Figure 2.

Illustrative images of HbO₂ (red) and Hb (blue) from the flexor aspect of the human forearm obtained with the MSOT technology during the reactive hyperemia induced by arterial occlusion with suprasystolic pressure. Different vascular structures parallel to the skin surface are depicted by the different colored chromophores at different depths during the different phases of the experimental protocol and are assumed to correspond to the superficial and the deep skin plexus. Additional subcutaneous structures can also be detected at deeper locations, although with reduced resolution.