Breast Implants

The number of women with breast implants ranges between 1.5 and 2 million. The modern silicone implant has been available since 1963 and has undergone a multitude of subsequent mechanical and material improvements. All implants consist of a silicone elastomer shell that may be single or double lumen, with a smooth or textured surface. Contents of single chamber implants consist of either silicone gel, which is factory sealed and nonadjustable, or saline, which may be adjusted intra- and/or perioperatively. Dual chamber implants were devised to provide the benefits and camouflage of silicone texture (outer lumen), along with postoperative saline adjustability (inner lumen). Various natural oils, triglycerides, and water soluble hydrogels are currently under investigation but are not currently available in the United States.

Silicone is ubiquitous in our environment. Individual exposure occurs through contact with needles, syringes, medications (insulin, simethicone), lipstick, creams, cosmetics, and implantable devices, such as pacemakers, joint replacements, defibrillators, shunts, stents, and implants.29 Extensive research undertaken since the FDA-directed silicone breast implant moratorium in 1992 has confirmed that implantable medical grade silicone is among the least bioreactive, most inert substances available for implantation.30-32 Studies have failed to show linkage between connective tissue disease and silicone gel implants. The silicone elastomer shell and gel of breast implants, however, like all implanted devices, will trigger a foreign body inflammatory cell response, with giant cell formation and eventual scarring. The extent and impact of this fibrotic capsular response upon the fluid, and physical characteristics of breast implants is dependent upon capsular density, implant-tissue incorporation, the presence of myofibroblasts, and/or the presence of intracapsular silicone or sepsis.

Capsular contracture represents the most common complication of breast implants. It consists of progressive fibrous constriction around breast implants and is unpredictable and variable. It is graded according to a scale developed by Baker (Table 11-2) and ranges from visually imperceptible (class I), to stone hard and painful (class IV). It may occur immediately or years after implantation. There is a greater incidence associated with smooth silicone implants and with subglandular placement in cosmetic augmentation. Some theories suggest local contamination with Staphylococcus epidermidis as one inciting cause. The powder from gloves and inflammation from even limited hematomas may play a role in some cases.

Capsular contracture may cause implant deformation, migration, and rupture (Figure 11-2) and may, on occasion, become calcified and detour from effective mammography. Individual perception is dependent upon severity and on the esthetic standard of the patient. Capsular contracture is not in itself a health risk. Twenty to 50 percent of reconstruction patients who develop contractures require operative intervention.

Contractures, historically, were released through aggressive manual compression. The goal was to "pop" the surrounding constricting capsule, leading to a softer breast. This technique of closed capsulotomy resulted in occasional implant rupture, extracapsular silicone extravasation, and surgeon injury (gamekeeper's thumb). In addition to long-term failure, the technique could potentiate liability risk if future rupture was detected. Contractures today are more commonly corrected through a limited, outpatient, open capsulotomy, whereby

Table 11-2. BAKER'S CLASSIFICATION OF CAPSULE CONTRACTURE

Class I Augmented breast feels as soft as an unoperated-upon breast Class II Minimal; less soft, the implant can be palpated but is not visible Class III Moderate; more firm, the implant can be easily palpated and is visible Class IV Severe; the breast is hard, tender, painful, cold, and distorted

Reproduced with permission from Little G, Baker JL. Results of closed compression capsulotomy for treatment of contracted breast implant capsules. Plast Reconstr Surg 1980;65:30.

the fibrous capsule is surgically released and or excised (capsulectomy) (Figure 11-3).

Silicone gel is composed of an amorphous matrix consisting of silicone oils of various sizes and weights. Smaller caliber oils are known to diffuse through the elastomer shell (silicone gel "bleed") and become incorporated into the fibrous capsule. Microscopic amounts may percolate through lymphatic channels following macrophage ingestion and migrate to the regional lymph nodes. As with exposure to other medial grade silicones, there is no evidence to suggest that the minute quantities transgressing the elastomer shell have any metabolic or long-term impact.

Silicone gel implant rupture occurs in up to 63 percent of patients after 12 years, documented during surgery in patients having their implants removed.33-36 Among asymptomatic patients, the incidence of implant rupture is unknown but is believed to be significant.

