Breast Implants-a pictorial review of typical and atypical complications.

Transcription

1 Breast Implants-a pictorial review of typical and atypical complications. Poster No.: C-0898 Congress: ECR 2012 Type: Educational Exhibit Authors: N. B. Ibrahim, C. Kim; Burlington, MA/US Keywords: Ultrasound, MR, Mammography, Breast, Complications, Biological effects DOI: /ecr2012/C-0898 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. Page 1 of 37

2 Learning objectives 1. To illustrate the radiologic appearance of typical and atypical complications from breast implantation in multiple modalities including mammography, ultrasound and breast MRI. 2. To identify the preferred modality for work up of suspected implant complications. Background Breast implants have steadily become increasingly common worldwide as the most common type of breast augmentation. Breast implantation is utilized for both for cosmetic and reconstructive purposes. According to the American Society of Plastic Surgeons, the total number of implants worldwide is estimated to be between 5-10 million (1). Radiologists will inevitably encounter women with implants in both screening and diagnostic settings. Recognition of the radiologic appearance of both typical and atypical complications from breast implantation in numerous modalities is important to ensure prompt diagnosis and subsequent treatment. The types and incidence of complications do vary with regards to the underlying indication for implantation. Women who have undergone breast reconstruction have been noted to have earlier incidences of breast implant failure compared to women who have undergone breast augmentation for cosmetic purposes (2). Approximately half of the implants used in the United States today are saline implants with the other half are composed of silicone (1). The actual composition of the implants can vary widely, however are typically composed of an envelope or shell which holds the filler material. Additional variations exist with the presence of additional lumens which can be filled with saline or silicone (double lumen, or reverse double lumen). Given that implants are foreign bodies, the body naturally has a foreign body reaction forming a fibrous capsule. Identifying these two components can be integral to further delineate specific implant complications. Although many patients are not fully aware of their specific type of implant, knowledge of the different types of implants available is useful to correctly identify implant complications. Although women may experience a vast array of different implant complications, four main types of complications exist. Capsular contraction, implant rupture, fat necrosis, and infection. Rare entities such as Anaplastic Large Cell Lymphoma have also been recently described. The U.S. Food and Drug Administration issued a bulletin of preliminary findings and analysis in January 2011 which noted an association with the occurrence Page 2 of 37

3 of ALCL in women with both saline and silicone implants although the risk appears exceedingly low overall. Imaging findings OR Procedure details Capsular contraction The most common implant complication has been cited as capsular contraction (4-5). Silicone implants are more prone to capsular contraction given the marked foreign body reaction. The fibrous capsule contracts which then results in deformity and hardening of the implant. Patients often present with breast asymmetry with bulging, and pain. The diagnosis is usually made clinically. Breast implant rupture Although there has not been clear identifiable medical risk of presence of ruptured implants, rupture is the most common reason for removal (4). The age of the implant as well as the thickness of the envelope have been noted to correlate with incidence of implant rupture (2). Identification of saline implant rupture is usually a clinical diagnosis as the affected breast would be smaller on physical exam. Given the two main components of silicone implants-the inner envelope and outer thick fibrous capsule, two different entities of silicone implant rupture are possible. Intracapsular rupture which is the most common, refers to disruption of the inner envelope containing silicone, however the silicone material is still within the confines of the external fibrous capsule. Rupture of silicone through the thick fibrous capsule is also possible which is noted as extracapsular rupture. Free silicone is then noted to be adjacent to the fibrous capsule. Free silicone is eventually noted to be cleared by the lymphatic system and can be noted within lymph nodes (4). Mammography, ultrasound and MRI have all been used as modalities to evaluate implant rupture. Given the density of silicone, distinguishing intracapsular rupture on mammography is not possible as the internal envelope is not discernable. Both rupture of saline implants as well as extracapsular silicone rupture can be visualized by mammography. The mammographic appearance of saline implants is noted to appear as a collapsed envelope. ( Fig. 1 on page 15) Extracapsular silicone rupture is noted to appear as dense material outside of the implant on mammograms. (Fig. 2 on page 17). Dense lymph nodes may also be seen indicative of extracapsular rupture (4). Page 3 of 37

