Distribution of organosilicon polymers in augmentation mammaplasties at autopsy

The Spectrum of Non-neoplastic Changes Associated With Breast Implants: Histopathology, Imaging, and Clinical Significance

Breast implant-associated anaplastic large cell lymphoma has been recognized as a distinct entity in the World Health Organization classification of hematolymphoid neoplasms. These neoplasms are causally related to textured implants that were used worldwide until recently. Consequently, there is an increased demand for processing periprosthetic capsules, adding new challenges for surgeons, clinicians, and pathologists. In the literature, the focus has been on breast implant-associated anaplastic large cell lymphoma; however, benign complications related to the placement of breast implants occur in up to 20% to 30% of patients. Imaging studies are helpful in assessing patients with breast implants for evidence of implant rupture, changes in tissues surrounding the implants, or regional lymphadenopathy related to breast implants, but pathologic examination is often required. In this review, we couple our experience with a review of the literature to describe a range of benign lesions associated with breast implants that can be associated with different clinical presentations or pathogenesis and that may require different diagnostic approaches. We illustrate the spectrum of the most common of these benign disorders, highlighting their clinical, imaging, gross, and microscopic features. Finally, we propose a systematic approach for the diagnosis and handling of breast implant specimens in general.

The foreign body response and morphometric changes associated with mesh-style peripheral nerve cuffs

Nerve cuffs have been used to anchor and protect penetrating electrodes in peripheral nerves and have been used as non-penetrating electrodes for neural recording and nerve stimulation. The material of choice for such applications is silicone, an inert synthetic biomaterial which elicits a minimal chronic foreign body response (FBR). While histological studies of solid silicone cuffs are available, to the best of our knowledge a comparison to other cuff designs is not well documented. Here, we describe the FBR and morphological changes that accompany nerve cuff implantation in the rat sciatic nerve by comparing a metallic mesh with and without a parylene coating to one made of silicone. Two months after implantation, we observed that such implants, irrespective of the cuff type, were associated with a persistent inflammatory response consisting of activated macrophages attached to the implant surfaces, which extended into the endoneurial space of the encapsulated nerve. We also observed foreign body giant cells in the epineurial space that were more prevalent in the mesh cohorts. The mesh cuff groups showed significant changes in several morphometric parameters that were not seen in the silicon group including reductions in nerve fiber packing density and a greater reduction of large diameter fibers. High magnification microscopy also showed greater evidence of foamy macrophages in the endoneurial space of the mesh implanted cohorts. Although the precise mechanisms are unknown, the results showed that mesh style nerve cuffs show a greater inflammatory response and had greater reductions in morphometric changes in the underlying nerve compared to silicone in the absence of a penetrating injury.

STATEMENT OF SIGNIFICANCE

While traditional silicone cuffs have been in use for decades, the inflammatory and morphometric effects of these cuffs on the underlying nerve have not been deeply studied. Further, manipulation of the foreign body response to nerve cuffs by using various materials and/or designs has not been well reported. Therefore, we report the inflammatory response around nerve cuffs of various materials and designs, as well as report morphometric parameters of the underlying nerve. These data provide important information regarding the potential for quantitative morphometric changes associated with the use of nerve cuffs, and, importantly, suggests that these changes are associated with the degree of inflammation associated with the cuff.

Silicone lymphadenopathy after breast augmentation: case reports, review of the literature, and current thoughts

BACKGROUND

Silicone lymphadenopathy after implantation of silicone breast implants is a foreign body reaction due to the release or migration of silicone into the tissues surrounding the breast implant.

METHODS

For the study, 14 cases of silicone lymphadenopathy were identified from the authors' files. Four patients had been implanted before 2000 and had various types of implants. The remaining 10 patients all were implanted between 2006 and 2009, and all had Poly Implant Prothèse (PIP) implants. In addition to an analysis of the authors' own cases, a thorough bibliographic search was initiated to identify all reports of lymphadenopathy related to silicone breast implants.

RESULTS

The implant age of the four patients implanted before 2000 was 12-34 years (mean, 17.25 years). The implant age of the 10 patients implanted after 2000 was 2-6 years (mean 3.45 years). The literature search identified 29 papers with case reports of silicone lymphadenopathy published between 1978 and 2012, with a total of 175 cases. Usable data were extracted from 164 of the 175 cases. Of these patients, 159 were implanted before (and including) the year 2000 and had a mean age of 11 years at presentation or explantation, and 5 of these patients were implanted after the year 2000 and had a mean age of 4.6 years at presentation or explantation . After inclusion of the authors' own cases, the mean age of the implants at presentation or explantation was 10.56 years in a total of 178 cases. Of these patients, 163 were implanted before (and including) the year 2000 and had a mean age of 11.16 years at presentation or explantation, and 15 of these patients were implanted after the year 2000 and had a mean age of 4.06 years at presentation or explantation.

