 peptide on epithelial cells, this type of cells was employed to investigate the cytotoxicity of the functionalized samples. These assays confirmed the superior properties of functionalized samples compared to unprotected implants.

Repeated Lipoteichoic Acid Injection at Low Concentration Induces Capsular Contracture by Activating Adaptive Immune Response through the IL-6/STAT3 Signaling Pathway

BACKGROUND

Capsular contracture is the most common complication of breast implantation surgery. Bacterial contamination was considered to play an important role in the occurrence of capsular contracture, and Gram-positive bacteria such as Staphylococcus epidermidis were discovered in the clinical specimens. Lipoteichoic acid (LTA) was a component of the cell wall of Gram-positive bacteria and was sufficient in the pathogenicity of the bacteria. The authors assumed that LTA could trigger the immunologic response against the implant and cause capsular contracture.

METHODS

The authors developed a rat model of capsular contracture by repeated injection of 10 μg/mL LTA. The histologic changes of the capsule tissue were measured by hematoxylin and eosin, sirius red, Masson, and immunohistochemical staining. The expression of related cytokines was measured by quantitative real-time polymerase chain reaction. The downstream pathway activation was shown by Western blot. The authors also applied tocilizumab, an interleukin (IL)-6 receptor antagonist, to verify the role of IL-6 in this pathologic process.

RESULTS

The authors discovered that repeated LTA injection, at a low concentration, could induce the thickening of capsule tissue, the deposition of collagen fiber, and the activation of myofibroblasts. The IL-6/signal transducer and activator of transcription 3 signaling pathway was activated in this process, and the inhibition of IL-6 receptor could relieve the symptoms. B cells and T-helper cells, especially T-helper type 1, could be related to this phenomenon.

CONCLUSIONS

The authors' research corroborated that subclinical infection could trigger capsular contracture, and the immune system played an important role in this process. The authors' results provided a possible research direction for the mechanism of bacterial infection-induced immune response against breast implants.

CLINICAL RELEVANCE STATEMENT

The authors' research provides a possible research direction for the mechanism of bacterial infection-induced immune response against breast implants, and a potential target for predicting the prognosis of capsular contracture.

Study of the Effect of Different Breast Implant Surfaces on Capsule Formation and Host Inflammatory Response in an Animal Model

BACKGROUND

Breast implants are biomaterials eliciting a physiological and mandatory foreign body response.

OBJECTIVES

The authors designed an animal study to investigate the impact of different implant surfaces on the formation of the periprosthetic capsule, the inflammatory response, and the cellular composition.

METHODS

The authors implanted 1 scaled-down version of breast implants by different manufactures on 70 female Sprague Dawley rats. Animals were divided into 5 groups of 14 animals. Group A received a smooth implant (Ra ≈ 0.5 µm) according to the ISO 14607-2018 classification, Group B a smooth implant (Ra ≈ 3.2 µm), Group C a smooth implant (Ra ≈ 5 µm), Group D a macrotextured implant (Ra ≈ 62 µm), and Group E a macrotextured implant (Ra ≈ 75 µm). At 60 days, all animals received a magnetic resonance imaging (MRI), and 35 animals were killed and their capsules sent for histology (capsule thickness, inflammatory infiltrate) and immunohistochemistry analysis (cellular characterization). The remaining animals repeated the MRI at 120 days and were killed following the same protocol.

RESULTS

MRI showed a thinner capsule in the smooth implants (Groups A-C) at 60 days (P < .001) but not at 120 days (P = .039), confirmed with histology both at 60 days (P = .005) and 120 days (P < .001). Smooth implants (Groups A-C) presented a mild inflammatory response at 60 days that was maintained at 120 days and a high M2-Macrophage concentration (anti-inflammatory).

CONCLUSIONS

Our study confirms that smooth implants form a thinner capsule, inferior inflammatory infiltrate, and a cellular composition that indicates a mild host inflammatory response. A new host inflammatory response classification is elaborated classifying breast implants into mild, moderate, and high.

