A Comparison of the Capsules Around Smooth and Textured Silicone Prostheses used for Breast Reconstruction A Light and Electron Microscopic Study

Abstract

A total of 18 women who had undergone modified radical mastectomy and tissue expansion for breast reconstruction were studied. When the expanders were replaced, nine patients had received smooth, gel-filled permanent prostheses and nine had received textured, gel-filled permanent prostheses. For medical reasons, e.g. capsular contraction, incorrectly placed or sized implant, an additional operation was performed, and then biopsy specimens from the capsules around the prostheses were taken and subsequently examined with the aid of the light and transmission electron microscope (TEM). A histologist was able to classify blindly 11 capsules out of 13 which were investigated by light microscopy in the correct groups and several differences between the capsules were found. Capsules around the smooth implants had a clear line of separation between the inner surface and the prosthesis, and formed a single collageneous layer. They were sparse in fibroblasts, which were long and thin. Capsules around textured implants consisted of two layers, the outer layer being compact with long, slender fibroblasts, and the inner one looking rugged with wavy bundles of collagen often splitting from each other, and with shorter and more rounded fibroblasts. The overall thickness seemed greater compared to the capsules around the smooth prostheses, which, on the other hand, showed a greater variation in thickness. To analyze collagen fibril diameters, sample sections were photographed at magnification 22 000 in the TEM. The fibril diameters were measured with an interactive image analysis system (IBAS). The mean diameter of the collagen fibrils was 47.2 nm in the capsules around the smooth prostheses and 51.7 nm in the capsules around the textured prostheses. This difference is not statistically significant.

Key Words:

• tissue expansion
• breast reconstruction
• silicone prostheses
• smooth prostheses
• textured prostheses
• capsular tissue
• light microscopy
• transmission electron microscopy
• computer-assisted image analysis
• collagen dimensions