Influence of some operative and postoperative factors on capsular contracture around breast prostheses.

In a follow-up of 490 patients with breast implants, neither the size of the prosthesis nor the nature of the surgical procedure (simple augmentation mammaplasty or after subcutaneous mastectomy) increased the incidence of capsular contracture. Hematoma or infection were followed by a higher incidence of capsular contracture. Drainage with suction and the instillation of steroid around the prostheses seemed to be effective in reducing the incidence of capsular contracture. In the steroid-treated group, the need for open surgical treatment was reduced. The recurrence rate after closed capsulotomy, or open capsulotomy, was not significantly different from that following the more extensive procedure of capsulectomy.     

Capsular contracture after breast reconstruction with silicone-gel and saline-filled implants: a 6-year follow-up

A major problem after breast reconstruction with augmentation mammaplasty is contracture of the fibrous capsule around the prosthesis. In a series of 72 breasts in 65 women, silicone-gel and saline-filled implants were randomly selected prior to breast reconstruction. The results were judged with respect to consistency, tenderness, wrinkles, and sounds by two independent plastic surgeons according to the breast augmentation classification (BAC) and by the patients themselves. Capsular contracture was found by the surgeons in 50 percent of the gel implant group and in 16 percent of the saline implant group, which is in conformity with the results of the follow-up 5 years earlier. The incidence of deflation was 16 percent in the saline group and occurred in different sizes of both overinflated and underinflated prostheses. The degree of slow leakage from saline implants will be discussed. Despite the high rate of contractures in the gel group, 85 percent of all patients were satisfied with the result of the reconstruction.     

Capsular contracture in silicone gel and saline-filled breast implants after reconstruction

Comparisons between results with randomly allotted silicone-gel and saline-filled prostheses in breast reconstruction after mastectomy led to the following conclusions. Neither prosthesis type is ideal. Leakage from saline-filled implants occurred in 2 of the 37 implants, with resultant deflation. Silicone prostheses had a significantly higher rate of capsular contracture [surgeon's evaluation: 54 percent capsular contracture for silicone-gel compared with 20 percent for saline-filled prostheses (p = 0.006); patients' evaluation for the same figures: 54 percent compared with 29 percent (p = 0.03)]. Other authors have shown the presence of silicone in the tissue around silicone-gel-filled silicone implants, but less or none around saline-filled silicone implants. Since the only difference between the two groups was the randomly allotted implants, we assume that the free silicone around silicone-gel-filled prostheses is the major cause of capsular contracture. Since the saline-filled implants showed a 20 percent capsular contracture rate, there could be other causes of capsular contracture in this study. For prevention of contracture, improved implant encapsulation and use of a less reactive filling substance seem to offer possibilities. Surgical technique should aim to preserve the integrity of the prosthesis.     

Variability in the properties of silicone gel breast implants.

Several generations of silicone gel breast implants have been produced by implant manufacturers. The primary material usually viewed as the base material in the manufacture of implants is polydimethylsiloxane. Polymeric reactions are notorious for their variability and nonuniformity. The elastomer used in different types of implants can have vastly different properties. Furthermore, the material properties associated with a particular type of implant can vary considerably from one lot to the next. Considering the various designs, styles, and manufacturing techniques associated with silicone gel implants, knowledge of the original properties of the implants before implantation is important in determining the effects of aging in vivo. This study was conducted to investigate differences in key mechanical and chemical properties of silicone gel breast implant materials. The two types of implants chosen for analysis were Silastic I and Silastic II control implants. Material property data were determined for both types of controls and significant differences were found in their values. Lot-to-lot variability was also investigated and found to be significant.     

Comparative experience with smooth and polyurethane breast implants using the Kaplan-Meier method of survival analysis.