Implantation and tracing of green fluorescent protein-expressing adipose-derived stem cells in peri-implant capsular fibrosis

BACKGROUND

Adipose-derived stem cells (ASCs) have been reported to reduce fibrosis in various tissues. In this study, we investigated the inhibitory role of ASCs on capsule formation by analyzing the histologic, cellular, and molecular changes in a mouse model of peri-implant fibrosis. We also investigated the fate and distribution of ASCs in the peri-implant capsule.

METHODS

To establish a peri-implant fibrosis model, customized silicone implants were inserted into the dorsal site of C57BL/6 wild-type mice. ASCs were harvested from the fat tissues of transgenic mice that express a green fluorescent protein (GFP-ASCs) and then injected into the peri-implant space of recipient mice. The peri-implant tissues were harvested from postoperative week 2 to 8. We measured the capsule thickness, distribution, and differentiation of GFP-ASCs, as well as the cellular and molecular changes in capsular tissue following ASC treatment.

RESULTS

Injected GFP-ASCs were distributed within the peri-implant capsule and proliferated. Administration of ASCs reduced the capsule thickness, decreased the number of myofibroblasts and macrophages in the capsule, and decreased the mRNA level of fibrogenic genes within the peri-implant tissue. Angiogenesis was enhanced due to trans-differentiation of ASCs into vascular endothelial cells, and tissue hypoxia was relieved upon ASC treatment.

CONCLUSIONS

We uncovered that implanted ASCs inhibit capsule formation around the implant by characterizing a series of biological alterations upon ASC treatment and the fate of injected ASCs. These findings highlight the value of ASCs for future clinical applications in the prevention of capsular contracture after implant-based reconstruction surgery.

Advances in surface modifications of the silicone breast implant and impact on its biocompatibility and biointegration

Silicone breast implants are commonly used for cosmetic and oncologic surgical indications owing to their inertness and being nontoxic. However, complications including capsular contracture and anaplastic large cell lymphoma have been associated with certain breast implant surfaces over time. Novel implant surfaces and modifications of existing ones can directly impact cell-surface interactions and enhance biocompatibility and integration. The extent of foreign body response induced by breast implants influence implant success and integration into the body. This review highlights recent advances in breast implant surface technologies including modifications of implant surface topography and chemistry and effects on protein adsorption, and cell adhesion. A comprehensive online literature search was performed for relevant articles using the following keywords silicone breast implants, foreign body response, cell adhesion, protein adsorption, and cell-surface interaction. Properties of silicone breast implants impacting cell-material interactions including surface roughness, wettability, and stiffness, are discussed. Recent studies highlighting both silicone implant surface activation strategies and modifications to enhance biocompatibility in order to prevent capsular contracture formation and development of anaplastic large cell lymphoma are presented. Overall, breast implant surface modifications are being extensively investigated in order to improve implant biocompatibility to cater for increased demand for both cosmetic and oncologic surgeries.

Silicon breast implants’ texture affecting bacterial biofilm formation

Introduction/Objective. The most important etiologic factors for both, capsular contracture (CC) and breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) is subclinical infection, defined as a response of an organism on presence of biofilm on the implant surface. The aim of this research was to examine the possibility of biofilm formation of four different bacteria (Staphylococcus epidermidis, Staphylococcus aureus, Pseudomonas aeruginosa, and Ralstonia picketti) on three differently textured silicone breast implants (Siltex, Mentor, pore size 70?150 ?m; MESMORsensitive, Polytech, pore size 50?900 ?m; and SilkSurface, Motiva pores 13 ?m) in vitro. Methods. Samples of silicone breast implant capsules (sized 1 ? 1 cm) were divided into three groups according to texture. After sterilization, 30 samples in every group were contaminated with 100 ?l of examined bacterial broth, followed by incubation which led to biofilm formation. For testing the capability of biofilm formation, modified technique with microtitar plates described by Stepanovic? was used. Results. All four examined bacteria (Staphylococcus epidermidis, Staphylococcus aureus, Pseudomonas aeruginosa, and Ralstonia picketti) form more biofilm on implants with pore sizes 50?900 ?m compared to implants with pore size 70?150 ?m and those with 13 ?m. Statistical significance was found in biofilm formation on implants with pores 70?150 ?m compared to implants with pores 13 ?m. The only exception was P. aeuruginosa which did not show significant difference in biofilm formation on implants 70?150 ?m and 13 ?m. Conclusion. Silicone breast implants with micro and nanotexture should be chosen in order to prevent biofilm formation and possible consequent complications.

