Diffuse Optical Tomography & Spectroscopy
Light can travel through human flesh. Diffuse optical tomography and spectroscopy take advantage of this phenomenon to generate three-dimensional images of the breast. As light moves through tissue, it is largely scattered by red oxygenated blood, blue deoxygenated blood, yellow fats, and water. By sending in laser pulses of different colors at one end of the breast and measuring how different colors of light spread through the breast, computers can generate three-dimensional maps of these four substances inside the breast. Darker, redder regions indicate a high blood supply to a tumor. The laser radiation used here is not ionizing, and so does not have a risk of causing cancer. This technology has yet to be implemented in clinical settings.