Augmentation mammaplasty is the most common aesthetic procedure performed by American Society of Plastic Surgeons members.1 Breast implants come with their own set of complications, such as asymmetry, malposition/malrotation, seroma, periprosthetic infection, rupture/deflation, capsular contracture, pain, and other cosmetic concerns.
In North America, silicone gel–filled implants have dominated the market since their inception in 1963, with saline implants seeing a resurgence after the 1992 U.S. Food and Drug Administration moratorium on silicone-gel filled implants.2 Textured silicone implants were introduced in the mid-1980s, replacing polyurethane foam–covered implants, which were removed from the market in 1987. After the 1992 U.S. Food and Drug Administration moratorium was lifted in 2007, textured silicone implants became readily available for use in breast augmentation. The textured surface has the ability to adhere to the surrounding soft-tissue pocket, which is thought to be more pronounced with the more aggressively textured Allergan (Allergan, Inc., Irvine, Calif.) Biocell implants.3–6 Textured implants may provide better control of implant position, thus permitting favorable conditions for the use of anatomical implants.3 , 6 Multiple studies have demonstrated a reduction in capsular contracture rates when comparing textured to smooth implants.7–9 There has also been much discussion around the link between Biocell implants and double capsules and late seromas.10–15 Despite this, there remains a deficiency in the literature as to whether the evolution of textured implants has had an impact on implant longevity, symptoms leading to implant removal, and intraoperative findings at explantation. In this article, we explore the specifics regarding explanted implant types from the senior author’s (N.J.C.) aesthetic practice, with the goal of learning about implant longevity, reasons for explantation and clinical presentation, and intraoperative findings at explantation.
PATIENTS AND METHODS
This is a retrospective, event-based study. Data were extracted on all breast implants that were explanted between January of 2005 and April of 2017. The senior author (N.J.C.) performed all explantations and secondary placements at his aesthetic practice during this period. Patients with saline, smooth gel, Biocell textured, and any other textured gel implant originally placed for aesthetic reasons were included. Gel-saline, textured saline, and any implants placed for reconstructive purposes were excluded. Many implants were originally placed by other surgeons and, as a result, the denominator for each implant type is not known. We can only establish reasons associated with explantation, intraoperative findings, and frequency of removal.
Patient records were retrospectively reviewed for the following: age at explantation, medical history and smoking status, date of implantation and explantation, implant type, incision, original plane of placement, implant volume, implant longevity, reason for explantation, and intraoperative findings at explantation.
Data were analyzed using descriptive statistics and, where appropriate, an analysis of variance was used to determine whether time to explantation or time to rupture was significantly different between Biocell, saline, smooth gel, and other textured gel implants. A t test was performed to compare time to explantation between Biocell and all other implant types. A chi-square test was used to determine statistical significance for complications and intraoperative findings between implant types. A multiple linear regression analysis was performed to investigate confounding variables such as implant type, incision, plane of placement, age at explantation, smoking status, and implant volume. A Bonferroni correction was applied to adjust for the number of tests performed; a value of p < 0.0014 was determined to be significant. Statistical analysis was performed with StatsModels (Python Software Foundation, Wilmington, Del.).
This study was approved by the Ethics Committee at the University of British Columbia (H17-00876). Patient consent was not required.
During the 13-year study period, a total of 248 patients underwent explantation performed by the senior author, and a total of 552 breast implants were removed. Of the 552 implants explanted, 14 implants were removed as a unilateral procedure, and 269 implants were explanted along with the contralateral implant. Of the 248 patients in the study, 219 patients underwent explantation once, 24 patients underwent explantation twice, four patients underwent explantation three times, and one patient underwent explantation four times; all of these procedures were performed by the senior author. The average patient age was 39.7 years (range, 20 to 85 years). Our study population was generally healthy. Two hundred sixteen patients did not have a systemic disease. The diseases represented in the remaining patients are listed in Table 1. Fifty-nine patients admitted to smoking any amount of cigarettes at the time of explantation. Fifty-four smokers underwent explantation once and five smokers underwent explantation more than once (all procedures performed by the senior author).