Breast Implants And Breast Cancer
Figure 11-2. Left breast class III capsule contracture.
Capsular Contracture
Figure 11-3. Excised implant and enveloping capsule contracture.

Gradual attenuation of the elastomer shell, with imperceptable rupture, is well documented. Abrupt or premature rupture may be prompted by capsular contracture, implant shell infolding leading to accelerated stress fractures, and trauma. Once a gel implant shell ruptures, from longevity or trauma, the contents are usually contained within the surrounding fibrous capsule. This is likely to remain undetected and has demonstrated no systemic effects.

Post-traumatic change in the form of herni-ation, deflation, malposition, or deformation may manifest extracapsular extravasation. When this occurs, free gel may infiltrate breast parenchyma and tissue planes, and/or elicit a granulomatous foreign body reaction. This may lead to regional silicone migration, sili-cone mastitis, and formation of irregular nodules that may, on physical examination and mammography, simulate a malignancy.37 Suspected implant rupture warrants evaluation. Magnetic resonance imaging has a greater sensitivity than do either mammography or ultrasound and is the test of choice for detecting implant rupture.38 Early removal of the free sil-icone and implant, with or without implant replacement, will help to avoid these sequellae and minimize subsequent confusion in mam-mographic screening.

Silicone and saline implants are radio-opaque on mammography and have led to concerns regarding potential delay in breast cancer detection.39-40 Implant characteristics, which may affect the sensitivity of standard mammo-graphy, include implant size, the proportion of overlying breast tissue, implant placement (subglandular versus submuscular) and the presence and immobility of capsular contracture.41-42 As recommended by the American Cancer Society and the American Society of Plastic and Reconstructive Surgeons, women with breast implants should maintain the same schedule of mammography as all other women. They should secure a certified facility that has sufficient experience with breast implants and confirm the availability of displacement mam-mography (Eklund) and ultrasound. Patients with postmastectomy implant reconstruction are typically followed by physical examination only. One major epidemiologic study has confirmed that the stage at breast cancer detection in women with implants is identical or better than it is in the general population;43 a second major study from the National Cancer Institute will be addressing this question as well. In addition, there is no evidence that silicone is carcinogenic in humans. In fact, in two large studies women with implants exhibit 10 to 30 percent less breast cancer than would be statistically expected when matched with the general population; the results, however, did not show statistical significance.44-47 This issue needs further study with larger numbers of patients. The most recent large study, sponsored by the NCI (in press), shows an incidence no different than for the matched control group.

In 1992, a series of poorly documented case reports and the subsequent intense media scrutiny, combined with a temporary suspension of silicone gel implant usage by the FDA, led to lawsuits and an eventual multibillion dollar settlement with the major implant manufacturers. Only one implant company (Mentor) was allowed to provide gel implants for reconstruction patients, with specific and rigid crite ria on a highly monitored, investigational basis. There were a plethora of syndromes, autoimmune diseases, and symptoms associated with silicone breast implants, and intense litigation followed. Many of these proposed associations, such as rheumatoid arthritis, were, in fact, shown in subsequent, large retrospective studies to occur in a lesser percentage of augmented patients than in the general population. Sclero-derma-like syndromes were not shown to be associated with breast implants. The American College of Rheumatology issued on October 22, 1995, the following statement, based on accumulated data: "Studies provide compelling evidence that silicone implants expose patients to no demonstrable additional risk for connective tissue or rheumatologic disease." None of the postulated syndromes have withstood the scrutiny of prospective epidemiologic testing.48-50 Results from a large National Cancer Institute study are still pending.

The FDA has recently submitted its requirements for submission of a "premarket approval" which will, once again, enable marketing of gel implants. The protocol requires patient monitoring during an 18-month follow-up, and submission of a limited questionnaire.

Arthritis Relief Now

Arthritis Relief Now

When you hear the word arthritis, images of painful hands and joints comes into play. Few people fully understand arthritis and this guide is dedicated to anyone suffering with this chronic condition and wants relief now.

Get My Free Ebook


Responses

  • Demi Morrison
    Is there a connection between silicon breast implants and osteo arthritis?
    3 months ago

Post a comment