Biofilm and Breast Implant Contracture

Biofilm and the science of this is a rapidly emerging microbial concept that all medical specialties are learning more about and having to deal with. It is relatively new and the subject of intense research. Essentially you can think of this as “communities” of bacterial microbes that are locked into a polysaccharide (basically sugar) matrix, which is in fact, exactly what is in the collagen surface of an implant.

The mechanism of formation is not well known. There are two kinds of bacteria in the body; the normal circulating inhabitants as in our intestines and breast gland, or the bacteria introduced from externally, such as in infection. Either one can circulate in our body. The normal inhabitant bacteria is usually harmless and we co-exist with this and it can even be beneficial. Externally introduced bacteria can be thought of the one associated with infection, redness, pus, fever and abscess. Either one can, however, can be the culprit in biofilm. When it comes in contact with an otherwise sterile tissue, such as the collagen surrounding an implant, it can attach, become buried deep in the layers of collagen that continue to form over top of the bacteria to the point where here is when the problem comes in: now the bacteria becomes inaccessible to antibiotics. The bacteria become incased and protected in the biofilm. Bacteria in biofilm rarely cause infection as we know it with the signs and symptoms as noted above. The signs of biofilm are the loosening of a hip implant or the failure of an eyeball lens implant, or a leak around an artificial heart valve. In plastic surgery it becomes hardening around an implant; the capsular contracture we hear about.

Since the breast gland is connected to the outside world, and thus bacteria, through the nipple and ducts, we find that the most frequently identified bacteria on breast implants is Staphylococcus epidermidis. This microbe is part of the normal microflora of the skin and breast, especially inside the breast gland and ducts.  Another frequently identified bacteria is the Propionibacterium acnes which is a common species found in the skin and throughout the intestinal tract.

The process of biofilm formation takes place in three stages as diagrammed below: attachment, maturation, and dispersion. Attachment is the initial stage in which bacteria interact with the implant surface to adhere and become embedded. During the intermediate phase of maturation, the bacteria grow and multiply to reinforce the anchoring to the implant and one another. Lastly, bacterium cells detach from the biofilm to disperse throughout its environment in the stage called dispersion. Here is where they are incased in the [brown] polysaccharide layer and protected from antibiotics.

Studies are showing that there is a relationship between biofilm infections and the development of capsular contracture around breast implants. The biofilm will create a chronic inflammation. This causes the usual think collagen capsular membrane to become thick and hard with extra fibrosis and trapped bacteria ultimately leading to contracture, hardness and deformity.

The formation of a capsule around any implant is the body’s response to a foreign object and to create a protective collagen membrane. The causes of contractures are not entirely known. There may be contributing factors other than biofilm such as bleeding or hematoma. Regardless of the cause, capsular contracture results in tightening of the collagen capsule around the breast implant. This results in varying degrees of discomfort, hardening of the breast mound, and distortion of the breast’s appearance.

Capsular Contractures are classified in plastic surgery by four grades; Baker I to IV:

• Grade I: the breast is normally soft and looks natural
• Grade II: the breast is a little firm but looks normal
• Grade III: the breast is firm and looks abnormal (visible distortion)
• Grade IV: the breast is hard, painful, and looks abnormal (greater distortion)

CAPSULAR CONTRACTURE GRADE I. Before and after

CAPSULAR CONTRACTURE GRADE II. Before and after

CAPSULAR CONTRACTURE GRADE IV. Before and after

When contracture is due to biofilm and bacteria, then this cannot be reversed. Our surgical goal is prevention. Dr Romano like other doctors strongly subscribes to the 14 POINT PLAN and the steps to prevent biofilm before it starts. This is because once the bacteria have attached and matured, they are deeply embedded in the collagen and polysaccharide matrix where antibiotics either orally or intravenously are not able to penetrate.

There are around 14 proven preventive techniques used in performing breast augmentations. Ultimately, the goal is to limit any potential contact with bacteria. Surgeons often choose an inframammary incision instead of a peri-nipple areolar incision to the decrease risk of bacterial exposure. Implants placed in the subpectoral plane beneath the pectoral muscle have shown to have a lesser incidence of capsular contractures than implants placed in the subglandular region. Minimal skin contact is another key maneuver. The Keller funnel serves as an excellent delivery system to ensure that the implant is transferred from the manufacturer to the implant pocket without contacting any other surface such as skin or gloves. Use of shields over the nipples to occlude any bacteria spread, irrigation with antibiotics, oral antibiotics and other interventions are on the list.

Not all patients with Grade I or II contracture need anything and this state, although not perfectly normal and soft, is often well tolerated. These patients may be treated nonsurgically with interventions such as massage, ultrasound, medications or other things which may stop or even slightly reverse the process.

Patients that experience a Grade III or IV capsular contracture will usually desire correction and the complete surgical removal of the scar tissue capsule that surrounds the implant. This insures removal of the entire capsule and all of the encased bacteria in the biofilm. This procedure is referred to as a capsulectomy, in which the envelope that encases the implant is removed and new implants are replaced.

Current research is focused on manufacturing implants with an antimicrobial or anti-adhesion factors on the surface to reduce the risks of capsular contracture. Studies have shown that the initial attachment of bacteria is higher in textured implants and this depends on the manufacturer and degree of texture. This does not mean that biofilms only grow on textured implants. While textured implants show enhanced adhesion of bacteria, the smooth implants are also implicated, but less.

Prevention is the best solution for capsular contracture and Dr. Romano strongly subscribes and practices this.