Near-infrared imaging of the human breast: complementing hemoglobin concentration maps with oxygenation images

We have previously reported a comparison between edge- corrected near-infrared optical mammograms and those that have un- dergone a further image-processing step based on a spatial second derivative. In this work, we go a step further by combining the second-derivative images from four wavelengths (690, 750, 788, and 856 nm) to obtain oxygenation-index images. While the spatial sec- ond derivative improves contrast and allows for visibility of fine struc- tures in the images, thereby improving the sensitivity to tumor detec- tion, additional information is needed to avoid false-positive results. The oxygenation-index images are introduced to address this issue. Oxygenation information may help discriminate benign from malig- nant breast lesions, thereby effectively complementing single- wavelength optical mammograms that display optically dense regions within the breast with high sensitivity. © 2004 Society of Photo-Optical Instru- mentation Engineers. (DOI: 10.1117/1.1805552)