Prevalence of silicone breast implant rupture among Danish women

The durability of silicone gel-filled breast implants is of concern, but th ere are few epidemiological studies on this issue. To date, most of the rel evant findings are derived from studies of explantation, which suffer from bias by including women, vith symptoms or concerns about their implants. As part of a long-term magnetic resonance imaging study of the incidence of r upture, this study involved 271 women with 533 cosmetic breast implants who were randomly selected from among women who underwent cosmetic breast impl antation from 1973 through 1997 at one public and three private plastic-sur gery clinics in Denmark. The prevalence of rupture was determined from the first magnetic resonance screening. The images were evaluated by four indep endent readers, using a standardized, validated form. The outcomes under st udy were rupture, possible rupture, and intact implant. Ruptures were categ orized as intracapsular or extracapsular. Overall, 26 percent of implants i n 36 percent of the women examined were found to be ruptured, and an additi onal 6 percent were possibly ruptured. Of the ruptured implants, 22 percent were extracapsular. In multiple regression analyses, age of implant was si gnificantly associated with rupture among second- and third-generation impl ants, with a 12-fold increased prevalence odds ratio for rupture of implant s that were between 16 and 20 years of age, compared,vith implants between 3 and 5 years of age. Surgitek implants (Medical Engineering Corporation, R acine, Wis.) had a significantly increased prevalence odds ratio of 2.6 for rupture, compared with the reference implants. No significant association was found with the position (subglandular or submuscular) or the type of im plant (single- or double-lumen). Extracapsular ruptures were significantly associated with a history of closed capsulotomy (p = 0.001). In the future, the authors plan to examine the women in their cohort with a second magnet ic resonance imaging scan to establish the incidence of rupture, a paramete r unknown to date in the literature, and to further characterize those fact ors associated with the actual risk of rupture.