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5 Fig. 1: Left LMLO mammogram demonstrates collapsed saline implant. References: N. B. Ibrahim; Diagnostic Radiology, Lahey Clinic, Burlington, UNITED STATES OF AMERICA Ultrasound is an additional modality which offers advantage given its relative availability and low cost. Both saline and silicone implants appear as triangle shaped anechoic structures with reverberation bands anteriorly (7). If calcification of the fibrous capsule is present posterior shadowing maybe observed. Saline rupture can be noted as collapse of the saline shell. Silicone extracapsular rupture can be identified as marked echogenicity of the internal structure of the implant with scattered and reverberating echoes. This appearance has been termed the "snowstorm" appearance. (4-5, 7-8). Silicone within lymph nodes can be noted as echogenic lymph nodes with dirty shadowing. Intracapsular rupture can sometimes be identified by the "stepladder" sign which demonstrates parallel adjacent but clearly separate from the fibrous capsule (4,8). This appearance can be similar to radial folds which can be easily confused for one another. MRI examination is noted be the most sensitive and specific for evaluation of rupture (4). Generally, silicone gel demonstrates T1 low signal and T2 high signal. Silicone suppressed and silicone selective sequences are thus helpful for evaluation of implant rupture. Intracapsular rupture is typically described as the presence of T2 dark curvilinear lines within the high signal silicone gel known as the "linguine" sign (Fig. 3 on page 19). Although CT is not a preferred modality for evaluation, incidental findings of implant rupture can occasionally be identified by CT. (Fig. 4 on page 19). An additional sign of intracapsular rupture includes the "droplet" sign which can be seen in approximately one fourth of ruptures (2). (Fig. 5 on page 20) Additional "keyhole" or "teardrop" signs have also been described which refers to the T2 dark linear focus of focal separation of the envelope from the capsule creating focal involution of the inner envelope in the shape of a keyhole or teardrop. (Fig. 6 on page 21) Of note is the presence of normal infoldings of the inner silicone containing envelope which can be noted on MR which are termed radial folds. This entity is important to identify and not confuse it with implant rupture. (Fig. 7 on page 21) Extracapsular rupture will be demonstrated by silicone material which is identified with either silicone sensitive or suppresed sequences outside the confines of the external fibrous capsulre. ( Fig. 8 on page 21; Fig. 9 on page 23 ) Page 5 of 37

6 Fig. 3: Axial STIR water saturated MR image of a double lumen implant demonstrates extravasation of the silicone in the saline lumen as well as the linguine sign indicative of intracapsular rupture. Radial fold noted on the contralateral side. References: N. B. Ibrahim; Diagnostic Radiology, Lahey Clinic, Burlington, UNITED STATES OF AMERICA Page 6 of 37

7 Fig. 9: Axial STIR water saturated image demonstrating extravasated silicone oustide the confines of the fibrous capsule indicative of extracapsular rupture. References: N. B. Ibrahim; Diagnostic Radiology, Lahey Clinic, Burlington, UNITED STATES OF AMERICA Implant Infection Fluid collections surrounding implants are common in the post operative period. (Fig. 10 on page 23) The presence of fluid itself is nonspecific. Infection is not an uncommon implant complication. Women may experience abscess formation as well as inflammation of the breast parenchyma. Both puerperal and non puerperal mastitis can be seen which can be both related to the breast implants (silicone mastitis) or unrelated (5). (Fig. 11 on page 24) MRI examination can be helpful to evaluate the extent of inflammation. Page 7 of 37

