Sonographic Assessment of Breast Implants Using Strain Elastography and Shear Wave Elastography in an Animal Model

BACKGROUND/AIM

To date, magnetic resonance imaging (MRI) remains the gold standard for diagnosing breast implant rupture. As MRI is an expensive procedure with limited availability, the improvement of sonographic assessment is desirable. A potentially useful tool in this regard is elastography. To evaluate the diagnostic benefits of strain elastography and shear wave elastography under standardized conditions we developed an animal model.

MATERIALS AND METHODS

An animal model was created by preparing an implant site in a chicken breast, imitating tissue layers covering a breast implant after mastectomy. Different broken and intact implants were inserted. Thereby, measurements were performed using strain elastography and shear wave elastography. For strain elastography, the resulting images were investigated on repeated patterns. The data generated by shear wave elastography were analyzed for significant differences between the ruptured and intact implants.

RESULTS

The animal model using chicken breast generated realistic images and measurements comparable to those of a human breast. Hence, ruptured and intact implants could be compared under standardized conditions. Statistical analysis showed no significant difference between intact and ruptured implants with respect to the data generated by shear wave elastography. Qualitative analysis using strain wave elastography showed different patterns between intact and ruptured implants in the animal model. Intact implants showed a characteristic sonographic image of three layers in certain levels.

CONCLUSION

Shear wave elastography does not seem to produce reliable data for the evaluation of breast implants, whereas qualitative analysis using strain elastography might be a useful tool to improve diagnostic accuracy.

ACR Appropriateness Criteria® Breast Implant Evaluation: 2023 Update

This document discusses the appropriate initial imaging in both asymptomatic and symptomatic patients with breast implants. For asymptomatic patients with saline implants, no imaging is recommended. If concern for rupture exists, ultrasound is usually appropriate though saline rupture is often clinically evident. The FDA recently recommended patients have an initial ultrasound or MRI examination 5 to 6 years after initial silicone implant surgery and then every 2 to 3 years thereafter. In a patient with unexplained axillary adenopathy with current or prior silicone breast implants, ultrasound and/or mammography are usually appropriate, depending on age. In a patient with concern for silicone implant rupture, ultrasound or MRI without contrast is usually appropriate. In the setting of a patient with breast implants and possible implant-associated anaplastic large cell lymphoma, ultrasound is usually appropriate as the initial imaging. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Imaging Features Following Breast Explant Surgery: A Pictorial Essay

Breast implants can be removed with breast explantation surgery (BES) for various reasons, including patient dissatisfaction, capsular contracture, implant infection or rupture, breast implant-associated anaplastic large cell lymphoma, and a recently emerging phenomenon called breast implant illness. There is very limited data on the imaging appearance after BES. A retrospective chart review was performed for patients with BES findings on imaging reports for the period between October 2016 and October 2021. When assessing BES techniques, a key element is determining whether the implant's fibrous capsule requires removal. The second important question is if the patient requires an additional aesthetic procedure after BES. BES techniques include capsulotomy, and partial, total, or en bloc capsulectomy. Adjunctive aesthetic or reconstructive procedures after BES include fat grafting, mastopexy, augmentation, and reconstruction with flaps. The majority of post-BES breast imaging findings are related to the surgical scar/bed, thereby confirming that the type of explantation surgery is important. Imaging findings after BES include focal and global asymmetries, architectural distortions, calcifications, calcified and non-calcified fat necrosis, masses, hematomas, seromas, capsular calcifications, and silicone granulomas. Most importantly, since these patients have residual breast tissue, paying attention to imaging features that are suspicious for breast cancer is necessary.

Assessment, Complications, and Surveillance of Breast Implants: Making Sense of 2022 FDA Breast Implant Guidance

As more information about the potential risks and complications related to breast implants has become available, the United States Food and Drug Administration (FDA) has responded by implementing changes to improve patient education, recalling certain devices and updating the recommendations for screening for silicone implant rupture. In addition to staying up-to-date with FDA actions and guidance, radiologists need to maintain awareness about the types of implants they may see, breast reconstruction techniques including the use of acellular dermal matrix, and the multimodality imaging of implants and their complications. Radiologists should also be familiar with some key differences between the updated FDA guidelines for implant screening and the imaging recommendations from the American College of Radiology Appropriateness Criteria. The addition of US as an acceptable screening exam for silicone implant rupture by the FDA is one of the most notable changes that has potentially significant implications.