CONCLUSIONS

Current breast implant technology has minimized the release of silicone gel due to rupture or bleeding of silicone and its migration into the surrounding tissues, thus reducing the rate of silicone lymphadenopathy in the last 10 years. The PIP implant scandal highlights the fact that disregard for the implant manufacturing technologies and standards in favor of higher profits increased rupture rates and gel diffusion, leading to increased local complication rates. Silicone lymphadenopathy is a foreign body reaction that does not warrant treatment unless it is symptomatic or interferes with breast cancer detection.

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 .

Pneumonitis caused by silicone gel following breast implant rupture

INTRODUCTION

There have been reports of pneumonitis associated with subcutaneous injection of liquid silicone, and of other pulmonary conditions due to cohesive silicone gel prostheses, but we know of no previous cases of pneumonitis associated with silicone gel.

MATERIALS AND METHODS

We report the case of a patient with a cohesive silicone gel mammary prosthesis in whom silicone-induced pneumonitis was diagnosed following radiological observation of pulmonary infiltrates and tests including transbronchial biopsy, which revealed the presence of silicone in alveolar histiocytes and small blood vessels.

CONCLUSION

Following removal of the ruptured prosthesis and a course of systemic corticoids, the patient progressed favourably.

Tissue integration of polyacrylamide hydrogel: an experimental study of periurethral, perivesical, and mammary gland tissue in the pig

BACKGROUND Polyacrylamide hydrogel (PAAG) is a nondegradable water-based polymer with high viscoelasticity. The gel is used as a tissue filler, the only risk being prolonged infection with anaerobic, contaminating microorganisms if not treated early with broad-spectrum antibiotics. OBJECTIVE With silicone gel as reference, PAAG tissue integration and migration was studied in a longitudinal study of the pig. MATERIALS AND METHODS Forty-one pigs were used. PAAG and silicone gel were injected into mammary tissue, and PAAG was injected into urethral or bladder wall or the anal canal. Tissues and regional lymph nodes were examined at 1, 1(1/2), 3, 3(1/2), 6, 12, and 14 months, and other lymph nodes and organs were examined at 1, 6, 12, and 14 months. RESULTS PAAG was invaded by macrophages and giant cells that were gradually replaced by a network of fibrous tissue. Silicone gel was seen inside these cells or as large vacuoles, surrounded by a fibrous capsule. Regional lymph nodes contained PAAG only at 1 1/2 months and silicone gel at 12 months. CONCLUSION PAAG is a stable, viscoelastic bulking agent, which unlike silicone gel is slowly integrated within its host tissue via a thin fibrous network. Long-term risk of fibrosis and migration is minimal.

MOC-PS(SM) CME article: breast augmentation

LEARNING OBJECTIVES

After studying this article, the participant should be able to: 1. Evaluate patients seeking breast augmentation using key variables to assist in selection from the choices for incision, implant type and size, and plane of dissection. 2. Minimize the need for revisionary surgery to factors beyond the surgeon's control.

SUMMARY

The purpose of this article is to provide guidelines for Maintenance of Certification continuing medical education using the breast augmentation module. It may be used as an aid in the extraction of data for 10 consecutive cases of breast augmentation and, in this regard, provides a template to facilitate the collection of pertinent information. Interspersed with the Maintenance of Certification-oriented format is continuing medical education information regarding the current state of practice concerning the multiple variables in the specific procedure of breast augmentation.

The relationship of silicone breast implants and cancer at other sites

BACKGROUND

Although most attention regarding the effects of silicone breast implants on cancer risk has focused on breast cancer, there have also been concerns regarding effects on other cancers. This includes malignancies that could occur as a result of foreign-body carcinogenesis (sarcomas) or immune alterations (hematopoietic malignancies), or cancers suggested as possibly elevated on the basis of previous epidemiologic studies (cancers of the cervix, vulva, lung, and brain).

METHODS

Searches of the English language literature on the topic of silicone breast implants and cancer risk were conducted and reviewed to determine relationships that might have etiologic relevance.

RESULTS

Epidemiologic studies provide no support for an increased risk of either sarcoma or multiple myeloma among breast implant recipients, disputing clinical and laboratory findings suggesting such a link. Although a number of epidemiologic studies have demonstrated elevated risks of cervical, vulvar, and lung cancers among breast implant patients, it is likely that these excesses relate more to lifestyle characteristics (e.g., cigarette smoking, sexual behavior) than to the effects of the implants. Brain cancer excesses, suggested in one study, have not been confirmed in either an update of the mortality experience in this study or on the basis of other investigations.