Smooth-walled silicone implants have been widely used in breast surgery. Capsular contracture, causing undesirable firmness and spherical deformity, has been a common problem. Recent studies suggest that polyurethane-covered breast implants are associated with a lower incidence of capsular contracture. The statistical methodology employed in some of these studies, however, may be subject to criticism. Between July of 1984 and June of 1990 (72 months), 427 polyurethane breast implants were used in 279 patients and 439 smooth prostheses were used in 250 patients for a variety of aesthetic and reconstructive procedures. The occurrence of capsular contracture was carefully monitored and then analyzed using the Kaplan-Meier method of survival analysis. This method is particularly well suited to analysis of these types of clinical data because it allows for the fact that contractures occur at varying intervals after surgery and that follow-up of patients is incomplete. The probability of capsular contracture with smooth-walled prostheses was found to be significantly greater than with polyurethane-covered implants in each group of patients studied (p less than 0.05). Other complications occurred at a similar rate regardless of prosthesis type. This study supports the belief that polyurethane breast implants have a lower contracture rate; furthermore, it introduces the Kaplan-Meier method for analyzing the outcome of alternative plastic surgical therapies.     

Ten-year review of a prospective randomized controlled trial of textured versus smooth subglandular silicone gel breast implants

Although textured silicone breast implants have been shown to reduce the incidence of capsular contracture, there is little evidence if this effect is maintained in the long term. It has been 10 years since the double-blind randomized trial in which 53 patients received either Mentor smooth (26) or textured silicone gel implants (27). Of the 14 patients who were not known to have developed a contracture in the smooth group, 11 were reviewed. Three had bilateral contractures. In the textured group, 18 of the 24 patients not known to have contractures were reviewed. None had developed contractures. At 10 years, the incidence of capsular contracture was 65 percent of patients with smooth implants (an increase of 6 percent on the 3-year results) and 11 percent for the textured implant patients (no change on the 3-year results). A database containing the details of 1100 patients reinforces these results by examining the differences in contracture rates of textured, smooth, and polyurethane-coated implants. The effect of submuscular placement on reducing contracture rates regardless of texturing is discussed, as is the apparent increase in capsular contracture in patients who smoke.     

Textured-surface saline-filled silicone breast implants for augmentation mammaplasty

The earliest silicone breast implants were smooth-surface, silicone rubber devices filled with either silicone gel or saline. Because of persistent problems with capsular contracture, polyurethane-covered silicone implants were developed as an alternative. Particularly in the short run, these alternatives proved highly successful at reducing the incidence of capsular contracture. By 1990, polyurethane-covered implants were rapidly becoming the preferred implant choice of many plastic surgeons, but for legal, regulatory, financial, and safety reasons they were withdrawn from the market by Bristol-Myers in 1991. Meanwhile, during the late 1980s, surface texturing and improved materials became available on other silicone breast implants and expanders. Most studies suggest that textured-surface silicone gel-filled implants, saline-filled implants, and tissue expanders have less frequent capsular contracture than their smooth-surface counterparts.     

Recurrence of subglandular breast implant capsular contracture: anterior versus total capsulectomy

The objective of this study was to determine whether the type of capsulectomy, anterior or total, affects the recurrence of capsular contracture around subglandular silicone-gel breast implants. A retrospective analysis was performed of patients who underwent either anterior or total capsulectomy for Baker grade 3 or 4 subglandular capsular contracture in our unit. All patients were invited to a review clinic where their capsular status was assessed. There were 100 anterior- disc capsulectomies in 60 patients between 1988 and 1997 and 99 total capsulectomies in 60 patients between 1990 and 1998. The follow-up in the former group was a median of 7 years and mean 6.9 years, compared with median 2.5 and mean 3.1 years in the latter group. Eighty-six percent of the implants removed from both groups at capsulectomy were smooth-walled gel-filled implants. Sixty-nine breasts in the anterior group received textured gel implants at capsulectomy; the remaining 31 received polyurethane-coated Meme implants. In the total capsulectomy group, all but two breasts (one patient) received textured gel implants. After review, the capsular status was known in 80 percent of the anterior and 92 percent of the total capsulectomy group. The review clinic found eight new contractures in five patients to have developed in the anterior compared with none in the total group. Recurrent contractures affected 50 percent of patients (46 percent of breasts) in the anterior and 11 percent of patients (10 percent of breasts) in the total capsulectomy group. Kaplan-Meier survival analysis was applied to the data. By including only patients who received textured gel implants at capsulectomy, the Logrank found a statistical difference between the two treatment groups (0.01 < p < 0.5). We believe that this study provides some evidence that total capsulectomy for subglandular silicone breast implant capsular contracture results in a lower capsular recurrence than anterior- disc capsulectomy. The pattern and risk of recurrence after total capsulectomy and exchange for a modern textured prosthesis appear to approach those following primary augmentation.     