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9 Fig. 11: 37 year old woman with 6 year history of saline implants presented with fever, breast erythema and pain. LMLO view demonstrates increased density of the breast parenchyma secondary to mastitis. References: N. B. Ibrahim; Diagnostic Radiology, Lahey Clinic, Burlington, UNITED STATES OF AMERICA Fat Necrosis Given the vast numbers of breast surgery done today, fat necrosis as a sequalae of surgery is readily seen. Fat necrosis is more often seen after breast conserving surgery with or without radiation, however may also be noted after breast implantation. (9). Presence of oil cysts is pathognomonic for the presence of fat necrosis. Ultrasound examination of fat necrosis may appear as an anechoic mass, or mass with complex echogenic bands or debris. (9). MRI examination can demonstrate enhancing lesions adjacent to the implant which usually is noted to decrease over time and eventually resolve. (Fig. 12 on page 26) These findings are nonspecific and maybe difficult to differentiate from neoplastic process (9). Page 9 of 37

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11 Fig. 12: Sagittal fat saturated T1 contrast enhanced image demonstrates ring like enhancement with central signal void indicative of fat necrosis.this area of enhancement was noted to decrease over time. References: N. B. Ibrahim; Diagnostic Radiology, Lahey Clinic, Burlington, UNITED STATES OF AMERICA Anaplastic Large Cell Lymphoma According to the U.S. Food and Drug Administration bulletin in 2011, there are approximately 60 case reports of Anaplastic Large Cell Lymphoma (ALCL) in women with breast implants worldwide. ALCL has been noted to be present in women with both saline and silicone implants. No prospective cohort study has been completed to evaluate the association between breast implants and ALCL. Although the risk appears low, more research is needed to further evaluate. A case of ALCL was noted at our institution. A 59 year old woman with a 15 year history of bilateral saline imlpants presented for routine mammogram follow up. She did note that over the past year prior to presentation she had lost weight and felt her right breast felt hard. Mammography demonstrated an ill defined asymmetric density with mass effect on the saline imlpant. Further workup with subsequent biopsy yielded ALCL. ( Fig. 13 on page 28; Fig. 15 on page ; Fig. 16 on page 30; Fig. 17 on page 32; Fig. 18 on page 34; Fig. 19 on page 34) Page 11 of 37

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13 Fig. 13: RMLO mammogram demonstrating mass in the upper breast demonstrating mass effect on the saline implant. This mass was biopsy proven Anaplastic Large Cell Lymphoma. References: N. B. Ibrahim; Diagnostic Radiology, Lahey Clinic, Burlington, UNITED STATES OF AMERICA Page 13 of 37

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15 Fig. 16: T1 fat saturated post contrast sagittal image demonstrates avid enhancement of the right breast mass adjacent to the implant. References: N. B. Ibrahim; Diagnostic Radiology, Lahey Clinic, Burlington, UNITED STATES OF AMERICA Images for this section: Page 15 of 37

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17 Fig. 1: Left LMLO mammogram demonstrates collapsed saline implant. Page 17 of 37

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19 Fig. 2: Right LMLO view of a silicone implant demonstrates extravasated silicone outside the confines of the breast implant indicative of extracapsular rupture. Fig. 3: Axial STIR water saturated MR image of a double lumen implant demonstrates extravasation of the silicone in the saline lumen as well as the linguine sign indicative of intracapsular rupture. Radial fold noted on the contralateral side. Page 19 of 37

20 Fig. 4: Incidental note made of the linguine sign on PET/CT indicative of intracapsular rupture. Page 20 of 37

21 Fig. 5: Axial STIR water saturated weighted image demonstrating the droplet sign as well as a keyhole sign indicative of intracapsular rupture. Fig. 6: Axial STIR image demonstrating multiple keyhole signs of intracapsular rupture Fig. 7: Axial STIR water saturated weighted image of the breast demonstrating radial folds which should not be confused with rupture. Page 21 of 37

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23 Fig. 8: Sagittal STIR image demonstrates extravasated silicone indicative of extracapsular rupture. Fig. 9: Axial STIR water saturated image demonstrating extravasated silicone oustide the confines of the fibrous capsule indicative of extracapsular rupture. Page 23 of 37