Intraoperative Assessment of Endogenous Microbiota in the Breast

OBJECTIVE

 Breast surgery is considered a clean surgery; however, the rates of infection range between 3 and 15%. The objective of the present study was to intraoperatively investigate the presence of autochthonous microbiota in the breast.

METHODS

 Pieces of breast tissue collected from 49 patients who underwent elective breast surgery (reconstructive, diagnostic, or oncologic) were cultured. The pieces of breast tissue were approximately 1 cm in diameter and were removed from the retroareolar area, medial quadrant, and lateral quadrant. Each piece of tissue was incubated in brain heart infusion (BHI) broth for 7 days at 37°C, and in cases in which the medium became turbid due to microorganism growth, the samples were placed in Petri dishes for culturing and isolating strains and for identifying species using an automated counter.

RESULTS

 Microorganism growth was observed in the samples of 10 of the 49 patients (20.4%) and in 11 of the 218 pieces of tissue (5%). The detected species were Staphylococcus lugdunensis, Staphylococcus hominis, Staphylococcus epidermidis, Sphingomonas paucimobilis, and Aeromonas salmonicida. No patient with positive samples had clinical infection postoperatively.

CONCLUSION

 The presence of these bacteria in breast tissue in approximately 20% of the patients in this series suggests that breast surgery should be considered a potential source of contamination that may have implications for adverse reactions to breast implants and should be studied in the near future for their oncological implications in breast implant-associated large-cell lymphoma etiology.

Characterization of Inflammatory and Fibrotic Encapsulation Responses of Implanted Materials with Bacterial Infection

Medical device infections are costly, while preclinical assessment of antimicrobial properties for new materials is time intensive and imperfect at capturing the interrelated aspects of infection response and wound resolution. Herein, we developed an in vivo model for quantification of inflammatory and biocompatibility responses in the presence of a sustained implant-associated infection. The antimicrobial effectiveness of commercially available polymer materials was compared to that of thermoplastic polyurethane (TPU) materials modified with putative antimicrobial strategies as example test materials. Materials were incubated with bioluminescent Escherichia coli prior to implantation in a dorsal subcutaneous pocket in rats with an additional intraluminal bolus of bacteria. Infection kinetics were monitored with bioluminescence, and inflammatory infiltrate and fibrous capsule thickness were determined from stained histological sections. Our model resulted in a persistent infection, sensitive to antimicrobial effects, as the materials modified with a putative antimicrobial surface were able to significantly reduce the level of infection in animals at day 4 postimplantation with efficacy similar to that of commercially available antimicrobial drug-eluting polymers (positive controls). At day 30 postimplantation, the antimicrobial surface modified TPU tubing was found to promote complete elimination of intraluminal bacteria in the absence of antibiotics. Differences were also measurable in acute inflammation, as Wright-Giemsa staining demonstrated reduced inflammatory cell infiltration at day 4 postimplantation for antimicrobial TPU materials. Additionally, antimicrobial materials exhibited reduced fibrous capsule thickness coinciding with infection resolution, as compared to unmodified TPU controls. The developed model can be utilized for testing antimicrobial polymers in the context of a prolonged infection while also revealing concurrent differences in the infiltrating immune cell profiles and fibrous capsule thickness, thus improving the relevance of preclinical medical device material testing.

Histological evaluation of capsules formed by texturized silicone implants with and without polyester mesh coverage (Parietex®). A study on female rats

Purpose

To evaluate capsules formed by microtextured silicone implants with and without Parietex® mesh coverage histologically.