Analysis of the soft-tissue response to components used in the manufacture of breast implants: rat animal model.

The implant-tissue response to the silicone gel mammary prosthesis requires a more thorough evaluation in light of recent concerns related to human connective-tissue diseases, contracture, infection, and neoplasia. The silicone prosthesis is not a homogeneous implant but is a milieu of various silicone chemistries. Silicone polymer precursors and prosthesis components (silicone shells, shells extracted of their low-molecular-weight components, silica-free silicone, silicone oil, fumed silica, and silicone extract) were implanted subcutaneously using a nonhemorrhagic technique into the backs of Lew/SsN rats (n = 90), two implants per rat, for periods of 7, 14, 28, 56, and 90 days for a total of 6 implants per material per time period. Histologic analysis was performed on specimens from the harvested soft tissue. The intensity of the cellular and capsular response was lowest for the silicone oil and increased as the material's molecular weight increased and material compliance decreased. Fumed silica elicited the most highly reactive cellular response. From this study it is apparent that the polymer's molecular weight influences its migration, encapsulation, and intensity of cellular response. Further, the silicone extract distillate elicited a highly intense cellular response with pronounced lymphocyte invasion. The human relevance of this work awaits further correlation with implant retrieval and in vivo performance.     

Capsular contracture around saline-filled fine textured and smooth mammary implants: a prospective 7.5-year follow-up.

In a previous prospective randomized clinical study comparing in the same patient textured and smooth saline-filled mammary implants (Biocell) with large pore size (300 to 600 microm), we saw no difference in capsular contracture. This study was undertaken in a similar way to compare capsular contracture around smooth and textured saline-filled prostheses with pores of small size. During a period of 7.5 years, the breast hardness was followed up, and at the end of the study patient satisfaction was evaluated.Twenty healthy women with a mean age of 30 years were operated on for breast augmentation. Two surgeons performed all operations in a standardized way. Each patient received subglandularly a Siltex textured saline-filled prosthesis with a pore size of 30 to 70 microm in one breast, and a smooth saline-filled prosthesis in the other. The hardness of the breasts was evaluated after 0.5, 1, and 7.5 years using Baker grading and applanation tonometry. Eighteen patients completed 1-year and 7.5-year follow-up. Two breasts with smooth prostheses were contracted after 6 months (Baker III or IV). After 1 year, four patients with smooth prostheses and one with a textured prosthesis had capsular contracture (p = 0.34). Seven and one-half years after surgery, six patents with smooth and four with textured implants had contracture (p = 0.66). On two patients with smooth prostheses and one patient with a textured prosthesis, the capsule around the implant hardened between 6 and 12 months. Between 1 year and 7.5 years, three breasts with smooth and textured implants contracted and one with a textured implant softened.The patients reported on a Visual Analogue Scale (1 to 10) the impact of the augmentation on their quality of life to be 9 +/- 1. Four patients preferred the breast with the smooth prosthesis, three preferred the breast with the textured prosthesis, and the others found both breasts equal. This study showed no significant difference of contracture with smooth versus fine textured implants. The majority of the patients preferred the smooth implants. The patients reported that the breast augmentation had had an extremely high impact on their quality of life.     

Comparison of the Postoperative Incidence Rate of Capsular Contracture among Different Breast Implants: A Cumulative Meta-Analysis