24 Fig. 10: Axial STIR image demonstrating perimplant fluid. Page 24 of 37

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26 Fig. 11: 37 year old woman with 6 year history of saline implants presented with fever, breast erythema and pain. LMLO view demonstrates increased density of the breast parenchyma secondary to mastitis. Page 26 of 37

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28 Fig. 12: Sagittal fat saturated T1 contrast enhanced image demonstrates ring like enhancement with central signal void indicative of fat necrosis.this area of enhancement was noted to decrease over time. Page 28 of 37

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30 Fig. 13: RMLO mammogram demonstrating mass in the upper breast demonstrating mass effect on the saline implant. This mass was biopsy proven Anaplastic Large Cell Lymphoma. Fig. 14: Ultrasound of the right breast mass demonstrating marked heterogeneity and mass effect on the saline implant. The mass was biopsied by ultrasound and yielded ALCL. Page 30 of 37

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32 Fig. 16: T1 fat saturated post contrast sagittal image demonstrates avid enhancement of the right breast mass adjacent to the implant. Page 32 of 37

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34 Fig. 17: Angiomap post contrast sagittal image demonstrating areas of rapid enhancement within the right breast mass noted to be ALCL. Fig. 18: Angiomap post contrast axial image demonstrating enhancing breast mass which was noted to be ALCL adjacent to the saline implants. Page 34 of 37

35 Fig. 19: Enhancement curve for the right breast mass demonstrates rapid enhancement and washout. This mass was proven by biopsy to be Anaplastic Large Cell lymphoma. Page 35 of 37

36 Conclusion Breast implantation is common worldwide. Radiologists will inevitably encounter women with implants in both screening and diagnostic settings. Knowledge of the common implant complications and the preferred modality of evaluation are important for accurate diagnosis and timely subsequent treatment. Personal Information N.B. Ibrahim Lahey Clinic Diagnostic Radiology 41 Mall Road, Burlington, MA References 1. U.S. Food and Drug Administration. FDA Update on the Safety of Silicone Gel-Filled Breast Implants. U.S. Food and Drug Administration Website. MedicalDevices/ProductsandMedicalProcedures/ImplantsandProsthetics/ BreastImplants/ucm htm. Published June Accessed Jan 24th, Azavedo E, Bone B. Imaging breasts with silicone implants. Eur Radiol 1999; 9: U.S. Food and Drug Administration. Anaplastic Large Cell Lymphoma (ALCL) in Women in Breast Implants: Preliminary FDA Findings and Analyses. U.S. Food and Drug Administration Website. MedicalDevices/ProductsandMedicalProcedures/ImplantsandProsthetics/ BreastImplants/ucm htm. Published January Accessed Jan 24th, Venkataraman S, Hines N, Slanetz PJ. Challenges in mammography: part 2, multimodality review of breast augmentation--imaging findings and complications.american Journal of Roentgenology. 2011;197(6):W Page 36 of 37

37 5. Huch RA, Kunzi W, Debatin JF, Wiesner W, Krestin GP. MR imaging of the augmented breast. Eur Radiol 1998; 8: Harris KM, Ganott MA, Shestak KC, Losken HW, Tobon H. Silicone implant rupture: detection with US. Radiology 1993; 187: O'Toole M, Caskey CI. Imaging spectrum of breast implant complications: mammography, ultrasound, and magnetic resonance imaging. Semin Ultrasound CT MR 2000; 21: Berg WA, Caskey CI, Hamper UM, et al. Diagnosing breast implant rupture with MR imaging, US, and mammography. RadioGraphics 1993; 13: Chala LF, de Barros N, de Camargo Moraes P, et al. Fat necrosis of the breast: mammographic, sonographic, computed tomography, and magnetic resonance imaging findings. Curr Probl Diagn Radiol 2004; 33: Page 37 of 37