Considering the findings above reported, the objectives of this study were (1) to morphologically confirm and better evaluate the role of MLT in modulating perivascular brown adipose tissue of apolipoprotein-E knockout (ApoE-/-) mice, a known model of atherosclerosis; and (2) to compare the morphological evaluations with results obtained with 18F-FDG PET combined with computed tomography (PET/CT) in order to better define the possible use of these analyses in the detection of early-stage atherosclerosis and its progression. The gene discussed is APOE; the disease is atherosclerosis.