BackgroundA large number of clinical studies have reported that the different materials used in breast implants were a possible cause of the different incidence rates of capsular contracture observed in patients after implantation. However, this theory lacks comprehensive support from evidence-based medicine, and considerable controversy remains.ObjectivesIn this study, a cumulative systematic review examined breast augmentation that used implants with textured or smooth surfaces to analyze the effects of these two types of implants on the occurrence of postoperative capsular contracture.MethodsWe conducted a comprehensive search of literature databases, including PubMed and EMBASE, for clinical reports on the incidence of capsular contracture after the implantation of breast prostheses. We performed a cumulative meta-analysis on the incidence of capsular contracture in order from small to large sample sizes and conducted subgroup analyses according to the prosthetic material used, the implant pocket placement, the incision type and the duration of follow-up. Relative risks (RR) and 95% confidence intervals (CI) were used as the final pooled statistics.ResultsThis meta-analysis included 16 randomized controlled trials (RCTs) and two retrospective studies. The cumulative comparison of textured and smooth breast implants showed statistical significance at 2.13 (95% CI, 1.18-3.86) when the fourth study was entered into the analysis. With the inclusion of more reports, the final results indicated that smooth breast implants were more likely to be associated with capsular contracture, with statistical significance at 3.10 (95% CI, 2.23-4.33). In the subgroup analyses, the subgroups based on implant materials included the silicone implant group and the saline implant group, with significant pooled statistical levels of 4.05 (95% CI, 1.97-8.31) and 3.12 (95% CI, 2.19-4.42), respectively. According to implant pocket placement, a subglandular group and a submuscular group were included in the analyses, and only the subglandular group had a statistically significant pooled result of 3.59 (95% CI, 2.43-5.30). Four subgroups were included in the analyses according to incision type: the inframammary incision group, the periareolar incision group, the transaxillary incision group and the mastectomy incision group. Among these groups, only the pooled results of the inframammary and mastectomy incision groups were statistically significant, at 2.82 (95% CI, 1.30-6.11) and 2.30 (95% CI, 1.17-4.50), respectively. Three follow-up duration subgroups were included in the analyses: the one-year group, the two- to three-year group and the ≥five-year group. These subgroups had statistically significant results of 4.67 (95% CI, 2.35-9.28), 3.42 (95% CI, 2.26-5.16) and 2.71 (95% CI, 1.64-4.49), respectively.ConclusionIn mammaplasty, the use of textured implants reduces the incidence of postoperative capsular contracture. Differences in implant pocket placement and incision type are also likely to affect the incidence of capsular contracture; however, this conclusion awaits further study.     

The correction of capsular contracture by conversion to "dual-plane" positioning: technique and outcomes

Little has been published regarding the treatment of patients with long-established capsular contracture after previous submuscular or subglandular breast augmentation. This study reviews 7 years of experience in treating established capsular contracture after augmentation mammaplasty by relocating implants to the "dual-plane" or partly subpectoral position. A retrospective chart review was performed on all patients who were treated for capsular contracture using this technique between 1993 and 1999. Data collected included the date of the original augmentation, the original implant location, date of revision and type of implant used, length of follow-up, outcome, and any ensuing complications. Different surgical techniques were used, depending on whether the prior implant was located in a subglandular or submuscular plane. All patients had revisions such that their implants were relocated to a dual plane, with the superior two thirds or so of the implant located beneath the pectoralis major muscle and the inferior one third located subglandularly. Of 85 patients reviewed, 54 had their original implants in a submuscular position and 31 had their initial augmentation in a subglandular position. Of the 54 patients whose implants were initially submuscular, 23 patients (43 percent) had silicone gel implants, 15 patients (28 percent) had double-lumen implants, and the remaining 16 patients (30 percent) had saline implants. Of the 31 patients whose implants were initially subglandular, 20 patients (65 percent) had silicone gel implants, three patients (10 percent) had double-lumen implants, and the remaining eight patients (26 percent) had saline implants. Fifty-one patients (60 percent) had replacement with saline implants (37 smooth saline, 14 textured saline), whereas 34 (40 percent) had silicone gel implants (seven smooth gel, 27 textured gel). The average time from previous augmentation to revision was 9 years 9 months. The average follow-up time after conversion to the dual-plane position was 11.5 months. Only three of 85 patients required reoperation for complications, all of which involved some degree of implant malposition. Of patients converted to the dual plane, 98 percent were free of capsular contracture and were Baker class I at follow-up, whereas 2 percent were judged as Baker class II. There were no Baker level III or IV contractures at follow-up. The dual-plane method of breast augmentation has proved to be an effective technique for correcting established capsular contracture after previous augmentation mammaplasty. This technique appears to be effective when performed with either silicone or saline-filled implants.     

The biophysical and histologic properties of capsules formed by smooth and textured silicone implants in the rabbit.