Methods

Sixty Wistar rats were divided in two groups (meshed and unmeshed). Each group was, then, divided into two subgroups for evaluation at 30 and 90 days. Capsules were analyzed based on hematoxylin and eosin (HE) and picrosirius staining.

Results

The number of fibroblasts, neutrophils and macrophages was similar among all subgroups. There was a higher lymphocyte reaction in the 30-day meshed group (p = 0.003). Giant cell reaction, granulation tissue and neoangiogenesis were similar among the subgroups. Synovial metaplasia was milder at 90-day in the unmeshed (p = 0.002) and meshed group (p < 0.001). Capsular thickness was significantly greater in the meshed samples (30-day p < 0.001 and 90-day p < 0.001). There was a similar amount of collagen types I and III in both groups.

Conclusions

The mesh-covered implants produced capsules similar to the microtextured ones when analyzing inflammatory variables. Synovial metaplasia was milder at 90 than at 30 days, and the capsular thickness was significantly greater in the meshed group. A similar amount of collagen types I and III was observed. Due to these characteristics, the mesh coverage did not seem to significantly affect the local inflammatory activity.

Does methylene blue increases capsular contracture in immediate breast reconstruction with silicone implant? An experimental study

Recently, most of the immediate breast reconstructions following mastectomy are being carried out with the use of silicone implants. In these patients, methylene blue is being used for the detection of sentinel lymph nodes. This experimental study was performed to determine the effect of methylene blue on capsular contracture around breast implants. Thirty-two Sprague Dawley rats were divided into 4 groups. Custom made silicone blocks were placed on the back of animals. In group 1, the incision was closed without performing any additional procedure. In group 2 (control), 0.1 mL of 0.9% normal saline was instilled into the pocket. Group 3 and 4 (study groups) received 0.1 and 0.2 mL of 1% methylene blue, respectively. On postoperative day 60, implants and capsular tissue were extracted. Capsule formation was evaluated both macroscopically and microscopically. The histological evaluation included capsule thickness, inflammation, neovascularization, and fibrosis gradients. Regarding capsule thickness, there were statistically significant differences between groups 1-3, 1-4, 2-3, and 2-4. Although there were more moderate and severe inflammation gradients in groups III and IV, there was no significant difference regarding inflammation severity between control and study groups. In respect of vascular proliferation, there was a statistically significant difference between control and study groups. Similarly, fibrosis gradients were higher in both groups 3 and 4. The study showed that the injection of methylene blue around silicone implants enhanced the formation of capsular contracture. In this case, the degree of contracture was independent of the dose given. Abbreviations: CC: capsular contracture; MM: methylene blue; SLNB: sentinel lymph node biopsy; NS: normal saline; H&E: hematoxylin and eosin; D: dorsal; V: ventral; L: lateral; n: frequency.

Study on the Effects of Estradiol in Staphylococcus epidermidis Device-Related Capsule Formation

BACKGROUND

Capsular contracture, mainly caused by Staphylococcus epidermidis (S. epidermidis) biofilm formation, is a complex problem for breast cancer patients who undergo surgical prosthetic breast reconstruction. Estradiol has been reported to be involved in the formation of bacterial biofilms. Thus, the underlying mechanism of estradiol in capsular contracture needs to be investigated.

METHODS

Biofilm-related gene expressions were measured by qRT-PCR after sterilizing the silicone with bacterial suspension and E2 treatment in vitro. Rat models were established with bilateral ovariectomy operations and estradiol subcutaneous injections. The effects of estradiol on capsular contracture were detected by monitoring serum estradiol levels, bacterial infection rate in organs, biofilm formation and capsular contracture in vivo; inflammatory factors in vivo were examined as well. Biofilm on the silicone implants was observed under a scanning electron microscope.

RESULTS

Both positive regulatory genes and negative regulatory genes were increased by the high concentration of estradiol, suggesting that estradiol can promote the formation of biofilm by not only positive but also negative regulations. High estradiol levels increased bacterial infection rate in organs, biofilm formation and capsular contracture. Further, high estradiol caused a large number of inflammatory cells to infiltrate and caused serious inflammatory reactions that aggravate the immune imbalances of the host.