During the study period, 249 saline, 147 smooth gel, five gel-saline, 123 Biocell textured, eight textured saline, and 20 other textured implants were explanted. The 20 textured implants constituting the “other” study group consisted of six Mentor (Mentor Corp., Santa Barbara, Calif.) Siltex, four CUI (CUI, Carpinteria, Calif.) MicroCell textured, eight Eurosilicone (Eurosilicone SAS, Apt, France), and two Laboratoire Arian (Laboratoire Arian, Mougins, France) textured implants. One hundred twenty-four implants were originally placed in subglandular position, 347 were placed in retropectoral position, and 81 were dual plane. Two hundred twenty-six implants were originally placed through an inframammary fold incision, 162 were placed through a periareolar incision, 100 were placed through a transaxillary approach, and 64 were placed in conjunction with a mastopexy. The average implant volume explanted in our study was 344.4 ml (range, 130 to 800 ml). Because of small sample size, the textured saline and gel-saline implants were excluded from the analysis for the remainder of the study, leaving 539 implants explanted from 245 patients in total.
Figure 1 describes the relationship between implant longevity in days and implant type. To allow for equal exposure time during the study period, the longevity data were limited to the time that all breast implant types were available on the market. In our data set, the first Biocell implant was originally placed in 2001; thus, all implants placed earlier than this were removed for the time-to-explantation analysis. Two hundred twenty-three implants that were placed after January of 2001 were explanted from 197 patients during the study period: 85 saline, 68 smooth gel, 62 Biocell, and eight other textured gel implants. When looking at all causes for explantation, the average time from placement to explantation was 7.5, 5.6, 4.9, and 4.0 years for saline, other textured, smooth gel, and Biocell textured implants, respectively (p = 3.25e-08). Furthermore, a t test was performed to compare the mean time to explantation for Biocell implants, 4.0 years, to that of all implants in the study period combined, 6.4 years; this showed that Biocell implants were explanted significantly sooner than saline, smooth gel, and other textured implants combined (p = 5.54e-07).
Table 2 shows the proportion of implants removed that were associated with implant performance failure. Implants were classified as exhibiting performance failure, based on either the presenting reason for explantation or findings at surgery. For the purpose of this study, implant performance failure was defined to include malposition, malrotation, seroma, rippling, Baker grade III/IV capsular contracture, rupture, pain, double capsule, and any other abnormal intraoperative findings. Implants not considered to exhibit performance failure were those removed for size change in isolation, asymmetry or cosmetic deformity not in relation to any identifiable pathologic condition, ptosis or mastopexy, patient desire to remove implants despite no identifiable disease, psychosocial reasons, incidental mass unrelated to implant, periprosthetic infection, and in all cases where no identifiable intraoperative pathologic condition related to the implant was found. As shown in Table 2, implant performance failure was seen with 105 of 123 Biocell implants, 15 of 20 other textured gel implants, 143 of 249 saline implants, and 74 of 147 smooth gel implants (chi-square test, p = 7.25e-09). Biocell implants had the highest rate of implant performance failure at 85.4 percent, followed by other textured gel, saline, and smooth gel at 75.0, 57.4, and 50.3 percent, respectively (Table 2).
Table 3 outlines the number of implants that presented as painful implants not attributed to Baker grade IV capsular contracture. Twenty-six of 123 Biocell implants presented as painful implants, whereas for all other implants in the study, only six of 416 implants presented with pain (chi-square test, p = 2.71e-15). In other words, 21.1 percent of explanted Biocell implants presented with pain, compared to 1.4 percent of all other implant types explanted during the study period (Table 3).
Table 4 highlights intraoperative findings at explantation. Forty-five of 123 Biocell implants were found to have double capsules at explantation, and this was not seen with any other implant type during the study period (chi-square test, p = 5.85e-37). For the purpose of this study, a finding of double capsule is defined as a nonadherent or partially adherent implant with capsule formation on both the implant and the surrounding tissue. Of the 45 double capsules seen with Biocell implants, nine double capsules were partially adherent and 36 were nonadherent. Figure 2 shows an example of nonadherent double capsules at explantation in a 39-year-old woman with Allergan Biocell Style 410 implants who presented with a unilateral, painful, ruptured left implant 6 years after implantation. The patient did not complain of symptoms involving the right breast implant; however, it is clear from the clinical photographs that both implants have bottomed-out, reflecting the nonadherent nature of these double capsules. As shown in Table 4, late seromas were discovered in seven of 123 Biocell implants, whereas only three late seromas were seen in the 416 other implant types explanted during the study period (chi-square test, p = 0.0013); one smooth gel and two other textured implants accounted for the three late seromas found in all other implant types. The number of implants found to be ruptured at the time of explantation did not differ statistically between the implant types, with ruptures occurring in 27 of 249 saline, 27 of 147 smooth gel, 21 of 123 Biocell, and one of 20 other textured implants (chi-square test, p = 0.08). Of these, 12 Biocell and eight smooth gel implants were silent ruptures (Table 4).
