Fig. 1From: Preoperative endothelial dysfunction in cutaneous microcirculation is associated with postoperative organ injury after cardiac surgery using extracorporeal circulation: a prospective cohort studyEvaluation of cutaneous microcirculation. a Iontophoresis in combination with blood perfusion imager. b Incident light from the laser (thick red arrows) are scattered back (dotted arrows) from red blood cells flowing in the microvessels. c Typical dose–response-related vasodilatation as a response to ACh (blue) and SNP (red)—blood perfusion imaging. Photos reproduced with the permission of Perimed (Järfälla, Sweden)Back to article page