Visualization of silicone gel in human breast tissue using new infrared imaging spectroscopy

Between 1 and 2 million women in the United States have silicone breast implants. Complications include capsular contracture and calcification and possibly connective tissue diseases such as scleroderma and rheumatoid arthritis, a subject of some controversy. In order to accurately assess the role of silicone in any histopathologic change, it is necessary to confirm its presence and to identify other foreign materials in the capsular tissue. Although light microscopy is used to visualize regions of tissue containing foreign inclusions, their chemical identity can only be determined using analytical techniques such as infrared or Raman microscopy. However, these conventional microprobe techniques record spectra only at single points and require an a priori knowledge of the locations of the inclusion to be probed. To significantly extend the capabilities of both infrared spectroscopy and optical microscopy, we have developed a new infrared imaging system that completely integrates these two methods. In this manuscript we highlight the ability of the technique to screen rapidly and to determine accurately the presence, size and chemical composition of silicone gel inclusions in human breast tissue.