Figure 3 illustrates the time to rupture for each implant type in days, excluding the one ruptured other textured gel implant. Biocell implants had a shorter time to rupture at 4.7 years compared to 8.4 and 8.1 years for saline and smooth gel implants, respectively; the only other textured gel implant that ruptured during the study period did so at 0.8 year (p = 0.004). This relationship did not reach statistical significance given that we had to accept a smaller than usual value of p = 0.0014 to adjust for multiple comparisons throughout the study.
To test for confounding variables that may have contributed to our results, we ran a multiple linear regression analysis for every statistical test performed. We looked at implant type, incision, plane of implant placement, age at explantation, smoking status, and volume of implant (in milliliters). Only the implant type was found to have a significant effect for each result presented above (p < 0.0014).
There are many variables that factor into the decision as to which breast implant is right for each patient. Although this discussion has traditionally focused on saline versus silicone gel implants, more recently the conversation has shifted toward textured implants. The evolution of texturing has been shown to reduce the rate of capsular contracture, especially when placed in the subglandular plane.7 , 8 , 16 Danino and colleagues have demonstrated at the ultrastructural level the adhesive effect of textured breast implants on the surrounding capsule, which is enhanced by more aggressively textured implants.4 This adhesive effect allows for better control of implant position within the pocket, as evidenced by a 5.2 percent malrotation rate in a recent review of 440 patients receiving subglandular breast augmentation with Allergan’s 410 implant.14 Research is lacking, however, as to whether the evolution of textured implants has affected implant longevity. It is unclear whether textured implants are being explanted for reasons related to failure of the implant itself.
Here, we show that Biocell implants have the shortest longevity and are more frequently associated with implant performance failure compared to saline, smooth gel, and other nonaggressively textured implants. Furthermore, of the 123 Biocell implants explanted, 26 were removed primarily because of pain. This unusual presentation has not previously been linked to Biocell implants. Intraoperatively, these 26 implants had the following findings: rupture (n = 5), rupture and double capsule (n = 2), nonadherence and malrotation (n = 2), partial adherence and malrotation (n = 1), nonadherence (n = 4), partial adherence (n = 1), nonadherent double capsule (n = 5), partially adherent double capsule (n = 2), and no identifiable intraoperative abnormality (n = 3). The final painful Biocell implant was initially diagnosed with grade IV capsular contracture and malrotation but, intraoperatively, was found to have a large abnormal capsular overgrowth indenting the implant and corresponding with the painful site. Biopsy specimens of the capsular overgrowth were reported to consist of periprosthetic fibrous tissue. The one painful Mentor Siltex implant had a nonadherent inflammatory capsule and late seroma intraoperatively. Of the five smooth gel implants presenting with pain, three were without intraoperative abnormality, one had a scarred capsule, and one implant had migrated from the retropectoral into the subglandular plane. Given these intraoperative findings, we postulate the cause of pain associated with textured implants to relate to partial adherence or failed adherence of the implant with associated inflammation. An association between biofilm and textured implants exists,17 , 18 and Hu and colleagues have shown an increased inflammatory response and T-cell hyperplasia with textured implants.18 It is likely that biofilm and inflammation underlie the cause of the intraoperative findings seen with painful textured implants in this study.