Recurrent 8-Year Ongoing Unilateral Breast Seroma Formation after PIP Implant Removal-A Case Report and Review of the Literature

Late seroma formation is a rare complication after implant-based breast enlargement surgery and even less frequent after implant removal. This case report presents a case of painful recurrent seroma formation after the removal of a ruptured Poly Implants Prothèse implant.

A 52-year-old patient presented herself in our clinic with a clinical history of recurrent unilateral seroma of the right breast over a period of 8 years after the initial unilateral implant removal. Removal of the remaining implant and complete bilateral capsulectomy was performed. Intraoperative findings revealed a macroscopically thickened capsule with signs of chronic inflammation on the affected side. The clinical history and the macroscopic appearance of the capsule demanded histopathological exclusion of a possible anaplastic large cell lymphoma.

Histopathological and microbiological analysis of the capsule and encapsulated material revealed no signs of malignancy or infection. Immediate soft tissue reconstruction of the breast was successfully performed using autologous fat transfer. An aesthetically satisfying result regarding symmetry and volume was achieved, and no further seroma formation was observed within a 6-month follow-up period.

Level of evidence:  V, Case Report.

Imaging of common breast implants and implant-related complications: A pictorial essay

The number of women undergoing breast implant procedures is increasing exponentially. It is, therefore, imperative for a radiologist to be familiar with the normal and abnormal imaging appearances of common breast implants. Diagnostic imaging studies such as mammography, ultrasonography, and magnetic resonance imaging are used to evaluate implant integrity, detect abnormalities of the implant and its surrounding capsule, and detect breast conditions unrelated to implants. Magnetic resonance imaging of silicone breast implants, with its high sensitivity and specificity for detecting implant rupture, is the most reliable modality to asses implant integrity. Whichever imaging modality is used, the overall aim of imaging breast implants is to provide the pertinent information about implant integrity, detect implant failures, and to detect breast conditions unrelated to the implants, such as cancer.

Poly Implant Prothèse (PIP) incidence of rupture: a retrospective MR analysis in 64 patients

AIM OF THE STUDY

The purpose of this retrospective study was to describe the magnetic resonance imaging (MRI) features of Poly Implant Prothèse (PIP) hydrogel implants in a group of 64 patients and to assess the incidence of rupture, compared to other clinical trials.

MATERIAL AND METHODS

In this double-center study, we retrospectively reviewed the data sets of 64 consecutive patients (mean age, 43±9 years, age range, 27-65 years), who underwent breast MRI examinations, between January 2008 and October 2013, with suspected implant rupture on the basis of clinical assessment or after conventional imaging examination (either mammography or ultrasound). All patients had undergone breast operation with bilateral textured cohesive gel PIP implant insertion for aesthetic reasons. The mean time after operation was 8 years (range, 6-14 years). No patients reported history of direct trauma to their implants.

RESULTS

At the time of clinical examination, 41 patients were asymptomatic, 16 complained of breast tenderness and 7 had clinical evidence of rupture. Normal findings were observed in 15 patients. In 26 patients there were signs of mild collapse, with associated not significant peri-capsular fluid collections and no evidence of implant rupture; in 23 patients there was suggestion of implant rupture, according to breast MRI leading to an indication for surgery. In particular, 14 patients showed intra-capsular rupture, with associated evidence of the linguine sign in all cases; the keyhole sign and the droplet signs were observed in 6 cases. In 9 patients there was evidence of extra-capsular rupture, with presence of axillary collections (siliconomas) in 7 cases and peri-prosthetic and mediastinal cavity siliconomas, in 5 cases.

CONCLUSIONS

The results of this double center retrospective study, confirm the higher incidence (36%) of prosthesis rupture observed with the PIP implants, compared to other breast implants.