Breast Implant Rupture

Etiology

The most common causes of implant rupture are secondary to the normal aging of the implant, as all prostheses have a recommended lifespan and are prone to rupture eventually once this is exceeded. Literature and personal experience allow physicians to estimate this timeframe, which can range from 12 to 35 years.[4] All ruptures occurring within 20 years are premature in the case of modern implants. These early ruptures are related to various causes which include incompetent valves, manufacturing defects, and underfilling of the implant, which leads to folds in the implant capsule, thus provoking premature weaknesses in the wall. Trauma can also lead to implant rupture. Most blunt trauma does not cause a prosthesis rupture, with the possible exception of high-velocity, direct, blunt trauma to the breast (eg, impact on a steering wheel in a motor vehicle accident). Nonpenetrating traumas were encountered in closed capsulotomies of old silicone prostheses, but these are seen less frequently today as many of this generation of implants have been replaced, and more modern implant construction was designed to prevent this complication.[5][6][7][8]

Epidemiology

The incidence of implant rupture increases with the age of the implant. Prosthesis wall thickness does not play any determinant role in ruptures, as companies offer inflatable prostheses of varying wall thicknesses, and all have a similar rupture rate. Overfilling is rarely responsible for ruptures, though it is essential to comply with filling guidelines for any individual implant.

Pathophysiology

In saline prostheses, apart from the diminution in breast volume, few other symptoms can be identified. If exploration happens at a very early stage after deflation, the surgeon will notice a certain amount of clear fluid (saline from the implant) still present within the capsular pocket. If surgery is performed long after deflation, water in the capsular pocket will have diminished, and only the deflated implant will likely be encountered within the capsule. In the case of old silicone prostheses ruptures, silicone will be free inside the capsular pocket, and apart from the inflammatory process in the thickened capsule, some free and encapsulated silicone (granuloma) can be found in the surrounding tissue.

History and Physical

For saline prostheses, the most common sign associated with implant rupture is the evidence of volume diminution, which can be acute or gradual. There is rarely pain with a saline implant rupture outside of the infrequent post-traumatic ruptures. In silicone prostheses, some degree of chest wall pain may be present as the granulomatous inflammatory reaction takes place. A saline implant rupture is easy to detect on physical examination. It is often referred to as a deflated breast. It decreases in size over the course of a few days. If the saline implant deflates within a few days of insertion, is it suggestive of iatrogenic damage or an improperly closed valve.

For a mature implant, a recent history of trauma could be the cause of the rupture; but in the absence of this, manufacturing defects may be responsible, or late-stage implant failure may indicate the end of the lifespan of the implant. Silicone implant rupture is difficult to detect on physical examination, with a majority of cases being intracapsular; further evaluation with imaging is often required. Extracapsular silicone implant ruptures can sometimes produce a palpable mass or irregularity of the breast as inflammation and granulomatous tissue form; alternately, they may present with vague pain or tenderness symptoms or may be completely asymptomatic. Lymphoma has also been reported in association with a certain subset of breast implants, so the astute surgeon must always remember to query the patient regarding axillary or local masses and systemic symptoms that could herald lymphoma.

Pertinent questions for the suspected implant rupture are therefore:

• When was the implant placed?
• What type of implant was placed (if known)?
• Onset/duration of any symptoms
• Fevers/chills, or B-symptoms

Pertinent physical examination findings include:

• Breast shape and symmetry
• New breast masses
• Associated lymphadenopathy in the axillae or elsewhere
• The texture of the breast implant in question versus the contralateral breast implant
• Skin changes in the affected breast versus the contralateral breast
• Nipple discharge

Evaluation

A saline implant rupture often requires no radiographic evaluation. As described above, a simple clinical evaluation demonstrating volume loss is sufficient. If mammography imaging is obtained, then the implant will often demonstrate a wrinkled appearance. An intact implant will demonstrate a simple anechoic interior on ultrasound, while a rupture will demonstrate folds or wrinkles in the implant capsule. Magnetic resonance imaging (MRI) will show a saline implant following fluid signal on all sequences.[9][10][11]

An intracapsular silicone implant rupture is very difficult to see on mammography. A bulging of the implant contour can suggest an intracapsular rupture. Ultrasound lacks sufficient sensitivity to show intracapsular ruptures, as the silicone is relatively hypoechoic and produces significant artifacts on imaging. The most reliable finding is called a stepladder sign, in which multiple linear echoes are noted in the implant. MRI is the most sensitive at detecting silicone implant rupture. The demonstration of silicone on both sides of a radial fold is known as the keyhole, noose, or teardrop sign (all referring to the same finding). The finding of multiple folds of the implant shell layering upon itself is referred to as the linguine sign and is highly indicative of an intracapsular rupture. This should not be confused with the normal radial folds/creases of an implant, which are often straight, thick, short, and extend to the periphery of the shell. Computed tomography (CT) imaging will also demonstrate the characteristic linguine sign, but with an overall low sensitivity and high radiation dose is not used to evaluate implant rupture. It is often incidentally seen on CT.

Extracapsular rupture can often be seen with mammography and ultrasound, showing the extravasated silicone in the surrounding tissues or even axillary lymph nodes. The snowstorm sign is a sonographic finding of silicone gel droplets mixed with breast tissue, showing a heterogeneous echogenic appearance resulting from the dispersion of the ultrasound beam. MRI is still the modality of choice to determine the extent of the extravasation. The silicone will have a low signal on T1 and a high signal on T2 fat-suppressed images. Computed tomography is not used to evaluate extracapsular rupture because the silicone and the surrounding soft tissues demonstrate a similar radiodensity

Treatment / Management

The empty shell of a ruptured saline implant should be removed. A ruptured silicone implant, whether intracapsular or extracapsular, should be removed because of the possible interaction with surrounding tissue and possible spread to local lymph nodes. Replacement with a more modern implant, whether silicone or saline, should be offered. Asymptomatic patients may be reluctant to undergo this procedure, but the overall long-term safety should be emphasized, and the risk of malignancy discussed. If an intracapsular rupture occurs, then a capsulectomy can be performed. If all silicone has been cleaned (if the rupture was very recent, this is possible), the surgeon may not remove the fibrous capsule. If there is a doubt about silicone persistence, the surgeon should attempt to remove the entire fibrous capsule that has been infiltrated by silicone. A capsulectomy will be necessary in case of calcification. If the rupture is extracapsular, then it is possible that the patient will need several surgeries to retrieve all of the extravasated silicone gel, with a delayed replacement of the implant to restore normal breast contour.

Differential Diagnosis

The differential diagnosis for breast implant ruptures include the following:

• Damage by a surgical instrument

• Needle insertion during a biopsy

• Normal aging of implant

• Trauma caused by a car accident