Capsular contracture after breast reconstruction: collagen fiber orientation and organization.

Background: Breast implant capsular contracture is a common complication of implant-based breast reconstruction. To develop nonsurgical interventions to combat breast capsular contractures, a clearer understanding of the process is required. Comparing breast implant-related capsular contracture to the fibrotic scarring process, the hypothesis is that these processes differ with regard to the compaction of collagen fibers within the connective tissue matrix.

Methods: Morphologic differences in the connective tissue matrix by light, polarized light, and fluorescence microscopy documents these differences. Discarded Baker grade II and III periimplant capsules harvested during routine breast reconstructive operations were used for the evaluation.

Results: Within severe breast capsule contractures, light microscopy revealed the absence of mast cells, whereas polarized light microcopy showed that collagen fiber bundles were consolidated into thick cable-like structures. In less severe breast capsules, mast cells were present, whereas thick cable-like collagen structures were absent. By fluorescence microscopy, fibroblast populations associated with severe contractures were oriented perpendicular to the long axis, suggesting a spiral orientation in the compaction of these cable-like structures. These findings were absent in less severe contractures.

Conclusions: To the authors' knowledge, these histologic findings in breast implant capsules are unreported and unique when compared with other fibrotic contractures. Elucidating the biological mechanisms involved in the reorganization of collagen fiber bundles that lead to implant-related capsular contracture is a critical step for developing strategies to treat and control breast capsule contractures.