DOT of ICG enhancement obtained simultaneously with gadolinium-enhanced MRI of the same breast affected by an 8-mm ductal carcinoma. (a) Sagittal magnetic resonance image of the breast (in grayscale) superimposed with the gadolinium enhancement (in color). The cancerous lesion appears enhanced in the center of the image because of gadolinium administration. (b) Coronal DOT image of the absorption coefficient change due to ICG distribution. This image is perpendicular to the plane of the MRI image in (a) and is obtained for the volume of interest indicated on (a) with the dashed line box. (c) Functional magnetic resonance coronal reslicing of the volume of interest with the same dimensions as (b). Gadolinium enhancement is averaged over the volume of interest and appears in color. The cancer appears in the right upper corner of the coronal image and has high spatial congruence with its appearance on the DOT image. A secondary lesion on the left, middle part of the image also coregisters well with the DOT image. A third lesion, which appears on the lower boundary of the DOT image, is probably an artifact. Although single slices through the breast volume are shown here, both MRI and DOT retrieve three-dimensional information of the volume of investigation. Published with permission from Ntziachristos et al ; © 2000 National Academy of Sciences, USA.