“…Therefore, FDG uptake would not necessarily be associated with a deleterious outcome, depending on the cells or cell subtypes present in the aneurysm. For example, there are two antagonist subtypes of macrophages within vascular lesions that could not be distinguished by FDG PET: one pro-atherogenic and pro-inflammatory type, called M1, and the opposite, called M2 [ 98 ]. It nevertheless makes sense that FGD uptake tracks inflammation, but the counterhypothesis that inflammatory activity in the aortic wall would be the consequence of expansion rather than the cause has never been tested.…”