MORPHOLOGIC CHARACTERIZATION OF POLYVINYL SPONGE (IVALON) BREAST PROSTHESIS

Background.-Although almost all breast implants are made of silicon, s ome implants, especially the ones used in early augmentation mammoplas ty, were made of other materials, one of which is polyvinyl alcohol (c ommercially known as the Ivalon sponge). The morphology of this type o f breast implant and its associated tissue reactions have not been cha racterized in detail. Materials and Methods.-A pair of polyvinyl breas t prostheses implanted 40 years ago in a 66-year-old woman were remove d together with their capsules to correct progressive disfiguration. T he implants and capsules were radiographed. Sections from these specim ens were subjected to routine histologic studies and special stains, i ncluding periodic acid-Schiff and Masson's trichrome stains. Results.- The breast implants were composed of crystals with a pathognomonic mor phology. By hematoxylin-eosin stain, these crystals were polygonal, co lorless, and refractile, but nonbirefringent, and they had a character istic bubbling internal structure. The crystals displayed a deep-blue color with Masson's trichrome stain and were strongly periodic acid-Sc hiff-positive, with or without diastase digestion. These crystals appe ared isolated or interconnecting and were separated from one another b y spaces filled with tissue fluid. The capsules were composed of the s ame kind of crystals, but they were heavily calcified and associated w ith dense fibrosis and occasional multinucleated giant cells. Conclusi ons.-This case serves to emphasize that breast prostheses made of mate rials other than silicon may be rarely encountered in the surgical pat hology laboratory. Although polyvinyl breast implants were abandoned, injection of polyvinyl into various tissues for therapeutic purposes i s sometimes indicated. The morphologic features of polyvinyl as detail ed in this study should enable prompt and accurate recognition of this material, whether it is in breast implants or other types of tissue.