Assessment of inflammation in large arteries with 18F-FDG-PET in elderly

Abstract

This paper presents repeated measurements of atherosclerosis using bimodality positron emission tomography and computed tomography (PET/CT) with 18F-fluorodeoxyglucose (18F-FDG) to assess its uptake in aorta, iliac and femoral arteries in three groups of elderly subjects classified as normals (N), hypercholesterolemics (H) and with stable angina (A) in a 12 months follow-up (T0 to T12). The subjects in group H were taking rosuvastatin (20mg/d) for 12 months before the second scan. The calcifications in the arteries were determined by CT imaging and the artery PET images were analyzed slice by slice. The standard uptake values (SUVs) for 18F-FDG uptake were classified in two main groups: calcified and non-calcified arteries and each main group comprises six sub-groups for the three subject groups N, H and A, and for the two measurements 12 months apart. Although the calcifications were present at some portions of the arteries in all subjects (23%, 36% and 44% of calcified sites to total sites analyzed, respectively, in groups N, H and A), the results show the most noticeable SUV changes after 12 months was in group N of non-calcified arteries. In the three groups, the calcified arteries showed no significant differences between T0 and T12 while significant differences were observed for the non-calcified arteries. However, there were no significant changes at T12 between groups N and H following rosuvastatin intake in group H. In conclusion, the quantitative analysis with 18F-FDG-PET/CT could be efficient in the localization of the inflammation and evaluation of its progression in atherosclerosis instead of global evaluations with systemic inflammation biomarkers.

Keywords: 18F-Fluorodeoxyglucose; Aging; Atherosclerosis; Inflammation; Large arteries; Positron emission tomography.