Abstract
Breast augmentation with implants is the most common surgical aesthetic procedure performed in the United States. A number of advancements have occurred in recent years to improve implant composition and develop strategies for both predicting and optimising aesthetic outcomes. Nevertheless, complications and risks are still associated with breast implants. In this article, discussion focuses on the role of preoperative imaging, the recent developments in implant composition, the current data on complications, and risks associated with breast augmentation.

Breast augmentation has a number of potential complications, including implant rupture, rippling and leakage, asymmetry, capsular contracture, animation deformity, seroma and haematoma formation, implant extrusion, and infection. Additionally, case reports have raised concerns that there may be serious long-term sequelae from chronic exposure to implants. Questions have also been raised as to how breast implants may alter the risks of breastfeeding and that breast cancer screening guidelines may need to be modified.

This article aims to discuss the latest research in implant-based breast augmentation, including novel preoperative imaging techniques, developments in implant shape, and recent Food and Drug Administration (FDA) approved implants. Discussion will also focus on recent findings regarding the risks associated with implants and how breast augmentation changes the approach to screening and healthcare maintenance.

Methods

A PubMed search was used to compile the references for this article. Focus was placed on articles published from 2006 to 2013; they had to be written in English, and involve humans. The key words used in search engines are listed in Table 1.

Table 1

Preoperative assessment and three-dimensional imaging

In addition to explaining the risks of breast augmentation, the clinician must ensure that the patient has reasonable expectations of the aesthetic outcome and be able to guide the patient in selecting an appropriate implant. Linear measurements taken preoperatively help to estimate native breast size. However, two-dimensional assessment is limited in quantifying breast shape and volume.

Preoperative three-dimensional (3D) imaging is a new technique that can both accurately and reliably determine total breast volume, glandular distribution, breast projection, and symmetry5–10. Using a series of lasers to demarcate specific planes of the breast, images are compiled to generate a 3D model of breast shape, quantify breast volume, and determine spatial distribution5,7–11. Canfield offers the Vectra 3D imaging system (Canfield Imaging Inc, Fairfield, NJ), which uses six two-dimensional images to recreate a 3D model of the breasts with the ability to visually approximate breast appearance with a range of implants12. Crisalix also offers a 3D imaging system (Crisalix, Lausanne, Switzerland) and a virtual assistant that enables visualisation of augmentation options online13.

Using 3D imaging technology, studies have been able to objectively assess the conformation that implants assume after placement. Multiple studies have demonstrated that the ultimate projection volume of implants in vivo is 20–23% less than that purported by implant advertisements5,6,14,15. With this newfound understanding of how implants behave in vivo, 3D imaging has potentially created opportunities to individually customise breast shape and size with reliable accuracy8,9,15,16. Furthermore, the images generated by the 3D systems help a patient better predict how they will appear postoperatively, creating a more informed patient and potentially allowing for improved patient satisfaction. The significant limitation to 3D systems is their cost, making the financial implications of their use an important discussion point for patients.

Implant type

Filling: silicone versus saline

Of all breast implants placed in the United States during 2012, 62% contained silicone filling and 38% contained saline filling1. The preference of silicone over saline represents a shift from the early 1990s when a moratorium was placed on silicone implants because of a  suspicion of increased risk of systemic illnesses. After returning to the market in 2006, silicone implants have gained popularity over saline implants owing to a decrease in deflation, visual irregularities, and rippling or wrinkling4,17. The differences between the two implants are more prominent with smaller breasts, thin skin, or when the implant is placed in the sub-glandular as opposed to sub-muscular position17.

Silicone implants, however, are not without complications. They have a higher rate of capsular contracture than saline implants (13.2% versus 7.2%)18–20. Slow silicone leakage over time, also known as silicone bleed, has been implicated as a cause of capsular contracture. While saline implants deflate with leakage, silicone bleed does not result in volume depletion owing to the trapping of silicone in the fibrous capsule. Therefore, detection of silicone bleed is often made incidentally, making epidemiologic analysis of its occurrence difficult to ascertain18,21. By contrast, saline implants are known to leak in 1–7% of patients17. Newly FDA-approved high cohesive gel implants have both a thicker capsule and denser silicone filling, making them less likely to experience rupture or silicone bleed compared to the traditional non-cohesive implants19,20. This may lead to a lower capsular contracture rate among silicone implants.

The IDEAL IMPLANT® (Ideal Implant Incorporated, Dallas, TX), a saline implant with multiple nested shells and an internal baffle structure, was developed to optimise the advantages of both silicone and saline implants22. The multiple shells, available in a single lumen with saline and a double lumen with both gel and saline, are advertised to provide better contour to the chest wall and reduce wrinkling. Although not yet FDA-approved, investigational studies suggest lower rates of capsular contracture with the IDEAL IMPLANT®, though effects on leaking and deflation remain to be demonstrated23.