Of the 123 Biocell implants explanted in our study, 45 had double capsules and seven had late seromas. Double capsules were first linked to Biocell textured implants by Hall-Findlay in a retrospective case series of patients undergoing breast augmentation or augmentation mastopexy.10 Of the 105 patients who received Biocell textured implants in her study, 14 patients were found to have double capsules; this phenomenon was not observed with any other implant type, and seemed to be independent of plane of placement or implant shape.10 The significance of double capsules and late seromas has been questioned, as a panel of experts has suggested that the benefits of Biocell implants outweigh this rare phenomenon.11 , 12 However, little is known as to how double capsules present and whether they are problematic for the patient. Of the 45 double capsules in our study, 13 presented without any symptomatology, whereas the others presented with rupture (n = 6), Baker grade III/IV capsular contracture (n = 6), nonadherence with or without a deformity (n = 5), rippling (n = 5), double capsule on imaging (n = 1), or pain or an “uncomfortable feeling” (n = 9). We do not understand the clinical significance of “silent” double capsules, and their presence suggests that the incidence of double capsules with Biocell implants is greater than previously reported.6 , 12
In our study, all 45 implants with double capsule and seven implants with late seromas were Biocell; in contrast, no other implant type had a double capsule, and late seromas were observed with two nonaggressively textured implants. One smooth gel implant from a patient who had previous implants of unknown type was found to have a late seroma. This suggests that the underlying cause of double capsules may be related to adhesion failure of the aggressive surface texturing in Biocell implants, whereas the association of late seromas may be related more to textured implants in general. With the exception of a double capsule linked to one Mentor Siltex implant in a review article, all previously documented cases of double capsule have occurred with Biocell implants.2 , 10 , 14 , 15 Our report adds strength to the association between aggressively textured implants and double capsules, and textured implants and late seromas. Although the exact cause may involve a biofilm or subclinical infection component,6 , 19 , 20 Giot and colleagues propose mechanical delamination of the periprosthetic capsule resulting in separation of the capsule into two layers.20 Recently, Danino et al. have provided further evidence to strengthen this theory, as biofilm formation may trigger an immune response that weakens capsule strength, predisposing to extracellular matrix delamination and double capsule formation.21
Breast implant–associated anaplastic large-cell lymphoma (ALCL) is a patient safety concern, with a recent incidence estimate of 2.03 per 1 million patient-years in patients with textured breast implants.22 Although the underlying cause of breast implant–associated ALCL remains elusive, it is likely attributable to a complex interaction of bacterial biofilm, chronic inflammation, and genetic predisposition.17 , 18 , 23 , 24 Textured surfaces have been shown to increase the biofilm burden of an implant.17 , 18 In vitro studies have also demonstrated a link between bacterial biofilm, T-cell hyperplasia, and an increased inflammatory response with textured implants.18 More recently, Hu and colleagues compared 26 breast implant–associated ALCL–positive breast implant capsules to 62 nontumor capsules and found a distinct microbiome associated with breast implant–associated ALCL–positive capsules.24 Although we do not report any cases of breast implant–associated ALCL in our study, we show that Biocell implants are associated with an array of clinical presentations and intraoperative findings, such as pain, late seroma, and double capsule, that are likely to arise from or perpetuate the chronic inflammatory state. In the genetically predisposed patient, it is possible that these clinical and intraoperative findings could lead to the development of breast implant–associated ALCL, but further studies are needed to confirm this relationship.
This study was limited by its retrospective nature and relatively small sample size. Our data did not account for any revisions or explantations that the patient may have received before their explantation performed by the senior author. This may be a confounding variable, given that the rate of reoperation following revision breast augmentation is higher than that for a primary breast augmentation2 , 25–27; however, this confounding variable would have been distributed across all implant types in our study. Most implants explanted in this study were originally placed in North America; however, because many of the implants were placed by other surgeons, we are unable to comment on the storage condition of these implants before implantation or whether the implants were placed before the manufacturer’s expiration date. Different surgeons may have used different perioperative protocols and techniques that could have affected the clinical presentation of results. Given the senior author’s expertise in dealing with difficult breast cases, our results may have a selection bias, as our cohort of patients may have self-selected for the senior author’s practice. Our comments on longevity reflect the time to explantation, not the time at which the patient presented with problematic clinical findings. Therefore, it is possible that some of the time-to-explantation data could be inflated if other factors prevented the patient from obtaining their operation. Finally, we do not have the denominator for each implant type, or total number of implant types placed.