Capsular contracture remains the major complication of reconstructive and aesthetic breast surgery. The purpose of this investigation was to determine if a silicone implant with a textured surface will form a capsule of significantly different biophysical and histologic properties than conventional smooth silicone. Thirty smooth and 30 textured silicone tissue expanders were implanted under the panniculus carnosus of rabbits. After 3 months, measurements related to contracture were performed on anesthetized animals in an investigator-blinded, controlled manner. Intraexpander pressures were measured as saline was injected over time. We found a significant correlation between intraexpander pressures, applanation tonometry, and Baker class. Histology revealed a thicker, more adherent, and inflammatory capsule around the textured silicone implants as compared with the smooth silicone implants. Dynamic pressures were plotted against volume of saline within the two types of implants. Statistical analysis revealed that the textured implants form a tighter and thicker capsule than the smooth implants after 3 months of observation (p less than 0.005).     

Rate and incidence of capsular contracture: a comparison of smooth and textured silicone double-lumen breast prostheses

Capsular contracture results in dissatisfaction and deformity among the 2 million women who have had silicone implants. The literature describes contracture rates as high as 74 percent. I present a comparison of rates and incidences of contracture in patients augmented with smooth and textured double-lumen silicone implants. A total of 165 "smooth" and 63 "textured" implant patients were included in this study, which spans 12 years, 1978-1990. All patients underwent bilateral aesthetic augmentation performed by the same surgeon. Of the 165 smooth implant patients, 74 (44.8 percent) experienced contractures requiring treatment. Of the 63 textured implant patients, 3 (4.8 percent) previous contracture patients experienced sudden fibrosis within 3 months. All others remained soft. It appears that deeply textured silicone surfaces delay or decrease the rate and incidence of clinical capsular contracture, at least for 2 years.     

Polyurethane foam-covered implants and capsular contracture: a laboratory investigation

Experiments were conducted in rabbits comparing polyurethane foam-covered implants with otherwise identical smooth silicone gel implants. Using five objective methods of measurement of capsular contracture, no significant difference could be identified. The foam-covered implants consistently developed capsular contracture, although in most cases this was of mild degree and would not have been clinically significant. In the two foam-covered implants with hard contractures, there was no evidence of hematoma or separation of the foam.     

Long-term results of MISTI gold breast implants: a retrospective study

MISTI Gold breast implants (Bioplasty, St. Paul, Minn.) filled with polyvinylpyrrolidone-hydrogel were developed as a promising alternative to silicone-filled implants. Some studies have reported on the positive effects of the implant, such as improved radiolucency and biocompatibility of the gel; however, there are also reports that such implants increased in volume and were subject to capsular contracture in the human body, resulting in demands for their removal. The purpose of this retrospective study was to analyze the long-term results of a series of patients with MISTI Gold breast implants. Between 1991 and 1993, the authors inserted 83 MISTI Gold implants in 61 patients with an average age of 46 years (range, 16 to 69). The authors were able to follow up 48 patients with 71 MISTI Gold implants. The average follow-up was 68 months (range, 10 to 108 months). The retrospective study found that 59 percent of all MISTI Gold implants were removed after an average period of 4.14 years. The main reason for implant removal was an increase in volume of 38 percent, followed by capsular contracture in 14 percent of all 71 MISTI Gold implants. The average increase in volume of all removed MISTI Gold implants was 43 percent. Capsular contracture was graded as Baker I and II in 63 percent and as Baker III and IV in 37 percent. In conclusion, the authors believe that MISTI Gold implants do not fulfill the criteria of safe breast implants, and they agree with the December of 2000 opinion of the Medical Devices Agency of the Department of Health in London that the hydrogel-filled breast implants should not be used until more information about the filler material and its metabolic fate is available.     