CONCLUSION

High estradiol levels contribute to increasing capsular contracture caused by S. epidermidis biofilm formation.

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.

A multi-center, retrospective, preliminary observational study to assess the safety of BellaGel® after augmentation mammaplasty

Background

BellaGel® is the only cohesive silicone gel-filled breast implant from a Korean manufacturer, and it was first developed in 2005. It was approved by the CE in 2008, thus becoming the first Asian breast implant available in the EU. We conducted this study to assess the safety of BellaGel® in patients receiving augmentation mammaplasty.

Methods

We evaluated a consecutive series of 239 patients (478 breasts) who received esthetic augmentation mammaplasty using the BellaGel® (round smooth, round textured, round nanotextured, and anatomical textured types of implant) (HansBiomed Co. Ltd., Seoul, Korea) at three clinics in Korea (JW Plastic Surgery Center, BS The Body Plastic Surgery Clinic and Grace Plastic Surgery Clinic) during a period from December 1, 2015 to January 31, 2018.

Results

A total of 239 patients with a mean age of 33.1 ± 8.5 years old were followed up during a mean period of 399.58 ± 232.71 days, where there were no cases of capsular contracture in our clinical series of the patients. Other complications include one case (0.4%) of seroma, three cases (1.3%) of hematoma, and one case (0.4%) of infection. Moreover, there were no significant differences in the cumulative incidences of complications between the four types of the BellaGel® (χ2 = 2.322, df = 3, P = 0.508). Furthermore, the cumulative Kaplan-Meier survival rate was estimated at 0.979 (95% CI 0.961–0.997).

Conclusions

Our results indicate that the BellaGel® is such a safe breast implant that surgeons might consider using it for esthetic augmentation mammaplasty.

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

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.

Smooth Muscle Alpha Actin Immunoexpression (α-Sma) and CD-117 Antibody (C-Kit) in Capsules Formed by Polyurethane Foam-Coated Silicone Implants and with Textured Surface: A Study on Rats

BACKGROUND

One of the undesirable complications that might occur after breast augmentation with silicone implants is capsular contracture. In its etiology, the relations between mast cells and myofibroblasts play an important role in collagen synthesis. Mast cells are able to activate fibroblasts into myofibroblasts, through paracrine secretions, inducing collagen production. The objectives of this study were to analyze the myofibroblast concentration through the α-SMA immunomarker and evaluate the intensity of mast cell expression against the C-Kit immunomarker.

MATERIAL AND METHOD

Sixty-four Wistar rats were used, divided into two groups (polyurethane foam and textured surface) with 32 animals in each. The animals received silicone implants on the back, below the panniculus carnosus, and after the determined period, they were killed and the capsules formed around the implants were studied. The capsules were analyzed employing the immunohistochemical technique, with the α-SMA and C-Kit immunomarkers in subgroups of 30, 50, 70 and 90 days.

RESULTS

The myofibroblast concentration was higher in the polyurethane group when compared to the textured group (30 days p = 0.105; 50 days p = 0.247; 70 days p = 0.014 and 90 days p = 0.536). The intensity of mast cell expression was more pronounced in the polyurethane group when compared to the textured group (30 days p = 0.798; 50 days p = 0.537; 70 days p = 0.094 and 90 days p = 0.536).

CONCLUSIONS

Polyurethane-coated implants induced higher concentrations of myofibroblasts and higher expression of mast cells, when compared to the textured surface implants.

NO LEVEL ASSIGNED

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 .

