Citation: Cancer Researcher Weekly, July 12, 1993 p23(2)
Subjects: Breast implants_Materials Mammography_Testing
Reference #: A14026487
Full Text COPYRIGHT Charles Henderson, Publisher 1993
SOURCE: Plastic and Reconstructive Surgery, May 1993;91(6):1057-1062.
Triglyceride solution provides the best mammographic visualization of breast tissue of any breast implant filler material studied, California researchers report.
Neal Handel and colleagues from the Breast Center, Van Nuys, California, had breast implant shells filled with different materials, including silicone gel, normal saline, a triglyceride solution, a solution of 50 percent polyvinylpyrrolidone (PVP) in saline, a solution of 10 percent PVP in saline and a solution of 2.5 percent PVP in glycerine.
A woman scheduled to undergo total mastectomy for a solid benign tumor and an area of microcalcifications was recruited for the study, and a series of mammograms were made with the implants placed between the breast and the underlying film cassette holder. Because of the impending surgery, it was not felt that the multiple radiation exposures constituted a health risk.
The implant containing triglyceride solution provided the best visualiztion of the tumor mass and microcalcification. "The lesions could be seen with progressively less clarity through 50 percent PVP in saline, 2.5 percent PVP in glycerine, saline and 10 percent PVP in saline," reported Handel et al. "The lesions could not be visualized at all through silicone gel."
The authors noted that four factors contribute to the attenuation, or weakening, of X-rays. These are the energy level of the radiation (kV), the density of the material being X-rayed, the atomic number of the material being X-rayed and the number of electrons per gram. In their discussion, they commented on the appropriateness of triglyceride solution in regard to some of these attenuation factors.
"It is noteworthy that the triglyceride solution interfered least with visualization of the lesions," they wrote. "Triglycerides have a physical density similar to the components of a living breast. Since the predominant atom in triglycerides is carbon (atomic no. 6), this material is similar to breast tissue with regard to atomic number as well. This study indicates that the search for the ideal filler for breast implants should concentrate on materials that have physical properties (including physical density and atomic number) similar to breast tissue. This suggests that some organic compound, a biocompatible liquid or gel with a density similar to soft tissue, would be ideal. Most likely this would be some type of fat or oil. It is worth emphasizing that the ideal filler material is not the one that is most radiolucent (such as air), because this would allow excessive transmission of X-rays and result in overexposure of breast tissue in the path of the implant. The ideal filler (radiologically) would be one with attenuation characteristics most like breast parenchyma."
The corresponding author for this study is Neal Handel, M.D., the Breast Center, 14624 Sherman Way, Van Nuys, California 91405.