CONCLUSIONS

At present, there is no convincing evidence that breast implants alter the risk of nonbreast malignancies. Breast implant patients should continue to be monitored for longer term risks and to assess whether cancer risk is influenced by various patient and implant characteristics.

[Plastic surgical body form correction. Part II: Face-lift, periorbital surgery, and breast augmentation and reduction]

The demand for a younger appearance is increasing as the average age of the population increases. Extensive anatomic studies in recent years have improved for facial and breast reconstruction the understanding of anatomic structures and the basis of the aging process. Numerous new surgical techniques have resulted. This understanding of the anatomy of aging and the diversity of surgical methods have made the attainment of naturally young facial appearance more easily possible, in which repositioning of the tissue plays a more important role than lifting. In the past, plastic surgery of the eyelids aimed primarily at hiding the aging process, not at true anatomic restoration. Modern techniques in this field aim more toward redistribution of fatty tissues and the anatomic restoration of aging structures. In this way long-term results are stabilized and secondary stigmata can be avoided. New concepts have also been established in breast surgery that allow more natural results, particularly in augmentation. Although no single method may be designated as superior, there still exists an optimal technique suited to every patient's anatomy and personal wishes.

Breast Augmentation

LEARNING OBJECTIVES

After studying this article, the participant should be able to: 1. Understand the different variables that are inherent to breast augmentation. 2. Identify certain breast shape characteristics that make one approach more advantageous than others. 3. Take into account certain patient characteristics to develop a logical surgical plan for breast augmentation.

SUMMARY

The optimal technique for breast augmentation has always been debated, and numerous variables fit the needs of the variously shaped patients in our population. The purpose of this article is to present the advantages and disadvantages of the various techniques available in breast augmentation so that, in conjunction with the patient's physical examination, a sound surgical plan can be developed for aesthetic augmentation of the breast.

Distribution of silicon/e in tissues of mice of different fibrinogen genotypes following intraperitoneal administration of emulsified poly(dimethylsiloxane) [correction of poly(dimethysiloxane)]

Following injection into the abdominal cavity of a C57BL/6 mouse, droplets of emulsified PDMS visible by light microscopy (diameter > or = 1 microm) disseminate to multiple organs of the animal. Because fibrinogen may facilitate dissemination, we compared histologically the accumulation of PDMS droplets in lymph nodes, lungs, spleen, liver, and left kidney of Fib +/+, Fib +/-, and Fib -/- mice of C57BL/6 background 35 and 75 days after intraperitoneal injection of an emulsion of the polymer. We also used ICP-AES to assess the accumulation of silicon in the lymph nodes, livers, and spleens of the animals. The emulsion droplets ranged in diameter from approximately 0.04 to approximately 80 microm. PDMS droplets visible by light microscopy were in all organs of both Fib +/+ mice and Fib +/- mice. In those animals, droplets were invariably either within or adjacent to inflammatory cells, predominantly macrophages. In contrast, PDMS droplets were visible in none of the organs of Fib -/- mice. Despite the absence of visible droplets in them, the lymph nodes, livers, and spleens of Fib -/- mice, like the corresponding organs of Fib +/+ and Fib +/- mice, contained measurable silicon after 35 and 75 days. The amount of silicon, however, was always greater in the organs of Fib +/+ and Fib +/- mice than in the organs of Fib -/- mice. We attribute the presence of silicon in organs that had no histologic evidence of droplets to diffusion of the very smallest droplets/soluble species of PDMS from the abdominal cavity. Taken together, our data and observations implicate a role for fibrinogen in the dissemination of larger PDMS droplets in vivo. We propose this role involves recognition of droplet-bound fibrinogen by macrophages and, perhaps, other inflammatory cells, and the subsequent fibrinogen-facilitated ingestion and/or extracellular movement of the droplets by those cells.

A prospective analysis of patients undergoing silicone breast implant explantation

