NATURE OF THE COLLAGENOUS CAPSULES AROUND BREAST IMPLANTS - LIGHT AND ELECTRON-MICROSCOPIC INVESTIGATIONS

Fibrous tissue capsules around silicone-gel and saline-filled breast implants were examined by light microscopy, by transmission electron microscopy, and by scanning electron microscopy. This study revealed the following. 1. Regularly arranged dense connective tissue forms the basis of the reactively developed capsules around the breast implants. This tissue contains bundles of collagenous fibers which are densely packed and lie parallel to each other, forming structures of great tensile strength. 2. The outer surface of the connective tissue capsules contains reticulum fibers, small in diameter. These fibers branch variously to form a net- like framework which supports the collagenous material. 3. At the inner surface fibrocytes and histiocytes are present in single layers and form an epithelial-like structure. 4. The connective tissue of the capsules also contained capillaries and fibrocytes, which were usually deployed along bundles of collagen fibers and appeared as fusiform elements with long processes. The fibrocytes also contained lyso- somes, involved in hydrolysis or digestion of material within the cell. 5. Contractile fibroblasts (myofibroblasts) were found in these fibrous capsules. However, deformation of the augmented breast cannot be caused by the action of the myofibroblasts, because the number is too small. More likely, it is caused by the inelastic arrangement of large amounts of collagenous material in the capsule. © 1979American Society of Plastic Surgeons.