Association Between Breast Implant-Associated Anaplastic Large Cell Lymphoma (BIA-ALCL) Risk and Polyurethane Breast Implants: Clinical Evidence and European Perspective

This article aims to present an overview on the use of polyurethane (PU) breast implants and the possible association with the risk of developing breast implant-associated anaplastic large cell lymphoma (BIA-ALCL), with a special look at the current situation in Europe. It is well known that the real cause of BIA-ALCL remains unknown. Although this is a rare disease, many interesting theories surrounding its development have been advanced; however, none of these theories has been able to demonstrate with statistical significance, as required by the criteria of evidence-based medicine, definitive clinical proof as to why BIA-ALCL develops. It is widely assumed that the implant surface plays a crucial role. Most BIA-ALCL cases are associated with macro-textured implants, but from a strictly scientific point of view, this link is not supported by any clear clinical evidence. A deeper discussion of the various implant surfaces indicates that adding further categories to the existing surface classification (smooth, micro-, and macro-textured) should be avoided. Moreover, one of the most common misunderstandings should be clarified: PU breast implants cannot be classified as macro-textured implants. The PU foam that covers breast implants provides a completely different surface, and the mechanisms of action related to tissue adhesion, as well as to fibrous capsule formation, differ substantially from those of smooth or textured implants.

Early fragmentation of polyester urethane sheet neither causes persistent oxidative stress nor alters the outcome of normal tissue healing in rat skin

Silicone breast implant is associated with complications inherent to the surgical procedure. Prosthesis coating with polyurethane, however, commonly reduces the incidence of such complications. In this paper, the authors evaluated the inflammatory histomorphometric profile and oxidative damage associated to the implant of polyester urethane sheets. Forty-eight Wistar rats were divided into Sham or polyester urethane groups (n = 8/group) and underwent a polyester urethane implant in the dorsal skinfold. Tissue samples were collected on days seven, 30, and 90 after surgery and subjected to histomorphometric analysis and biochemical tests. Results were analyzed by one-way ANOVA (p ≤ 0.05). Peri-implant tissue samples exhibited characteristic inflammatory response associated with the biomaterial, with increased vascularization on day seven and augmented levels of IL1-b and TNF-a after 30 days. Peri-implant fibrocystic population was small on day seven, but increased considerably after 90 days. A rise in the carbonyl group levels of skin samples in the polyester urethane group was observed on day seven. Findings suggest that polyester urethane sheets undergo biodegradation at an early stage after implantation, followed by increased vascularity and microencapsulation of biomaterial fragments, without persistent oxidative damage. Fiber arrangement inside the collagen matrix results in a fibrotic scar because of polyester urethane degradation.

Frontal augmentation as an adjunct to orthognathic or facial contouring surgery

Background

The dimensions and shape of the forehead determine the esthetics of the upper third of the face. Korean young people consider a broad and smooth, rounded forehead more attractive. As a result, frontal augmentation becomes more popular in patients with dentofacial deformities. Various surgical procedures and materials have been used in frontal augmentation surgery, with associated advantages and disadvantages. Silicone is a good candidate for frontal augmentation. The author presents two cases of esthetic frontal augmentation with a prefabricated silicone implant in female patients with dentofacial deformities.

Case presentation

In case 1, a 24-year-old female patient underwent frontal augmentation surgery with simultaneous maxillomandibular and zygomatic osteotomies to correct facial asymmetry. A silicone implant was fabricated preoperatively using a positive template stone mold of her forehead. In case 2, a 23-year-old female patient underwent total facial contouring surgery including frontal augmentation for improved facial esthetics. A computed tomography (CT)-guided rapid prototype (RP) model was used to make the silicone implants. The operative procedure was safe and simple, and the silicone implants were reliable for a larger degree of frontal augmentation. Six months later, both patients had recovered from the surgery and were satisfied with their frontal shape and projection.

Conclusions

Frontal augmentation with silicone implants can be an effective adjuvant strategy to improve facial esthetics in patients with a flat and narrow forehead who undergo orthognathic reconstruction or total facial contouring surgery.

Carbon Ion Implantation: A Good Method to Enhance the Biocompatibility of Silicone Rubber

BACKGROUND

Silicone rubber and silicone rubber-based materials have been used as medical tissue implants in the field of plastic surgery for many years, but there are still some reports of adverse reactions to long-term implants. Earlier studies have shown that ion implantation could enhance the biocompatibility of biomaterials. However, whether ion implantation has a good effect on silicone rubber is unknown.

