1. A method for optical imaging of a turbid medium, which method comprises—a reference measurement of reference intensities of light emanating from the turbid medium at a reference blood oxygen saturation (SaO2) in the turbid medium, —and a reference imaging step for reconstructing a reference image of the turbid medium from the measured reference intensities, and wherein further a contrast measurement of the contrast intensity of the light emanating from the turbid medium at a contrast blood oxygen saturation (SaO2) in the turbid medium, and a contrast imaging step for reconstructing a contrast image of the turbid medium from the measured contrast intensities, and a comparison is made between the contrast image to the reference image of the turbid medium.