Fluorescence-mediated tomography (FMT) detects a near-infrared fluorescence signal derived from exogenous enhanced green-fluorescent-protein (eGFP)/1,1′-dioctadecyl-3,3,3′,3′-tetramethylindotricarbocyanine iodide (DiR) macrophages recruited into carotid artery plaques of apolipoprotein E-deficient (ApoE^-/-) mice. (A–D) FMT detected a strong near-infrared fluorescence signal in the left carotid artery that was subjected to guidewire injury (GWI). Near-infrared fluorescence was absent in the right control vessel. Coronal, sagittal, and transverse sections of a mouse, 2 weeks after GWI and 7 days after injection of eGFP/DiR-labeled macrophages, are displayed. Note the absence of fluorescence at the contralateral control-side (*). The color coding represents the concentration of DiR. (E) In sham-operated animals (n = 4), FMT signals were similar between left and right carotid artery or between day 2 and day 7. (F) After GWI the FMT signal was increased after 2 days (n = 9) and remained elevated on day 7 (n = 8), with a significant difference between right (sham) and left (GWI) carotid artery (P < 0.05). One animal died before FMT analysis on day 7. contr. = control; L = left; nm = nanomolar; R = right.