METHODS

Three types of carbon ion silicone rubber were obtained by implanting three doses of carbon ions. Then, the antibacterial adhesion properties and the in vivo host responses were evaluated. The antibacterial adhesion properties were examined by plate colony counting, fluorescence staining, and scanning electron microscopic observation. The host responses were evaluated by surveying inflammation and fiber capsule formation that developed after subcutaneous implantation in Sprague-Dawley rats for 7, 30, 90, and 180 days. In addition, the possible mechanism by which ion implantation enhanced the biocompatibility of the biomaterial was investigated and discussed.

RESULTS

Carbon ion silicone rubber exhibits less bacterial adhesion, less collagen deposition, and thinner and weaker tissue capsules. Immunohistochemical staining results for CD4, tumor necrosis factor-α, α-smooth muscle actin, and elastin showed the possible mechanism enhancing the biocompatibility of silicone rubber. These data indicate that carbon ion silicone rubber exhibits good antibacterial adhesion properties and triggers thinner and weaker tissue capsules. In addition, high surface roughness and high zeta potential may be the main factors that induce the unique biocompatibility of carbon ion silicone rubber.

CONCLUSION

Ion implantation should be considered for further investigation and application, and carbon ion silicone rubber could be a better biomaterial to decrease silicone rubber-initiated complications.

Efficacy and Safety of Povidone-Iodine Irrigation in Reducing the Risk of Capsular Contracture in Aesthetic Breast Augmentation: A Systematic Review and Meta-Analysis

BACKGROUND

Capsular contracture is common and distressing after aesthetic breast augmentation. The precise cause of capsular contracture is not well established. This systematic review investigates current available evidence regarding perioperative povidone-iodine irrigation safety and efficacy in reducing capsular contracture.

METHODS

PubMed/MEDLINE, Embase, and Scopus databases were searched for publications through December of 2014. Studies with the following criteria were included: (1) primary breast augmentation with implants; (2) perioperative povidone-iodine use; and (3) documentation of capsular contracture. Our primary outcome was incidence of Baker class III/IV capsular contracture. The methodologic quality of included studies was assessed independently. Trials were meta-analyzed to obtain a pooled odds ratio describing the effect of povidone-iodine irrigation on Baker class III/IV capsular contracture.

RESULTS

Nine studies with a total of 5153 patients undergoing aesthetic breast augmentation with implants were included. Only three comparative studies achieved high methodologic quality. The meta-analysis included four studies, with 1191 patients receiving povidone-iodine irrigation and 595 patients receiving saline irrigation. The meta-analysis favored povidone-iodine irrigation for decreasing Baker class III/IV capsular contracture (2.7 percent versus 8.9 percent; OR, 0.30; 95 percent CI, 0.18 to 0.50; p < 0.00001; I = 0 percent). The reported implant rupture rates for both saline implants and silicone implants were less than 1 percent.

CONCLUSIONS

Perioperative povidone-iodine irrigation reduces Baker class III/IV capsular contracture and is not associated with implant rupture. Low methodologic quality of included studies limits recommendations for perioperative povidone-iodine irrigation as the standard of practice. Additional high-quality trials are warranted to corroborate the findings of this meta-analysis.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, II.

Histologic, Molecular, and Clinical Evaluation of Explanted Breast Prostheses, Capsules, and Acellular Dermal Matrices for Bacteria

BACKGROUND

Subclinical infections, manifest as biofilms, are considered an important cause of capsular contracture. Acellular dermal matrices (ADMs) are frequently used in revision surgery to prevent recurrent capsular contractures.

OBJECTIVE

We sought to identify an association between capsular contracture and biofilm formation on breast prostheses, capsules, and ADMs in a tissue expander/implant (TE/I) exchange clinical paradigm.

METHODS

Biopsies of the prosthesis, capsule, and ADM from patients (N = 26) undergoing TE/I exchange for permanent breast implant were evaluated for subclinical infection. Capsular contracture was quantified with Baker Grade and intramammary pressure. Biofilm formation was evaluated with specialized cultures, rtPCR, bacterial taxonomy, live:dead staining, and scanning electron microscopy (SEM). Collagen distribution, capsular histology, and ADM remodeling were quantified following fluorescent and light microscopy.