It is difficult to compare our Biocell results to that observed in the literature, given differences in study design. There are two industry-funded Core Studies with long-term follow-up investigating Biocell implant outcomes.25 , 27 Maxwell and colleagues looked at 492 and 156 women undergoing breast augmentation and revision augmentation with Allergan’s 410 Biocell anatomical implants, respectively.27 Follow-up at 10 years was 65.8 and 55.3 percent in the augmentation and revision augmentation cohorts, respectively.27 Over the 10-year period, the risk rate was 29.7 and 47.3 percent for reoperation, 4.5 and 5.2 percent for breast pain, 4.7 and 9.1 percent for implant malposition, and 1.6 and 3.2 percent for seroma in the augmentation and revision augmentation groups, respectively.27 The incidence of late seroma was 0.4 percent in the augmentation cohort.27
With respect to nonanatomical Biocell implants, Spear and colleagues report 10-year results on 455 breast augmentation and 147 revision augmentation patients, of which 41.0 and 43.0 percent were with Biocell implants, respectively.25 Compliance with follow-up at 10 years was 66.7 and 62.2 percent for the breast augmentation and revision augmentation groups, respectively.25 Over the 10-year period, the risk rate was 36.1 and 46.0 percent for reoperation, 11.5 and 11.7 percent for breast pain, 6.8 and 6.0 percent for implant malposition, and 1.8 and 6.0 percent for seroma in the augmentation and revision augmentation groups, respectively.25 There were four late seromas in the breast augmentation and revision augmentation groups combined.25 However, this Core Study was not specifically designed to capture outcomes related to texturing.25 Considered together, along with the small sample size of Biocell implants and poor compliance rates with follow-up, one could argue that the Core Studies discussed above do not provide sufficient data on safety specific to Biocell implants.
This is the first numerator study to compare Biocell implants to other implant types in a single surgeon’s practice. Many denominator studies, such as the Core Studies, are industry funded and have a relatively small sample size, with inconsistent or short follow-up.25–29 Denominator studies likely underestimate rates of complication because of incomplete tracking of patients. We feel that numerator studies capture more problems with a device at the expense of not being able to estimate the complication frequency. Furthermore, numerator studies allow for the investigator to capture the cohort of individuals who have left their original surgeon to seek a second opinion.
Here, we present the first study comparing explantation data for saline, smooth gel, Biocell, and other less aggressively textured implants. Our results show that Biocell implants have the shortest time to explantation and are more frequently associated with problems related to implant performance failure, specifically pain. Our findings strengthen the previous association between Biocell implants and double capsules and late seromas.10 , 14 This information may guide patients and plastic surgeons when evaluating the safety and effectiveness of different implant types.
This study was funded by a 2016 University of British Columbia Division of Plastic Surgery Academic Research Grant. Statistical analysis was performed by Karey Shumansky from the Applied Statistics and Data Science Group through the University of British Columbia Department of Statistics.
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5. Abramo AC, De Oliveira VR, Ledo-Silva MC, De Oliveira EL. How texture-inducing contraction vectors affect the fibrous capsule shrinkage around breasts implants? Aesthetic Plast Surg. 2010;34:555–560.
6. Maxwell GP, Scheflan M, Spear S, Nava MB, Hedén P. Benefits and limitations of macrotextured breast implants and consensus recommendations for optimizing their effectiveness. Aesthet Surg J. 2014;34:876–881.
7. Barnsley GP, Sigurdson LJ, Barnsley SE. Textured surface breast implants in the prevention of capsular contracture among breast augmentation patients: A meta-analysis of randomized controlled trials. Plast Reconstr Surg. 2006;117:2182–2190.
8. Wong CH, Samuel M, Tan BK, Song C. Capsular contracture in subglandular breast augmentation with textured versus smooth breast implants: A systematic review. Plast Reconstr Surg. 2006;118:1224–1236.
9. Liu X, Zhou L, Pan F, Gao Y, Yuan X, Fan D. Comparison of the postoperative incidence rate of capsular contracture among different breast implants: A cumulative meta-analysis. PLoS One 2015;10:e0116071.
10. Hall-Findlay EJ. Breast implant complication review: Double capsules and late seromas. Plast Reconstr Surg. 2011;127:56–66.