Analysis of risk factors associated with rupture of silicone gel breast implants

Despite many recent studies on breast implant rupture, there is no general consensus on causation or incidence. Existing studies have not reported a multivariate analysis of risk factors associated with breast implant rupture. Most studies lack adequate sample size to study the effect of implant type, manufacturer, and other patient-related factors that might affect rupture. This study addresses all of these shortcomings. Patients undergoing implant removal by a single surgeon between 1990 and 1996 were examined for rupture and for 16 potential risk factors. The association between rupture and various factors was analyzed by univariate and multivariate analyses. A total of 842 patients underwent removal of 1619 implants. Increasing age of implant [p < 0.0001; adjusted odds ratio (OR), 1.20; 95% confidence interval (CI), 1.15 to 1.23], retroglandular location (p = 0.0002; OR, 1.93; CI, 1.37 to 2.71), Baker contracture grades III and IV (p = 0.005; OR, 1.52; CI, 1.14 to 2.03), and presence of local symptoms (p = 0.05; OR, 1.37; CI, 1.00 to 1.89) were associated with rupture. When different implant types were compared with smooth gel implants, after adjustment, double-lumen (p < 0.0001; OR, 0.33; CI, 0.22 to 0.50) and polyurethane-covered implants (p < 0.0002; OR, 0.33; CI, 0.20 to 0.57) had significantly lower rupture rates. When various manufacturers were compared with Dow Corning after adjusting for other factors, rupture rates were significantly lower for McGhan (p < 0.0001; OR, 0.41; CI, 0.26 to 0.65), whereas higher for Surgitek (p < 0.019; OR, 1.52; CI, 1.05 to 2.18). Significant risk factors for breast implant rupture were identified: older implants, retroglandular implant location, implant contracture, local symptoms, certain implant type, and certain manufacturer. Although the results of this study are based on a nonrandomized explant population from a single surgeon's practice, knowledge of these risk factors will permit better interpretation of future data on rupture. The knowledge will enable the medical community to better advise their breast implant population regarding durability and appropriate time for removal or replacement.     

Comparison of the capsular response to the Biocell RTV and Mentor 1600 Siltex breast implant surface texturing: a scanning electron microscopic study.

The utility of mammary prosthesis texturing in the prevention of capsular contracture was established some 20 years ago. Various models of implant texturing are currently on the market. We decided to study two of the most popular implants with two different surface texturings: the Biocell RTV and the Mentor 1600 Siltex. An observation at the electron microscopic level of the implants' surfaces was achieved. At the time of a prospective survey on 10 patients, the capsule fragments corresponding to these two prostheses have been analyzed at the electron microscopic level. All prostheses were removed from the patients because of asymmetry or bad positioning. The aim of our study was to establish a correlation between these two frequent texturing surfaces and their corresponding capsules. Our results showed that only the Biocell's capsules present a mirror image with correspondence of the depressions on the prosthesis and contacts on the capsule. This phenomenon seems linked to the existence of a critical size of the pores constituting the implant surface. This observation leads us to the hypothesis of an adhesive effect between the prosthesis and its capsule. If this last is not directly linked to the prevention of capsular contracture, it can have an effect on implant stabilization in the primary mammary reconstruction and in the secondary corrections of asymmetry or bad position.     

Silicone gel-filled breast implant integrity: a retrospective review of 478 consecutively explanted implants

Concern has been expressed over the long-term integrity of silicone gel breast implants. There are no large series representing experience with these implants outside of the United States. A retrospective case note review of explanted silicone breast implants was performed; 478 implants have been explanted during the past 11 years and relate to the use of these devices since 1971. Loss of implant integrity was not simply related to its age in vivo. Failure was more likely with implants of the late 1970s and early 1980s (second generation) and with subpectoral placement. Implant failure was independent of capsular contracture as the indication for removal (p = 0.09). There is no evidence that the currently used textured silicone gel breast implants are subject to the same loss of integrity as previous examples of these devices. The life span of these implants, the first of which are approaching 10 years in vivo, is at present unknown. Information concerning the integrity of silicone gel breast implants is essential in the current climate for counseling of both new and old implant recipients.     

Radiolucent prosthetic gel.

The successful use of silicone breast implants is complicated by their interference with mammography. We have evaluated clinically available implant filling materials and found that a new Bio-Oncotic gel approximates the radiolucency of normal breast tissue. Silicone implants completely obscure areas of the breast in mammography. Recently proposed as a filler material, peanut oil is significantly more radiolucent than normal tissue. Physiologic saline solution compares favorably as a tissue-density-simulating substance. However, saline's lack of lubricating properties results in leakage, making it less than optimal. Bio-Oncotic gel is biologically compatible. We conclude that this gel is the most appropriate filler for breast prostheses. Clinical studies are indicated.