RESULTS

Prosthetic devices were implanted from 91 to 1115 days. Intramammary pressure increased with Baker Grade. Of 26 patients evaluated, one patient had a positive culture and one patient demonstrated convincing evidence of biofilm morphology on SEM. Following PCR amplification 5 samples randomly selected for 16S rRNA gene sequencing demonstrated an abundance of suborder Micrococcineae, consistent with contamination.

CONCLUSIONS

Our data suggest that bacterial biofilms likely contribute to a proportion, but not all diagnosed capsular contractures. Biofilm formation does not appear to differ significantly between ADMs or capsules. While capsular contracture remains an incompletely understood but common problem in breast implant surgery, advances in imaging, diagnostic, and molecular techniques can now provide more sophisticated insights into the pathophysiology of capsular contracture.

LEVEL OF EVIDENCE

4 Therapeutic.

Silicone Implants with Smooth Surfaces Induce Thinner but Denser Fibrotic Capsules Compared to Those with Textured Surfaces in a Rodent Model

Purpose

Capsular contracture is the most frequent long-term complication after implant-based breast reconstruction or augmentation. The aim of this study was to evaluate the impact of implant surface properties on fibrotic capsule formation in an animal model.

Materials and Methods

Twenty-four rats received 1 scaled down silicone implant each; 12 of the rats received implants with textured surfaces, and the other 12 received implants with smooth surfaces. After 60 and 120 days, rats in each group underwent 7-Tesla Magnetic Resonance Imaging (MRI) and high-resolution ultrasound (HR-US), and specimens of the capsules were acquired and used to measure capsule thickness through histology, collagen density through picro sirius red staining, and analyses of expression of pro-fibrotic and inflammatory genes (Collagen1-4, TGFb1, TGFb3, Smad3, IL4, IL10, IL13, CD68) through qRT-PCR. Furthermore, MRI data were processed to obtain capsule volume and implant surface area.

Results

On day 60, histology and HR-US showed that fibrotic capsules were significantly thicker in the textured implant group with respect to the smooth implant group (p<0.05). However, this difference did not persist on day 120 (p=0.56). Capsule thickness decreased significantly over the study period in both smooth and textured implant groups (p<0.05). Thickness measurements were substantiated by MRI analysis and volumes changed accordingly. Implant surface area did not vary between study dates, but it was different between implant types. On day 60, the density of collagen in the fibrotic capsules was significantly lower in the textured implant group with respect to the smooth group (p<0.05), but again this difference did not persist on day 120 (p=0.67). Collagen 1 and CD68 were respectively over- and under expressed in the textured implant group on day 60. Significant differences in the expression of other genes were not observed.

Conclusion

Silicone implants with textured surfaces led to temporarily thicker but less dense fibrotic capsules compared with smooth surfaces. 7-Tesla MRI and HR-US are capable for non-invasive in-vivo assessment of capsular fibrosis in an animal model and can provide unique insights into the fibrotic process by 3D reconstruction and surface area measurement.

Effect of propranolol on capsular reaction around silicone implants in guinea pigs

PURPOSE

To evaluate the effect of propranolol on capsular architecture around silicone implants by measuring the inflammation, capsular thickness, and collagen fiber density, using a guinea pig experimental model.

METHODS

Thirty six adult male guinea pigs randomly divided into two groups (n=18) were used. Each one received a silicone implant with textured-surface. The capsular tissue around implants from untreated or treated animals with the beta-adrenoceptor antagonist propranolol (10 mg/kg, dissolved in daily water) were analyzed for inflammation by histological scoring, capsular thickness by computerized histometry, and collagen fibers type I and Type III density by picrosirius polarization at different time points (7, 14 or 21 days after silicone implantation).

RESULTS

Propranolol treatment reduced inflammation and impaired capsular thickness and delayed collagen maturation around the textured implant.

CONCLUSION

Propranolol reduces the risk of developing capsular contracture around silicone implants with textured surface.