RESUMO
BACKGROUND: Double capsule formation around breast implants is associated with implant rotation and seroma. However, the prevalence and histological characteristics remain unclear. OBJECTIVES: To quantify the prevalence of double capsule formation between different implant surface textures and to explore the histological differences between the inner- and outer capsules from breast implant capsule biopsies. METHODS: The study was performed on data from the Copenhagen Breast Implant (COBI) Biobank comparing the prevalence of double capsule formation around Allergan Biocell implants (Allergan, Dublin, Ireland), Eurosilicone Cristalline implants (GC Aesthetics, Dublin, Ireland), and Mentor Siltex implants (Mentor, Irvine, CA). The histological characteristics of the inner and outer capsules was analyzed using a validated assessment tool. RESULTS: The study included data from 588 patients and 1128 implants. Double capsule formation was found around 25 implants resulting in an overall prevalence of 2.5% for textured implants. Mentor implants with a Siltex surface had a double capsule prevalence of 0.72%, which was significantly lower than the prevalence for Allergan implants with a Biocell surface (7.8%), (P<.001), and Eurosilicone implants with a Cristalline surface (3.4%), (P=.03). Histological analysis showed that inner capsules had lower cellular density (P=.04) and were more calcified (P=.03) compared with outer capsules. CONCLUSIONS: The risk of double capsule formation was highly correlated with the roughness of the breast implant texture, with the risk of double capsule formation around Mentor Siltex implants being significantly lower than that of macrotextured implants. The histological analysis implies that loss of vascularization to the inner capsule results in a lower cellular density and more frequently calcification.
RESUMO
BACKGROUND: Capsular contracture is traditionally evaluated with the Baker classification, but this has notable limitations regarding reproducibility and objectivity. OBJECTIVES: The aim of this study was to develop and validate procedure-specific histopathological scoring systems to assess capsular contracture severity. METHODS: Biopsies of breast implant capsules were used to develop histopathological scoring systems for patients following breast augmentation and breast reconstruction. Ten histological parameters were evaluated by multivariable logistic regression to identify those most associated with capsular contracture. Significant parameters (P < .05) were selected for the scoring systems and assigned weighted scores (1-10). Validation was assessed from the area under the curve (AUC) and the mean absolute error (MAE). RESULTS: A total of 720 biopsies from 542 patients were included. Four parameters were selected for the augmentation scoring system, namely, collagen layer thickness, fiber organization, inflammatory infiltration, and calcification, providing a combined maximum score of 26. The AUC and MAE for the augmentation scoring system were 81% and 0.8%, which is considered strong. Three parameters were selected for the reconstruction scoring system, namely, fiber organization, collagen layer cellularity, and inflammatory infiltration, providing a combined maximum score of 19. The AUC and MAE of the reconstruction scoring system were 72% and 7.1%, which is considered good. CONCLUSIONS: The new histopathological scoring systems provide an objective, reproducible, and accurate assessment of capsular contracture severity. We propose these novel scoring systems as a valuable tool for confirming capsular contracture diagnosis in the clinical setting, for research, and for implant manufacturers and insurance providers in need of a confirmed capsular contracture diagnosis.