S. Lori Brown et al., American Journal of Roentgenology. 2000.

ABSTRACT :

OBJECTIVE. Silicone gel breast implants have been reported to rupture, but the prevalence of implant rupture in an unreferred population of women is not known. The objective of this study was to assess the prevalence of implant rupture and the presence of extracapsular silicone gel in an unreferred population of women without regard to the absence or presence of any local or systemic symptoms.

SUBJECTS AND METHODS. Women identified as part of a National Cancer Institute cohort study on breast implants, living in the Birmingham, AL, area were invited to undergo MR imaging of their current silicone gel breast implants at the Kirklin Clinic at the University of Alabama at Birmingham. Three radiologists independently examined and rated all MR images for signs of implant rupture and extracapsular silicone.

RESULTS. A total of 344 women with silicone gel breast implants underwent MR imaging. Breast implant rupture was reported by at least two of three radiologists for 378 (55.0%) of the 687 implants in this study. Another 50 implants (7.2%) were rated as indeterminate (suspicious) for rupture. A majority of women in this study, 265 (77.0%) of 344, had at least one breast implant that was rated as ruptured or indeterminate. Radiologists also agreed that silicone gel could be seen outside the fibrous capsule that forms around the implant in 85 (12.4%) of the 687 implants affecting 73 women (21.2%). Factors that affected implant rupture were implant age and location (submuscular or subglandular). The median implant age at rupture was estimated to be 10.8 years with a 95% confidence interval of 8.4-13.9 years.

CONCLUSION. The prevalence of silent or occult silicone gel breast implant rupture is higher than was previously suspected. Most women in this study had MR imaging evidence of at least one ruptured silicone gel breast implant.

Read full article here.

FDA, Sixth World Biomaterials Conference. May 18, 2000.

FDA has recently completed a study on how often women who had breast implants had to go back to their surgeons for additional surgery on their breast(s). The study was presented at the Sixth World Biomaterials Congress on May 18, 2000.

The study, performed in Birmingham, Alabama, involved women who had their first breast implant before 1988. The majority of women in this study had silicone gel-filled breast implants. Women responded to a telephone questionnaire in which they described past surgeries and whether or not their implants were found to be ruptured after the surgeries. Women also responded to questions about the reason they had the surgery.

The Institute of Medicine recently released its report on the safety of silicone breast implants. It concluded that the primary problems with silicone implants were local complications, including implant removal, ruptures, deflations, capsular contracture, infection, and pain.

FDA conducted this study because of concerns about the frequency and results of rupture. Rupture is a concern because:

• Rupture of silicone gel-filled implants may allow silicone to migrate through the tissues. The relationship of free silicone to development or progression of disease is unknown.

• Rupture is a device failure – the implant is no longer performing as intended.

Read the full study here.

FDA, Sixth World Biomaterials Congress. May 18, 2000.

An FDA study on rupture of silicone gel-filled breast implants was presented at the Sixth World Biomaterials Congress on May 18, 2000.

The study, performed in Birmingham, Alabama, involved women who had their first breast implant before 1988. The majority of the 907 women in this study had silicone gel-filled breast implants. Some women who had silicone gel-filled breast implants were invited to undergo a magnetic resonance imaging (MRI) examination of their breasts to determine whether their implants had ruptured. MRI allows the radiologist to see the breast implant while it is still inside the breast.

FDA conducted this study because of concerns about the frequency and results of rupture. Rupture is a concern because:

– Rupture of silicone gel-filled implants may allow silicone to migrate through the tissues. The relationship of free silicone to development or progression of disease is unknown.

– Rupture is a device failure – the implant is no longer performing as intended.

Protocol
– Women in this study were identified because they had been in a National Cancer Institute study on women with breast implants. Women who responded to a questionnaire in the NCI study were eligible for this study. This cohort included only women who were patients at two plastic surgery practices. The 907 women in this study were a subset of 1247 women in the Birmingham, Ala., area who were part of an NCI study on breast implants.
– The rupture study had two parts. In the first part, 907 women were interviewed about surgeries in which implant(s) were surgically removed (interview component of the study).
– One third of the 907 women in the first part of the study reported that they had at least one surgery in which their implant was removed and replaced. Women were also asked the main reason they had their implants removed, and if an implant rupture was suspected prior to the surgery.

– If women reported that their implant surgery was for a suspected implant rupture, they were asked about symptoms that they may have had and about whether they knew of a possible cause of the rupture.
– In the second part of the study, 344 women with silicone gel breast implants received MRI examinations to detect possible implant rupture. The women, selected randomly from the first part of the study, were invited to have MRI exams when they were called to be in the study until all the MRI appointments planned for the studyhad been filled. The study had funding for up to 400 MRI exams to be accomplished at a particular MRI facility under contract for a certain period of time. Of the 445 women invited to have an MRI, 80% (359) accepted and had the examination. Women were invited for the MRI exam without regard to whether they had symptoms of breast implant rupture. Those who accepted the appointments and came were no more likely to think their breast implant was ruptured than women who declined the examination or did not come to their appointments.
– The 344 women who received MRI examinations had a total of 687 implants. The average age of the women in the MRI cohort was 51 ± 8 years. Most women in this cohort had a single lumen gel breast implant (82%) and the remainder had a double-lumen gel breast implant (silicone and saline). For the 677 implants for which this information was available, the average implant age was 17 ± 3 years.
– Three independent radiologists reviewed the results of all of the women’s MRIs and for each implant, determined whether it was intact, indeterminate (suspicious for rupture), or ruptured. The agreement between the radiologists was very high.

Results
– At least two of the three study radiologists agreed that 378 of the 687 implants were ruptured (55%). This means that 69% of the 344 women had at least one ruptured breast implant.
– Radiologists observed that silicone gel had leaked outside the fibrous scar capsule that forms around the implant in 85 of the 687 implants (12%). Of the 344 women, 73 (21%) had silicone gel outside the capsule in one or both breasts.
– Factors that were associated with rupture: the age of the implant, the implant manufacturer, and whether the device was implanted above or beneath the chest muscles.

Limitations of the Study
– This cohort included only women who were at two plastic surgery practices. It is unknown whether the results of the study might have been different if patients from other parts of the U.S. had been included.
– Only 80% of those invited to have an MRI examination agreed.
– Many types of silicone gel-filled breast implants were included in this study.
– While MR imaging is considered the best method for imaging breast implants for rupture, it is not perfect.

Conclusion
– MRI examination in this cohort of patients demonstrated that the majority of women had at least one ruptured implant.

Funding and Authors
– Funding for this study came from: the Office of Women’s Health, FDA; the Office of the Commissioner; the National Cancer Institute, NIH; the Office of Research on Women’s Health, NIH; and the U.S. Department of Health and Human Services.
– Authors were S. Lori Brown, PhD, MPH , Michael S. Middleton, PhD, MD ² , Wendie A. Berg, MD, PhD ³ , Mary Scott Soo, MD ⁴, and Gene Pennello, PhD ¹.

Read full study here.