11. Bengtson B, Brody GS, Brown MH, et al; Late Periprosthetic Fluid Collection after Breast Implant Working Group. Managing late periprosthetic fluid collections (seroma) in patients with breast implants: A consensus panel recommendation and review of the literature. Plast Reconstr Surg. 2011;128:1–7.
12. Maxwell GP, Brown MH, Oefelein MG, Kaplan HM, Hedén P. Clinical considerations regarding the risks and benefits of textured surface implants and double capsule. Plast Reconstr Surg. 2011;128:593–595.
13. Spear SL, Rottman SJ, Glicksman C, Brown M, Al-Attar A. Late seromas after breast implants: Theory and practice. Plast Reconstr Surg. 2012;130:423–435.
14. Lista F, Tutino R, Khan A, Ahmad J. Subglandular breast augmentation with textured, anatomic, cohesive silicone implants: A review of 440 consecutive patients. Plast Reconstr Surg. 2013;132:295–303.
15. Park BY, Lee DH, Lim SY, et al. Is late seroma a phenomenon related to textured implants? A report of rare complications and a literature review. Aesthetic Plast Surg. 2014;38:139–145.
16. Schaub TA, Ahmad J, Rohrich RJ. Capsular contracture with breast implants in the cosmetic patient: Saline versus silicone. A systematic review of the literature. Plast Reconstr Surg. 2010;126:2140–2149.
17. Jacombs A, Tahir S, Hu H, et al. In vitro and in vivo investigation of the influence of implant surface on the formation of bacterial biofilm in mammary implants. Plast Reconstr Surg. 2014;133:471e–480e.
18. Hu H, Jacombs A, Vickery K, Merten SL, Pennington DG, Deva AK. Chronic biofilm infection in breast implants is associated with an increased T-cell lymphocytic infiltrate: Implications for breast implant-associated lymphoma. Plast Reconstr Surg. 2015;135:319–329.
19. Allan JM, Jacombs AS, Hu H, Merten SL, Deva AK. Detection of bacterial biofilm in double capsule surrounding mammary implants: Findings in human and porcine breast augmentation. Plast Reconstr Surg. 2012;129:578e–580e.
20. Giot JP, Paek LS, Nizard N, et al. The double capsules in macro-textured breast implants. Biomaterials 2015;67:65–72.
21. Danino MA, Nizard N, Paek LS, Govshievich A, Giot JP. Do bacteria and biofilm play a role in double-capsule formation around macrotextured implants? Plast Reconstr Surg. 2017;140:878–883.
22. Doren EL, Miranda RN, Selber JC, et al. U.S. epidemiology of breast implant-associated anaplastic large cell lymphoma. Plast Reconstr Surg. 2017;139:1042–1050.
23. Bizjak M, Selmi C, Praprotnik S, et al. Silicone implants and lymphoma: The role of inflammation. J Autoimmun. 2015;65:64–73.
24. Hu H, Johani K, Almatroudi A, et al. Bacterial biofilm infection detected in breast implant-associated anaplastic large-cell lymphoma. Plast Reconstr Surg. 2016;137:1659–1669.
25. Spear SL, Murphy DK; Allergan Silicone Breast Implant U.S. Core Clinical Study Group. Natrelle round silicone breast implants: Core Study results at 10 years. Plast Reconstr Surg. 2014;133:1354–1361.
26. Stevens WG, Calobrace MB, Harrington J, Alizadeh K, Zeidler KR, d’Incelli RC. Nine-year Core Study data for Sientra’s FDA-approved round and shaped implants with high-strength cohesive silicone gel. Aesthet Surg J. 2016;36:404–416.
27. Maxwell GP, Van Natta BW, Bengtson BP, Murphy DK. Ten-year results from the Natrelle 410 anatomical form-stable silicone breast implant core study. Aesthet Surg J. 2015;35:145–155.
28. Derby BM, Codner MA. Textured silicone breast implant use in primary augmentation: Core data update and review. Plast Reconstr Surg. 2015;135:113–124.
©2018American Society of Plastic Surgeons
29. Maxwell GP, Van Natta BW, Murphy DK, Slicton A, Bengtson BP. Natrelle style 410 form-stable silicone breast implants: Core Study results at 6 years. Aesthet Surg J. 2012;32:709–717.