Despite the lack of a scientifically proven link between silicone implants and disease, many women have chosen to have their implants removed out of concern for their health. Unfortunately, there are few studies in the literature that have investigated the outcome of explanations, and there are no prospective analyses of the effect explantation has on a patient's general health. The goal of this study was to use a prospective database to determine whether there were any preoperative parameters that could be used to predict which patients would be improved following removal of silicone breast implants and to provide a quantifiable measure of that improvement. A total of 38 patients with silicone breast implants underwent operative removal of their breast implants by faculty at the University of Texas Southwestern Medical Center. They were given questionnaires regarding several personal and medical parameters to be completed preoperatively, at 6 weeks postoperatively, and at 6 months postoperatively. In addition, their physicians completed preoperative and postoperative evaluations of the patient's general health status. A control group of 38 patients was established; they were matched with the experimental group with regard to age and other initial parameters. Their responses to questionnaires were then grouped according to standard subscales to evaluate physical functioning, physical role, bodily pain, general health, vitality, social functioning, emotional role, mental health, appearance evaluation, appearance orientation, illness orientation, and body area satisfaction. When compared with the control group, we found that patients who had undergone explantation showed a temporary decrease in musculoskeletal symptoms and bodily pain, as well as an increase in vitality, mental health, and body area satisfaction. Of the experimental group, those who initially indicated a higher number of musculoskeletal symptoms and a higher appearance evaluation were more likely to indicate a significant improvement in general health since explantation.

Analysis of silicon in human tissues with special reference to silicone breast implants

The increase, in the last two decades, in the application of silicones (polysiloxanes) and inorganic silicon compounds in medicine and the food industry, has exposed the human body to extensive contacts with these substances. Most silicone breast implants contain a gel consisting of a crosslinked silicone elastomer swollen by silicone oil (PDMS). Diffusion of PDMS through the silicone elastomer envelope and rupture of the envelope with release of the gel contents both occur clinically. The amount and distribution of silicone compounds in various tissues are key issues in the assessment of health problems connected with silicone implants. We have measured by GFAAS the Si content of tissues from normal and implant patients and the organic solvent extractable Si levels (assumed to be silicone), using careful control of sample collection and preparation. Whole blood levels were: implant patients mean 38.8 (SD 25.6) (microg/kg), controls mean 24.2 (SD 26.7) (microg/kg) in one study and subsequently 103.8 (SD 112.1) and 74.3 (SD 86.5) (microg/kg) in another study. Capsular tissue levels were: gel implants 25047 (SD 39313) (mg/kg of dry tissue), saline implants 20.0 (SD 27.3) (mg/kg of dry tissue) and controls 0.24 (SD 0.39) (mg/kg of dry tissue). Breast milk levels were: implant patients mean 58.7 (SD 33.8) (microg/kg), controls mean 51.1 (SD 31.0) (microg/kg); infant formula mean was 4.40 (mg/kg). Various precautions were undertaken to avoid Si contamination in this work, the most important being a) the use of a Class 100 laboratory for sample preparation and b) application of strict and elaborate washing procedure for specimen collection tools and laboratory plasticware. This data demonstrated that to properly interpret the importance of these numbers for human health, a larger study of "normal" levels of Si in human tissues should be undertaken and factors such as diet, water, race and geographical location should be considered.

Methods for detecting silicones in biological matrixes

Methods for analyzing for silicon and silicone in biological matrixes were developed. A silicone-specific technique involved microwave digestion of samples in acid solution to rapidly break down the biological matrix while hydrolyzing silicones to monomeric species. The resulting monomeric silanol species were then capped with trimethylsilyl groups, extracted into hexamethyldisiloxane, and analyzed by gas chromatography. In serum, positive identification of silicone species with detection limits below 0.5 microgram of Si/mL are possible with this technique. The technique is compared with a silicone-specific technique, 29Si NMR, and a non-silicone-specific technique, ICP-AES. 29Si NMR was far less sensitive, with a detection limit of only 64 micrograms of Si/mL in serum when analyzing for one compound with a single sharp resonance. Inductively coupled plasma-atomic emission spectroscopy (ICP-AES) has potentially lower detection limits, but the technique is not silicone-specific and suffers from species-dependent responses.

Aesthetic management of the breast following explantation: evaluation and mastopexy options

This retrospective study reviews 720 patients referred for evaluation of their silicone gel-filled breast implants from December of 1992 to January of 1996. Of the 720 patients evaluated, 282 (39.2 percent) subsequently underwent explantation, and 59 of these patients (20.9 percent) had a breast contouring procedure performed at the time of explantation. Our definition of explantation is the operative removal of the implant as well as the implant capsule. The overall complication rate for explantation was 5 out of 282 patients (1.8 percent), whereas the rate of complication among the patients who underwent simultaneous breast contouring was 2 out of 59 patients (3.4 percent). This article presents the management of the breast following explantation, implant removal, and capsulectomy. We review both the preoperative assessment of patients seeking explantation and our technique of explantation. Additionally, we address the importance of preoperative breast ptosis in technique selection and have developed a practical clinical algorithm for guiding simultaneous explantation and breast contouring. We also identify those patients who should undergo delayed breast contouring due to associated risk factors (smoking, need for > 4 cm of nipple movement, and paucity of breast parenchyma).